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Dreyer, Rosenkranz & Droop Steam Engine Indicator

view Dreyer, Rosenkranz & Droop Steam Engine Indicator digital asset: Dreyer, Rosenkranz & Droop Steam Engine Indicator
Measurements:
overall: 8 3/8 in x 6 1/4 in x 3 in; 21.2725 cm x 15.875 cm x 7.62 cm
Object Name:
indicator, steam engine
Description:
Dreyer, Rosenkranz, & Droop manufactured this steam engine indicator, serial number 10633. It cannot be disassembled for inspection. The stylus is missing.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift from Estate of Kalman J. Dejuhasz, state College, Pennsylvania
ID Number:
1981.0217.15
Accession number:
1981.0217
Catalog number:
1981.0217.15
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Work and Industry: Mechanical and Civil Engineering
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847419

Tabor Steam Engine Indicator

view Tabor Steam Engine Indicator digital asset: Tabor Steam Engine Indicator, Patented on December 10, 1878
Maker:
Ashcroft Mfg. Co.
Physical Description:
wood (case material)
Measurements:
walnut case-from catalog card: 8 1/2 in x 6 in x 10 in; 21.59 cm x 15.24 cm x 25.4 cm
overall: 5 7/8 in x 9 3/4 in x 8 in; 14.9225 cm x 24.765 cm x 20.32 cm
Object Name:
indicator, steam engine
Place made:
United States: Connecticut
Description:
Ashcroft Mfg. Co. of Bridgeport, Connecticut, manufactured this Tabor steam engine indicator, serial number 2418. It consists of a steel piston with three grooves and a guide below the spring; a vented brass cylinder; an internal, single wound spring, which can be changed; a large drum with a coil spring and a single record. There is a Houghtaling worm gear reduction apparatus and a conical brass stylus. The piston, spring, and parts of the linkage are missing. Accompanying the indicator is a box with extra springs, piston, and worm reduction gear.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois
ID Number:
MC.316790
Catalog number:
316790
Accession number:
228496
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847290

Crosby Steam Engine Indicator

view Crosby Steam Engine Indicator digital asset: Crosby Steam Engine Indicator
Maker:
Crosby Steam Gage & Valve Company
Physical Description:
wood (case material)
Measurements:
overall: 4 5/8 in x 7 3/4 in x 7 1/8 in; 11.7475 cm x 19.685 cm x 18.0975 cm
walnut case - from catalog card: 4 3/4 in x 6 3/4 in x 7 3/4 in; 12.065 cm x 17.145 cm x 19.685 cm
Object Name:
indicator, steam engine
Place made:
United States: Massachusetts
Description:
Crosby Steam Gauge & Valve Co. of Boston, Massachusetts, manufactured this steam engine indicator, serial number 3309. It consists of a piston, which is stuck inside the cylinder. A brass stylus can record onto a large small drum with a spiral spring and a single record. Accompanying the indicator is a box with twelve springs and a spring wrench.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois
ID Number:
MC.316795
Catalog number:
316795
Accession number:
228496
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847281
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Star Steam Engine Indicator

view Star Steam Engine Indicator digital asset: Star Steam Engine Indicator
Maker:
Star Brass Manufacturing Company
Measurements:
overall: 9 3/4 in x 6 1/2 in x 2 in; 24.765 cm x 16.51 cm x 5.08 cm
Object Name:
indicator, steam engine
Date made:
ca 1907
Description:
The Star Brass Mfg. Co. manufactured this steam engine indicator, serial number 760. It consists of a steel piston with one groove; a vented brass cylinder; an external, double wound spring, which can be changed; a small drum with a spiral spring and a single record. The stylus is missing.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Yale University, Mason Laboratory, New Haven, Connecticut
ID Number:
MC.319483
Catalog number:
319483
Accession number:
237917
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847430

Tabor Steam Engine Indicator

view Tabor Steam Engine Indicator digital asset: Tabor Steam Engine Indicator,  Patented on  December  10, 1878 and April 3, 1900
Maker:
Ashcroft Mfg. Co.
Physical Description:
wood (case material)
Measurements:
walnut case-from catalog card: 8 in x 8 1/2 in x 10 in; 20.32 cm x 21.59 cm x 25.4 cm
overall: 7 1/2 in x 9 3/4 in x 8 1/4 in; 19.05 cm x 24.765 cm x 20.955 cm
Object Name:
indicator, steam engine
Place made:
United States: Connecticut
Description:
Ashcroft Mfg. Co. of Bridgeport, Connecticut, manufactured this Tabor steam engine indicator, serial number 7171. It consists of a brass piston with three grooves; a vented brass cylinder; an external, single wound spring, which can be changed; a large drum with a coil spring and a single record. The small knob to adjust the stylus pressure is missing. Accompanying the indicator is a box with several springs and reduction gear.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois
ID Number:
MC.316792
Catalog number:
316792
Accession number:
228496
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847283

Crosby Gas Engine Indicator

view Crosby Gas Engine Indicator digital asset: Crosby Gas Engine Indicator
Maker:
Crosby Steam Gage & Valve Company
Physical Description:
wood (case material)
Measurements:
overall: 4 3/8 in x 8 in x 6 3/4 in; 11.1125 cm x 20.32 cm x 17.145 cm
walnut case - from catalog card: 4 1/2 in x 6 1/2 in x 8 in; 11.43 cm x 16.51 cm x 20.32 cm
Object Name:
indicator, gas engine
Place made:
United States: Massachusetts
Description:
Crosby Steam Gauge & Valve Co. of Boston, Massachusetts, manufactured this steam engine indicator, serial number 6163. It consists of a small steel piston (1/8 inch); a vented brass cylinder; an internal, double wound spring, which can be changed; a small drum with a spiral spring and a single record; and a brass stylus. Accompanying the indicator is a box with fourteen springs, small tools, and an extra piston with top stem.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois.
ID Number:
MC.316799
Catalog number:
316799
Accession number:
228496
Patent number:
6163
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847280
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Lippincott Steam Engine Indicator

view Lippincott Steam Engine Indicator digital asset: Lippincott Steam Engine Indicator
Physical Description:
oak (container material)
Measurements:
overall: 5 1/2 in x 9 1/2 in x 9 7/8 in; 13.97 cm x 24.13 cm x 25.0825 cm
oak case - from catalog card: 6 in x 9 1/2 in x 9 1/2 in; 15.24 cm x 24.13 cm x 24.13 cm
Object Name:
indicator, steam engine
Place made:
United States: New Jersey
Description:
The Lippincott Steam Specialty and Supply Co. manufactured this steam engine indicator, serial number 1380. It consists of a steel piston with two grooves and a bottom guide; a brass cylinder; an internal spring, which is missing; a small drum with a spiral spring and single record. The stylus is missing, but assumed to be a lead pencil point. Accompanying the indicator is a box with four springs, and extra piston, a wrench, reduction pulleys, record cards, and scales.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois
ID Number:
MC.316800
Catalog number:
316800
Accession number:
228496
Patent number:
1380
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847439
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Tabor Steam Engine Indicator

view Tabor Steam Engine Indicator digital asset: Tabor Steam Engine Indicator
Maker:
Ashcroft Mfg. Co.
Physical Description:
wood (case material)
Measurements:
overall: 6 1/4 in x 9 7/8 in x 8 5/8 in; 15.875 cm x 25.0825 cm x 21.9075 cm
walnut case - from catalog card: 6 1/2 in x 8 1/2 in x 10 in; 16.51 cm x 21.59 cm x 25.4 cm
Object Name:
indicator, steam engine
Place made:
United States: Connecticut
Description:
Ashcroft Mfg. Co. of Bridgeport, Connecticut, manufactured this Tabor steam engine indicator, serial number 2325. It consists of a brass piston with three grooves; a vented brass cylinder; an internal, single wound spring, which can be changed; a large drum with a coil spring and a single record. The end of the linkage that holds the stylus is missing, as is the pulley. Accompanying the indicator is a box with several springs.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois
ID Number:
MC.316791
Catalog number:
316791
Accession number:
228496
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Work and Industry: Mechanical and Civil Engineering
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847282
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Steam Engine Indicator

view Steam Engine Indicator digital asset: Steam Engine Indicator
Measurements:
overall: 10 in x 5 1/2 in x 4 1/4 in; 25.4 cm x 13.97 cm x 10.795 cm
Object Name:
indicator, steam engine
Description:
The American Steam Gauge Co. of Boston, Massachusetts, manufactured this steam engine indicator, serial number 6216. It consists of a brass piston; a vented brass cylinder; an external spring, which is missing; a large drum with a coil spring and single record; and brass stylus.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Yale University
ID Number:
MC.319486
Catalog number:
319486
Accession number:
237917
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847423

Thompson-American Steam Gauge Steam Engine Indicator

view Thompson-American Steam Gauge Steam Engine Indicator digital asset: Thompson-American Steam Gauge Steam Engine Indicator
Measurements:
overall: 9 in x 6 1/8 in x 3 in; 22.86 cm x 15.5575 cm x 7.62 cm
Object Name:
indicator, steam engine
Place made:
United States: Connecticut
Date made:
ca 1883
Description:
The American Steam Gauge Co. of Boston, Massachusetts, manufactured this steam engine indicator, serial number 662. It consists of a brass piston; a vented brass cylinder; an internal, single wound spring, which can be changed; a large drum with a coil spring and single record; and brass stylus.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Yale University, Mason Laboratory, New Haven, Connecticut
ID Number:
MC.319490
Catalog number:
319490
Accession number:
237917
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847422

Crosby Gas Engine Indicator

view Crosby Gas Engine Indicator digital asset: Crosby Gas Engine Indicator
Maker:
Crosby Steam Gage & Valve Company
Physical Description:
wood (case material)
Measurements:
overall: 5 3/8 in x 8 1/2 in x 8 in; 13.6525 cm x 21.59 cm x 20.32 cm
walnut case - from catalog card: 5 1/2 in x 7 in x 8 1/2 in; 13.97 cm x 17.78 cm x 21.59 cm
Object Name:
indicator, gas engine
Place made:
United States: Massachusetts
Description:
Crosby Steam Gauge & Valve Co. of Boston, Massachusetts, manufactured this steam engine indicator, serial number 8619. It consists of a steel piston with four grooves, a vented brass cylinder, an internal spring (which is missing), a small drum with a spiral spring and a single record, and a brass stylus. Accompanying the indicator is a box with twelve springs, double wound, and some small tools.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois
ID Number:
MC.316798
Catalog number:
316798
Accession number:
228496
Patent number:
8619
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Work and Industry: Mechanical and Civil Engineering
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847279
Additional Online Media:

Manographe Indicator

view Manographe Indicator digital asset number 1
Measurements:
overall - box: 4 3/4 in x 17 1/4 in x 7 in; 12.065 cm x 43.815 cm x 17.78 cm
overall - tube: 21 in x 3/4 in; x 53.34 cm x 1.905 cm
woden box - from catalog card: 6 in x 14 in x 5 in; 15.24 cm x 35.56 cm x 12.7 cm
Object Name:
manographe
manograph, indicator
Place made:
United States: Rhode Island
Description:
This manographe, or indicator, was purchased by Professor W. H. Kenerson around 1907. He used it in making tests of the Brayton Oil Engine, National Museum of American History catalog number 313.703, at Brown University.
A pivoted mirror reflects a beam of light to a photosensitive plate or paper. Changes in pressure in the engine cylinder cause the mirror to oscillate up and down; a pin and eccentric actuated by a flexible shaft connected to the engine shaft cause the mirror to oscillate from side to side.
The indicator is housed in a wooden box that is 5 inches by 6 inches by 14 inches, with a brass pipe fitting and gear box at one end. The opposite end is open to receive a plate holder of a ground glass. A T-shaped tube lets light into one side, and an adjustable prism inside directs the light to the mirror. The flexible shaft is 32 inches long and covered with black fabric. Four plate holders, one ground glass, a steel petcock and a tapered hollow steel plug are included with the instrument. It is marked “Manographe Hospitalier-Carpentier, Brevete, S G D G, J. Carpentier, Paris.”
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Professor W. H. Kenerson, Providence R. I.
ID Number:
MC.313704
Catalog number:
313704
Accession number:
192776
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Data Source:
National Museum of American History, Kenneth E. Behring Center
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edanmdm:nmah_846682

Calkins Steam Engine Indicator

view Calkins Steam Engine Indicator digital asset: Calkins Steam Engine Indicator
Physical Description:
wood (container material)
Measurements:
overall: 4 3/4 in x 9 3/4 in x 10 in; 12.065 cm x 24.765 cm x 25.4 cm
walnut case - from catalog card: 5 in x 9 3/4 in x 9 3/4 in; 12.7 cm x 24.765 cm x 24.765 cm
Object Name:
indicator, steam engine
Place made:
United States: New York
Description:
The Engineers Instrument Co. manufactured this steam engine indicator, serial number 66, which is based on patent 442102, granted to Almon B. Calkins of Bridgeport, Connecticut, on December 9, 1890. It consists of a brass piston with two grooves; a brass cylinder; and internal spring, which can be changed; a large drum with coil spring and single record. The stylus and grease cup are missing. Accompanying the indicator is a box with twelve springs.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois
ID Number:
MC.316803
Catalog number:
316803
Accession number:
228496
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847443

Integrating Steam Engine Indicator

view Integrating Steam Engine Indicator digital asset: Integrating Steam Engine Indicator
Physical Description:
wood (case material)
Measurements:
overall: 4 7/8 in x 9 3/4 in x 10 in; 12.3825 cm x 24.765 cm x 25.4 cm
overall - from catalog card: 4 in x 7 in x 7 in; 10.16 cm x 17.78 cm x 17.78 cm
Object Name:
indicator, steam engine
Description:
This device is designed to integrate the area under the indicator diagram and will total the work for several strokes of the piston. A small metal cylinder about one inch by three-quarters is geared to a counter. The cylinder turns about its horizontal axis, and a small metal disc bears against the cylinder. The plane of the disc coincides with the axis of the cylinder and is turned by the motion of the indicator piston. The motion of the engine piston moves the cylinder horizontally. This combined action results in the rotation of the cylinder. The increment to rotation is proportional to the angle of the disc.
The manufacturer of this indicator is unknown. The spring is missing, although Thompson indicator springs will fit it. Similar instruments are described in William Robinson’s book Gas and Petroleum Engines: A Manual for Students and Engineers (Spon & Chamberlain, New York: 1902).
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illlinois, Urbana, Illinois
ID Number:
MC.316793
Catalog number:
316793
Accession number:
228496
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847277
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Trill Steam Engine Indicator

view Trill Steam Engine Indicator digital asset: Trill Steam Engine Indicator
Measurements:
overall: 10 1/2 in x 9 1/4 in x 4 1/4 in; 26.67 cm x 23.495 cm x 10.795 cm
Object Name:
indicator, steam engine
Place made:
United States: Connecticut
Description:
The Trill Indicator Co. manufactured this steam engine indicator. It consists of a brass piston with three grooves; a brass cylinder which is open at top; an external spring, which can be changed, but which is missing; a large drum with a spiral spring and a single record; and a brass stylus.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Yale University, Mason Laboratory, New Haven, Connecticut
ID Number:
MC.319488
Catalog number:
319488
Accession number:
237917
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847426

Schaeffer & Budenberg Steam Engine Indicator

view Schaeffer & Budenberg Steam Engine Indicator digital asset: Schaeffer & Budenberg Steam Engine Indicator
Physical Description:
aluminum (overall material)
Measurements:
overall: 7 3/4 in x 4 3/4 in x 2 7/8 in; 19.685 cm x 12.065 cm x 7.3025 cm
Object Name:
indicator, steam engine
Place made:
United States: Connecticut
Description:
Schaeffer and Budenberg manufactured this steam engine indicator, serial number 11059. It consists of a large steel piston with two grooves; a brass cylinder and aluminum body; an internal spring, which is missing; a light aluminum drum with a spiral spring and a single record; and a brass stylus.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Yale University, Mason Laboratory, New Haven, Connecticut
ID Number:
MC.319487
Catalog number:
319487
Accession number:
237917
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847427

Crosby Steam Engine Indicator

view Crosby Steam Engine Indicator digital asset: Crosby Steam Engine Indicator
Maker:
Crosby Steam Gage & Valve Company
Physical Description:
wood (container material)
Measurements:
overall: 5 3/4 in x 10 in x 8 1/2 in; 14.605 cm x 25.4 cm x 21.59 cm
walnut case - from catalog card: 5 3/4 in x 7 3/4 in x 10 in; 14.605 cm x 19.685 cm x 25.4 cm
Object Name:
indicator, steam engine
Place made:
United States: Massachusetts
Description:
Crosby Steam Gauge & Valve Co. of Boston, Massachusetts, manufactured this steam engine indicator, serial number 1074D. It consists of a steel piston; a vented brass cylinder; an external, double wound spring, which can be changed; a large drum with a spiral spring and a single record; and a brass stylus. Accompanying the indicator is a box with twelve springs and some small tools.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Department of Mechanical Engineering, University of Illinois, Urbana, Illinois
ID Number:
MC.316797
Catalog number:
316797
Accession number:
228496
Patent number:
1074D
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_1376104
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Tabor-Ashcroft Steam Engine Indicator

view Tabor-Ashcroft Steam Engine Indicator digital asset: Tabor-Ashcroft Steam Engine Indicator
Maker:
Ashcroft Mfg. Co.
Measurements:
overall: 9 7/8 in x 5 1/4 in x 2 in; 25.0825 cm x 13.335 cm x 5.08 cm
Object Name:
indicator, steam engine
Place made:
United States: Connecticut, Bridgeport
Date made:
ca 1878
Description:
Ashcroft Mfg. Co. of Bridgeport, Connecticut, manufactured this Tabor steam engine indicator, serial number 1624. It consists of a steel piston with a spherical guide below the spring; a vented brass cylinder; an internal, single wound spring, which can be changed; a large drum with a coil spring and a single record; and a conical brass stylus. The spring is missing.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Yale University, Mason Laboratory, New Haven, Connecticut
ID Number:
MC.319485
Catalog number:
319485
Accession number:
237917
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847429

Steam Engine Indicator

view Steam Engine Indicator digital asset: Steam Engine Indicator
Physical Description:
brass (overall material)
steel (overall material)
wood (container material)
Measurements:
overall: 5 in x 12 in x 9 in; 12.7 cm x 30.48 cm x 22.86 cm
Object Name:
indicator, steam engine
Description:
This steam engine indicator consists of a steel piston with three grooves, which can be changed; a vented steel cylinder; an external, double wound spring, which can be changed; and a brass stylus. The drum assembly is missing. Accompanying the indicator is a box with two extra pistons and liners, seven extra springs, and one turn cock.
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift from Estate of Kalman J. Dejuhasz, State College, Pennsylvania
ID Number:
1981.0217.12
Accession number:
1981.0217
Catalog number:
1981.0217.12
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_847458
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Hospitalier-Carpentier Manographe

view Hospitalier-Carpentier Manographe digital asset number 1
Physical Description:
wood (overall material)
glass (overall material)
brass (overall material)
Measurements:
overall - manograph: 5 in x 6 in x 6 in; 12.7 cm x 15.24 cm x 15.24 cm
overall - box: 4 7/8 in x 13 7/8 in x 10 1/2 in; 12.3825 cm x 35.2425 cm x 26.67 cm
Object Name:
manographe
Description:
This manographe, or indicator, was purchased by Professor W. H. Kenerson around 1907. He used it in making tests of the Brayton Oil Engine, National Museum of American History catalog number 313.703, at Brown University.
A pivoted mirror reflects a beam of light to a photosensitive plate or paper. Changes in pressure in the engine cylinder cause the mirror to oscillate up and down; a pin and eccentric actuated by a flexible shaft connected to the engine shaft cause the mirror to oscillate from side to side.
The indicator is housed in a wooden box that is 5 inches by 6 inches by 14 inches, with a brass pipe fitting and gear box at one end. The opposite end is open to receive a plate holder of a ground glass. A T-shaped tube lets light into one side, and an adjustable prism inside directs the light to the mirror. The flexible shaft is 32 inches long and covered with black fabric. Four plate holders, one ground glass, a steel petcock and a tapered hollow steel plug are included with the instrument. It is marked “Manographe Hospitalier-Carpentier, Brevete, S G D G, J. Carpentier, Paris.”
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
A mechanical indicator consists of a piston, spring, stylus, and recording system. The gas pressure of the cylinder deflects the piston and pushes against the spring, creating a linear relationship between the gas pressure and the deflection of the piston against the spring. The deflection is recorded by the stylus on a rotating drum that is connected to the piston. Most indicators incorporate a mechanical linkage to amplify the movement of the piston to increase the scale of the record.
When the ratio of the frequency of the pressure variation to the natural frequency of the system is small, then the dynamic deflection is equal to the static deflection. To design a system with a high natural frequency, the mass of the piston, spring, stylus, and mechanical linkage must be small, but the stiffness of the spring must be high. The indicator is subjected to high temperatures and pressures and rapid oscillations, imposing a limitation on the reduction in mass. Too stiff a spring will result in a small displacement of the indicator piston and a record too small to measure with accuracy. Multiplication of the displacement will introduce mechanical ad dynamic errors.
The parameters of the problem for designing an accurate and trouble free recorder are such that there is no easy or simple solution. Studying the variety of indicators in the collection shows how different inventors made different compromises in their designs.
Location:
Currently not on view
Credit Line:
Gift of Estate of Kalman J. Dejuhasz, State College, Pennsylvania
ID Number:
1981.0217.24
Accession number:
1981.0217
Catalog number:
1981.0217.24
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Data Source:
National Museum of American History, Kenneth E. Behring Center
EDAN-URL:
edanmdm:nmah_846681

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