US627903A - Automatic belt or motor-switch shifter. - Google Patents

Automatic belt or motor-switch shifter. Download PDF

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US627903A
US627903A US69344598A US1898693445A US627903A US 627903 A US627903 A US 627903A US 69344598 A US69344598 A US 69344598A US 1898693445 A US1898693445 A US 1898693445A US 627903 A US627903 A US 627903A
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valve
pressure
piston
belt
cylinder
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US69344598A
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Arthur Wise Cash
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FOSTER ENGINEERING Co
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FOSTER ENGINEERING 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
    • F15B13/00Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/044Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by electrically-controlled means, e.g. solenoids, torque-motors
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16HGEARING
    • F16H7/00Gearings for conveying rotary motion by endless flexible members
    • F16H7/08Means for varying tension of belts, ropes, or chains
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/305Directional control characterised by the type of valves
    • F15B2211/30525Directional control valves, e.g. 4/3-directional control valve

Definitions

  • duid-pressure tank or reservoir duid-pressure tank or reservoir.
  • This invention relates to an automatic fluidpressure-actuated belt, lever, or electricswitch shifter for starting and stopping a pump or motor and for other purposes-such, for instance, as controlling the operation of a pump for supplying fluid to a tank or reserprised in said valve, as hereinafter described,
  • Figure 1 is a longitudinal section of my improved uid-pressure-actuated mechanism for operating a belt-shifter,lever, or switch.
  • Fig. 2 is an end elevation of a stuffing-box and bracket.
  • the cylinder 1 is threaded at one end into a head or bracket 2, which is provided with On the periphery of the bracket-head there is a boss 4, through which is formed a threaded opening 5 for attachment of a pipe to connect with a This opening 5 communicates with the cylinder 1 through a port or opening 6 for yadmitting duid-pressure from the "tank or reservoirto that side of the piston-head 7 which presents the'least area or surface by reason-oftl1e piston-rod S being on that side vand ,having a comparatively large diameter.
  • the pistonhead is provided with packing-rings 9 of some soft yielding material, preferably leather,
  • the pistonrod passes out through the stuiiing-box Sand has at its end a suitably-jointed connection 55 with a connecting-rod 11,that in turn connects with the belt-shifter or the lever or switch or valve to be aetuatedby the movementsof the piston.
  • a connecting-rod 11 On the other end of the cylinder 1 there is a cap 12, that is provided with an 6o opening into ywhich is tapped a nipple or small pipe 13,;.Which Ieonnectslwith a port 14 of a three-Way automatic fiuid-pressure-eontrolled valve 15,. which communicates with the fluid-pressure tank or reservoir,.as here- 6.5
  • the casing of the valve ⁇ 15 comprises a cylindricalbody portion having at one end a circular enlargement 16, that is lscrew-threaded for engagement of a cover part 17, that tightly 7o clamps into place a flexible diaphragm 1S, which divides the valve-casing into two chambers.
  • a spring 20 In the chamber 19, on one side of this diaphragm, there is placed a spring 20, the thrust of which is exerted at one end against 75 a plate or block 2l, resting against the diaphragm.
  • the other end of the spring bears against a screw-cap 22, that can be adj usted to increase or decrease Ythe compression of vsaid spring, and thus regulate its pres- 8o sure to correspond with any standard of pressure required in lthe fluid-pressure tank or reservoir.
  • the chamber 23 on the other side 0f the diaphragm 18 communicates through aL port 24,'with an opening 25, that is provided 85V in the bodyportion of the valve-casing for attachment of a suitable pipe to connect with the fluid-pressure reservoir or tank.
  • valve-chamber 26 receives two. valves 27 and 2S, the stems of which abut'in such manner vthat when one valve is closed or seated the other Valve will be open.
  • valve-stems are tubular and roo fit the valve-chamber l26, except Where they are oircumferentially grooved on the exterior.
  • Each valve-stem is provided with radial holes 29 30, communicating with its hollow or tubu lar interior next to the valve-head, and other radial holes 31 are provided at the abutting ends of the valve-stems opposite the port 14, that communicates with the pipe 13 and connected cylinder.
  • the valve 27 is normally seated by the pressure of the spring 2Q against the diaphragm 18, and the closing of this valve 27 forces the valve 28 open against the pressure of a spring 32, that is confined in a chamber 33, formed by the enlarged portion of the bore in the body of the valve-casing.
  • the compression of the spring 32 is adjusted by means of a centrally-bored screw-plug 34, that is screwthreaded or otherwise adapted for attachment of a pipe through which the exhaust from the cylinder 1 is to escape.
  • the described mechanism is firmly secured, by means of the bracket 2, ⁇ onto the countershaft frame or other suitablesupport in such manner that the connecting-rod 11 may readily be connected to the sliding bar that carries the belt-shipper fingers, or in the case of an electrically-driven pump the bracket 2 may be bolted to the switchboard or other suitable support in suchv position as will admit of connecting the rod 11 to the switch-lever, or the differential piston may be connected in any convenient manner with a valye for controlling the operation of a pump or engine.
  • the opening' 5, which leads into the cylinder l, and the opening 25 of' the automatic valve 15 are each to be connected by suitable piping to a pressure tank or reservoir into which fluid is to be forced by a pump.
  • the threaded cap 22 will be adjusted to give sufficient compression on the spring 20 to resist orbalance seventy pounds pressure per square inch on the other side of the diaphragm 18, thus holding down said diaphragm in ⁇ such position that the valve 27 will be thereby held to its seat, and this in turn holds the valve 28 open or away from its seat.
  • the threaded cap 22 will also at all times be in that part of the cylinder l between its port 6 and the piston-head 7, and also on the under side of the diaphragm 18, through the opening 25 of the Valve-casing.
  • This outward movement of the piston actu; ates the belt-shifteror theswitch or lever or a valve (not shown) in such direction as to stop the pump.
  • the spring 22 will force the diaphragm 18 toward the valve 27,' thereby closing said valve and holding it to itsseat against the pressure of the spring 32 on the Valve 28, and. by thus seating the ⁇ valve 27 the valve 28 will be held open, so that the pressure on the larger side of -the piston 7 can fiow back through the vpipe 13 and valve-port 14, thence through the radial holes 31 into the hollow stem of the valve 28, and out through the radial holes 30 of said Valve and through the chamber 33 to the waste-passage in the plug 34 at the end ol' said chamber.
  • valves 27 and 28 are of such length in their stems or abutting parts 'that when the one is closed'against its seat the op- -posite valve is forced open or away from its seat a iiXed distance-say one sixty-fourth of an inch.
  • the spring 32 is held at an adjusted degree of compression by means of the screwplug 34, and its strength and pressure should be sufficient to hold the valve 28 firmly against TOO IIO
  • valve 27 with such power as to withstand the force of the required Huid-pressure acting against the area of the valve 28 in a direction to push it outward;
  • a proper adjustment of the springs 2O and 32 the operation of the valve 15 will be automatic and immediately sensitive -to any increase of iiuidton to be connected with a device for controlling the operation of a pump or engine to supply a pressure tank or reservoir, and a cylinder having on that side or face of said piston which is of least area a port to be con- 'nected with said pressure-reservoir, of fluidpressure-controlled valve mechanism to be connected with the pressure-reservoir and with said cylinder on that side or face of said piston which is of larger area and comprising opposed positively seating and unseating valves arranged in such manner that the closing of either valve exerts a direct pressure to open the other, substantially as described.
  • a piston inclosing cylinder having a port on that side or face of said pistonwhich is of least area,and fluid-pressure-controlled three-wayvalve mechanism adapted to communicate with said cylinder on that side or face of its piston which is of larger area and comprising opposed positively seating and unseating valves so arranged that the closingof either valve exerts a direct pressure to open the other, substantially as described.
  • a uid-pressure-controlled three-way-valve mechanism connected with said cylinder on that side or face of the piston which is of larger area and comprising two oppositelyseating valves arranged and opposing each other in such manner that the closing of one valve causes the other to open, substantially as described.
  • a fluid-pressure-actuated belt or switchl shifter the combination with a cylinder having a piston and provided' with a port on that side or face of the piston which is of least area, of fluid-pressure-controlled valve mechanism connected with said cylinder on that side or face of the piston which is of larger area and comprising two oppositely-seating valves arranged and opposing each other in such manner that the closing of one valve causes the other to open, and two springs forcing said valves together from opposite directions, substantially as described.
  • a fluid-pressure-actuated belt or switch shifter the combination with a cylinder having a piston and provided with a port on that side or face of the piston which is of least area, of iiuid-pressure-controlled valve mechanism connected with saidcylinder on that side or face of the piston which is of larger area and comprising two valve-seats, two oppositelyseating valves, two springs forcing said valves together from opposite directions and so adjusted that the closing of one valve will cause the other to open, a fiexible diaphragm between one of said valves andits spring, means for adjusting thecompression of said spring against the diaphragm, and a casing for the diaphragm and valves provided with suitable ports, substantially as described.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Fluid-Driven Valves (AREA)

Description

No. 627,Q03.- Patented lune 27. |899. A. W. CASH.
AUTOMATIC BELT UR MDTOR SWITCH SHIFTER.
(Application med oci. 13, 189e.)
(No Model.)
. ywr? .ma 5 d .mmf www A u uw ...WFA w W Nl . a stuffing-box 3 on its outer side.
duid-pressure tank or reservoir.
4UNITEI)` STATES PATENT OFFICE.-v
ARTHUR WISE c'AsI-I, oF NEWARK, NEW JERSEY, AssIGNoR rro THE FOSTER ENGINEERING coMPANRJoF SAME PLACE.
AUTOMATIC BELT MOTOR-SWITCH SHI'FTER.
SPECIFICATION forming part of Letters Patent N'o. 627,903, dated J' une 27, 1899. Application filed Gi70b1` 13, 1898- Serial No. 6931445; (No model.)
T0 @ZZ whom t may concern;
Be it known that I, ARTHUR WISE CASH, a
citizen of the United States, resding'at New-v ark, in the county of Essex and State of New Jersey, have invented'new and useful I-rnprovements in Automatic. Belt or Motor- Switch Shifters, of which the following is a specification.
This invention relates to an automatic fluidpressure-actuated belt, lever, or electricswitch shifter for starting and stopping a pump or motor and for other purposes-such, for instance, as controlling the operation of a pump for supplying fluid to a tank or reserprised in said valve, as hereinafter described,
and claimed.
In the annexed drawings, illustrating the'v invention, Figure 1 is a longitudinal section of my improved uid-pressure-actuated mechanism for operating a belt-shifter,lever, or switch. Fig. 2 is an end elevation of a stuffing-box and bracket.
The cylinder 1 is threaded at one end into a head or bracket 2, which is provided with On the periphery of the bracket-head there is a boss 4, through which is formed a threaded opening 5 for attachment of a pipe to connect with a This opening 5 communicates with the cylinder 1 through a port or opening 6 for yadmitting duid-pressure from the "tank or reservoirto that side of the piston-head 7 which presents the'least area or surface by reason-oftl1e piston-rod S being on that side vand ,having a comparatively large diameter. The pistonhead is provided with packing-rings 9 of some soft yielding material, preferably leather,
and may be secured tothe piston-rod by means of a nut 10 or otherwise. The pistonrod passes out through the stuiiing-box Sand has at its end a suitably-jointed connection 55 with a connecting-rod 11,that in turn connects with the belt-shifter or the lever or switch or valve to be aetuatedby the movementsof the piston. On the other end of the cylinder 1 there isa cap 12, that is provided with an 6o opening into ywhich is tapped a nipple or small pipe 13,;.Which Ieonnectslwith a port 14 of a three-Way automatic fiuid-pressure-eontrolled valve 15,. which communicates with the fluid-pressure tank or reservoir,.as here- 6.5
inafter explained.
The casing of the valve `15 comprises a cylindricalbody portion having at one end a circular enlargement 16, that is lscrew-threaded for engagement of a cover part 17, that tightly 7o clamps into place a flexible diaphragm 1S, which divides the valve-casing into two chambers. In the chamber 19, on one side of this diaphragm, there is placed a spring 20, the thrust of which is exerted at one end against 75 a plate or block 2l, resting against the diaphragm. The other end of the spring bears against a screw-cap 22, that can be adj usted to increase or decrease Ythe compression of vsaid spring, and thus regulate its pres- 8o sure to correspond with any standard of pressure required in lthe fluid-pressure tank or reservoir. The chamber 23 on the other side 0f the diaphragm 18 communicates through aL port 24,'with an opening 25, that is provided 85V in the bodyportion of the valve-casing for attachment of a suitable pipe to connect with the fluid-pressure reservoir or tank.
In the body portion of the valvecasing there is a central longitudinal bore that is of 9o reduced diameter for part of its length, next to the diaphragm-chamber 23, and of enlarged diameter at the outer end of said valvecasing. The reduced portion of said bore forms ya valve-chamber 26, having a valve- 954 seat at each end. This valve-chamber 26 receives two. valves 27 and 2S, the stems of which abut'in such manner vthat when one valve is closed or seated the other Valve will be open. jThe valve-stems are tubular and roo fit the valve-chamber l26, except Where they are oircumferentially grooved on the exterior.
.v i v Each valve-stem is provided with radial holes 29 30, communicating with its hollow or tubu lar interior next to the valve-head, and other radial holes 31 are provided at the abutting ends of the valve-stems opposite the port 14, that communicates with the pipe 13 and connected cylinder.
The valve 27 is normally seated by the pressure of the spring 2Q against the diaphragm 18, and the closing of this valve 27 forces the valve 28 open against the pressure of a spring 32, that is confined in a chamber 33, formed by the enlarged portion of the bore in the body of the valve-casing. The compression of the spring 32 is adjusted by means of a centrally-bored screw-plug 34, that is screwthreaded or otherwise adapted for attachment of a pipe through which the exhaust from the cylinder 1 is to escape.`
For use in operating a belt-shifter the described mechanism is firmly secured, by means of the bracket 2, `onto the countershaft frame or other suitablesupport in such manner that the connecting-rod 11 may readily be connected to the sliding bar that carries the belt-shipper fingers, or in the case of an electrically-driven pump the bracket 2 may be bolted to the switchboard or other suitable support in suchv position as will admit of connecting the rod 11 to the switch-lever, or the differential piston may be connected in any convenient manner with a valye for controlling the operation of a pump or engine. The opening' 5, which leads into the cylinder l, and the opening 25 of' the automatic valve 15 are each to be connected by suitable piping to a pressure tank or reservoir into which fluid is to be forced by a pump. If itis desired to carry, say, seventy pounds pressure in the tank, the threaded cap 22 will be adjusted to give sufficient compression on the spring 20 to resist orbalance seventy pounds pressure per square inch on the other side of the diaphragm 18, thus holding down said diaphragm in` such position that the valve 27 will be thereby held to its seat, and this in turn holds the valve 28 open or away from its seat. Of course whatever uidfpressu re there may be in the tank or reservoir will also at all times be in that part of the cylinder l between its port 6 and the piston-head 7, and also on the under side of the diaphragm 18, through the opening 25 of the Valve-casing. When the pressure in the tank is n o more than su flicientto balance the compression of the 'spring 2O as adjusted by the cap 22, the piston 7 will occupy, as shown, such position as will cause the belt-shifter or theswitch to permit operation of the pump for v :maintaining the required fluid-pressure in the tank. Now as soon as the pressurein the tank reaches a point above seventy pounds it will force'the diaphragm 18`back against the'pressure of the spring 20, thus permitting the valve 27 to open under the pressure exerted by the spring 32 in closing or forcing the valve 28 toits seat. Thus-the valve 27 will be held open, while the valve 28 will be held closed. The fluid-pressure now'enters the small radial holes 29 of the valve 27, passes through the tubular or hollow valve-stem, out through the radial holes 31, and thence through the valveport 14 and pipe 13 into the cylinder 1 toact against the full area of the adjacent side ot' the piston head 7, thereby overcoming the same pressure acting against the reduced area of the opposite face of the piston-head and so forcingthe piston outward and holding it in that position until the Huid-pressure' in the tank again falls to seventy pounds or below. This outward movement of the piston actu; ates the belt-shifteror theswitch or lever or a valve (not shown) in such direction as to stop the pump. Then the Huid-pressure in the tank falls to seventy pounds or less, the spring 22 will force the diaphragm 18 toward the valve 27,' thereby closing said valve and holding it to itsseat against the pressure of the spring 32 on the Valve 28, and. by thus seating the `valve 27 the valve 28 will be held open, so that the pressure on the larger side of -the piston 7 can fiow back through the vpipe 13 and valve-port 14, thence through the radial holes 31 into the hollow stem of the valve 28, and out through the radial holes 30 of said Valve and through the chamber 33 to the waste-passage in the plug 34 at the end ol' said chamber. In the meantime the pressure in the cylinder 1 between the port 6 andpiston-head 7 will force the piston back to its former position, as shown, and through this movement of the piston the belt-shifter will be actuated in such direction as to carry the driving-belt of the pump back onto the tight pulley for starting the pump or in like manner will actuate a valve or a switch or lever for a similar purpose. The same principle applies whether the motor is operating a hydraulic pump or an air pump or compressor and whether the starting and stopping are to be effected through a belt-shifter or a lever or an electric switch.
As shown, the valves 27 and 28 are of such length in their stems or abutting parts 'that when the one is closed'against its seat the op- -posite valve is forced open or away from its seat a iiXed distance-say one sixty-fourth of an inch. The spring 32 is held at an adjusted degree of compression by means of the screwplug 34, and its strength and pressure should be sufficient to hold the valve 28 firmly against TOO IIO
the valve 27 with such power as to withstand the force of the required Huid-pressure acting against the area of the valve 28 in a direction to push it outward; Thus by a proper adjustment of the springs 2O and 32 the operation of the valve 15 will be automatic and immediately sensitive -to any increase of iiuidton to be connected with a device for controlling the operation of a pump or engine to supply a pressure tank or reservoir, and a cylinder having on that side or face of said piston which is of least area a port to be con- 'nected with said pressure-reservoir, of fluidpressure-controlled valve mechanism to be connected with the pressure-reservoir and with said cylinder on that side or face of said piston which is of larger area and comprising opposed positively seating and unseating valves arranged in such manner that the closing of either valve exerts a direct pressure to open the other, substantially as described.
2. In a iluicl-pressure-actuated belt, lever or switch shifter, the combination of a piston, an inclosing cylinder having a port on that side or face of said pistonwhich is of least area,and fluid-pressure-controlled three-wayvalve mechanism adapted to communicate with said cylinder on that side or face of its piston which is of larger area and comprising opposed positively seating and unseating valves so arranged that the closingof either valve exerts a direct pressure to open the other, substantially as described.
3. In a luid-pressure-actuated belt or switch shifter, the combination with a cylinder having a piston and provided with a port on that side or face of the piston which is of least area, of a uid-pressure-controlled three-way-valve mechanism connected with said cylinder on that side or face of the piston which is of larger area and comprising two oppositelyseating valves arranged and opposing each other in such manner that the closing of one valve causes the other to open, substantially as described.
4. In a fluid-pressure-actuated belt or switchl shifter, the combination with a cylinder having a piston and provided' with a port on that side or face of the piston which is of least area, of fluid-pressure-controlled valve mechanism connected with said cylinder on that side or face of the piston which is of larger area and comprising two oppositely-seating valves arranged and opposing each other in such manner that the closing of one valve causes the other to open, and two springs forcing said valves together from opposite directions, substantially as described.
5. In a fluid-pressure-actuated belt or switch shifter, the combination with a cylinder having a piston and provided with a port on that side or face of the piston which is of least area, of iiuid-pressure-controlled valve mechanism connected with saidcylinder on that side or face of the piston which is of larger area and comprising two valve-seats, two oppositelyseating valves, two springs forcing said valves together from opposite directions and so adjusted that the closing of one valve will cause the other to open, a fiexible diaphragm between one of said valves andits spring, means for adjusting thecompression of said spring against the diaphragm, and a casing for the diaphragm and valves provided with suitable ports, substantially as described.
In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.
ARTHUR WISE CASI-I.
US69344598A 1898-10-13 1898-10-13 Automatic belt or motor-switch shifter. Expired - Lifetime US627903A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2467434A (en) * 1947-05-10 1949-04-19 Air Associates Inc Servomotor and pressure responsive valve therefor
US4100936A (en) * 1975-05-30 1978-07-18 Irrifrance Three-way hydraulic valve

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2467434A (en) * 1947-05-10 1949-04-19 Air Associates Inc Servomotor and pressure responsive valve therefor
US4100936A (en) * 1975-05-30 1978-07-18 Irrifrance Three-way hydraulic valve

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