US2142275A - Fluid pump - Google Patents

Description

Jan. 3, 1939. C. J, LANE 2,142,275

FLUID PUMP I Filed Aug. 24, 1937 Patented Jan. 3, 1939 UNITED STATES PATENT -oFFicE FLUID PUMP Application August Z4,

3 Claims.

This invention relates to a fluid pump and more particularly to a variable volume pump.

Ordinarily, fluid pumps are of the constant volume type, that is, they move a constant volume of fluid at each revolution of the driving shaft. If such a pump be used to operate a hydraulic device that is operated intermittently, the pump will build up an excessive pressure during the time the hydraulic device is not in operation, which must be taken care of by a relief valve or a similar device. It will also be apparent that throughout the time the hydraulic device is not used the pump is performing useless work.

One of the objects of the present invention is to provide a pump in which the volume of fluid moved at each revolution of the shaft is variable. Such a pump may have its volume varied manually in accordance with the output requirements and it also may be so connected with the pump conduits as to be automatically controlled.

Another object of the invention is to provide a variable volume pump in which the capacity of the pump is varied in accordance with outlet pressure.

Another object of the invention is to provide a pump of the eccentric type in which the eccentricity is variable.

Another object of the invention is to provide a variable volume pump in which the volume output of the pump is varied in accordance with the output requirements by decreasing the volume Output as the outlet pressure increases.

Another object of the invention is to provide a variable volume pump in which the pumpis not required to operate under a back pressure during the time there is no output.

Other objects and features of the invention will be apparent from the following description and accompanying drawing, in which:

Fig. 1 is an end elevation of the improved Pump;

Fig. 2 is a sectional view of the pump;

Fig. 3 is a sectional view taken on line 3-3 of Fig. 2 showing the pump in its zero or nonpumping position; and

Fig. 4 is a sectional view on a slightly smaller scale showing the pump in its maximum pumping position.

Referring to the drawing, the pump comprises an outer housing I, a rotor 2, and an inner housing 3 which is movable from the concentric position shown in Fig. 3 to the eccentric position shown in Fig. 4. Rotor 2 is provided with slidable vanes 6 which bear on the interior of the cylindrical housing 3 and transfer uid from inlet 1937, Serial No. 160,694

port l to the outlet port 8 formed in plate 9. The rotor is mounted in the outer housing by bearings II and I2 and is provided with an external driving connection I4 by which the pump, may be driven from any suitable power source (not shown).

The outer housing is formed of three portions which are held in assembled relation by bolts I5. The housing portion I1 contains the inlet I8 through which the uid enters the pump, the

inner portion houses the rotor 2 and inner housing 3, and the outer portion provides the outlet I9 within which is the check valve 2| held on its seat by spring 22. Plates 9 and l0, which are assembled between the .housing portions, serve as the end walls for the pump space dened between the rotor 2 and inner housing 3, and also act as guides for the inner housing 3 which is pivotally mounted on hollow pin 25.

The inner housing is provided with a yoke 21 within which is an eccentric 29, secured to shaft 29, upon which is a lever 30 that may serve either as a manual control or as an indicator. The yoke 21 is also in contact with spring pressed plunger 3| on one side and piston 32 on the other side. The outer end of piston 32 is exposed to the outlet pressure of the pump by means of pipe 33 and conduit 34 which terminates within outlet I9 beyond the check valve 2 I. 'I'he inner housing is normally rocked counter-clockwise to the full eccentric position shown in Fig. 4 by spring pressed plunger 3l, but will be rocked to the concentric position shown in Fig. 3 when the outlet pressure is suiiiciently high to force piston 32 toward the right against the force of the plunger 3l.

In the operation of the pump with no restriction on the outlet the inner housing will assume the position shown in Fig. 4. Movement of rotor 2 will draw iiuid from any suitable source of supply through inlet I8, hollow pin 25, and openings 26, into space 3l between the outer housing I and the inner movable housing 3. From space 31 the fluid will be drawn through opening l into the eccentric space 38 and forced out of port 8, passage M, and past check valve 2I to the outlet I9. The inner housing will remain in the position shown in Fig. 4 only so long as the ow through outlet I9 is unrestricted. 1f they pump be called upon to operate a device (not shown) the pressure within outlet I9 will rise and be transmitted through conduit 34 and pipe 33 to chamber 42. The pressure in the chamber will force piston 32 toward the right and rock inner housing 3 clockwise, thereby reducing the eccentricity and the output of the pump. By a proper adjustment oi.'

spring 43 the pump will have suiilcient pumping action for operating the devices but will reach the zero or non-pumping position when the flow of iluid is stopped. Adjustment of the spring is accomplished by removing cap 48, loosening lock nut 49 and moving threaded member 5I to the desired position. After the desired spring pressure has been obtained, the lock nut 49 is securely tightened and the cap 48 is replaced. The maximum pumping position of the inner housing 3 is preferably limited by the outer housing rather than by th rotor and in the illustrated embodiment the movement of the housing is limited by plug 52 which is adjustably threaded into the outer housing and adapted to be secured in the desired position by lock nut 53.

The concentric or non-pumping position is shown in Fig. 3 and it will be noted that the pressure within outlet I9 cannot be transmitted to the pump because of check valve 2|, therefore it is possible for the rotor 3 to rotate idly within the housing without maintaining the pressure necessary to keep the housing 3 in the concentric or zero position. If the pressure be relieved by using some of the fluid, the pressure will be reduced and piston 32 will move toward the left. Such movement will restore the eccentricity and suilicient iluid will be pumped past the check valve 2| to compensate for that which was used. 'I'he position of lever 30 will indicate the eccentricity of the pump and the extent of the pumping action, and it will be apparent that the lever may be manually operated to control the lpump if it be so desired.

While a preferred embodiment of the invention has been illustrated and described, it is understood that the showing and description are only illustrative and that the invention is not regarded as limited to the illustrated embodiment or otherwise except by the terms of the following claims.

What is claimed is:

1. In a fluid pump, an outer housing having fluid intake and outlet ports and passages therein, a vaned rotor mounted therein, an inner housing cooperating with the rotor to cause pumping action and having a pivotal mounting in the outer housing radially displaced from the axis of the rotor `and being in spaced relation with the outer housing, saidinner housing having a uid intake port providing communication between the interior of said inner housing and the space between said housings, and means for controlling movement of the inner housing about the pivotal mounting to vary thepump output, said pivotal mounting comprising a hollow pin having both ends mounted in the outer housing and having an opening in its periphery communicating with the space between the inner and outer housings and having an end opening communicating with the uid intake port of the outer housing of the Pumll 2. In a uid pump, a main housing having inlet and outlet passages, a vaned rotor journaled therein, an inner housing having a cylindrical portion cooperating with the rotor to cause pumping action, said inner housing having a pivotal mounting on the main housing axially displaced from the rotor axis whereby the eccentric relation between the rotor and the inner housing may be varied,` spring means urging the inner housing to an eccentric position, a iluid pressure operated piston having uid connection with said outlet passage for moving the inner housing to a concentric position, and a stop adjustable from .the exterior of the pump adapted to contact the piston and limit the extent of its movement whereby the piston in turn limits the movement of the inner housing.

3. In a pump of the eccentric vane type, a main housing comprising two outer portions and a center portion, a plate interposed between each side of the center portion and its respective outer portion, one of said outer housing portions having a pump intake therein,'a hollow pin having a bearing in each of the outer portions and extending through the center portion and both plates, an inner housing rotatably mounted on the pin between said plates in spaced relation with the outer housing, a vaned rotor journaled in the main housing and coacting with the inner housing to cause the pumping action, the axis of the rotor and the axis of the hollow pin being displaced whereby movement of the inner housing varies the eccentricity between the inner housing and the rotor, said hollow pin having a peripheral opening in communication with the space between the housings and an end opening in communication with the pump intake, said inner housing having an inlet opening communieating with the space between the housings and having an outlet opening through one of said plates, and means for rotating the inner housing about the hollow pin to vary the pump output.

CLIFFORD J. LANE.

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