US3774411A

US3774411A - Drive couplings

Info

Publication number: US3774411A
Application number: US00183056A
Authority: US
Inventors: R Phillips; Z Miracki
Original assignee: Simms Group Research and Development Ltd
Current assignee: Simms Group Research and Development Ltd
Priority date: 1970-09-30
Filing date: 1971-09-23
Publication date: 1973-11-27
Anticipated expiration: 1990-11-27
Also published as: JPS5023456B1; FR2108744A5; GB1357534A; ES199718Y; ES199718U

Abstract

A coupling for use in a fuel injection pump comprises a pair of members and a fluid pressure operable piston acting intermediate the members. The supply of fluid under pressure of the pistons is controlled by a valve member which is disposed to be influenced by centrifugal force. The motion of the valve member under the action of centrifugal force is resisted by a leaf spring and the force exerted by the leaf spring is adjustable by means of a roller which co-operates with a surface on a member in such a manner that as the centrifugal force increases and the piston moves to effect relative movement of the members, the roller will move to increase the force exerted on the valve element thereby to establish an equilibrium.

Description

I United States Patent 1191 [111 3,774,41 1

Phillips et al. Nov. 27, 1973 DRIVE COUPLINGS 3,062,027 11 1962 Pigeroulet 64/25 3,258,937 7/1966 K t l. 64 25 75 Inventors: Ronald Pllllllps, 1901 11611; Zdznslav 2,950,610 8/1960 n Stamsh" Mlraekl, Fmehley, 3,603,112 9 1971 S0l3.... 64/25 London, both of England [73] Assignee: Simms Group Research & 1 P'imary Examinerchal'les y Development Limited, mndon Assistant En land Attorney-Holman and Stern 22 Pl d: Se 1. 23 1971 1 p 57 ABSTRACT [21] Appl 183056 A coupling for use in a fuel injection pump comprises a pair of members and a fluid pressure operable piston [30] Foreign A li ation Pri it D t acting intermediate the members. The supply of fluid Sept. 30 1970 Great Britain 46 409 70 Pressure of the Pistorls is controlled by a valve member which is disposed to be influenced by centrif- 52 us. Cl. 64/25, 123/139 AP feree- The ef the valve member under the 51 lm. Cl. Fl6d aetie" ef centrifuge feree is resisted by a leaf Spring [58] Field of Search 64/25 26- end the force exerted by the leaf spring is adjustable 123/139 by means of a roller which co-operates with a surface on a member in such a manner that as the centrifugal [56] References Cited force increases and the piston moves to effect relative movement of the members, the roller will move to in- UNITED T T PATENTS crease the force exerted on the valve element thereby 31%? s i to establish an equilibrium, 9 1 Z aga 6 Claims, 6 Drawing Figures 3,004,410 10/1961 Pierce 64/25 El o PATENTEDHUYZT E975 3774.411 sum 2 a? 4 FIGS.

INVENTOR ATTORNEYS DRIVE COUPLINGS This invention relates to drive couplings for use with liquid fuel injection pumping apparatus having a drive shaft, the coupling comprising in combination, a pair of members one of which is connected to the drive shaft and the other of which is connected in use, to a rotary drive element, means coupling the members to transmit rotary motion therebetween and means for varying the relative angular position of said members.

The object of the invention is to provide such a coupling in a simple and convenient form;

According to the invention a coupling of the kind specified comprises a bore defined in one of the members, a fluid pressure operable piston mounted in said bore and arranged when subjected to fluid pressure to effect relative angular movement of the members, resilient means acting between said members and against the action of which the members are moved angularly by the piston, valve means including a valve element which is movable under. the action of centrifugal force for controlling the admission of fluid under pressure to said bore, spring means acting on said valve element to oppose the action of centrifugal force and means responsive to the relative angular position of the members'for varying the force exerted by the spring means on the valve element.

One example of a drive coupling in accordance with the invention will now be described with reference to the accompanying drawings in which:

FIG. 1 is a section on the line AA of FIG. 5,

FIG. 2 is a section on the line B-B of FIG. 1,

FIG. 3 is a section on the line D-D of FIG. 1,

FIG.,4 isasection on the line C--C of FIG. ll,

FIG. 5 isa side elevation of the coupling with part of thecover removed to show the interior of the coupling,

and

FIG. 6 is a partial view similar to FIG. 1 showing an alternative position of the parts of the coupling.

Referring to FIG. 2 the coupling comprises a pair of members 10, 11 the member 11 being joumalled about a cylindrical extension formed integrally with the member 10. The member 10 is provided with a tapered bore 1 12 in which is engaged a drive shaft 13 forming part of a liquid fuel pumping apparatus, the housing of which is seen at 14. The member 10 is accommodated within a cup shaped housing 15 the open end of which extends around the member 11. Moreover, located in the member II is a peripheral groove in which is accommodated a fluid seal 16.

Turning now to FIG. 11 it will be seen that the member 10 is cut away at substantially diametrically opposite points to accommodate projections Illa formed on the member 11. The member 10 defines a pair of blind bores 17 which extend in opposite directions and located within the bore 17 are a pair of pistons 18 respecmunicate with a drain passage 26 a supply passage 27 respectively. The supply passage 27 communicates with a passage 28 formed within the pump casing 14 and this communicates with a source of fluid under pressure.

The extent of inward movement of the valve element 23 is limited by a pin 29 and at its outer end the valve element bears against a spring means in the form of a leaf spring 30. At one end the spring 30 is engaged around a post 31 connected to the member 10 and adjacent its other end the spring 30 bears against a roller 32 carried upon a forked arm 33 which is pivotally connected to the adjacent extension Ii la of the member 1 1. In addition, the roller 32 bears upon a shaped surface formed on an abutment member 34 which is carried by the member 10. In addition, resilient means in the form of a pair of springs 35 are provided to urge the members l0 and 11 relative to each other against the action of the force developed by the pistons 18.

In operation, the coupling rotates in the anticlockwise direction as seen in FIG. 1, the member 11 being driven by the associated engine so that the drive is transmitted through and the spherical members 19 and the pistons 18 to the member 10. The valve element 24 being disposed in a radial plane, is subjected to centrifugal force and as the valve element moves outwardly against the action of the spring 30 the port 21 will be uncovered to the groove 25 so that fluid under pressure is admitted to the cylinders 17. The effect of this is to urge the pistons outwardly from their cylinders and relative angular movement will occur between the members 10 and Ill. As such angular movement takes place the forked member 33 will move relative to the member 34 and the roller 32 will be moved inwardly due to the-action of the shaped surface of the member 34. The effect of this inward movement of the roller is to slightly shorten the effective length of the spring 30 but also to bow the spring so that it exerts an increased force on the valve element. A point is reached at which an equilibrium is established and the port 21 is closed. Once the port 21 is closed as hydraulic lock exists in the ends of the cylinders and no further movement of the pistons takes place. If the speed increases further the process is repeated and if the speed decreases the valve element 23 moves in the opposite direction under the action of the leaf spring until the port 21 is uncovered to the groove 24. When this occurs fluid escapes from the cylinders 17 and a fresh equilibrium is established.

As is shown in FIG. 3 the forked member 33 at its end remote from the roller 32, is pivotally mounted about a pin 36 and this pin is eccentrically mounted upon an angularly adjustable member 37. In this manner the initial position of the roller 32 upon the shaped surface of the member 34', can be adjusted and in this manner the response characteristic can be adjusted.

We claim:

1. A drive coupling for use with liquid fuel injection pumping apparatus having a drive shaft, the coupling comprising in combination, a pair of members one of which is connected in use, to a rotary drive element, a bore defined in one of the members, a fluid pressure operable piston mounted in said bore and arranged when subjected to fluid pressure to effect relative angular movement of the members, resilient means acting between said members and against the action of which the members are moved angularly by the piston, valve means including a valve element which is movable under the action of centrifugal force for controlling the admission of fluid under pressure to said bore, spring means acting on said valve element to oppose the action of centrifugal force and means responsive to the relative angular position of the members for varying the force exerted by the spring means on the valve element.

2. A coupling as claimed in claim 1 in which said spring means comprises a leaf spring, said valve element contacting the leaf spring intermediate the ends thereof.

3. A coupling as claimed in claim 2 in which one end of the leaf spring is secured to one of the members, and the other end of the leaf spring bears against a roller the position of which varies as a result of relative angular movement between the members.

4. A coupling as claimed in claim 3 in which said roller is mounted on an arm carried by the other of said members.

5. A coupling as claimed in claim 4 including an abutment member carried by said one member said abutment member defining a shaped surface between which and the leaf spring is located the roller, said surface being shaped so that as the piston moves under the action of increasing fluid pressure to effect relative movement of the members, the roller will move on the surface to increase the force applied by the spring to the valve element.

6. A coupling as claimed in claim 5 including means for adjusting the initial position of the roller on said surface.