US2687291A

US2687291A - Hydraulic speed responsive pump and motor type governor

Info

Publication number: US2687291A
Application number: US298097A
Authority: US
Inventors: Ifield Richard Joseph
Original assignee: Lucas Industries Ltd
Current assignee: ZF International UK Ltd
Priority date: 1952-07-10
Filing date: 1952-07-10
Publication date: 1954-08-24
Anticipated expiration: 1971-08-24

Description

2,687,291 HYDRAULIC SPEED RESPONSIVE PUMP AND MOTOR TYPE GOVERNOR Filed July 10, 1952 R. J. [FIELD Aug. 24, 1954 2 Sheets-Sheet 1 LzUiZZZ'ZlD JSLJIJZLeZQL R. J. IFIELD 2,687,291

HYDRAULIC SPEED RESPONSIVE PUMP AND MOTOR TYPE GOVERNOR Aug. 24, 1954 2 Sheets-Sheet 2 I Filed July 10, 1952 FIG. lb.

F|G.2b.

FIG.20.

INVENTOR- R. J. IF'ELD ATTORNEY Patented Aug. 24, 1954 HYDRAULIC SPEED RESPONSIVE PUMP AND MOTOR TYPE GOVERNOR Richard Joseph Ifield, Dural, New South Wales, Australia, assignor to Joseph Lucas (Industries) Limited, Birmingham, England Application July 10, 1952, Serial No. 298,097

Claims. 1

This invention relates to speed-responsive governors of the kind adapted to utilise the centrifugal pressure of a rotating liquid. The object of the invention is to enable the desired stability to be obtained in a simple manner.

The invention comprises a governor of the kind aforesaid which consists in part of a rotary member having at least one liquid-flow passage of spiral form, and a displaceable and spring-loaded member responsive to the centrifugal pressure of the liquid.

In particular the invention comprises a governor as above specified having therein a series of intercommunicating spiral passages, the said passages being alternately of opposite hand.

The invention will be described hereinafter with reference to the accompanying drawings, in which:

Figure 1 is a part sectional view diagrammatically illustrating one embodiment of the invention,

Figures 1a and 1b are sectional views taken respectively. along the lines la--|a and lb-lb of Figure 1,

Figure 2 is a view similar to Figure 1 but diagrammatically illustrating another embodiment of the invention, and

Figures 2a and 2b are sectional views taken respectively along the lines 2a2a and 212-211 of Figure 2.

Referring to Figure 1, there is provided a hollow body part a which includes three chambers respectively marked b, c, d, the two chambers b, 0 being in communication with each other by way of a passage e. In the chamber 12 is contained a rotor provided with a driving spindle g. The rotor comprises a pair of discs on one of which is formed a spiral passage 11., the open side of this passage being closed by the other disc. The rotor is supported in the body part a by a bearing for the spindle g, and also by a bearing for a stub spindle extending from the opposite side of the rotor. The stub spindle is made hollow affording a vertical opening g and is in communication at its ends with the compartment d and the central part of the spiral passage in the rotor.

The chambers c, d are separated by a flexible it a liquid-operated servo mechanism, as described in the specification of Letters Patent No. 2,403,371 to R. J. Ifield et al. The servo-mechanism comprises a cylinder 2 which at one end communicates with the delivery passage 3 of the pump. Both ends of the cylinder are in communication with each other by way of a passage 4 containing a restricted orifice 5. In the cylinder is contained a piston 6 loaded by a spring I, and connected by a rod 3 with the angularly adjustable swashplate of the pump. Movement of the piston in one direction results in reduction of the pump output, and movement in the opposite direction is accompanied by increase of the pump output. The end of the cylinder 2 remote from the connection with the passage 3 is connected by a pipe 9 to the seating o of the governor, and the governor valve box 11. is connected by a pipe ill with the pump inlet or a sump.

The mode of action of the governor is as follows:

The chambers 22, c are filled with any convenient liquid. With the rotor in action centrifugal pressure is set up in the spiral passage of the rotor, and this pressure is transmitted through the ambient liquid to the diaphragm. Normally the valve in the valve box is closed, and in this condition the spring I acting on the piston 6 of the servo-mechanism moves the piston in the direction for obtaining maximum output from the pump. When the governor rotor reaches a predetermined speed, the pressure of diaphragm i loaded by a tension spring and in the chamber 11 is contained one part of a lever is loaded by a spring m, this part of the lever being operable by the diaphragm. The other part of the lever extends through a seal into a valve box 12 containing a valve seating o with which c'o-operates a closure member 10 on the lever 10.

In the example shown the governor is arranged to control the outputof a fuel pump for a jet engine, gas turbine or the like, the pump being of the swash plate type having combined with the liquid acting on the diaphragm i displaces the latter and causes it to move the lever k in the direction for opening the associated valve.

Liquid can then pass through the valve along the pipe 9 from the servo-mechanism and the preponderating liquid pressure then acting on the side of the piston 6 remote from the spring 7 moves the piston in the direction forv effecting a corresponding reduction of the pump output.

With fall of speed of the rotor the spring i returns the diaphragm i to its initial position and liquid in the chamber o is displaced to the chamber a and rotor.

By making the spiral passage in the rotor of appropriate length and cross section any desired degree of inherent damping and consequent stability of action of the governor can be obtained during changes of speed in a simple and convenient manner.

' Replenishment of loss of liquid from the chambers b, c of the governor is efiec'ted from the chamber d, this chamber being supplied from any conveniently arranged reservoir H through a pipe Ha.

In the example shown in Figure 2, the hollow body part a is shaped to provide a single chamber 1) for enclosing the rotor J. The rotor is con- -3 structed to form two chambers, one of which is totally enclosed and the other (I3) is open to the chamber 13. The two chambers in the rotor are separated by a flexible diaphragm i, this being loaded by a compression spring in the chamber 13. The rotor comprises a plurality of discs on each of which is formed a spiral passage, the alternate passages being of opposite hand to the others. Also the discs are grouped as shown, and the groups are separated by partitions M. The spindle g carrying the discs is hollow along a portion of its length and comprises two parts in one of which are formed an axial passage and lateral ports it. Also at one end of one of the spindle parts is secured a closed and collapsible capsule 11. For admission of air to the portion of the spindle containing the capsule breathing apertures 18 are provided in the spindle and the adjacent portion oi the body part. Alternatively liquid may be admitted to the last mentioned portion of the spindle from the chamber b.

Starting with the bottom disc shown in the drawing, and assuming the rotor to be in motion, liquid can be displaced outwardly during a change of speed along the associated spiral passage h. This displacement is accompanied by an inward displacement along the next passage b (the spiral of which is of opposite hand to the first). The inner end of the second passage is in communication with the adjacent end of the third passage I1 and its outer end is in communication with the outer end of the fourth passage h (which is similar to the second passage 11. The inner end of the fourth passage communicates with the inner end of the fifth passage (which is similar to the first), the whole forming a series or" passages along which liquid displacements occur alternately in opposite directions. Liquid displaced from the last passage 11 acts on the diaphragm. Avoidance of cavitation in the liquid is effected by the capsule H which can collapse under atmospheric pressure when liquid is drawn from its interior. By an arrangement as above described a restricted channel of any desired length for efiecting the required damping action on the liquid during changes of speed can be accommodated in a com pact form.

Pressure of the liquid on the diaphragm 1' serves to actuate a valve in a similar manner to that described with reference to Figure 1. On the body part a is mounted a valve box a containing a lever is loaded by a spring m and carrying a closure member p which co-operates with a seating o in communication by way of a pipe 9 with the servomechanism or" the pump. The lever 70 is operable by the diaphragm 2' through a push rod 22. The valve box is connected to the inlet side of the pump (or a sump) by way of the pipe Hi. It also communicates with the chamber of the body part a through an orifice 23, the chamber of the body part being filled (when the governor is in use) by liquid derived from the pump. The servomechanism is similar to that of Figure 1, and is controlled in like manner by the action on the diaphragm i by the liquid contained in the rotor.

The use of a governor as above described is not, however, restricted to the control of a fuel supply pump, as they may be used in other ways for controlling the rate or" supply of liquid fuel to an engine in response to the speed of the engine. Thus they may be adapted. to control a fuel throttle or a by-pass in a, fuel supply system. Moreover, the governors may be applied to other uses where it is required to produce a controlling or other eilect in response to speed, such as the actuation of a switch in an electrical system. Further, subordinate details of construction may be varied to suit different requirements.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. A speed-responsive governor of the kind adapted to utilize the centrifugal pressure of a rotating liquid comprising, in combination, a rotary member including at least one liquid-flow passage of spiral form having a plurality of turns to afiord inherent damping and consequent stability of action during changes of speed, and a displaceable and spring-loaded member responsive to the centrifugal pressure of the liquid created by the rotary member.

2. A speed responsive governor of the kind adapted to utilize the centrifugal pressure of a rotating liquid comprising, in combination, a rotary member including a plurality of axially spaced liquid-flow passages of spiral form each having a plurality of turns and the spiral passages being alternately of opposite hand, means affording intercommunication between adjacent inner and outer ends of the spiral passages to constitute a single passage which extends alternately inwardly and outwardly, and a displaceable and spring-loaded member responsive to the centrifugal pressure of the liquid created by the rotary member.

3. A governor according to claim 2, comprising a collapsible capsule located within the rotary member and having its interior in communication with the inner end of the single passage, and means for admitting air to the outside of the capsule.

4. A speed responsive governor of the kind adapted to utilize the centrifugal pressure of a rotary liquid comprising, in combination, a 1'0- tary member formed to provide two chambers separated by a flexible diaphragm, one of said chambers including a plurality of axially spaced liquid-flow passages of spiral form each having a plurality of turns and the spiral passages being alternately of opposite hand, means affording intercommunication between adjacent inner and outer ends of the spiral passages to constitute a single passage which extends alternately inwardly and outwardly, and spring loading means for the flexible diapln'agm which thereby constitutes means responsive to the centrifugal pressure of the liquid created by the rotary member.

5. A speed responsive governor according to claim in which the spiral passages are formed on one side of discs which are grouped in pairs with the passages lying adjacent but separated by partitions.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,045,647 Wallace Nov, 26, 1912 1,586,160 Mauron et al. May 25, 1926 2,429,995 Watson et al. Oct. 14, 1947 2,527,353 Christian Oct. 24, 1950 FOREIGN PATENTS Number Country Date 1,324 Great Britain May 26, 1863 340,152 Great Britain Dec. 24, 1930