US1264422A - Control apparatus. - Google Patents

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US1264422A
US1264422A US85883114A US1914858831A US1264422A US 1264422 A US1264422 A US 1264422A US 85883114 A US85883114 A US 85883114A US 1914858831 A US1914858831 A US 1914858831A US 1264422 A US1264422 A US 1264422A
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pistons
cylinder
fluid
piston
movement
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US85883114A
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Ferdinand G Moard
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CBS Corp
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Westinghouse Electric and Manufacturing Co
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/08Servomotor systems incorporating electrically operated control means

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  • My invention relates to control apparatus, and it has specialreference to means for controlling the operation of a movable member, such as a controller for electric circuits or the like.
  • the object-of my invention is to provide a device of the above-indicated character, the movement of which may be readily and quickly arrested at any desired point, and
  • I provide a plurality of pistons which operate in a suitable cylinder andare' operatively connected to anelectrical controller or other member to be actuated, in combination with means for admitting fluid-pressure to each end of the cylinder to move the member to be actuated in the one or the other direction, and independent means for admitting fluid pressure between oneof the end pistons and an intermediate piston for causing the pis-v ton washers or rings to immediately frictionally lock the pistons in position.
  • a prompt arrest of movement of the member at any desired point, may be secured.
  • the single figure is a view, partially in section and partially in. elevation, of a control apparatus constructed in accordance with my invention, combined with an electrical system, which is shown diagrammatically, for governing the operation of the structure shown.
  • the apparatus here illustrated comprises a suitable incasing member or operating cylinder 1 which is provided with end caps 1; a pair of pistons 2 and 3 which are located near the respective ends of the cylinder 1, and an intermediate piston 4, all of the pistons being mounted on a common rod or stem' 5; a suitable lever 6 for operatively connect ing the piston to a device 7 to be actuated, which device is shown in the drawingas Specification of Letters Patent.
  • a resistor 7 cludes a resistor 7 .
  • the pistons 3 and'et are respectively provided, on their adjacent faces, with flexible washers or piston rings 1 1 which have relatively large bearing surfaces within the cyliqncer 1, for a purpose to be hereinafter speci-
  • the magnet valve 8 is of a familiar type and comprises essentially a magnet coil 15 whichi is adapted, when energized, to actua suitable valve member 17.
  • valve 9 When the valve is closed, as shown in the the atmosphere through an inlet or port 18; and, when the valve is energized, fluid pressure is admitted from the source 11. through pipes 19 and 20 to an inlet passage 21 within the corresponding end cap 1.
  • the magnet valve 9 is of similar construction, being pr vided with anoutlet port 22 and an inlet passage 23 to which fluid-pressure is admittedfrom the pipes 19 and 24: when the valve is energized.
  • the valves 8 and 9 will hereinafter be referred to as standard v.-- ves.
  • hemagnet valve 10 is normally deenergized and open to admit fluid-pressure from the source 11 through pipes 25 and 26 to the chamber 27 between the pistons 3 and 4, thereby causing the washers 14 to tightly grip the inside walls of the cylinder 1.
  • fluid pressure is exhausted from the chamber 27 through pipe 26 and outlet port 26
  • the valve 10 will hereinafter be spoken of as an invertedvalve.
  • a fluid-actuator comprising a plurality of pistons, a cylinder in which the pistons operate, means for controllingthefluid pressure in each end of thecylinder to produce a movementof thepistons in the one or the other direction, the fluid pressure between the tard said movement.
  • A'fiuid a'ctuator comprising a-plurality of pistons, a. cylinder in which the pistons pistons to reoperate, means for unbalancing the fluid pressures in the ends of the cylinder to pro Jerusalem a movement of the pistons in the one or the other direction, and means for admitting operating fluid between the pistons to arrest said movement.
  • a fluid-actuator comprising a plurality of pistons, a cylinder in which the pistons operate, normally closed magnet-ac- 7 tuated valves energized through said switch- ,ing device to admit fluid pressure to the respective ends of the cylinder for producing pistons in the one or the other direction, and another magnet-actw ated valve energized when the switching device is closed to exclude fluid pressure from pistons and'denergized at other pistons to arrest-"said movement.
  • a fluid-actuator comprisingapiston a.
  • auxiliary fluid-pressure controlled means rigidly secured to the piston for locking it in any predetermined position.
  • a fluid actuator comprising a pluralitv of pistons, a cylinder in which the pistons operate, means for controlling the fluid-pressure in each end of the cylinder to produce a movement of the pistons in the one or the other direction, an auxiliary chamber intermediate the pistons, and means for controlling the fluid pressure'in said chamber to lock the pistons in any predetermined position.
  • a fluid actuator comprising a plurality of associated pistons, a cylinder in which the pistons operate, means for. controlling the fluid pressure in each end of the cylinder to produce a movement of the pistons in the one or the other direction, another piston disposed intermediate the firstname-J pistons and associated therewith, and means for admitting fluid said intermediate piston an one of the other pistons to lock the associated pistons in any predetermined position.
  • a fluid-actuator comprising a piston
  • a fluid-actuator comprising a piston, a cylinder in which the piston operates,
  • piston to produce a movement in the one or the other direction, another piston disposed intermediate the first named pistons, and means for causing a frictional engagement of said intermediate piston and another piston within the cylinder to arrest said movement.
  • a fluid-actuated means comprising a plurality of pistons, a cylinder in which the pistons operate, means for controlling the the outer side of each piston to produce a movement in the one or the other direction, an intermediate piston, disposed" near one of the first named pistons and movable therewith, and auxiliary means 'for admitting: fluid pressure between said intermediate piston and the nearer of the first-named pistons to cause a frictional lockin of the two pistons within the cylinder, w ereby said pistons are held in any predetermined position.
  • a fluid-actuated means comprising a pair of p istons,a-cylinder in which the pistons operate, normally closedelectromagnetically actuated valves for controlling the sressure'in each end of the cylinder to pro- 5 ucei a movement of the member in the one :'or the other direction, an. intermediate pisexclude fluidpressure from they chamber 'ineluded between said intermediate piston and the nearer of the first-named pistons during said movement giization,-to admit fluid pressure into said chamber to cause a frictional locking of the two pistons Within the vcylinder, whereby the pistons are held'in any predetermined position.
  • the combination ing cylinder anda plurality of associated pistons disposed therein, .of means for admitting relatively high-pressure operating.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Actuator (AREA)

Description

F. G. MOARD. CONTROL APPARATUS." APPLICATION FILED AUG-2?. I914- Patented Apr. 30, 1918.
M 81 M Q 0 H 6 7 a 2 9 1 Q w 4 1 a WITNESSES:
UNITED STATES PATENT OFFICE.
FERDINAND e. MOARD, or TURTLE CREEK, PENNSYLVANIA, ASSIGNOR TO WESTING HOUSE ELECTRIC AND MANUFACTURING coMPANY, A CORPORATION or PENNSYL- VANIA.
CONTROL APPARATUS.
To all whom it may concern:
Be it known that 1,.FERDINAND G.=.LV.| OARD, a citizen of the United States, and a resident of Turtle Creek, in the county of Allegheny and State of Pennsylvania, have invented a-new and useful. Improvement in Control Apparatus, of which the following is a specification.
My invention relates to control apparatus, and it has specialreference to means for controlling the operation of a movable member, such as a controller for electric circuits or the like.
The object-of my invention is to provide a device of the above-indicated character, the movement of which may be readily and quickly arrested at any desired point, and
wherein no tendency to overshooting any predetermined position is encountered, which tendency is found in some prior types of control apparatus of the class above indicated.
..- lccording to my invention, I provide a plurality of pistons which operate in a suitable cylinder andare' operatively connected to anelectrical controller or other member to be actuated, in combination with means for admitting fluid-pressure to each end of the cylinder to move the member to be actuated in the one or the other direction, and independent means for admitting fluid pressure between oneof the end pistons and an intermediate piston for causing the pis-v ton washers or rings to immediately frictionally lock the pistons in position. Thus, a prompt arrest of movement of the member, at any desired point, may be secured.
In the accompanying drawing, the single figure is a view, partially in section and partially in. elevation, of a control apparatus constructed in accordance with my invention, combined with an electrical system, which is shown diagrammatically, for governing the operation of the structure shown. Referring to the drawing, the apparatus here illustrated comprises a suitable incasing member or operating cylinder 1 which is provided with end caps 1; a pair of pistons 2 and 3 which are located near the respective ends of the cylinder 1, and an intermediate piston 4, all of the pistons being mounted on a common rod or stem' 5; a suitable lever 6 for operatively connect ing the piston to a device 7 to be actuated, which device is shown in the drawingas Specification of Letters Patent.
a conventional electrical controller that is Patented Apr. 30, 1918. Application filed August 27,1914. Serial No. 858,831.
cludes a resistor 7 .a pair of magnet valves 8 and 9 that are associated with the respective ends of the cylinder 1; a third magnet valve 10 of slightly-different construc tion'; a source of fluid pressure 11 for sup plying fluid pressure to the several magnet valves, a master controller'12 for governing the electrical operation of the magnet valves and adapted to assume a position 7", in one direction, a position 1', in the opposite direction, and an intermediate off position;
and a sourceof electrical energy 13 that is suitably associated with the controller 12.
The pistons 3 and'et are respectively provided, on their adjacent faces, with flexible washers or piston rings 1 1 which have relatively large bearing surfaces within the cyliqncer 1, for a purpose to be hereinafter speci- The magnet valve 8 is of a familiar type and comprises essentially a magnet coil 15 whichi is adapted, when energized, to actua suitable valve member 17.
When the valve is closed, as shown in the the atmosphere through an inlet or port 18; and, when the valve is energized, fluid pressure is admitted from the source 11. through pipes 19 and 20 to an inlet passage 21 within the corresponding end cap 1. The magnet valve 9 is of similar construction, being pr vided with anoutlet port 22 and an inlet passage 23 to which fluid-pressure is admittedfrom the pipes 19 and 24: when the valve is energized. The valves 8 and 9 will hereinafter be referred to as standard v.-- ves.
hemagnet valve 10 is normally deenergized and open to admit fluid-pressure from the source 11 through pipes 25 and 26 to the chamber 27 between the pistons 3 and 4, thereby causing the washers 14 to tightly grip the inside walls of the cylinder 1. Upon the energization of the coil, fluid pressure is exhausted from the chamber 27 through pipe 26 and outlet port 26 The valve 10 will hereinafter be spoken of as an invertedvalve. The operation of my apparatus may be described as follows: Assuming the master "ate a magnet core member 16 for operating 5 net valves 9 and '10, respectively, whereby fluid pressure is admitted to the corresponding end of the cylinder 1 through the inlet 23 and is exhausted from the chamber 27 to actuate the pistons to the right and to radually exclude sections of'the resistor 5 from the circuit 7*, by the operation of the member 7 to its yarious operative positions. In order to arrest the movement of the member 7 at any desired point, the con troller 12 is returned to its oif position to deenergize the magnet valves 9 and 10,
whereupon, fluid pressure is admltted .to
the chamber 27 to cause the frictional engagement of the washers let with the inside walls of the cylinder 1 and innnediate stopping of the movement of the piston, The
member 7 may thus'be operated to one ex-' treme position, or it may be held in any predetermined position as long as desired. Toireturn the member 7 to its initial position, which is shown on the drawing, the controller 12 is thrown to its position 1", thereby causing the energization of the in-' vested valve magnet through the conductor 29 andiof the standardvalve magnet 8 through the conductor 30. Fluid pressure is thus admitted to the opposite end of the cylinder Land is exhausted from the chamber 27 to cause a movement of the pistons and the member 7 to the initial position. Such movement may, of course, be arrested at any point by the actuation of the master controller 12 to its ofl' position.
I do not wish to be restricted to the specific structural details or arrangement of parts herein set forth for illustrative purposes, as many modifications thereof may be made within the spiritand scope of m invention; and I desire that only such limitations shall be imposed as are indicated in the appended claims.
I laim as my invention:
. 1. A fluid-actuator comprising a plurality of pistons, a cylinder in which the pistons operate, means for controllingthefluid pressure in each end of thecylinder to produce a movementof thepistons in the one or the other direction, the fluid pressure between the tard said movement. p '2. A'fiuid a'ctuator comprising a-plurality of pistons, a. cylinder in which the pistons pistons to reoperate, means for unbalancing the fluid pressures in the ends of the cylinder to pro duce a movement of the pistons in the one or the other direction, and means for admitting operating fluid between the pistons to arrest said movement. v
3.- A 1 fluid-actuator comprising a plurality est pistons, a
and means for controlling movement of the betwen the times cylinder in which the pistons R 4. A fiuid-actuator comprising a plurality of pistons, a cylinder in which the pistons operate, valves for controlling the admis sion of fluid pressure to the respective ends of the cylinder, another valve for, controlling the admission of fluid pressure between the pistons, one of said valves being normally open and the others being normally closed, and means for actuating either end valve and the intermediate valve to produce a redetermined movement of the pistons-and for permitting said valves to return to their initial positions to hold said pistons in a predetermined posit-ion.
5.-A fluid-actuator comprising a plurality of pistons, a cylinder in which the pistons operate, electromagnetically actuated valves for controlling the admission of fluid pressure to the respective ends of the cylin der, and another valve for controlling the admission of fluid pressure between the pistons, one of said valves being closed When its actuating magnet is energized and the others being open when their actuating mag nets are energized.
6*. A fluid-actuatorcomprising a plurality of pistons,-a cylinder in whichthe pistons operate, magnet-actuated valves for c0ntrolling the supply of fluid pressure'to the respective ends of the cylinder; another magnet-actuated valve for controlling the supply of fluid pressure between the pistons, I s
vice, of a fluid-actuator comprising a plurality of pistons, a cylinder in which the pistons operate, normally closed magnet-ac- 7 tuated valves energized through said switch- ,ing device to admit fluid pressure to the respective ends of the cylinder for producing pistons in the one or the other direction, and another magnet-actw ated valve energized when the switching device is closed to exclude fluid pressure from pistons and'denergized at other pistons to arrest-"said movement.
-- 9. A fluid-actuator comprisingapiston a.
to admit fluid pressure between the means for controlling the fluid-pressure 1n each end of the cylinder to produce a movement of the piston in the one .or the other direction, and auxiliary fluid-pressure controlled means rigidly secured to the piston for locking it in any predetermined position.
11. A fluid-actuator comprising a piston, a cylinder in which the piston operates, means for controlling the fluid-pressure in each end of the cylinder to produce a movement of the piston in the one or the other i direction, an auxiliary chamber in the cylinder, and means sure in said chamber to lock the piston in for controlling the fluid presany predetermined position.
12.,A fluid actuator comprising a pluralitv of pistons, a cylinder in which the pistons operate, means for controlling the fluid-pressure in each end of the cylinder to produce a movement of the pistons in the one or the other direction, an auxiliary chamber intermediate the pistons, and means for controlling the fluid pressure'in said chamber to lock the pistons in any predetermined position.
13. A fluid actuator comprising a plurality of associated pistons, a cylinder in which the pistons operate, means for. controlling the fluid pressure in each end of the cylinder to produce a movement of the pistons in the one or the other direction, another piston disposed intermediate the firstname-J pistons and associated therewith, and means for admitting fluid said intermediate piston an one of the other pistons to lock the associated pistons in any predetermined position.
14. A fluid-actuator comprising a pair of pistons, a cylinder in which the pistons operate, electro-magnetically actuated. valves for controlling the fluid pressure in each end of the cylinder to produce a movement of the pistons in the one or the other direction, an intermediate piston disposed near one of the first named pistons and movable therewitln'and a .third electromagneticallyactuated valve for admitting fluid pressure between said intermediate piston and the nearer of the first-named pistons to lock the.
- pistons in any predetermined position.
actuated valves 15. A fluid-actuator comprising a pair of pistons, a cylinder in which the pistons operate, normally for controlling the pressure oi the cylinder to produce a ineach end the one or the movement of'the p'istons in other direction,
(pressure between fluid pressure on .closed electromagneticallyan intermediate piston disposed near one of the first-named pistons and 1 -movable therewith, and a normally open valv'e electromagnetically actuated to exclude fluid pressure from the chamber included between said intermediate piston and the nearer of the first-named pistons during said movement and adapted, upon deenergr zation, to admit fluid pressure into said chamber tolock the pistons in anypredetermined position.
16. A fluid-actuator, comprising a piston,
a cylinder in which the piston operates,
means for controlling the fluid-pressure in each end of the cylinder to produce a movement in the one or the other direction, and means for causing a frictional arresting of the piston in any predetermined position.
17. A fluid-actuator comprising a piston, a cylinder in which the piston operates,
' means for controlling the fluid pressure in each end of the cylinder to produce a movement in the one or the other direction, and fluid-pressure controlling means for causing a frictional engagement of the piston within the cylinder to arrest said movement.
18. A fluid-actuated means comprising a plurality of pistons, a cylinder in which the pistons operate, means for controlling the fluid pressure on the outer side of each piston to produce a movement in the one or the other direction, and auxiliary meansfor causing a-irictional engagement of the inner side of one of said pistons within-the cylinder for arresting said movement under predetermined conditions.
piston to produce a movement in the one or the other direction, another piston disposed intermediate the first named pistons, and means for causing a frictional engagement of said intermediate piston and another piston within the cylinder to arrest said movement.
20. A fluid-actuated means comprising a plurality of pistons, a cylinder in which the pistons operate, means for controlling the the outer side of each piston to produce a movement in the one or the other direction, an intermediate piston, disposed" near one of the first named pistons and movable therewith, and auxiliary means 'for admitting: fluid pressure between said intermediate piston and the nearer of the first-named pistons to cause a frictional lockin of the two pistons within the cylinder, w ereby said pistons are held in any predetermined position.
-21. A fluid-actuated means comprising a pair of p istons,a-cylinder in which the pistons operate, normally closedelectromagnetically actuated valves for controlling the sressure'in each end of the cylinder to pro- 5 ucei a movement of the member in the one :'or the other direction, an. intermediate pisexclude fluidpressure from they chamber 'ineluded between said intermediate piston and the nearer of the first-named pistons during said movement giization,-to admit fluid pressure into said chamber to cause a frictional locking of the two pistons Within the vcylinder, whereby the pistons are held'in any predetermined position. q 22. The combination with a cylinder, of a piston rod, a main piston mounted upon and adapted to actuate the said rod, and an auxiliary piston mounted uponthe said rod d adapted to lock the same in place under predetermined operating conditions.- i 23. The combination ing cylinder anda plurality of associated pistons disposed therein, .of means for admitting relatively high-pressure operating.
fluid within the chamber formed by "said cylinder and said pistons to prevent movement of said pistons.
24. The combination with a fluid-receiving cylinder and a plurality of associated pistons disposed -therein, of cupped washers associated with the pistons and projecting inwardly, the one toward the other, and means for establishing a 'ielatively high ,pressure' within the chamber formed by said and adapted, upon deiner-v a ing cylinder anda with a fluid-receiw" cylinder and said pistons to force said inner surface of-said cylinder and prevent movement of the'pistons.
washers into intimate engagement with the 25,. The combination with a fluid-receiv 'ingcylinder and a plurality of associated pistons disposed therein, of means for ad- Knitting operating fluid to said foylinder to ends and at an intermediate point of'said cylinder for governing theadmission and release of operatingfiuid.
- 27. Thercombination-with afiuid-receivplurality of associated pistons disposed therein, of a, plurality of valves severally disposedat the respective ends and at an intermediate point of said cylinder for governing the admission and only being of like construction.
In testimony whereof, I have hereunto subscribed my name this a 30th day of July, 1914.
- FERDINAND G. MOARD.
Witnesses:
CEOILE D. BILBY,
B. B. HINEs.
Copies 01' thin we may be obtained for five cents each, by addressing the"0omm1ssioner of Eatents',
' Washington, D. 0."
with a fluidq'eceiV plurality of associated release ofoperatingfinid, the end valves
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2683347A (en) * 1950-01-09 1954-07-13 Honeywell Regulator Co Hydraulic control apparatus
US2782272A (en) * 1953-05-07 1957-02-19 Richard T Cornelius Switch mechanisms
US3230838A (en) * 1963-11-14 1966-01-25 Beloit Corp Dual lock positioning cylinder
US3404650A (en) * 1965-04-14 1968-10-08 Manitowoc Shipbuilding Inc System and apparatus for translating and discharging a load
US3844378A (en) * 1971-07-26 1974-10-29 Mccabe Powers Body Co Control system for an aerial device
US4637433A (en) * 1983-10-22 1987-01-20 Kurt Stoll Solenoid valve

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2683347A (en) * 1950-01-09 1954-07-13 Honeywell Regulator Co Hydraulic control apparatus
US2782272A (en) * 1953-05-07 1957-02-19 Richard T Cornelius Switch mechanisms
US3230838A (en) * 1963-11-14 1966-01-25 Beloit Corp Dual lock positioning cylinder
US3404650A (en) * 1965-04-14 1968-10-08 Manitowoc Shipbuilding Inc System and apparatus for translating and discharging a load
US3844378A (en) * 1971-07-26 1974-10-29 Mccabe Powers Body Co Control system for an aerial device
US4637433A (en) * 1983-10-22 1987-01-20 Kurt Stoll Solenoid valve

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