US2445985A - Combined fluid-operated motor and pump - Google Patents

Description

y 7, .1948. H. J. WERNER. 2,445,985

COMBINED FLUID-OPERATED MOTOR AND PUMP Filed- Jan. 28, 1,946

' make provision for peak loads.

Patented July 27, 1 48 Q Herbert 1. Werner, Chicago, Ill., assignor of onehalttoFi-ank P. Werner, OhlcagoJll.

Application January as, 1946, Serial No. 043.1194 I 8 Claims. (]."103-51) The conventional practice for creating high hydraulic pressure to operate machines and apparatus of various kinds as, for example, a press or a vise, is to employ a radial pump driven by an electric motor. The motor must be of sulficient horsepower to take care of. peak loads, although the maximum demand may last for only a small part of the working cycle. Furthermore, the pressure obtainable with radial pumps is limited by the fact that the oil film that lubricates the closely fitted component parts of the pump breaks down when a predetermined pressure is reached; the maximum pressure attainable being, in practice, necessarily one that is safely below such predetermined pressure.

he, and operates at low efliciency, but in many cases, the pressure at which liquid can be pumped sitating substantial increase in cost in order to In carrying out my invention, I employ two reciprocating pumps and a novel reciprocatory air driven engine or motor; so that, viewed in one of its aspects, the present invention may be said to have for its object to produce at a reasonably low cost. a simple, unique, eflicient and durable engine of the air driven hydraulic type.

Another object of my invention is to provide a novel and eilicient combined motor and pump: the motor driving the pump being actuated or power-driven by a fluid, such as air, water or other fluid under pressure and the pump being capable of furnishing fluid, such as oil, under high pressure for operating hydraulic presses,hy-. draulic Vises or other fluid-actuated apparatus devices or motors,

The various features of novelty whereby the present invention is characterized will hereinafter be pointed out with particularity in the appended claims; but, fora full understanding of the invention and of its objects and advantages, reference may be had to the following detailed description taken in connection with the accompanying drawing. wherein:

Consequently, the motor is not only more costly than it should 2 J Fig. 1 is an end view of a combined motor and pump unit embodyingthe present invention;

Fig. 2 is a top plan view of said unit;

Fig. 3 is a horizontal section taken on line 3-3 of Fig. 1; and

Fig. 4 is a vertical section taken on line 4-4 of Fig.2.

Referring to the drawing, "represents a cylinder block-composed of three sections, Ii, l2 and I3, arranged end to end and secured together. The central section l2, which maybe termed the motor section is preferably a thick walled cylindrical shell, has on the bottom side thereof a pair of oppositely disposed laterally aligned feet ii that form a sturdy base adapted to rest against or upon and be secured to a ilat surface on a wall, floor, foundation or other suitable support. At the axis of the block II are three aligned cylindrical chambers Ii, I1 and i8, one in each block section and opening one into another. The end chambers I6 and I8. which are the p mp cylinders, are of relatively smaller diameter than the motor chamber ill and terminate short of the outer ends of the respective block sections in which they are located. The middle chamber, which is the motor or power cylinder, is of much larger diameter than the pump cylinders. The motor block section I! is preferably provided at each end with a cylindrical flat-faced recess l9 somewhat larger indiameter than the motor cylinder ll. Each end section of the block has at its inner end an annular flange 20 that fits and seats into the ad- Jacent cavity or cylindrical recess is in the central block section It. Each of these flanges 26 defines a cylindrical'valve-chamber 2| somewhat larger in diameter than and coaxial with the motor cylinder II. In each of the valve chambers 2| is a flat disc valve'22, the thickness of which is convenientlyabout one half of the depth of the valve chamber 2| in which it is slidably mounted. Each disc valve 22 contains transverse openings 24 disposed preferably opposite These openings 24 function as air passages as will later be more fully explained. Behind each disc valve 22 are a plurality of compression springs 25 which tend constantly to hold it against the adjacent end face of the central block section I 2.

Slida-bly mounted within the three cylinders are three pistons connected together into a single 'coacting rigid structure. This structure of interconnected pistons may be a unitary structure .made from one piece of metal and may be said to consist of a shaft 26 having thereon pistons 21, 23 and 23 slidably mounted for reciprocation in cylinders l6, l1 and I3, respectively. The shaft 26 extends slidably through the disc valves 22. The motor power piston 23 has thereon hubs 36 of smaller radius than the radial distance from the axis of the shaft 26 to the nearest points of the openings 24 in the disc valves 22 whereby these hubs 33 may strike the valves 22 and force them back against the flat end faces of their chambers without covering the openings 24 in the disc valves 22.

The motor is preferably operable by air under pressure but any other suitable fluid, such as for example water or oil may be used. Them otivating fluid under pressure is delivered to the power cylinder l1 through a supply pipe 3|, which is preferably provided with a control valve 32 adapted to be operated in any suitable way, man"- ually or otherwise. As best shown-in Fig.4, this fluid power inlet pipe' 3| opens into the stem portion of a T-shaped port 34 in the central block section l2; the ends of the cross arm of the T-shaped port 34 registering with intake ports 35 in the annular flanges on the inner ends of the block sections H and I3. These ports 35 are so located that when the disc valves 22 are alternately pressed back by the hubs 33 of the motor piston 23 against the pressure of the springs 25 air or other fluid under pressure may enter the power cylinder l1 through such ports 35. On the other hand, when the disc valves 22 are at the other limit of their movement, the ports are covered by the circular faces of the corre-' sponding valves and thus prevent the motivating fluid from entering the power cylinder l1. Exhaust ports 36 in the annular flanges 23 connect the valve chambers 2|. with outlet ports 31 4 a of when it reaches the power cylinder, may be regulated'fby valve 32. The power-transmitting or work-producing fluid to be pumped may be withdrawn from 'a suitable supply tank, not

extending through the lower portion of the cen- V tral block section l2; these exhaust ports 33 being spaced axially outwardly from the fluid intake ports 35 so as to be open when a corresponding disc valve 22 is in its inward position wherein it closes its corresponding inlet port 35 and to be closed when the corresponding disc valve 22 is in its outward positlonwherein it opens its corresponding intake port 35.

A power transmitting fluid such as oil or water enters at one end of the cylinder block through a pipe 33 and is herein shown as being discharged at the same end of the block through a pipe 33.

The inlet pipe 33 connects with an inlet passage 40 running through almost the entire length of the block, while the discharge pipe 33 is connected to a similar passage 4| on the opposite sideof the block from passage 40. Each passage is connected to the outer end of each pump cylinder by branch passages; these branch passages being numbered 43, 44, and 46. In branches 43 and 44 are check valves 41 that prevent flow of fluid from the two pump cylinders back into the inlet passage 40; and in branches 45 and 46 are check valves 48 that prevent fluid from flowing back into the pump cylinders from the outlet or discharge passage 4|.

The unit is adapted to be supplied by a motitvatlng fluid under pressure such as compressed Assuming the parts to be in the positions which they occupy in Figs. 3 and 4, when air under pressure is admitted into the supply pipe 3| it flows through the inlet port 34 and through the intake port 35 into the valve chamber 2| at the lefthand end of the power cylinder II to thereby "exert pressure upon the left-hand annular face of the motor piston 23 and consequently forces the motor piston 23 toward the rightbecause the air under pressure which is disposed between the motor piston 23 and the left-hand valve 22 cannot escape through its corresponding exhaust port 33 into the atmosphere through the outlet port 31 since the exhaust port 35 is, at this period, closed by the left-hand valve 22; the pressure of the springs 25 being insuflicient to displace the left-hand valve 22 from such position while there is air pressure between it and the motor piston 23.

In the movement of the motor piston 23 toward the right, air, under atmospheric pressure within the cylinder I1, is forced out of same through the openings. 24 in the right-hand valve 22. into the right-hand valve chamber 2| and through its corresponding exhaust port 33 and its outlet port 31 into the atmosphere thereby relieving the motor piston 28 from any objectionable back pressure. The right-hand valve 22 is retained in its inwardmost position, as shown in Figs. 3 and 4, due to the pressure of the springs 25 and thus maintains its corresponding exhaust port 36 open and its corresponding intake port 35 closed and these exhaust and intake ports remain in such condition until the right-hand valve 22 is forcibly engaged by the hub 33 of the motor piston 23, as it moves toward the right, and is moved against the pressure of the springs 25 into its outermost position whereat its corresponding exhaust port 36 will be closed and its corresponding intake port 35 open. During such movement of the motor piston 23 toward the I right, the piston of the left-hand valve 22 will, for a period of time, remain unchanged since the pressure of the motivating fluid between the left hand valve 22 and the motor piston 23 is suftlcient to over-come the comparatively weaker pressure of the springs 25 to displace this valve.

Also, during such movement of the motor piston 23 toward the right, and because the pistons 21 and 29 are connected by shaft 25 with thepiston 23, to pump fluid under pressure through the discharge pipe 33and this pumping action results as follows:

With the parts positioned as shown in Figs. 3-

and 4, when the piston unitmoves toward the right, the pump piston 23 forces the fluid out of cylinder I3 into passage 4|, the local check valve 41 preventing the return flow of the fluid into passage 43. While this is happening, check valve- 41 at the opposite end of the unit permits oil to flow from passage 40 through checkvalve 41 and passage 43 into pump cylinder l5 behind the rebeen started.

the latter.

treating piston 21. As the piston unit reaches the right-hand limit oi its movement, the righthand hub 30 on the power piston 28 strikes the right-hand valve 22 and forces it outwardly thereby closing the right-hand exhaust port 36 and opening the corresponding intake port 35.

At this time, also; left-hand pump piston 21 engages the left-hand valve 22, forcing it to the right and closing its corresponding intake port 35 and opening its corresponding exhaust port at theleft-hand end of the power cylinder. Air under pressure now enters the right-hand end of the power cylinder; while that in the left-hand end escapes into the atmosphere; the fluid in pump cylinder l6 being forced out into passage 4|.

' 29 fromlcylinder l8 through passage 46 and its associated outlet check valve 48 into the discharge passage 4| and out through pipe 39 to its place of use, the fluid under pressure in cylinder I8 is prevented by inlet check valve 41 from being pumped back into the fluid inlet passage 40. When fluid under pressure 'is being pumped by pump piston 21 from cylinder l6 through passage 45 and its associated outlet check valve 48 into the discharge passage and out through pipe 39 to its place of use, the fluid under pressure in cylinder I6 is prevented by the inlet check valve 41 from being pumped back into the fluid inlet passage 40. It will be evident from this description of the operation, that the'necessary movements of the -disc valves 22 are caused by their alternate engagements'by the coacting pistons 21, 28 and 29 i of the piston unit, and that such valve movements "because the motor piston 28 holds each such valve 22 in such position until the power fluid itself enters between the motor piston 28 and "such valve and thereafter holds thev valve against shifting-until the finish of a stroke that has thus It willthus be seen that I have produced a simple-novel and rugged combined fluid-operated motor and pump. that makes possible the pumping of water or oil emciently at high pressure and low pressure and .when the load is light as well'as during peak loads, by simply maintaining a supply of the motor'fiuid or air under pressure that is replenished during the periods between peak loads and the pressure of which, as it reaches the motor, being adapted to be regulated by valves over a rangeas wide as is needed; the size of the fluid-operated motor depending solely on the ratio desired between the pressure of the fluid entering the motor and the pressure of the pumped fluid and not on the absolute pressure 01 While I have illustrated and described with particularity only a single preferred form of my invention, I do not desire to be limited to the precise details thus illustrated and described; but

. 6 intend to cover all forms and arrangements that come within the definitions of my inventionconstituting the appended claims.

I claim:

1. In a combined fluid-operated motor and pump, a cylinder block containing three axially aligned piston cylinders opening into each other, the central cylinder constituting the motor cylinder, being larger in diameter than theothers which are pump cylinders, a rigid piston device containing three pistonsspacedapart from each other and each fitting slidably in one of said cylinders, said cylinder block containing a powertransmitting fluid inlet passage and a discharge passage each of which is connected to both of said pump cylinders, check valves in said passages. to prevent a flow of fluid from the pump cylinders into the inlet passage and from the discharge passage into the pump cylinders, said cylinder block also containing an inlet port and an outlet port for motivating fluid at each end of the motor cylinder, and means, including disc valves forming partitions between said cylinders and movable by said piston device, to, open andclose said inlet vating fluid under pressure is alternatelypassed v each containing a piston cylinder axially aligned with the others, the central cylinder constituting the motor cylinder, being larger in diameter than and opening into the others which are pump cylinders, the sections being shaped to produce a wide internal annular chamber coaxial with the cylinders and larger in diameter than the motor cylinder and disposed between the latter cylinder and each of the pump cylinders, a rigid piston device having thereon three pistons spaced apart from each other and each fitting slidably in one of said cylinders, said block containing a power-transmiteach of which is connected to both of said pump cylinders, check valves in said passages to prevent a flow of fluid from the pump cylinders into the inlet passage and from the discharge passage into the pump cylinders, said block alsocontaining a pair of inlet ports for motivating fluid, one for each of said chambers, an outlet port for each of said chambers, disc valves, thinner than the depth of said chambers, fitted slidably on the piston device and slidable in said chambers, each disc being adapted to be shifted into one position to open its corresponding inlet port and at the same time close its corresponding outlet port and upon being shifted into opposite position to close its corresponding inlet port and at the same time open its corresponding outlet port, and elements on the piston device to shift the discs in the proper sequence to cause the piston device to reciprocate diameter and constituting pump cylinders, a disc in each end of the motor cylinder and covering the inner ends or the pump cylinders, said discs being 7 sponding disc is at one limit of its movement and the other is closed when the disc is at the other limit of its movement, the discs being perforated at a distance from the axis of the cylinders greater than the radius of the pump cylinders, and elements on said shaft adapted to shift said discs back and forth when fluid under pressure is available at said inlet ports.

5. A pump as set forth in claim 4, and including resilient means for each disc yieldingly urging the disc into position wherein the outlet port is open and the inlet port is closed.

6. In combination, a cylinder block containing a power cylinder, members closing the ends of said power cylinder and each provided with a cylindrical chamber coaxial with and of larger diameter than said power cylinder, a disc that is substantially thinner than the depth of said chamber fitting slidably in each such chamber, said cylinder block containing at each chamber an inlet port and an outlet port 50 located that one port is closed and the other open when the corresponding disc is at one limit of its' axial movement=and the conditions are reversed when that disc is at the opposite limit of its movement, each of said.

\ cation between the cylinder and the remote end of its corresponding chamber, a reciprocatory piston in said power cylinder, and means connected with said piston adapted to shift both discs as said piston reaches the ends oi. its reciprocatory movements. i I

,7. The combination as set forth in claim 6, and including resilient means for yieldingly holding the discs in the positions wherein the outlet ports are open.

I 8. The combination as set forth in claim 6, wherein said inlet ports are disposed at the ends of the chambers adjacent the power cylinder, and said outlet ports are disposed at the opposite ends of the chambers, and wherein each disc contains at least one opening through the same to provide a path for exhaust fluid to said outlet ports when each disc has closed its corresponding inlet port.

' HERBERT J. WERNER.

REFERENCES CITED The .following references are of record in the file of this patent:

,Great Britain 1864

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