US2337831A

US2337831A - Pump for hydraulic systems

Info

Publication number: US2337831A
Application number: US453334A
Authority: US
Inventors: Harold J Mcgovern
Original assignee: Individual
Current assignee: Individual
Priority date: 1942-08-03
Filing date: 1942-08-03
Publication date: 1943-12-28
Anticipated expiration: 1960-12-28

Description

M Cfltorneg H. J. MOGOVERN Filed Aug. 3} 1942 PUMP FOR HYDRAULIC SYSTEMS Dec. 28, 1943.

Patented Dec. 28, 1943 UNITED STATES PATENT OFFICE Claims.

is a tedious one, and requires a considerable.

amount of time, largely on account of the reaction of the pressure within the system, as it gets stronger, until it practically equalizes the force of the pump. One of the purposes of the present invention is to provide a multiple pump,

of novel construction, which can be used in the usual manner up to the point where the pressure.

reaches. a maximum, and worked on a smaller piston capacity for the rest of the operation. By this means the time required for the operation is greatly'lessened.

In its preferred form the device embraces a triple pump system, with a central. pump or cylinder of relatively large capacity and a pair of side pumps or cylinders in line with the main.

cylinder, of a smaller diameter, and in line with each other, so that the pistons of all three can be operated from one operating lever or bar. For this part of the operation one end of the lever is anchored, so that the pistons of all the pumps work in unison, but as, the pressure increases the anchor bar is disconnected, and the. connection of the lever with the piston rod of.

the central pump serves as a fu1crum,upon which the lever is rocked, giving a force-pump action alternately to one and other of the side cylinders, with a continuation of the lifting operation of the jacks.

The above named, and other features and advantages of the invention will be more particularly pointed out in the following specification, reference being had to the accompanying drawing, in which Fig. 1 is a plan view of a pump system embodying the invention.

Fig. 2 is a longitudinal section on the line 2--2 of Fig. 1.

The reference number 5 indicates a pump casing, in form of a block, centrally of which is a bore l, connected at its ends with a pair of channels 8 and 9, extending lengthwise of the casing, and parallel witheach other. Mounted in the side of the casing is a cylinder 10, communicating with the bore 7 through a passageand provided at its outer end with a screwthreaded plug I2, in which is slidable the rod I3 of a piston or plunger It. At the sides of the bore 7 are bores l5 and it, of smaller diameter, also communicating at their ends with the channels 8 and 9.

Mounted in the cylinder 6 in line with the bore I5 is a cylinder ll, of a diameter corresponding with that of the bore 55, and connected therewith through a passage it. In the end of the cylinder I1 is a screw-threaded plug l9, in which is-slidable a rod 20, on the inner end of which is a piston 2!. At the outer end of the rod 20 is pivoted thereto a link 22, which has a pivotal connection with a hand-lever 23, as at a. The outer end of the rod I3 is'similarly connected with the lever 23 as at b..

A cylinder 24, of similar size and capacity as the cylinder ll, is connectedwith the bore I6 by a passage 25, and at the outer end of said cylinder 24 is a threaded plug 26, having an opening in which is slidable a rod 2?, provided on its in-- ner end with a piston 28. The outer end of the rod 2'! is also provided with a link 29. pivotally connected with the lever 23. The lever is anchored at one end by a bar 3%), one end of which is rockingly connected with a pin 3| supported at the. end ofthe casing 6. The outer end of the;

of the casing are united by a passage 33, normally closed at its upper end by a valve mechanism, as hereinafter set forth. Communicating with the channel 8 is a pair of pipes 35 and-36, each of which connects with one of a pair of hydraulic jacks, not shown herein, but similar to those set forth in said former application;- and each provided with a shut-01f cock, as at 3 By this means the movement of hydraulic mes,

dium through one or both of said pipes may be interrupted. The lower channel is connected;

with a supply tank 39 by means of a pipe 38, pro-- vided with a cut-out valve at til. The tank can be supported at any suitable point about a truck or other device containing pressure apparatus. The tank 39 is closed to the escape of medium in any other direction than through the pipe 38, and the tendency of the action of the pumps is to drive the liquid in the direction of the

pipes

35 and 36, and through the same.

In the lower part of the bore 1 is a threaded valve casing 4|, with an opening 42, normally In a similar manner the bores l5 and [B are L fitted in their lower ends with check-

valves

48 and 49, and in their upper ends with check-valves 50 and 5|. It can be assumed that by the combined action of the pumps a maximum quantity of the hydraulic medium can be forced out through the

pipes

35 and 36 to the jacks or other pressure devices, with a rapid operation thereof.

Up to a certain point'in the operation of the pumps the pressure is increased, due to the increased resistance in the jacks or rams, or whatever may be responding to the operative force, until the pressure is so great that the movement of the pistons in the cylinders practically ceases. When this occurs the rod 30 is disconnected from the end of the lever by swinging the same upwardly, and the operation continued by rocking the lever 23 upon its central pivotal point as a fulcrum. At this time the piston I4 is near the outer end of its movement, and is stationary, forming a substantial support upon which the lever is rocked. This results in an alternating movement of the two smaller pistons, with a continued upward movement of the jacks, or object that is being raised. The amount of pressure exerted against the pistons is multiplied in proportion to the size thereof, so that the smaller pistons continue to operate after the large one in the center is forced to be idle. In-case it is desired to cause a greater elevation at one side of a truck or trailer, or other object, this is accomplished by closing the

pipe

35 or 36 at the other side, causing all of the force to 'be exerted in the desired direction.

At one end of the channel 8 is a plug 52, and at the other end is a valve 54, normally closed by a needle-valve 55, having a threaded part rotatable in a plug 56, and provided with a handle 51 for rotation. When the valve 54 is opened the pressure is permitted to escape through the passage 33, with a gradual return of the hydraulic medium to the supply tank 34, and a consequent gradual return of the jack elements downwardly.

What I claim and desire to secure by Letters Patent is:

1. In a pump for hydraulic systems, a casing provided with a plurality of passages for the, con duct of a volume of hydraulic medium. provided with an intake in one of its sides and one or more outlets at another point, a pair of cylinders of varying diameters mounted on said casin proximity to said cylinders, and connections between said pistons and said handlever adaptable to a joint operation of said pistons or a separate operation of the smaller piston fulcrumed upon the larger piston as a support.

2. In a pump for hydraulic systems, a casing provided with a plurality of passages for the conduct of a volume of hydraulic medium, including a central bore of relatively larger size, and side bores of more limited size, an intake pipe connected with said passages, and one or more outlets for conveying the medium to other mechanisms, a central cylinder of relatively large size communicating with the central bore, and provided with a piston and rod therefor, side cylinders of less diameter than the central cylinder provided with pistons and rods corresponding therewith, a hand-lever operatively connected with said piston-rods, and means for holding one end of said hand-lever as a fulcrum therefor, de-

, tachable to permit the rocking of the lever upon the central piston, as a stationary support.

3. In a device of the class described, a casing and bores therein of varying sizes, provided at one end with intake check-valves and at the other end with out-let check-valves, a sys tem of channels connected with said bores, connected with a hydraulic medium source of supply and having one or more outlets for the discharge of said medium, pump cylinders on said casing communicating with said bores and having pistons corresponding therewith in size, a hand-lever operatively connected with said pistons, an anchor for said hand-lever holding it in position for joint operation of the pistons, and releasable to permit'the rocking of the lever with the larger piston as a supporting base.

4. In a pump for hydraulic systems a casing provided with a plurality of passages for the conduct of a quantity of hydraulic medium, a supply tank for said passages communicating therewith, two or more cylinders on said casing connected with said passages, and of varying capacity, pistons in said cylinders, a hand-lever operatively connected with said pistons, means for compelling a joint action of the pistons, or an independent action of those of less capacity, based on the ones of greater capacity, one or more outlets for the medium for said casing, and a release mechanism permitting the return of the medium to the supply tank.

5. In a pump for hydraulic systems, a casing provided with a system of passages for a hydraulic medium, an inlet for said medium and supply tank connected with said inlet, one or more outlets for said system provided with shut off cocks, a central cylinder of relatively large size mounted on said casing, provided with a piston and rod therefor, and communicating with said passage system, one or more smaller cyl nders mounted on said casing, also communicating with the passage system, and provided with pistons and rods therefor, a hand-lever operatively connected with said rods, and means attachable to said lever to compel the joint operation of said pistons, and releasable therefrom to perm t the action of the smaller pistons with the larger piston serving as a fulcrum support.

HAROLD J. MCGOVERN.