US3635600A

US3635600A - Device for feeding pressurized fluid

Info

Publication number: US3635600A
Application number: US14067A
Authority: US
Inventors: Pierre A Praddaude
Original assignee: Poclain SA
Current assignee: Poclain SA
Priority date: 1969-03-07
Filing date: 1970-02-25
Publication date: 1972-01-18
Anticipated expiration: 1989-01-18
Also published as: ES377160A1; DE2010902A1; FR2038454A5; GB1266808A

Abstract

This invention relates to a device for feeding pressurized fluid to at least two supply circuits by two groups of variable discharge pumps, the first group of pumps comprising two distinct delivery conduits and a first power regulator being coupled with the member for controlling the discharges of said first group of pumps, while a second power regulator is coupled with the member for controlling the discharge of the second group of pumps, wherein the first power regulator is of the pressure simmation type, the second group of pumps comprises a single delivery conduit and the first delivery conduit of the first group of pumps and the single delivery conduit of the second group of pumps are connected to the first supply circuit, while the second delivery conduit of the first group of pumps is connected to the second supply circuit.

Description

[451 Jan. 18, 1972 [54] DEVICE FOR FEEDING PRESSURIZED FLUID [72] Inventor: Pierre A. Praddaude, Crepy-en-Valois,

France [73) Assignee: Societe Anonyme Poclain, Le Plessis-Belleville, France [22] Filed: Feb. 25, 1970 [2i] Appl.No.: 14,067

[30] Foreign Application Priority Data Mar. 7, 1969 France ..69065S9 [56] References Cited UNITED STATES PATENTS Archer ..4 l 7/62 3,496,960 2/l970 Hughes ..41 7162 Primary Examiner-Robert M. Walker Anomey.lohn Lezdey S 7] ABSTRACT This invention relates to a device for feeding pressurized fluid to at least two supply circuits by two groups of variable discharge pumps, the first group of pumps comprising two distinct delivery conduits and a first power regulator being coupled with the member for controlling the discharges of said first group of pumps, while a second power regulator is coupled with the member for controlling the discharge of the second group of pumps, wherein the first power regulator is of the pressure simmation type, the second group of pumps comprises a single delivery conduit and the first delivery conduit of the first group of pumps and the single delivery conduit of the second group of pumps are connected to the first supply circuit, while the second delivery conduit of the first group of pumps is connected to the second supply circuit.

5 Claims, 3 Drawing Figures PATENTEDmvsmn 3 635 600 PIERRE A PRAbbAUbE lrwenlw Z 2 Me DEVICE FOR FEEDING PRESSURIZED FLUID The present invention relates to a device for feeding pressurized fluid.

As is known, the use of pressurized fluids means that a supply circuit is fed by a pump or a group of pumps.

One means of regulating the operation consists in selecting a variable discharge pump and in checking the fluid discharge as a function of the delivery pressure by a regulation member, hereinafter designated simply as "regulator. In order to maintain the power called upon by the supply circuit below a limiting power, regulation is advantageously ensured by a con stant power regulator.

If it is now desired to feed two supply circuits, one pump or a group of pumps with two discharges may, as is well known, be selected. A constant power regulator limits the total power called upon by the two supply circuits and is for example of the pressure summation type.

However, all these devices have the disadvantage of having to choose high-power pumps in order to deal with the highest demands of power imaginable which are occasionally required during normal operation of the supply circuits. Now, this highest demand is sometimes, even very often, exceptional, and involves a choice of equipment having excessive powers for almost the whole duration of their operation.

The applicants have had the idea of providing, in the case of at least two supply circuits, that the power not demanded by one of the circuits be directed to the second circuit for feeding same. To this end, they have designed an original supply device which specifically forms the object of the present application.

The invention therefore has for its object a device for feeding pressurized fluid to at least two supply circuits by two groups of variable discharge pumps, the first group of pumps comprising two distinct delivery conduits and a first power regulator being coupled with the member controlling the discharge of said first group of pumps, while a second power regulator is coupled with the member controlling the discharge of the second group of pumps.

The first power regulator is of the pressure summation type and the second group of pumps comprises a single delivery conduit. The first delivery conduit of the first group of pumps and the single delivery conduit of the second group of pumps are connected to the first supply circuit, while the second delivery conduit of the first group of pumps is connected to the second supply circuit.

The first delivery conduit of the first group of pumps and the single delivery conduit of the second group of pumps are advantageously connected to the first supply circuit by a single connection.

Moreover, a selector may be arranged on the first delivery conduit of the first group of pumps in order to ensure at least the communications of the first delivery conduit of the first group of pumps selectively with the first supply circuit, and with a third supply circuit.

Finally, the first group of pumps is constituted, for example, by a single pump with two discharges, or even by two separate pumps.

In order that the invention be more readily understood, and to explain various secondary features and their advantages, an embodiment thereof will now be described by way of example with reference to the accompanying drawings, in which FIG. I is a view, with part section, of a device according to the invention;

FIGS. 2 and 3 are schematic partial views of the device shown in FIG. 1.

Referring now to the drawings, FIG. I shows three variable discharge pumps l, 2 and 3. These pumps have their suction members connected for example to a hydraulic oil tank; they are not shown in the drawing, as this detail is known per se.

Two of these pumps I and 2 are grouped into an integral assembly 4 which may moreover have an equivalent in a single pump which would be constituted by joining the pumps I and 2 in a single casing 5. In the case of the separated pumps 1 and 2 illustrated, the members 6 and 7 for controlling the discharges are connected by an articulated tie connection 8.

The

pumps

1, 2 and 3 are moreover provided with their

respective delivery conduits

9, 10 and I1. Pipes I2, 13 and 14 are branched onto

conduits

9, 10 and 11, for example by welding, and connect said conduits l2 and 13 to a power regulator 15 with pressure summation, and conduit I4 to a power regulatdr l6.

Itrill be recalled that a power regulator such as 16 is a member which, as a function of the pressure of the fiuid in the delivery conduit 11 transmitted through the pipe 14, acts by its rod l7 on the member 18 for controlling the discharge of the pump 3. This regulator limits the power delivered to the supply circuit to a predetermined value. In a power regulator such as 15, of the pressure summation type, it is the sum of the actions of the pressures prevailing in the

delivery conduits

9 and 10, said pressures being transmitted by the fluids in the

pipes

12 and 13, which acts on the rod 19 of the regulator 15, which in turn acts on the articulated tie connection 8, thus on the members 6 and 7 controlling the discharges of pumps 1 and 2.

In other words, the regulator 15 is the intermediary element which makes it possible to modify the position of control members 6 and 7 of the pumps in such a way that the absorbed power remains constant. It is understood that, everything being equal, an increase in the delivery pressure of one of the pumps corresponds to a decrease in the flow and vice versa. Thus, when the pressure rises in one of the delivery conduits 9 or 10, the action on regulator 15 contributes to the pushing back of rod 19 and therefore to the movement of control members 6 and 7 of the variable flow pumps 1 and 2.

Regulator l6 acts in the same manner as regulator 15 but only with regards to the control of the pump 3.

Moreover, the delivery conduit 9 is connected to a supply circuit, of which the inlet conduit 20 has been shown by a thimble 2I for example. Similarly, the conduit 10 is connected to one of the channels 220 of a three-way selector 22, and extends so as to connect a second channel 22b of the selector 22 to a connecting thimble 23 having three apertures. On the third channel 220 of the selector 22 is connected a third circuit shown by its inlet conduit 24. If the supply circuit, to which conduit 20 belongs, is called the second circuit, the first circuit, shown by its inlet conduit 25, is connected to the thimble 23. Finally, the delivery conduit 11 of the pump 3 is connected to the final aperture of the thimble 23.

FIGS. 2 and 3 schematically show two positions of the three-way selector 22. In FIG. 2, the selector communicates the two parts of conduit 10, isolating conduit 24 from the third supply circuit at 22c. In FIG. 3, on the contrary, the selector communicates the first part of the conduit 10 with conduit 24, and isolates the second part of conduit 10 from the first part of the same conduit substantially at 2212.

The advantages of the invention will be more apparent after reading the description of the operation.

The case where selector 22 is arranged as shown in FIG. 2 will firstly be examined. This configuration comes back to feeding the two supply circuits corresponding to the inlet conduits 20 and 28 by the groups of pumps, the third circuit (conduit 24) being isolated and not fed- The power delivered through pump 1 is absorbed by the second circuit (conduit 20), while the powers delivered by the

pumps

2 and 3 are absorbed by the first circuit (conduit 28), conduits I0 and 11, connected to the thimble 23, being in communication with conduit 25. The total power of the two groups of pumps remains of course, limited to the sum of the two limiting values defined by the regulators l5 and 1.

The use of such a device is specified in the following example in which the power of each of

pumps

1, 2 and 3 is equal to 60 horsepower (hp. In this configuration, the first supply circuit (conduit 25) may call upon a power of I hp., the second circuit (conduit 20) obviously consuming nothing. The first supply circuit (conduit 25), permanently fed by the pump 3, is thus complementarily fed by pump 2 with a discharge and at a pressure which correspond to the total power of pumps 1 and 2. With a conventional separate configuration with two supply circuits, each fed by a pump, or by a group of pumps, if it was desired to continue to have the possibility of calling upon 60 and I80 hp. by the two supply circuits, it would in fact have been necessary to have separate pumps with powers of 60 and 180 hp. The new arrangement enables pumps of lower power to be used for the same service. 5.

Furthermore, when the selector 22 is arranged as in FIG. 3, it is possible to supply three circuits, this obviously not being possible when there are only two separate pumps without a special device for distributing the discharge towards the supply circuits. In the configuration of FIG. 3, the first supply circuit (conduit 25) is fed solely by pump 3, the power supplied by said pump 3 being limited by the regulator 16. The second circuit (conduit and the third circuit (conduit 24) are fed respectively by pumps l and 2 in a certain discharge ratio, adjustable by defining the regulator 15, the total power supplied by pumps 1 and 2 being limited by the regulator 15. There are therefore three independent supply circuits which it is possible to feed through the three

pumps

1, 2 and 3.

The advantage of the feed device according to the invention is clear, in that with low-power pumps, supply circuits consuming a high-power are fed, or with the same arrangement, three separate circuits are fed.

It will also be understood that the three-way selector 22 in the embodiment shown, may or may not be installed, and the operation corresponding to the configuration of FIG. 2 is obtained, or there may be more than three channels, and a fourth channel, for example, may direct the delivered fluid through pump 2 through the conduit 10 towards the conduit 20, or towards another supply. This latter configuration is naturally in accordance with the invention. Finally, if the selector 22,

which has been shown, is of the type with a dome casing, it is understood that it has equivalents for example in a slide valve distributor.

1 claim:

1. A fluid control system for feeding pressurized fluid to at least two supply circuits comprising a first group of variable discharge pumps having two distinct delivery conduits; a first power regulator means with pressure summation; means for controlling the discharges of said first group of pumps coupled with said first power regulator; a second group of variable discharge pumps having a delivery conduit; a second power regulator means and means for controlling the discharge of said second group of pumps coupled with said second power regulator means; and the delivery conduit of said second group of pumps and the first delivery conduit of said first group of pumps are connected to the first supply circuit and the second delivery conduit of said first group of pumps is connected to the second supply circuit.

2. The system of claim 1, wherein said first delivery conduit of said first group of pumps and the delivery conduit of said second group of pumps are connected to the first supply circuit by a single connection.

3. The system of claim 1 including selector means arranged on the first delivery conduit of said first group of pumps whereby the first delivery conduit of said first group of pumps is in selective communication with the first supply circuit and a third supply circuit.

4. The system of claim I, wherein said second group of pumps is a single pump with two discharges.

5. The system of claim 1, wherein said first group of pumps is two separate pumps.

s t s s a

Claims

4. The system of claim 1, wherein said second group of pumps is a single pump with two discharges.