US2495319A - Hydraulic pump - Google Patents

Description

Jan. 24, 1950 w. P. FERRIS EIAL HYDRAULIC PUMP 3 Sheets-Sheet 1 Filed Sept. 7, 1946 Jrtzerz w 5. v I

Jan. 24, 1950 w. P. FERRIS ETAL HYDRAULIC PUMP 5 Sheets-Sheet 2 Filed Sept. '7, l946 HYDRAULIC PUMP 5 Sheets-Sheet 3 Jan. 24, 1950 w. P. FERRIS ETAL Filed Sept. 7, 1946 fwd/ 5 275.; y a ra f5 Jig/6295021- Fri II. n

Patented Jan. 24, 1950 UNITED STATES PATENT OFFICE HYDRAULIC PUMP William Paul Ferris and Nevin J. Blum, York, Pa.,

by mesne assignments, to Karl Wihtol, Middletown, N. J., mam; as wuitol Industries Application September "I, 1946, Serial No. 695,484 7 Claims. (01. 103-11) An object of the invention resides in providing a portable hydraulic pump capable of being conveniently and readily ported to advantageous positions or relation to jobs" and of being wholly and efiiciently manually operated and controlled in such operation by the foot of a worker, thus freeing the artisans hands for use in the handling and working of apparatuses and devices connected to the pump and receiving operating power therefrom, thereby effecting highly desirable and manifest economies and reducing labor requirements to a minimum.

It is also an object of the invention to provide a portable hydraulic pump of compact, durable and simple construction, in which the manual operating means therefor, when not in use, will be most advantageously arranged and retained in an out-of-the-way position with relation to the body of the device, and at the same time, will provide to the pump a cover for housing and protecting the vital working and other parts thereof against damage, as by the contact of foreign objects therewith, rough handling, and the deposit and accumulation of foreign matters (dirt, grease, etc.) thereon; hence, maintaining the construction at its peak operating efllciency.

The invention also aims to provide a pump of the stated character, wherein the pump units of its working assembly may be operated to pump fluid therefrom at extremely light pressures (of approximately 100 pounds per square inch and under), and high velocities for rapid movement of operated devices (jacks, rams, etc.) to a point contacting the work load (of more than approximately 100 pounds per square inch), and will,

upon contacting said work load, cause an automatic switch-over of the pumping units so that the pressure of the output or pumped fluid is suitable for heavy duty operation but at a lower velocity, or if desired, the automatic switch-over may be selectively discontinued, under which latter operating condition, it will be possible to obtain pumped fluid pressures of only sufllcient" force for light or reasonablylight duty worksay, work entailing loads up to approximately two tons or 2300 pounds per square inch, but will be constant and unchanging with the resultant advantage of continued high velocity for all loads within this range.

In a prefatory sense, it may be stated that portable hydraulic pumps have been employed for developing and transmitting power for various uses. In particular, pumps of this character have been and are now being used, with varying degrees of success, to supply operating power to tools (both compression and tension) rams whose plungers are constructed and equipped to receive and operate appliances, devices and tools for doing various kinds of work, lifting and supporting jacks, etc. A considerable use of such equipment is made in the automotive industryautomobile repair work-in which hydraulic rams are extensively employed to operate different designs and types of metal working tools, advantageous for automobile-body, chassis, fender and top repair, 1. e., where such members or parts have been deformed, by collision or otherwise, and must be reshaped, straightened and otherwise repaired to their original condition and form.

The hydraulic pumps used for operating equipment of the above kind, are open to various objections, amongst and foremost of which is the fact that two and sometimes more men are required to do a repair job with a machine employing the same-one to operate the hydraulic pump and one or more to handle and operate the tool equipped hydraulic ram. Additionally, the hydraulic pumps heretofore used as power developing and supply means for straightening and reshaping assemblies or machines, as above, are unsatisfactory in that inadequate control of the ram operated tool equipment is experienced, to the end that the extent of compression or tension movement and return movement to starting or initial position of the tools and the ram plunger, cannot be accurately and conveniently effected. Furthermore, the body design of these hydraulic pumps has been faulty, permitting of oil pressure leaks with incident loss of operating efliciency due to improper assembly, and susceptible to parts damages or breakage because of their unprotected placement and the rough usage to which they are subjected; plus, serious impairment of parts operation through the deposit and accumulation thereon of foreign matter, such as dirt, grease, etc.

, The pump of our invention will eliminate and/or.

I hydraulic ram connected thereto.

The foregoing, as well as other objects, advantages and meritorious teachings of our invention, will be in part obvious and in part pointed out in the following detailed disclosure the pump body broken away to illustrate the tapped hole for fitting or attaching an oil conveying conduit (not shown), whereby pressured oil will be conducted to an apparatus or devic to be operated by the pump.

Figure 2 is a side elevation of the same, with a dotted line showing of the foot operated ,lever in open or upper position.

Figure 3 is an enlarged fragmentary sectionv taken longitudinally through the housing, pumping units, valves and operating lever of the pump assembly, wherein the lever is shown in its closed or lower position, and the pump pistons in their respective lower positions.

Figure 4 is an enlarged longitudinal fragmentary section through an end portion of the pump housing and the operating lever (the operating lever in itsclosed or lower position), illustrating the foot engaging or pedal portion of the lever and the manner in which the same engages over and protects or shields adjacent portions of said housing, plus, the means for releasably securing the lever in its closed or lower position.

Figure 5 is a fragmental section taken on the line 5-5 of Figure 3, looking in the direction in which the arrows point.

Figure 6 is an enlarged vertical transverse section, taken on the line 66 of Figure 2, looking in the direction in which the arrows point, and

Figure 7 is a fragmentary plan section taken approximately on the line 1-1 of Figure 4, looking in the direction in which the arrows point.

Referring in detail to the drawings, the invention, generally stated, comprises a one-piece pump and valve body I of substantially elongated rectangular formation-preferably, heat treated aluminum alloy impregnated casting, thus, eliminating leaks, i. e., leakage of oil and pressure at threaded and similar joints, common in the assembled types of constructions now prevalent; a combined operatinglever and cover 2 hingedly end mounted on one end of the body I engageable with and over the same, at times; a pump cylinder bed or block 3 within the body i; an oil reservoir or box 4 (hereinafter more fully described) within the body i adjacent to and communicable with pump cylinders in the bed or block 3, and a release lever 5 on said body I having a trip-pedal portion extended angularly therefrom to facilitate its engagement for operation.

The body i is formed with upstanding side and end walls. An intermediate portion of the body has an integral transverse wall therein extending forwardly and obliquely of the inner end of the bed 3, as at 6, contiguous with portions of the normally forward end and side walls of said body,

whereby to provide therebetween the aforesaid liquid or oil reservoir 4. A cover plate I is engaged over the opening defined, as above, and is detachably secured to adjacent portions of said walls by engaging connecting screws 8 through appropriate openings therein in screw-threaded openings in the plate contacted portions of said walls, asshown in Figures 3 and 4 of the drawings. An internally screw-threaded filling opening is formed in a forward portion of the cover plate I to facilitate the entrance of oil into the reservoir 4 and is normally closed by a threaded plug 9 carrying a dependent oil level measuring gauge IO extending into the oil reservoir 4, for an obvious purpose. Suitable packing II and I2 is preferably arranged between the cover plate I and adjacent portions of the reservoir walls and the plate and plug 9 to prevent leakage thereby.

A milled upstanding lug I2 is fixedly mounted on the upper face of the forward portion of the cover plate 1 and cooperates in a manner, hereinafter described, to releasably lock and secure the free end of the operating lever 2 in its lowermost or closed position with relation to the body I.

The combined operating lever and cover 2 is preferably of one-piece construction, of length, width and configuration substantially corresponding to the open upper side of the body I so that when the same is in its lowermost and closed position, it will overlie said side of the body I in the manner shown in Figures 1 and 2. The memher 2 is generally inverted U-shaped in cross section. Its rearward end portion is upwardly extended or domed, as at ll, while its forward end portion is also slightly domed, as at i 5, and preferably, has its outer face roughened or similarly treated, to provide an effectual pedal-like part adapted to be engaged by a foot of a user for facilitating operation, i. e., pivotal or swinging movement.

To pivotally mount the lever 2, the rearward and domed portion ll thereof is provided with suitable transversely aligned bushings i6 adapted to receive and revolve on a hinge-pin li removably, though securely, mounted in an adjacent boss I! on the body bed 3 and engaging in the side walls of the body (see Figures 1 and 3).

Pivotal or swinging travel of the lever 2 beyond predetermined limits at each end of its extreme movement (fully closed and/or fully extended positions) is prevented by the striking of the pedal part 15 against the pump valve body at the point II, when closed, and when in its raised or uppermost position, as shown in dotted lines in Figure 2, by the abutting or striking of a boss l8 against the mounting I! for the hinge-pin l'i.

Upward swinging travel of the lever 2 to the position shown in dotted lines in Figure 2, is normally urged by the action of a tension spring 20, one end of which is secured to the body I through the pin 2| driven into an appropriate portion thereof, while its remaining end is engaged with a lug 22 cast integrally with the rearward end of said lever 2. Thus, when under tension, the spring 20 swings the lever 2 about its hinge-pin l1, causing said lever to assume the dotted line position shown in Figure 2.

In order that the lever 2 can be releasably locked in closed or lowermost position with relation to the body I, as shown in full lines in Figure 2 of the drawings, a locking device is provided to the under side of the pedal part I5 thereof. This comprises a pin or cylindrical element 23 of greater length than the width of the pedal part II, disposed transversely of the pedal part (see Figures 6 and '7) and snugly though slidably received in suitable bearing openings in its (the pedal part) sides. Relatively spaced circumferential grooves 24 and 25 are formed in one of the end portions of the pin 23 and the opposite end portion thereof has a groove 26 milled therein parallel to its axis. Spring loaded ball checks 2'! aaaaa o and 28 are seated in portions of the pedal parts .side walls adjacent said pin bearing openings upon the relative positioning of the pin 23,,and

the ball check 28 is constantly engaged in the coaxially disposed groove of said pin. The ball check 21 movably retains the pin 23 in either of its two positions, as indicated in Figure 6, while the ball check 28 prevents said pin from turning on its axis.

- An intermediate portion of the slidable locking device pin 23 is cut away, as at 29. The length of said cut-away portion substantially corresponds to the width of the milled upstanding lug l3 on 1 the cover plate 1. Thus, when the pin is slid to a position where the groove 24 is engaged by the ball check 21, its cut-away portion 29 will align with or clear the lug l3, and upward swinging of the lever with the pin moving freely by said lug will be permitted. However, when the pin 23is slid to a position where the groove 24 is disengaged from the ball check 21 and its groove 25 is engaged thereby, the cut-away portion 29 will .be

disaligned from the milled lug l3, i. e., causing- "covered and thereby protected by said pedal part.

Referring now to the duo-pump cylinders in the pump cylinder bed or block 3, tandemly arranged,

obliquely and rearwardly disposed and opening cylindrical bores are provided in said bed, as shown in Figure 3 of the drawings. Tubular steel liners 30 and 3i are pressed into the cylindrical bores. ably receives a, high-speed plunger 32 and that provided with the liner 3|, slidably receives a power plunger 33. Each of the plungers 32 and 33 has downwardly opening milled slots 34 on their exposed and upper ends. slots are engaged by pins 35 and 36 carried by brackets 31 fixedly mounted on appropriate portions of the under side of the rearward domed portion l4 of the lever 2. Thus, when said lever swings into the raised or upper position, heretofore described (the dotted lines showing in Figure 2), the plungers 32 and 33 being now connected to the lever 2, are moved outwardly from their respective cylinders, causing oil to be drawn through the hereinafter described valve system into the pump cylinders, constituted by the tubular liners 30 and 3|, preparatory to performing the pumping operation.

The high speed plunger 32 is preferably pro,- vided with a hard chrome plated and highly polished surface and, as described, slides or reciprocates in the tubular steel liner 30, pressed into the pump and valve bed 3. Said plunger is equipped on its inner end with standard cup.- leather packing 38, and on its outer end with compression or wiper-ring packing 39. Suitable washers and a lock nut 40 are engaged with a reduced screw-threaded end portion on the plunger inner end, whereby to properly position and secure the packing 3B. The compression packing 39 is held in place and adjusted by means of a packing nut 4| threadedly engaged in and with an enlarged portion of the cylinder bore in the bed 3, which also serves as a guide bearing for the plunger 32.

The bore provided with the liner 30 slid- These 6 The power plunger 33, too, ispreferably provided with a hard, chrome plated and highly pol- .ished surface and is reciprocally received in the tubular steel liner'3l. It is desirable that the plunger 33 be provided with chevron or V-type packing 42 adjusted and retained in place by -means of a packing nut 42 threadedly engaged in an enlarged portion of the cylinder bore beyond its liner 3i. The nut 42' also serves as a guide bearing for the plunger 33.

As previously described, both the plungers 32 and 33 are connected to the operating lever 2, and an alternate pressure applying and releasing to A the pedal part l5 thereof causes reciprocation of said plungers in their respective cylinders.

Oil for the high speed pump, constituted as 'above, is drawn from the oil reservoir 4 through ,the way 43 in the bed 3 through a strainer 44, aclearly shown in Figure 5 of the accompanying drawings. Upward movement of the plunger 32 in its cylinder, imparted thereto from the upwardly swinging operating lever 2, creates a suction causing an intake ball check valve 45 to be moved off its seat 45', overcoming the slight pressure applied thereto by a coiled spring 46 arranged in a duct or way 41 in and transversely of the bed 3 communicating with the way 43 in said bed and with the lower and adjacent end of the high speed pump cylinder, in a manner hereinafter more fully described. Thus, oil will be allowed and caused to flow freely past the ball check valve 45 into said high speed pump cylinder.

.On the downward stroke of the plunger 32, the intake valve 45 is forced against its seat 45', preventing oil from returning through the way 43 to the reservoir 4, but permitting oil to escape through a. discharge ball check valve 48, seated at 48', in. an opposite end portion of the duct 41 .by pushing the same from its seat. The pump expelled and pressured oil escapes from the opposite portion of the duct 41 in a duct 49 in and longitudinally of one side of the bed 3, passing into and through a port 50 also in the bed and disposed transversely thereof, which port 50 con- .nects to a, port 5|v (see Figure 3) in the bed 3. finally, passing out through a port 52 (see Figure 3) in said bed, which latter port is an extension of the tapped. hole 53, shown in Figure 1 of the drawings, serving as an outlet to the oil conveying conduct (not shown) of an apparatus or de- .vice to be hydraulically operated by the pump, such as a ram, etc. (also not shown). Simultaneously, the oil for the power pump and its plunger 33 is likewise flowed through its intake and discharge ball check valves 54 and 55 and strainer 44', duplicating the high speed pump intake and exhaust valves 45 and 49 and strainer 44, and also, connected to or communicating with the -ports.49, 50, 5| and 52.

Threaded plugs 55 and 51 are engaged in the opposite ends or intake and discharge portions of the ducts 41 of the high speed and power pumps for closing the same and, as a means for permitting access to the intake and discharge valves :housed therein, for repair, replacement, eto. Likewise, threaded plugs 58 and .59 are engaged in the ends of the respective ports 50 and 5|, for closing them.

, In order that oil will always return from an apparatus or device connected to our improved pump and operable thereby, preparatory to start.- ing another operation, especially, a hydraulically operated ram of standard or other construction (not shown), we provide the pump with a release valve. Said release valve.v it may be now stated,

is maintained in its open position when the operating lever 2 is in the lowermost or closed position with relation to the body I, as shown in full lines in Figure 2. This is accomplished by reason of the fact that when said lever is'in its lowermost position, as above, a cut-away portion 66 in and intermediately of one of its sides, will receive and engage a portion of the hereinbefore generally referred to release lever 6 in a manner to be held on said seat by the pressure of a compression spring 64 in the duct 6| and the action of the oil pressure working against and tending to seat the ball valve. With the ball unseated, oil returns from the pump operated apparatus or device (ram, etc.) through the port 52 via the conduit engaged hole 63 in one side of the bed 3,

past the release valve seat. The lower and reduced end 65 of the release valve stem 65, which contacts the ball valve 63, is formed with milled flats so that when said ball valve is unseated, oil can and will escape around the release valve stem into a port 66 from where it will have free passage through an outlet or small duct or 011 return way 61 into the reservoir 4. Unseating of the ball valve 63 is effected by havin the cut-away portion 60 of the operating lever 2 engage an extended and adjacent portion of the release lever 6, thereby causing the latter to swing about its axis on a mounting screw 68 or like device supported on a portion of the pump bed 3 (see Figure 3), causing a downward motion of the adjustable striking r tappet screw 69 carried thereby, whereupon said screw engages and downwardly moves the release valve stem 65 to unseat the ball valve 63. As previously stated, the ball valve 63 is normally held on its seat by the combined pressure of the compression spring 64 and the oil pressure working against the same. Thus, with the ball valve 63 unseated, oil returns from the ram or other pump operated device, etc., through the outlet port 52, by way of the tapped hole 53, past the valve seat and then into the reservoir 4.

As and when the operating lever 2 is unlocked with relation to the milled lug 13 on the body I, heretofore described, and allowed to swing upward underinfiuence of the tension spring 20 to the dotted line" position shown in Figure 2 of the drawings, the release lever 6 is disengaged by the portion 60 of the operating lever 2 to allow the compression spring 64 to reseat the valve 63 and move the release valve stem 65. This, in turn, returns the release lever to its free position.

A gasket 10 interposed between the valve seat 52 and the bottom of the receiving bore, prevents leakage around said seat, while suitable packing H in said bore adjacent the release valve stem prevents leakage thereabout. A packing nut I2 serves thedual purpose of providing tension and adjustment for the packing H, and also, to act as a, guide bearing for the release valve stem 65.

Under certain operating conditions, it will become desirable to operate the release lever 5 man ually, rather than more or less automatically from the spring operating lever 2. That such manual operation may be efl'ected, the free end of said release lever is provided with a fixed and laterally extended pad or finger 13, which, as shown in Figures 1 and 2 of the drawings, extends from and beyond an adjacent side a: the body I. Thus, by depressing the finger 13, the release lever 5 will be operated irrespective of the swinging operating lever 2. Usually, it will be more convenient to release or operate the release lever 5 from the operating lever 2 as a continuation 01 the pumping motion which is required to apply hydraulic pressure to a ram or other device connected to the pump. However, there will be times of usage when the hydraulic pressure has been built up, while at the same time, the foot operable lever 2 may be anywhere between the extremities of its swinging movement. At such times, the additional travel of said lever 2, necessary for operating the release lever 5 thereby. would cause an undesirable movement of the ram. In this instance, a user's foot need only be removed irom the operating lever 2 and engaged and pressed downwardly on the finger extension 13 to operate the release lever 5 for releasing all pressure from the ram or other operated device, etc., and causing oil to be returned to the reservoir 4, as heretofore described.

, To by-pass oil from the high speed pump of the invention assembly directly to the oil reservoir 4, rather than pump the same to a ram or other device connected to and operable by said invention, as when a load of 100 pounds per square inch, or greater, 5. capacity or near capacity or intermediate load is handled or encountered by said ram in its work performance, and thus, permit only the oil pumped from the power pump unit (heretofore described) to be delivered to the ram, we provide an oil by-pass valve. This bypass valve is received in an oblique forwardly and longitudinally disposed bore formed in the body I forwardly of though juxtapositioned with relation to the high speed pump unit. The bore is internally screw-threaded for a greater portion of its length and communicates with the intake portion of the port 41, hence, with the high-speed cylinder thereof, via a port 14 leading from the bore bottom and cutting into said portion of the port 41, at 15 (see Figure 5 of the drawings). A valve seat 16 is screw-threadedly engaged in the bore, ported as at 11 and having a plurality of circumferentially disposed ways 18 formed in and intermediately of its opposite ends. The bypassing valve seat 16, as will be observed on reference to Figure 3 of the drawings, is threaded to receive and retain therein the by-pass spindle 19 which, in turn, houses the by-pass valve 80. The by-pass valve 60 is held against the seat, 1. e., ad-

.Jacent its port 'l'l, by a predetermined spring load provided by a compression spring 8| about the valve stem engaging the valve proper and arranged within the spindle 19. Said compression spring, in addition to maintaining the by-pass valve on its seat, keeps it there at all times until the pressure working through the port 11 is sumcient to overcome the spring load. When this point is reached (the by-passing pressure of the oil) and the valve is unseated, oil flows past the seat through the small ways 18 therein out into the space indicated at 82 and from the same, via a port 83 communicating with the small duct 61, into the oil reservoir 4. Suitable packing 84 about the by-pass spindle 19 and a packing nut .6, turned into the outer end of the bypass valve receiving bore, prevents oil from leaking to the outer surface of the bed 3. A friction thimble 66 at the upper or outer end of the by-pass valve wives to prevent noise caused by action of the va ve. placed by the high speed plunger 32, after it reaches a predetermined pressure, must pass through the by-pass valve. Since the size of said valve is restricted, due to the necessity of space and weight conservation, resulting difliculty or annoyance with or by noise caused by the surging action of the by-pass valve is eliminated by the On each pump cycle, all of the oil dis- 83 (operated collectively with tire high speed plunger 32) reaches the ram or other device, etc., comiected to and operated by the pump, and is prevented from by-passing by means of the high speed plunger discharge valve and seat 4048' in its particular duct or way 41.

Our improved hydraulic pump assembly is designed to operate at a maximum pressure of approximately 9,000 lbs. per square inch, which, when used in conjunction with the ram unit (not shown) designed for the purpose, would result in a rated capacity load on said ram of ten tons. A majority of the times when the ram unit may or will be used in the repairing of wrecked automobiles, etc., this ten-ton working load is not required and would normally result in an unnecessary low speed on jobs entailing only light loads to the ram unit. Since this is the case, the bypass valve is constructed in such a manner that its by-pass action may be eliminated entirely, so that at all times, the oil from both pump plungers 32 and 33 (oil displaced thereby) is forced into said ram unit. With the pump used in this manner, pressures of approximately 2,300 lbs. per

' benefit of the high ram speeds, at all times.

In order to accomplish the above results, the by-pass valve 80 is held on its seat 16 by revolving or turning clockwise the screw-threadedly valve seat engaged by-pass spindle 19 (see Figure 3) until it contacts a shoulder 88 on the by-pass valve (its stem) 80, which holds this valve rigidly on its seat, preventing any oil from by-passing the same. The action ofthe pump plungers, valves, etc., otherwise is identical with operation of the pump when no load is applied to a ram unit or other apparatus or device connected to or operable therefrom.

During operation of the pump plungers 32 and 33 with no load on 'a ram unit, apparatus or other device connected to and operable by the pump, other than that caused by frictional resistance and other incidental stresses, the bypass valve 80 remains engaged or seated on its valve seat It and may be ignored as effecting the operation of the unit. Manifestly, during these operations, the spring loaded release ball check valve remains seated on its respective seat 62 and prevents oil from escaping or flowing through 10 the port 52, except as previously described, out through th tapped hole or hose receiving connection U3.

The by-pass valve, hereinbeiore described, allows an operator to use an operating speed and capacity to suit the particular occasion or job. With the valve in an "operative position," the pumping motion of the operating lever 2 will deliver hydraulic pressure to a to-be-operated apparatus or device at high speedas in the case of a hydraulic ram, the plunger of the ram will be forced out quickly until the work is contacted; then, the duo pumping means of the in vention automatically changes from high speed to low speed so that, if necessary, a ten ton effort may be exerted on the ram with a minimum amount of effort. If the by-pass valve is given two or three turns clockwise, the duo-pumping means, aforesaid, will operate at high speeds constantly and be capable of pumping a load of approximately two tons on the referred to ram. This position will promote the maximum efficiency for most work operations where only light loads are encountered and the accompanying higher speeds of the high speed pump are desirable.

A hydraulic pump constructed in accordance with the teachings of our invention permits of its convenient, easy and efficient operation by the foot of an operator. Thus, the operators hands are free for other work, such, for example,

as holding a hydraulic ram and attachments during the entire setting-up, pumping and releasing operations. This feature is of prime importance in that when th pump is employed as a source of hydraulic power in a metal working assembly, such as used in automobile repair work (chassis, body, fender, etc. straightening), a oneman operation of the units of the assembly is entirely feasible and practicable. Therefore, the need for a second man :or assistant for working the pump is entirely eliminated.

Additionally, because of the compact, light, and hence advantageously portable characteristics of the improved pump, the same may be easily and practicably arranged or supported in various and unusual positions with relation to a "10 and satisfactorily operated. In such positions or arrangements of the pump, it may be desirable that the operating lever 2 of the same be hand, rather thanfoot. operated. In others, it may be operated by both hand and/or foot, whichever mode of working makes for greater efliciency and operating satisfaction.

By reason of the operating lever locking feature of the invention, whereby said lever can be swung downwardly into parallel arrangement and locking engagement with the pump body, the resultant compactness of the assembly makes for convenience in its storing in limited and possibly out-of-the-way places. Moreover, by covering the upper side of the pump body when the operating lever is in its closed or lowermost position, the protection of adjacent and exposed par-ts against damage thereto and foreign accumulations thereon will be effected, thus, maintaining an overall operating eiiiciency.

We claim: g

1. In a hydraulic pump, an elongated and relatively narrow body having side and end walls, a pump bed in a portion of the body, a reservoir in the body juxtaposed with relation to said pump bed and communicable therewith, the upper side of said reservoir being open, a cover plate ensaged over the open side of the reservoir, keeper means on a portion 01' said cover plate, a combined cover and operating lever of shape and size substantially corresponding to the configuretion of said body swingably mounted on the body connected to pumping means received by said bed, said combined cover and lever being engageable, at times, over the reservoir and bed in the body, the opposite end portions or said combined cover and lever having domed portionsiformed therein, one engageable over the pump bed of the body and the other engageable over a portion of the cover plate and keeper means thereon when said combined cover and lever are engaged over the reservoir and bed in said body, means on one of the domed portions of the combined cover and lever releasably engaging the keeper means on the cover plate for locking the combined cover and lever to the body, and other means engag 1 ing the combined cover and lever for normally imparting the outward and upward swinging movement to the same with relation to said body upon disengagement from said keeper means. 2. A hydraulic pump, comprising a body, high speed and power pumping means on the body having a common fluid outletting and return way communicating therewith and formed in said body, a reservoir in the body having valved communication with the high speed and power pumping means, an adjustabl pressure actuated by-pass valve in the body interposed between the reservoir and the high speed pumping means and communicable therewith, said pressure actuated by-pass valve being operable upon the attainment of a preselected pressure of fluid pumped by said high speed pumping means to by-pass the same from its discharge port communicating with said outletting and return way directly to said reservoir, and an operating means swingably mounted on said body connected to said high speed and power pumping means.

' 3. A hydraulic pump, comprising a body, high speed and.power pumping means on the body, a reservoir in thebody juxtaposed with relation to said pumping means having a common fluid outletting and return way communicating therewith formed in said body, a pressure'actuated bypass valve in the body interposed between the reservoir and the high speed pumping means 7 and communicable therewith, said pressure actuated by-pass valve being operable upon the attainment of a preselected pressure of fluid pumped by said high speed pumping means to by-pass the same from the discharge port of the high speed pumping means communicating with said common fluid outletting and return way in said body directly to said reservoir, other valve means in the body communicating with the fluid outletting and return way of said pumping means and said reservoir for by-passing fluid from said way directly to the reservoir by said high speed and power pumping means, manually operable means on the body connected to said high speed' slotted portions on the upper ends of each of said plungers, manually operable means swingably mounted on the body in proximity to one of its and power pumping means for operating the same, a lever mounted on the body engageable with said second mentioned fluid lay-passing means for opening the same, a portion of said lever being disposed in the path of travel of said manually operable means for engagement thereby at a predetermined point of its swinging travel, and another portion of said lever being disposed with relation to said body for manual engagement.

4. A hydraulic pump, comprising a body, a pinrality of pumps mounted in the body in tandem relation and obliquely and rearwardly disposed ends and said pumps mounted therein, and means on portions of the manually operable means pivotally and loosely engaged in the slotted portions of the upper ends of each of said plungers.

5. A hydraulic pump, comprising a body, a plurality of pumps mounted in the body in tandem relation, each of said pumps being obliquely and rearwardly disposed with relation to said body. each of said pumps including reciprocal plungers working in their respective cylinders, a reservoir in the body having valved communication with" said pumps, inwardly opening slotted portions onl the upper ends of each of said plungers, manually operable means swingably mounted on the body in, proximity to one of its ends and the pumps mounted therein, means on portions of the manually operable means pivotally and loosely engaged in the slotted portions of the upper ends of said plungers, and other means engaging said manually operable means for swinging the same upwardly and outwardly from the body preparatory to and following a manual operation of the same.

6. A hydraulic pump, comprising a body, a pinrality of pumps mounted in the body in tandem relation and obliquely and rearwardly disposed in relation to said body. each of said pumps having reciprocal plungers in their respective cylinders,

I a reservoir in the body having valved communication with said pumps, manually operable means swingably mounted on the body in proximity to one of its ends and to said pumps, and means connecting the manually-operable means to the plungers of each of said pumps whereby to impart sliding motion to the plungers with swinging of the manually operable means away from and towards said body.

7. A hydraulic pump, including a body, high speed and power pumps in the body in tandem relation, said body having a fluid outletting and return way formed therein and co mmon to said pumps, a reservoir in the body having valved communication with said pumps, an adjustable pressure actuated by-pass valve in the body interposed between the reservoir and the high speed pump and communicable therewith, said pressure actuatedby-pass valve being operable with the attainment of a pre-selected pressure of fluid" pumped by said high speed pump to by-pass the same from its discharge port communicating with said outletting and return way directly to said reservoir, and means connected to said high speed and power pumps for operating the same.

' WILLIAM PAUL FERRIS.

NEVDI J. BLUM.

' REFERENCES CITED The following references are of record in the file of this patent: 1

UNITED STATES PATENTS

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