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US1185944A - Pressure-control system. - Google Patents

Pressure-control system. Download PDF

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Publication number
US1185944A
US1185944A US34182806A US1906341828A US1185944A US 1185944 A US1185944 A US 1185944A US 34182806 A US34182806 A US 34182806A US 1906341828 A US1906341828 A US 1906341828A US 1185944 A US1185944 A US 1185944A
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pump
reservoir
pressure
reservoirs
motor
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US34182806A
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George B Schley
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Allis Chalmers Corp
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Allis Chalmers Corp
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Priority to US34182806A priority Critical patent/US1185944A/en
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/02Stopping, starting, unloading or idling control

Definitions

  • GEORGE B SGHLEY, or Nortwooi
  • OHIO AssIGNon
  • IBY MEs'NE ASSIGNMENTS 'ro ALLIS- CHALMERS MANUFACTURING COMPANY
  • a conronArroN OF DELAWARE A conronArroN OF DELAWARE.
  • My present invention has for its object to produce an improved fluid pressure system comprising a plurality of reservoirs, a single pump, means for driving the pum andcontrol devices responsive to the flui pressure in the reservoirs.
  • my invention con sists of the combinationof a pump driven by an electric motor, a plurallty ofv reservoirs, a pressure switch connected to each reservoir, and electrical connections whereby the motor circuit is completed when any of sald switches is-closed.
  • my invention consists of a fluid pressure system comprising a pump, a motor for driving the pump, a
  • the motor 10 is mechanically connected to an air pump 11.
  • the outlet side of. the pump may be connected either through an openlng 12 to the atmosphere as .shown, or to a reservoir 13 for compressed air. From this reservoir 13 compressed air can be drawn for-any desired purpose through. a pipe 14.
  • a check valve 15 prevents any backward flow of the air from the reservoir 13 to or through the valve 12.
  • lhe intake side of the pump 11 may be connected by' a valve 16 either through an opening 16 to the atmosphere as shown, or to a reservoir- 1'?v for rarefied air or a partlal vacuum.
  • the reservoir 17 may be connected by'mea'ns of a pipe 18 to any desired apparatus from-which air is to be withdrawn.
  • a check valve 19 prevents any backward flow of air through the valve 16 into thereservoir 17.. Both the ntake and the outlet of the pump 11 are normally connected to the atmosphere.
  • a pressure switch 20 preferably an adjustable snap switch
  • the switch is'responsiveto the pressure in thereservoir 13' andcloses when the pressure in sald reservoir decreases below a predetermined minimumand'opens when said pressure rises above a predetermined maximum.
  • this switch 7 completes the circuitof the motor 10 from the trolleywire 21 to the trolley 22, switch 20,. solenoid 23, motor field winding '24, and
  • solenoid 23 when energized moves its core 25 against the spring 26 to operate the valve 12 to connect the outlet of the pump 11 to the reservoir 13.
  • the solenoid 28 when energized moves its core 29 against the spring 30 to operate the valve 16 to connect the reservoir 17 to the intake of the pump 11.
  • the pressure switch 27 opens when the pressure inthe -reservoir 17 is reduced to a predetermined minimum. :
  • switches 20 and 27 together with the solenoids 23 and 28 respectively are in shunt to each other between the trolley 22 and the motor field winding 24. When either one of these'switches is closed the motor will operate to drive the pump 11. p
  • the pump will work onsaid reservoirs, either supplying or exhausting, until the pressure in the reservoir whose normal pressure is nearest atmospheric hasbeen brought to the desired normal value, at which time this reservoir will be disconnected from the pump through the actuation of its valve 12 or 16; and followingsuch'disconnection, the pressure in that one of the remaining reservoirs whose normal pressure is next nearest to atmospheric will be raised or lowered to the desired normal. value, and this reservoir will then be disconnected through the actuation of its corresponding valve 12 or 16. This operation will continue until the pressure in each reservoir is restored to normal.
  • My invention is equally applicable to any other fiuid pressure systems whether gaseous or liquid, and is not limited to air pressure systems.
  • a fluid pressure system comprising a pump, a motor for driving said pump, a plurality of reservoirs, and means governed. by
  • a fluid pressure system comprising an electric motor, a pump driven thereby, a plurality of reservoirs, and means governed by the pressure in each reservoir forconnecting said reservoir to the pump whenever said pressure departs from its normal value and disconnecting said reservoir from the pump when said pressure is restored to its normal value, and for completing themotor circuit whenany reservoir is connected-to the pump.
  • the combi- 'su re devices respectively responsive to the pressure in thetwo reservoirs for controlling the electrical connections of the motornation of an air pump, a motor for driving said pump, two reservoirs, and a fluidpressure device responsive to the 'pressure'in' each reservoir, one to control the pneumatic connection between its reservoir and the outlet side of the pump and the other'to control the pneumatic connection between its reservoinand the intake side of the pump, and both of said devices controlling the operation of the pump-driving motor.
  • a fluid pressure system the combinationof an electric motor, an air pump driven thereby, two reservoirs, and a fluid pressure device responsive to the pressure in'each reservoir, -one to control the pneu-- v matic connection between its reservoir and q the outlet side of the pump and the other to control thepneumatic iconnection between its reservoir and theintake side of the pump, and each contr olling the motor circuit.
  • valve for connectin the outlet side of the pump to the other ressrvoir or to *th tmo i phere, and means for automatically controlling said valves and the circuit of the mo tor in response to thepressures in the reservoirs.
  • valve for connecting the outlet side of the pump to the other reservoir or tothe atmosphere, and fluid pressure responsive devices for automatically controlling said valves respectively in response to the pressures in the two reservoirs respectively and-for also controlling the motor circuit.
  • a fluid pressure system comprising an electric 'motor, a pump driven thereby, two
  • a fluid pressure system comprising an pressure in each reservoinsaid switches all being in the motor circuit "and I 1ndepend- :ently controlling the motor; 155; .
  • a fluid pressure system comprising an electric motor, a pump driven thereby, a

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Positive-Displacement Pumps (AREA)

Description

G. B. SCHLEY.
PRESSURE CONTROL'SYSTEM. APPLICATION FILED NOV. 3. 1906.
1,1 85,944, I I Y Patenfed June 6, 1916.
Ugo
GEORGE B. SGHLEY, or Nortwooi), OHIO, AssIGNon, IBY MEs'NE ASSIGNMENTS, 'ro ALLIS- CHALMERS MANUFACTURING COMPANY, A conronArroN OF DELAWARE.
. k PRESSURE- CONTROL SYSTEM. f
Specification of Letters Patent. Patented 3 6, 1916,
Application filed November 3, 1906. Seria1 No. 341 ,828.
To all whom it concern.
Be it known that LGEoRoE B. SoHLEY, a
citizen of the United States, residing at NOT", Wood, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Pressure-Control Systems, of which the following is a full, clear, and exact sp cification.
My invent on relates to pressure control systems.
In some systems where fluid pressure is used it is desirable that a number of difi'erent pressures-be obtainable; Very'often. it is desirable not to attempt to obtain these diiierent pressures from a source of highest pressure by means of pressure reducing valves, but to obtain'each pressure from a separate reservolr supplled' directly by a pump. However, if each reservolr has a separate pump the expense of installing the system is unduly great, and as the pumps, would then work only-part of the time,
much of the time the investment would be idle. But as each reservoir needs a pump but part of the time it would be advantageous to havethe same pump .for a number of reservoirs so that it would restore the proper pressure in one reservoir when not operatively connected to another. And by proper arrangements the same pump can simultaneously restore di'fl'erent pressures in a plurality of reservoirs.
' My present invention has for its object to produce an improved fluid pressure system comprising a plurality of reservoirs, a single pump, means for driving the pum andcontrol devices responsive to the flui pressure in the reservoirs.
In the specific'embodiment of my invention which is here illustrated are shown two reservoirs, one for compressed air and one for rarefied air, and a single pump driven by an electric motor, together with electric and penumatic connections so arranged that the pump will operate whenever the condition of fluid in either reservoir demands it and that reservoir will then be connected to the outlet or intake of the pump as the case may be. With this arrangement two different predetermined pressures are obtainable.
In one broad aspect my invention con sists of the combinationof a pump driven by an electric motor, a plurallty ofv reservoirs, a pressure switch connected to each reservoir, and electrical connections whereby the motor circuit is completed when any of sald switches is-closed.
In another broad aspect my invention consists of a fluid pressure system comprising a pump, a motor for driving the pump, a
plurality of reservoirs, and means governed by the pressure in each reservoir for c0n-- necting said-reservoir to the pump whenever appear from the description and drawings and will be claims.
The single figure of the drawings repreparticularlyt-pointed out in the sents diagrammatically one embodiment of my invention.
In this figure the motor 10 is mechanically connected to an air pump 11.- By means of a valve 12 the outlet side of. the pump may be connected either through an openlng 12 to the atmosphere as .shown, or to a reservoir 13 for compressed air. From this reservoir 13 compressed air can be drawn for-any desired purpose through. a pipe 14. A check valve 15 prevents any backward flow of the air from the reservoir 13 to or through the valve 12. lhe intake side of the pump 11 may be connected by' a valve 16 either through an opening 16 to the atmosphere as shown, or to a reservoir- 1'?v for rarefied air or a partlal vacuum. The reservoir 17 may be connected by'mea'ns of a pipe 18 to any desired apparatus from-which air is to be withdrawn. A check valve 19 prevents any backward flow of air through the valve 16 into thereservoir 17.. Both the ntake and the outlet of the pump 11 are normally connected to the atmosphere.
. Connected to thereservoir 13 1s a pressure switch 20, preferably an adjustable snap switch, The switch is'responsiveto the pressure in thereservoir 13' andcloses when the pressure in sald reservoir decreases below a predetermined minimumand'opens when said pressure rises above a predetermined maximum. When closed this switch 7 completes the circuitof the motor 10 from the trolleywire 21 to the trolley 22, switch 20,. solenoid 23, motor field winding '24, and
motor armature IO-Qto the ground. The
solenoid 23 when energized moves its core 25 against the spring 26 to operate the valve 12 to connect the outlet of the pump 11 to the reservoir 13. 1 p v. Connected to the reservoir 17 is a pressure switch 27, also preferably an adjustable snap switch. This switch closes when the pressurevin the reservoir 17 exceeds a prede= termined maximum, thus completing the motor circuit from the trolley 22 through the switch 27 solenoid 28, motor field winding 24, and motor armature 10 to ground. The solenoid 28 when energized moves its core 29 against the spring 30 to operate the valve 16 to connect the reservoir 17 to the intake of the pump 11. The pressure switch 27 opens when the pressure inthe -reservoir 17 is reduced to a predetermined minimum. :The
switches 20 and 27 together with the solenoids 23 and 28 respectively are in shunt to each other between the trolley 22 and the motor field winding 24. When either one of these'switches is closed the motor will operate to drive the pump 11. p
The operation of the system is as follows 7 When the pressures in both reservoirs 13 and 17 are within the predetermined limits for which the switches 20 and 27 are set, the parts are as shown in the drawing, with the motor and pump at rest and the intake and outlet of the pump both connected to the at mosphere. Should the pressure in reservoir 13 fall below its lower limit the switch 20,
- will close to complete the motor circuit and motor 'cir'cuit'and allow the spring 26 to operate the valve 12 to disconnect the outlet of the pump 11 from the reservoir 13 and connect it to the atmosphere.
Sh uldthe pressure in the reservoir 17 rise above the predetermined maximum for which the switch 27 is set, the said switch 27 will close to complete'the motor circuit and to. cause the valve 16 to be operated to con. meet the reservoir 17 .to' the intake of the f pump 11.1 lhe pump llwill now be oper- "flee.
' and connect it to the atmosphere.
Should both-the switches 20 and 27 Q ated by .the motor 10 toexhaust air. from the its reservoir 17, to the atmosphere, the switch 20 being open. v'lfhis'continues until the pres sure'in reservoir 17 reaches the desired minimum,whenthe=switch 27 will open to break the motor :circuit'and allow the spring 30 to s Q op'erate fthe-valve 16' to disconnect, the intake'of the pump 11 from the reservoir 17 closed simultaneously because the pressure reservoir 13 falls too low andthat in resineaeaa ervoir 17 rises too high, the motor will operate the pump to exhaust the air from the reservoir 17 and supply it'to the reservoir 13. At this time both the valves 12 and 16 from the pump, but the pump will not cease to operate until both switches 20 and 27 have opened, at which time the respective pressures in the two reservoirs will be those de sired.
Although I have shown my invention as applied to a combined'vacuum and compression system, it is not limited to such. There may be any desired number of reservoirs with their independent pressure switches and valvescorresponding to'the switches 20 and 27 and the valves 12 and 16 upon either the compression or the vacuum side of the system, with the switches for the difi'erent reservoirs set for difl'erentpressures. With such an arrangement in case two or more reservoirs are simultaneously connected to the same side of the .pump through'the operation of the corresponding valves 12 or 16, the pump will work onsaid reservoirs, either supplying or exhausting, until the pressure in the reservoir whose normal pressure is nearest atmospheric hasbeen brought to the desired normal value, at which time this reservoir will be disconnected from the pump through the actuation of its valve 12 or 16; and followingsuch'disconnection, the pressure in that one of the remaining reservoirs whose normal pressure is next nearest to atmospheric will be raised or lowered to the desired normal. value, and this reservoir will then be disconnected through the actuation of its corresponding valve 12 or 16. This operation will continue until the pressure in each reservoir is restored to normal.
I have shown and described my invention as applied to an electric railway car, but obviously it is not limited to such use but maybe used in any place where a pluralitiy of different fluid pressures are desired; neither'is it limited to the use of an electric viously, any suitable type of motor or prime mover may be used for operating the pump.
My invention is equally applicable to any other fiuid pressure systems whether gaseous or liquid, and is not limited to air pressure systems. a
Many other. modifications can also be made and in the following claims I aim to cover all such which do not involve a departure from the spirit and scope of my invention.
' What I claim as new and desire to secure by Letters Patent is N 1. A fluid pressure system, comprising a pump, a motor for driving said pump, a plurality of reservoirs, and means governed. by
. the pressure in each reservoir for connectmg said reservoir to the: pump and effect ing the starting of the pump-driving motor whenever said pressure departs from its normal value and disconnecting said reser-' voir from the pump and effecting the stopping of the pump-driving motor when said pressure is restored to its normal value.
2. A fluid pressure system,comprising an electric motor, a pump driven thereby, a plurality of reservoirs, and means governed by the pressure in each reservoir forconnecting said reservoir to the pump whenever said pressure departs from its normal value and disconnecting said reservoir from the pump when said pressure is restored to its normal value, and for completing themotor circuit whenany reservoir is connected-to the pump.
3. In a fluid pressure system, the combination of an electric motor, a pump driven thereby, a plurality of reservoirs, and a fluid pressure governed. device for each res ervoir for controlling the current supply to the motor and the connection between that reservoir and the pump. i. In a fluid pressure system, the combination of an electric motor, an air pump driven thereby, a plurality of reservoirs,
and a pressure switch responsive to the pressure in each reservoirto control the electrical connections of the motorand the pneumati'c connections of that reservoir to the pump.
In a fluid pressure system, the combination of an electric motpr, an air pump t driven thereby, two reservo1rs,a switch responsive to the -extent of rarefaction in one reservoir, a second switch responsive to the driven thereby, two reservoirs, a switch responsive to the extent of rarefaction in' one 5 reservoir, a second switch responsive to the pressure in the other reservoir, and electri cal connections whereby said switches simultaneously control the motor. circuit.
7. In a fluid pressure system, the combination of an air pump, means for driving said pump, a compressed air reservoir, a rarefied air reservoir, and two fluid pressure devices for controlling the pneumatic connections between the two reservoirs respectively and the pump and for controlling the operation of means.
8. In a fluid pressure system, the combination of an electric motor, .an air pump driveifthereby, a compressed air. reservoir, a rarefied air reservoir, and two fluid p reselectric'motor, a pump plurality OfI'GSGIVOlI'S associated. with the the pump dr iving pump, and a pressure switch responsive to the and the pneumatic connections between the pump and the, two reservoirs respectively.
9. In a fluid pressure system, the combi- 'su re devices respectively responsive to the pressure in thetwo reservoirs for controlling the electrical connections of the motornation of an air pump, a motor for driving said pump, two reservoirs, and a fluidpressure device responsive to the 'pressure'in' each reservoir, one to control the pneumatic connection between its reservoir and the outlet side of the pump and the other'to control the pneumatic connection between its reservoinand the intake side of the pump, and both of said devices controlling the operation of the pump-driving motor.
' 10. In a fluid pressure system, the combinationof an electric motor, an air pump driven thereby, two reservoirs, and a fluid pressure device responsive to the pressure in'each reservoir, -one to control the pneu-- v matic connection between its reservoir and q the outlet side of the pump and the other to control thepneumatic iconnection between its reservoir and theintake side of the pump, and each contr olling the motor circuit.
11. In a fluid pressure system, the combination of anelectric motor, an air pump driven thereby, two reservoirs, a valve for connectingthe intake side of the pump to one of the reservoirs or to the atmosphere,
a valve for connectin the outlet side of the pump to the other ressrvoir or to *th tmo i phere, and means for automatically controlling said valves and the circuit of the mo tor in response to thepressures in the reservoirs.
12. In a fluid pressure system, the combination of an electric motor, an air pump driven thereby, two reservoirs, a valve for yconnecting the intake side of the pump to one of thereservoirs or to the atmosphere, v
- a valve for connecting the outlet side of the pump to the other reservoir or tothe atmosphere, and fluid pressure responsive devices for automatically controlling said valves respectively in response to the pressures in the two reservoirs respectively and-for also controlling the motor circuit.-
13. A fluid pressure system,comprising an electric 'motor, a pump driven thereby, two
reservoirs, and two pressure switches ref sponsive to the pressure in the two reservoirs respectively, said switches being in shunt to each other and in the motor circuit. 1
14. A fluid pressure system, comprising an pressure in each reservoinsaid switches all being in the motor circuit "and I 1ndepend- :ently controlling the motor; 155; .A fluid pressure system, comprising an electric motor, a pump driven thereby, a
driven thereby, a l
plurality of reservoirs, and a'pressure switch responsive-to the pressure in each reservoir,
said switches all being in the motor circuit and in shunt to each other.
16. In combination, an electric motor, a
pump driven thereby, two reservoirs, a pres sure switch connected to each reservoir, and electrical connections whereby the motor circuit is completed when either switch is closed.
17. In combination, an electric motor, a pump driven thereby, two reservoirs, a pressure switch connected to each reservoir,
electrical connections whereby the motor circuit is completed when either switch is closed, and means for connecting one ofthe pump driven thereby, two reservoirs, a pressure switch connected to each reservoir, electrical connections whereby the motor circuit is completed when either switch is closed, and means for connecting the reservoirs to the intake and the outlet of the pump respectively when their respective associated switches are closed.
20. In combination, an electric motor,a
4 pump driven thereby, two reservoirs, a pressure switch connected to each reservoir, electrical connections whereby the motor circuit and means for connecting the reservoirs to the pump when their respective switches are closed.
21. In combination, an electric motor, a 7
pump driven thereby, a plurality of reservoirs, a pressure switch connectedto each reservoir, electrical connections whereby the motor circuit is completed when any switch is closed, and means for connecting the reservoirs to the pump when their respective switches are closed.
22. In a combined pressure and vacuum system, the combination of a pressure reservoir, a vacuum reservoir, a pump, a motor for driving said pump, and means responsive to the pressures in said reservoirs for causing the starting or stopping of said motor and the consequent operation or discontinuation ofoper'ation of said pump and the connection of one or the other of said reservoirs. to said pump or the disconnection thereof.
23. In a fluid pressure system, the combitions between the pump and the corresponding reservoir. v
In testimony whereof I afix my signature,
' in the-presence of two witnesses.
GEORGE E. sonLnY;
Witnesses:
VIc'roR E. JnLLmN, ARTHUR F. Kwis.
- nation of a pump, means for driving said
US34182806A 1906-11-03 1906-11-03 Pressure-control system. Expired - Lifetime US1185944A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2492075A (en) * 1945-10-30 1949-12-20 Kinney Mfg Company Vacuum pump
US2509816A (en) * 1945-04-19 1950-05-30 Clyde C Elson Brake testing apparatus
US2511494A (en) * 1945-11-23 1950-06-13 Cohen Abraham Gaseous compressing system
US2626229A (en) * 1948-10-22 1953-01-20 Carl F Miller Apparatus for refining used lubricating oil
US2743395A (en) * 1952-02-28 1956-04-24 Westinghouse Electric Corp Protective system for series capacitors
US2973632A (en) * 1957-11-08 1961-03-07 Engineering And Res Lab Servic Portable refrigerated cooler

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2509816A (en) * 1945-04-19 1950-05-30 Clyde C Elson Brake testing apparatus
US2492075A (en) * 1945-10-30 1949-12-20 Kinney Mfg Company Vacuum pump
US2511494A (en) * 1945-11-23 1950-06-13 Cohen Abraham Gaseous compressing system
US2626229A (en) * 1948-10-22 1953-01-20 Carl F Miller Apparatus for refining used lubricating oil
US2743395A (en) * 1952-02-28 1956-04-24 Westinghouse Electric Corp Protective system for series capacitors
US2973632A (en) * 1957-11-08 1961-03-07 Engineering And Res Lab Servic Portable refrigerated cooler

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