GB1592355A

GB1592355A - Mounting device

Info

Publication number: GB1592355A
Application number: GB48268/76A
Authority: GB
Original assignee: Lucas Industries Ltd
Current assignee: ZF International UK Ltd
Priority date: 1976-11-19
Filing date: 1976-11-19
Publication date: 1981-07-08
Also published as: FR2371582A1; FR2371582B1

Description

(54) MOUNTING DEVICE (71) We, LUCAS INDUSTRIES LIMITED, a British Company, of Great King Street, Birmingham, B19 2XF, England, do hereby declare the invention for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - This invention relates to an arrangement for mounting a fuel pump on an internal combustion engine, particularly though not exclusively on a compression ignition engine.

According to the present invention there is provided an arrangement for mounting a fuel pump on an internal combustion engine, comprising a first member adapted to be secured to the engine, a second member secured to the pump, and clamping means clamping together the first and second members, the clamping means being arranged when loosened to permit relative rotation between the members and when tightened to prevent such relative rotation, the clamping means including a pair of mutually engaged screwthreaded elements carried by one of the members, one screwthreaded element having a gear form thereon which meshes with a complementary gear form on the other of the members such that rotation of said one element relative to said one of the members when the clamping means is loosened causes relative rotation between the first and second members in use, the screwthreaded elements being arranged to tighten and loosen the clamping means when relative rotation is effected therebetween in use.

Preferably, the clamping means also includes a split clamping ring which extends around the peripheries of the first and second members, and relative rotation between the screwthreaded elements in use causes free ends of the clamping ring to move towards and away from each other thereby tightening and loosening the clamping ring respectively.

Desirably, - the clamping ring is secured against rotation relative to said one of the members and the screwthreaded elements are mounted on the free ends of the clamping ring.

Most desirably, the clamping ring is secured against rotation relative to said one of the members by means of an interengaging projection and recess arrangement.

Conveniently, the clamping ring has a channel in its inner periphery which receives the peripheries of the first and second members. Most conveniently, side walls of the channel and surfaces of the first and second members with which the side wall engage are conically tapered.

Advangtageously, the clamping ring is formed in two parts which are pivotally inter-connected, relative pivotal movement between said parts causing the free ends of the clamping ring to move towards and away from each other.

It is preferred that the gear form on said one screw-threaded element is a worm gear, and the complementary gear on said other of the members is an arcuate rack. Preferably also, the pair of screwthreaded elements are constituted by a nut and a bolt ssnd the gear form is provided on the bolt. Most preferably, the gear form is a worm gear constituted by part of the screwthreading on the bolt.

An embodiment of the present invention will now be described by way of example, with reference to the accompanying drawings, in which: - Figure 1 is a lateral section through a mounting arrangement according to the present invention; Figure 2 is a sectional view taken along the fine A-A in Figure 1; and Figure 3 is a view in the direction of arrow B in Figure 1.

Referring to the drawings, the mounting arrangement shown therein is for mounting a fuel. pump on a compression ignition engine, a drive shaft of the pump being coupled to an engine-driven shaft for rotation therewith so that the pump is operated by rotation of the engine-driven shaft. The mounting arrangement comprises generally an end plate 10 which is secured to the engine (not shown), a flanged member 11 which forms part of the pump (the remainder of the pump not being illustrated), and clamping means including a clamping ring 12 holding the plate 10 and member 11 in mutual abutment.

The plate 10 has a central aperture 13 therein, through which the aforementioned engine-driven shaft (not illustrated) passes, and three further apertures 14 equiangularly disposed about aperture 13. The apertures 14 receive respective bolts (not shown) by which the plate 10 is secured to the engine. The clamping ring 12 is fixed relative to the plate 10 by means of a keying plate 15 (see Figlure 3) which is secured to the plate 10, a projection on the plate 15 engages in a recess 16 in the clamping ring 12. The plate 10 is circular and a peripheral surface 17 thereof which is engaged by the clamping ring 12 is conically tapered.

The member 11 includes an annular flange 18, a peripheral surface 19 of which is also conicaly tapered and is engaged by the clamping ring 12. The flange 18 has three arcuate apertures 20 therein which are aligned with the apertures 14 in the plate 10. Heads of the bolts received in the apertures 14, or alternatively nuts engaged with those bolts, are disposed in the apertures 20, the arcuate form of the apertures 20 enabling the member 11 to be rotated relative to the plate 10 without removing the bolts.

The clamping ring 12 extends around the periphery of the plate 10 and the member 11, and has a channel 21 in its inner periphery which receives said peripheries. Side walls of the channel 21 which engage the surfaces 17 and 19 are conically tapered. The clamping ring 12 in fact comprises a pair of arcuate parts 22 which are pivotally interconnected. The pivotal interconnection is effected by means of a pair of spaced bushes 23 on an end of one of the parts 22, a single bush 24 on an end of the other of the parts 22, which is accommodated between the bushes 23, and a pivot pin 25 passing through all three bushes 23, 23. Pivotal movement of the parts 22 causes the free ends thereof to move towards and away from each other.

The free end of each part 22 is provided with an integral collar 26 having an aperture 27 extending therethrough (see Figure 2) the enagement being such that the apertures 27 are mutually aligned when the free ends of the parts 22 are in juxtaposition. The apertures 27 receive the shank of a bolt 28, the head of the bolt 28 being engaged with an end of one of the collars 26, so that the bolt .28 is held axially captive thereby. A nut is in screwthreaded engagement with the bolt shank, and engages an end of the other collar 26 through the intermediary of a spring washer 30.

The bolt 28 and the nut 29 form part of the afore mentioned clamping means, it will be manifest -that rotation of the nut 29 relative to the bolt 28 will cause the free ends of the parts 22 to move towards each other, thereby tightening the clamping ring 12. The bolt 28 is disposed tangentially with respect to the radially outer periphery of the flange 18, and part of the screw thread on the bolt shank constitutes a worm gear and meshes with an arcuate rack 31 formed in said outer periphery of the flange 18. Teeth of the rack 31 are produced by a hobbing operation.

In use, the pump is secured against rotation relative to the engine by rotating the nut 29 relative to the bolt 28 so as to tighten. the grip of the clamping ring 12 on the plate 10 and the member 11. However, the pump can be rotated relative to the engine so as to advance or retard the timing of the injection of fuel into the engine, by the pump in the following manner. First, the clamping ring 12 is loosened by rotating the nut 29 relative to the bolt 28. The bolt 28 is then rotated, and the worm-gear constituted by the screw threading thereon acts on the arcuate rack 31 so as to rotate the member 11 relative to the plate 10. It will be manifest that a known rotation of the bolt 28 will cause a known rotation of the member 11 relative to the plate 10, and therefore a known rotation of the pump relative to the engine.

Consequently, the injection timing can be controlled accurately, the bolt 28 being rotated in one direction to advance the timing and in the other direction to retard the timing. When the pump has been rotated by the desired amount, the bolt 28 is held stationary and the nut 29 is rotated to retighten the clamping ring 12.

WHAT WE CLAIM IS: 1. An arrangement for mounting a fuel pump on an internal combustion engine comprising a first member adapted to be secured to the engine, a second member secured to the pump, and clamping means clamping together the first and second members, the clamping means being arranged -when loosened to permit relative rotation between the members and when tightened to prevent such relative rotation, the clamping means including a pair of mutually engaged screwthreaded elements carried by one of the members, one screwthreaded element having a gear form thereon which meshes with a complementary gear form on the other of the members such that rotation of said one element relative to said one of the members when the clamping means is loosened causes relative rotation between the first and

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. engine (not shown), a flanged member 11 which forms part of the pump (the remainder of the pump not being illustrated), and clamping means including a clamping ring 12 holding the plate 10 and member 11 in mutual abutment. The plate 10 has a central aperture 13 therein, through which the aforementioned engine-driven shaft (not illustrated) passes, and three further apertures 14 equiangularly disposed about aperture 13. The apertures 14 receive respective bolts (not shown) by which the plate 10 is secured to the engine. The clamping ring 12 is fixed relative to the plate 10 by means of a keying plate 15 (see Figlure 3) which is secured to the plate 10, a projection on the plate 15 engages in a recess 16 in the clamping ring 12. The plate 10 is circular and a peripheral surface 17 thereof which is engaged by the clamping ring 12 is conically tapered. The member 11 includes an annular flange 18, a peripheral surface 19 of which is also conicaly tapered and is engaged by the clamping ring 12. The flange 18 has three arcuate apertures 20 therein which are aligned with the apertures 14 in the plate 10. Heads of the bolts received in the apertures 14, or alternatively nuts engaged with those bolts, are disposed in the apertures 20, the arcuate form of the apertures 20 enabling the member 11 to be rotated relative to the plate 10 without removing the bolts. The clamping ring 12 extends around the periphery of the plate 10 and the member 11, and has a channel 21 in its inner periphery which receives said peripheries. Side walls of the channel 21 which engage the surfaces 17 and 19 are conically tapered. The clamping ring 12 in fact comprises a pair of arcuate parts 22 which are pivotally interconnected. The pivotal interconnection is effected by means of a pair of spaced bushes 23 on an end of one of the parts 22, a single bush 24 on an end of the other of the parts 22, which is accommodated between the bushes 23, and a pivot pin 25 passing through all three bushes 23, 23. Pivotal movement of the parts 22 causes the free ends thereof to move towards and away from each other. The free end of each part 22 is provided with an integral collar 26 having an aperture 27 extending therethrough (see Figure 2) the enagement being such that the apertures 27 are mutually aligned when the free ends of the parts 22 are in juxtaposition. The apertures 27 receive the shank of a bolt 28, the head of the bolt 28 being engaged with an end of one of the collars 26, so that the bolt .28 is held axially captive thereby. A nut is in screwthreaded engagement with the bolt shank, and engages an end of the other collar 26 through the intermediary of a spring washer 30. The bolt 28 and the nut 29 form part of the afore mentioned clamping means, it will be manifest -that rotation of the nut 29 relative to the bolt 28 will cause the free ends of the parts 22 to move towards each other, thereby tightening the clamping ring 12. The bolt 28 is disposed tangentially with respect to the radially outer periphery of the flange 18, and part of the screw thread on the bolt shank constitutes a worm gear and meshes with an arcuate rack 31 formed in said outer periphery of the flange 18. Teeth of the rack 31 are produced by a hobbing operation. In use, the pump is secured against rotation relative to the engine by rotating the nut 29 relative to the bolt 28 so as to tighten. the grip of the clamping ring 12 on the plate 10 and the member 11. However, the pump can be rotated relative to the engine so as to advance or retard the timing of the injection of fuel into the engine, by the pump in the following manner. First, the clamping ring 12 is loosened by rotating the nut 29 relative to the bolt 28. The bolt 28 is then rotated, and the worm-gear constituted by the screw threading thereon acts on the arcuate rack 31 so as to rotate the member 11 relative to the plate 10. It will be manifest that a known rotation of the bolt 28 will cause a known rotation of the member 11 relative to the plate 10, and therefore a known rotation of the pump relative to the engine. Consequently, the injection timing can be controlled accurately, the bolt 28 being rotated in one direction to advance the timing and in the other direction to retard the timing. When the pump has been rotated by the desired amount, the bolt 28 is held stationary and the nut 29 is rotated to retighten the clamping ring 12. WHAT WE CLAIM IS:

1. An arrangement for mounting a fuel pump on an internal combustion engine comprising a first member adapted to be secured to the engine, a second member secured to the pump, and clamping means clamping together the first and second members, the clamping means being arranged -when loosened to permit relative rotation between the members and when tightened to prevent such relative rotation, the clamping means including a pair of mutually engaged screwthreaded elements carried by one of the members, one screwthreaded element having a gear form thereon which meshes with a complementary gear form on the other of the members such that rotation of said one element relative to said one of the members when the clamping means is loosened causes relative rotation between the first and

second members in use, the screwthreaded elements being arranged to tighten and loosen the clamping means when relative rotation is effected therebetween in use.

2. An arrangement according to claim 1 in which said clamping means includes a clamping ring which extends around the peripheries of the first and second members, and relative rotation between the screwthreaded elements in use causes free ends of the clamping ring to move towards and away from each other, thereby tightening and loosening the clamping ring respectively.

3. An arrangement according to claim 2 in which said clamping ring is secured against rotation relative to said one of the members and the screwthreaded elements are mounted on the free ends of the clamping ring.

4. An arrangement according to claim 3 including an interengaging projection and recess on said one member and said clamping ring.

5. An arrangement according to claim 4 in which the clamping ring defines a cahnnel which receives the peripheries of said first and second members.

6. An arrangement according to claim 5 in which the side walls of said channel and the surfaces of said first and second members which engage said side walls are tapered.

7. An arrangement according to claim 6 in which said clamping ring is formed in two pivotally connected parts.

8. An arrangement according to any one of the preceding claims in which the gear form on said one screw threaded element is a worm gear and the complementary gear on the other of the members is a rack.

9. An arrangement according to claim 8 in which said pair of screwthreaded elements comprise a nut and bolt, the thread on said bolt constituting said worm.

10. An arrangement for mounting a fuel pump on an internal combustion engine comprising the combination and arragement of parts substantially as described herein with reference to the accompanying drawings.