US2735404A

US2735404A - L- komph

Info

Publication number: US2735404A
Authority: US
Publication date: 1956-02-21
Anticipated expiration: 1973-02-21

Description

1955 w. KOMPH, SR

RECIPROCATING FLUID ACTUATEJD MOTORS AND CUSHIONING VALVE THEREFOR Filed Dec. 51, 1952 R w m w m MM W n L TI u U M l I JP I: N 1|: I\H[\ L I m Y F h W B b MY \N Q v Q1. k l I Q Rh I w wv k m h M h u RN Ill \h a k NM \k. Q \h b R R NM cw Q W1 United States Patent 6 RECIPROCATING FLUID ACTUATED MOTORS AND CUSHIONING VALVE THEREFOR William L. Komph, Sn, Port Huron, Mich, assignor to The Wellman Engineering Company, Cleveland, Ohio, a corporation of Ohio Application December 31, 1952, Serial No. 329,066 9 Claims. (Cl. 12138) The present invention relates to fluid pressure actuated reciprocating-type motors and, more particularly, to means for cushioning or slowing down the speed of movement of the movable member of the motor as one or both ends of the stroke is approached.

It is customary to provide reciprocating-type, fluid pressure actuated motors with means for cushioning or slowing down the speed of movement as one or both ends of the stroke are aproached and thus reduce the shock of stopping at the end or ends of the stroke especially, in applications where such motors are employed to move heavy masses under conditions where considerable momentum is built up and damage to the device may result if the movement is not cushioned at the end of the stroke.

The amount of cushioning needed depends on the speed of movement, the amount of mass being moved, etc., and one of the objects of the invention is the provision of a novel and improved fluid pressure motor of the character referred to, so arranged and designed that it will be simple and rugged in construction, positive and reliable in operation, and inexpensive to manufacture, the cushioning means of which is such that cushioning strokes of different lengths can be conveniently obtained to suit different operating requirements.

Another object of the invention is the provision of a novel and improved, fluid pressure motor of the character referred to having the cushioning means constructed, for the most part, separate and apart from the cylinder proper, thus facilitating maintenance, etc.

Another object of the invention is the provision of a novel and improved fluid pressure motor of the character referred to which will allow full flow of operating fluid to the cylinder immediately upon reversal of the motor, thus eliminating the lag prevalent in prior cushioning arrangements.

Another object of the invention is the provision of a novel and improved fluid pressure motor of the character referred to comprising cushioning means which is especially adapted to conditions where relatively long cushioning strokes are desired.

A further object of the invention is the provision of a novel and improved cushioning valve designed and constructed as a separate unit, capable of being operatively readily attached to and removed from the motor proper.

The invention resides in certain constructions and combinations and arrangements of parts and further objects and advantages will be apparent to those skilled in the art to which it relates from the following description of the preferred embodiment described with reference to the accompanying drawing which shows a double-acting, fluid pressure operated motor and control therefor embodying the present invention.

Referring to the drawing, the reference character A designates generally a double-acting, reciprocating-type, fluid pressure actuated motor. The fluid pressure motor A comprises a cylinder assembly B including a hollow cylinder proper, designated 10, closed at opposite ends by detachable heads 11, 12 to form a cylinder bore 13 and a piston assembly C comprising a piston 14 located in the cylinder bore 13 and connected to a piston rod 15, which rod extends to the exterior of the cylinder bore 13 through a suitable aperture 16 in the head 11. The aperture 16 in the head 11 through which the piston rod 15 extends is provided with a conventional packing gland, designated generally by the reference character 17, to prevent the escape of fluid around the piston rod. The piston 14 is provided with conventional sealing rings 18.

As previously stated, the motor A is of the doubleacting type and fluid is admitted to and exhausted from opposite ends of the cylinder bore 13 by conduits or passages 20, 21 formed in the cylinder heads 11, 12, respectively. The ends of the conduits opening into the exterior of the cylinder heads are tapped or otherwise formed to facilitate connecting pipes or tubes thereto, as the case may be.

The flow of fluid to and from opposite ends of the cylinder bore 13, in the embodiment shown, is under the control of a conventional, four-Way valve D which may be either manually or automatically controlled, as desired. Any other suitable, means, however, may beemployed for this purpose. The valve D is of commercial construction and will not be described in detail. Suffice it to say that it consists of a valve proper, designated generally by the reference character 22, slidably supported in a bore'23 in a valve housing 24. The valve housing has suitable ports or conduits therein which are so arranged that upon reciprocation of the valve 22 to opposite ends of the cylinder 24, the

ports

25, 26 are alternately connected with fluid pressure and exhaust ports or conduits 27, 28. When the valve 22 is set in an intermediate position, the

passages

25, 26 are closed by suitable lands forming a part of the valve 22.

According to the provisions of the present invention, the means for controlling the flow of fluid to and from the motor, in the present instance, the control valve D is connected to opposite ends of the power cylinder through the medium of conduit means including a novel and improved valve for cushioning or slowing down the speed of movement of the motor at the end of the stroke. This mechanism, as shown, comprises valves E and F interposed or connected in the conduit means connecting the control valve D with opposite ends of the power cylinder. Both of the valves E and F are identical in construction; they are, however, connected to opposite ends of the power cylinder. Only the valve E connected to the right-hand end of the power cylinder, as viewed in the drawings, will be described in detail and the corresponding parts of the valve F will be designated by the same reference characters with a prime mark aflixed thereto.

The valve E, as shown, comprises a cylinder housing 30 having a cylinder bore or aperture 31 therein opening into the left-hand end of the housing where it is closed by a cylinder head 32 detachably connected to the housing 30 by screws, not shown. A piston 33, approximately one-half of the length of the valve cylinder, is slidably supported therein and adapted when adjacent to one end, that is, the right-hand end as viewed in the drawing, to close communication between relatively large conduits or passages 34, 35 of substantially the same cross-sectional area in the housing 30 opening into the right-hand end of the valve cylinder and the valve cylinder wall adjacent to but spaced from the right-hand end, respectively. When the piston 33 is in the opposite end of the valve cylinder, that is, in the left-hand end, the conduits or ports 34, 35 are in communication with each other through the right-hand end of the valve cylinder.

Leakage of fluid around or past the piston 33 is prevented by suitable seals 36; 37, the former of which is located ina suitable annular groove, in the.PistQn.3,3, ad: jacent to but spaced from its left-hand end and the latter in a suitable annular groove in the housing 30 opening into the; cylinder boreltl and located intermediate the.

right-hand end, of: the valve cylinder and the place wherethe;,conduit35 opens into .the side of the cylinder'bore.

The cylinder housing 39 is also provided'with: relatiyely. small: conduits or passages'40, 41 intersecting each other. at; right angles and opening into. the passages-34, 35,-;respectively; The right-hand end of the passage 41 is=.counterboredtonenlarged to receive, a needle valve 42 and; a:.suitable. packing. gland, designated: generally 43. The: needle valve 42zisthreaded into, the packing gland for adjusting purposes and is adapted to be locked in any: adjusted position by. a lock: nut 44. The inner or leftehand endz 45 of the needle valve 42 is-formed generallydike-acone and cooperates with a shoulder formed by. the reduced inner end of the passage 41 to produce an adjustableorificefor restrictingand varying the flow of fluidsthroughthe-conduit 41 The reference character 46 designates: a plug for closing theouter endof the passage 40.

'Ilhea valves E: and" F, as shown, arecarriedbythe cylinder.- assembly-.A- and are connected to opposite ends thereofi byv nipples 50.,- 5'1- threaded into the ports or passages 35 and121, 35', respectively. The control valve D isconnected tothe respective valves- E and F bytconduibmeans, designated 52, 53, respectively, communicating-with the

passages

25, 26 in the control'valve DJ andzwith the passages. 34, 34' in the valves E and F, respectively.

The ends of the cylinder bores 31, 31' opposite to the ends with. which thepassages- 34, 35 and 34, 35 com municateware connectedto the power cylinder at a suit-- able, distance; from; the respective ends to which the valyesjE and F are connected thereto by

conduits

54, 55,-;formedi Oftubingconnected by. suitable fittings to ports .or;

passages

56, 56 in the cylinder heads 32, 32' and portsgorapertures 57, 58 in the cylinder member 10. The; distancethat the apertures 57, 58 are from the respective adjacentends of-the power cylinder will depend upon: the, length of cushioning stroke desired which, as previously; stated, is a' function of the. speed of movement, the-amount of mass being moved, etc, and can be readily; changed for dilferent operating conditions.

The;op.e ration isyas'follows: Assuming thatthe power piston assemblyC has just reached the end of its lefthandstroke, the various parts will be in the'respective pesitions shown inthedrawing. The valve-piston 33 of the; valyeEwillbe inv the left-hand end of the right-hand valve; cylinder; and the piston 33' of the valve P will he inlthe; left-hand end of; the other-valve cylinderbutwith respect-otthe, various; passages andports-of the valves:

and? thevalvezpistons will be; in opposite ends of the valyercylinders since, the valves, as shown, arezre versed; Upon movement otthe. valve-22 to the opposite end of its cylinder 33, the control valve will be actuated toreye-rsethedirectionof flow of fluid in the conduits 52,v 53;-ar1d{ pressure fluid will be admitted to the valve F-through the conduit 53. As, soon as pressure fluid is applied .torthe valve F through the conduit-53 the-valve piston33f isinstantaneouslyshifted, to the opposite or right-hand'endofits; valve cylinder, uncoveringthe port- 35f; and, allowingunobstructed flow of pressure fluid from the tube 53-through the port 34, the left-hand end of the; cylinder bore, 31, the port 35', the nipple Sland the port21 totheleft-handend of thecylinder assembly Btof the motor Aefiectinginstantaneous reversal of the fluid pressure motor A. The factthat the port or open-- inglof thepassage34'v in the cylinder F enters into the end; of: the valve cylinder is an advantage as the flowv of fluid under. pressure upon the head of thevalve piston 33i will assistthepressurein shifting the valve piston to the right-hand end of-the valve cylinder.

The presence of pressure fluid in the left-hand end of he. power. cylinderv will. force. the piston. assembly C to ward the right moving the load connected thereto at a speed dependent upon the amount of pressure fluid entering the motor through the passage 21. As the piston assembly moves toward the right, fluid from the righthand end of the motor A will be exhausted without appreciable back pressure through the aperture or portZO, the nipple 50',- the passage or port 35, the right-hand end of the valve cylinder 31 and the conduits 34, 52. Movement of the piston assembly C toward the right will'cause the piston to move-past the port or opening 58- in the power cylinder, thus admitting pressure fluid to the conduit 55and, in:turn,- the right-hand end of they lefthand valve cylinder. This, however, will have no effect upon the cushioning valve F'as the pressures on opposite ends of the valve piston 33' will balance each other.

When the piston 13 has proceeded to the right far enough to expose the aperture 57 in the power cylinder tothe fluid: pressure to the left of the piston head 13; fluid pressurewill be conducted throughthe conduit 5'4 tow the: left=hand;end. of the right-hand valve cylinder31' of the cushioning valve; E. This will cause the piston 33fofthe: cushioning valve E to move to the right-hand end of:the valve cylinder 31; thus closing communication between the-;conduits 34, 35 through the left-hand end ot' thevalve: cylinder. Back pressure will be immediately built-up in the motor A on the right-hand side of the piston-l3; thus:cushioning and slowing down the speed of movementof thepiston assembly C and its connected load. The; fact that the passage or conduit 35 enters into:the side of: the valve cylinder bore 31, the back pressure created by the closing of the passage does not tend' to; exert a force upon the valve piston 33, tending to shiftitytoits retracted or left-hand position. This-isimportant; particularly in instances where the back presmotor-1A. is;forced' to escape through the conduits 40,

41 of relatively small diameter. The rate of this escapeand,'=. in-turn, the" amount of cushioning efiect produced cambecontrolled by'varying the size of the orifice therein:by.adjusting the needle valve 42. When the motor A has. reached the end of its stroke, the control valve D is reversed and the operation is repeated.

Whilein the; preferred embodiment of the invention shown the valve which controls the cushioning stroke is incorporated'in a unit separate and apart from the cylinderassembly: and connected thereto by tubing or the like, it isto be understood that the valving may be in-- corporated in and form an integral part of thecylinder assembly: Asshown, the valve pistons are fluid pressure. actuated in: both directionsand while-this is the preferred construction, it is to-be understood that the pistons may be spring-retracted to permit full flow of fluid to and from the power cylinder and pressure advanced in a manner similar to' that shown to close the exhaustpassage through the valve cylinder when back pressure is desired. In;,this, event. the passages 34, 34' instead of being in the endsofutheuvalvev cylinders, as shown, could beuin. the sidewallsthereof, as arethe passages 35, 35'. Thefact, that the:valving which controls the cushioning stroke.is,.. in. the'preferred embodiment shown, constructed as a separateunit, permitsthe valving to be placed at anydesired; locationwith, respect. to the cylinder assembly, thus. facilitating rnaintainance particularly in places: where the cylinder is relatively inaccessible.

From the=foregoing description of the preferredembodiment of the invention, it will be apparent that the. objects heretoforeenumerated and others have been acacomplished and'that-therehas been provided a novel and improved fluid pre'ss'u're motor of the reciprocating type having cushioning means which will permit full flow of the operating fluid to the cylinder immediately upon reversal of the motor, permit cushioning strokes of different length to be conveniently obtained to suit varying operating requirements, which is especially adapted to cushioning strokes of considerable length and, if desired, can be located to a large extent outside of the cylinder proper, thus facilitating maintainance in the event the cylinder is in an inaccessible place.

While the preferred embodiment of the invention has been described with considerable detail, the invention is not limited to the particular construction shown and it is my intention to cover hereby all adaptations, modifications and uses thereof which come within the practice of those skilled in the art to which the invention relates and within the scope of the appended claims.

Having thus described my invention, I claim:

1. In a reciprocatingtype fluid pressure actuated mechanism, a power cylinder, a valve cylinder, a first port or aperture in one end of said valve cylinder adapted to be selectively connected with a source of fluid pressure and with exhaust, a second port or conduit in one side of said valve cylinder adjacent to but spaced from said one end of said valve cylinder and in communication with one end of said power cylinder, a piston-like valve member reciprocable in said valve cylinder to open and close said second port or conduit, a third port or conduit in the other end of said valve communicating with said power cylinder intermediate opposite ends thereof, a fourth conduit connecting said first and second conduits, and a variable orifice in said fourth conduit.

2. In a reciprocating type fluid pressure actuated mechanism, a power cylinder, a valve cylinder, a first port or aperture in one end of said valve cylinder adapted to be selectively connected with a source of fluid pressure and with exhaust, a second port or conduit in one side of said valve cylinder adjacent to but spaced from said one end of said valve cylinder and in communication with one end of said power cylinder, an annular groove in said valve cylinder wall intermediate said second conduit and said one end of said valve cylinder, an annular seal in said groove, a piston-like valve member reciprocable in said valve cylinder to open and close said second port or conduit, a third port or conduit in the other end of said valve communicating with said power cylinder intermediate opposite ends thereof, a conduit connecting said first and second conduits, and means for varying the passage through said fourth conduit.

3. In a valve for a reciprocating type fluid pressure actuated mechanism having a power cylinder, a valve cylinder, a first port or aperture in one end of said valve cylinder adapted to be selectively connected with a source of fluid pressure and with exhaust, a second port or conduit in one side of said valve cylinder adjacent to but spaced from said one end of said valve cylinder and adapted to be connected with one end of the power cylinder, a piston-like valve member reciprocable in said valve cylinder to open and close said second port or conduit, a third port or conduit in the other end of said valve adapted to be connected with the power cylinder intermediate opposite ends thereof, a conduit connecting said first and second conduits, and means for varying the size of the passage through said fourth conduit.

4. In a reciprocating type fluid pressure actuated mechanism, a power cylinder, a valve chamber, a first port or conduit at one end of said valve chamber adapted to be selectively connected with a source of fluid pressure and with exhaust, a second port or conduit in one side of said valve chamber in communication with one end of said power cylinder, a valve member reciprocable in said valve chamber adapted to open communication between said first and second ports when in one position and to close communication between said first and second ports when in its alternate position and having a portion thereof adapted to overlie saidsecond port when in its closed that fluid can pass through said fourth conduit ,when' said valve member closes communication between said first and second ports.

5. In a reciprocating type fluid pressure actuated mechanism, a power cylinder, a valve cylinder, a first port or conduit at one end'of said valve cylindenadapted to be selectively connected with a source of fluid pressure and with exhaust, a second port or conduit in one side of said valve cylinder in communication withone end of said power cylinder, a third port or conduit at the other end of said valve cylinder, communicating with said power cylinder intermediate opposite ends thereof, a piston-like valve member reciprocable in said valve cylinder adapted to opencommunication between said first and second ports when in one position and to close communication between said first and second ports when in its alternate position and having a portion thereof adapted to overlie said second port when in its closed position, sealing means between said piston-like valve member and the walls of said cylinder on either side of said second port when said valve is in its closed position, and a fourth conduit connecting said first and second conduits such that fluid can pass through said fourth conduit when said valve member closes communication between said first and second ports.

6. In a valve, a valve chamber, a first port or conduit at one end of said valve chamber adapted to be selectively connected with a source of fluid pressure and with exhaust, a second port or conduit in one side of said valve chamber adapted for flow into and flow out of said valve chamber, a valve member reciprocable in said valve chamber adapted to open communication between said first and second ports when in one position and to close communication between said first and second ports when in its alternate position and having a portion thereof adapted to overlie said second port when in its closed position, a third port or conduit at the other end of said valve chamber for the period application of fluid pressure to said valve chamber sufficient to move said valve member, and a fourth conduit connecting said first and second conduits such that fluid can pass through said fourth conduit when said valve member closes communication between said first and second ports.

7. In a valve, a valve chamber, a first port or conduit at one end of said valve chamber adapted to be selectively connected with a source of fluid pressure and with exhaust, a second port or conduit in one side of said valve chamber adapted for flow into and flow out of said valve chamber, a valve member reciprocable in said valve chamber adapted to open communication between said first and second ports when in one position and to close communication between said first and second ports when in its alternate position and having a portion thereof adapted to overlie said second port when in its closed position, a third port or conduit at the other end of said valve chamber for the periodic application of fluid pressure to said valve chamber suflicient to move said valve member, sealing means between said valve member and said chamber on either side of said second port when said valve is in its closed position, and a fourth conduit connecting said first and second conduits such that fluid can pass through said fourth conduit when said valve member closes communication between said first and second ports.

8. In a valve, a valve cylinder of substantially uniform cross section throughout its operable length, a first port or conduit at one end of said valve cylinder adapted to be selectively connected with a source of fluid pressure and with exhaust, a second port or conduit in one side of said valve cylinder adapted for flow into and flow memos;

agp licationoft fluid pressure to saidvalve: cylinder to move said valvesmembcr: from the openttotthe. closed, position, and: a fourthconduit v connecting said t first and. second. conduits-such that fluid cannassthroughsaidfourthiconduit: when saidtvalve overlies saidtsecondiport.

9.. In: a valve, a valve ,cylinder of substantially uniform cross section throughout its: operablet lengthh aq firsltgorl or, conduit at, one end ofzsaidvalve cvlindcr adagtecl to betselectivelv connected withas source of fluid pressure and-.withjexhaust; a second pprtor; conduit in; one side of :said; valve cylinder: adapted for flow, into and silowv out of, said valve cylinder, at piston-likewalvemember; re? cinrocable in said, valve cylinder adapted to open, com:

mnnication betweenisaidfirst, and. second ports when; in- Ones. position and: to close communication between said first and, :second pprts when in its alternate gosition saidgt valvemflmben being adaptedto overlie saidisecondjgoitts when ill-its: closed: position, a. third om or conduit atz: theothen end of. said valve cylinden for theperiodic ape- I plication of fluid gressureto said valvetcylinderttosmover said valve: fromthe open to the closedsp osition, sealing:

means betweensaid, piston-like valvev member. and; the walls of said cylinderv oneither side;of said secondportwhensaid, valve is in its: closed position, and a fourth;

conduit connecting said firstrand second conduits such that fluid can pass through said fourth conduit when said valve overliesisaid secondport.

References Cited-in the file'bf this'patent UNITED. STATES PATENTSv 603558 Bailout.-- iMay*3;, 1.898;. 1,023,267 Mocktetaln s Apr., 1.6;.19-12; 1,283,179 Hennebohlef Oct: 29,1918 2,223,792 Muir" a Dec. .3 ,1 19.40 2,431,210 Tammi Nov.- 13, 1947 FOREIGN PATENTS 157,890. Great Britainmu Aug. l1, 1921