GB2255158A

GB2255158A - Vehicle bulkhead and pedal-operated actuator assembly.

Info

Publication number: GB2255158A
Application number: GB9109114A
Authority: GB
Inventors: Philip John Guest; Paul Alexander Dykes
Original assignee: MG Rover Group Ltd
Current assignee: MG Rover Group Ltd
Priority date: 1991-04-26
Filing date: 1991-04-26
Publication date: 1992-10-28
Anticipated expiration: 2011-04-26
Also published as: GB9109114D0; GB2255158B

Abstract

The actuator, eg for clutch or brakes, has a body (1) attached to the bulkhead (12) with a spigot (5) thereof extending through an aperture (16) defined in the bulkhead to allow connection of a linkage (27, 28) between the actuator (1) and its pedal (23). The spigot (5) forms a seal with a bore (15) of the aperture (16) rather than a face of the bulkhead (12). The bulkhead (12) may be a detachable portion of the fixed bulkhead. Assembly during manufacture is thus made quicker and easier. <IMAGE>

Description

VEHICLE BULKHEAD AND PEDAL-OPERATED ACTUATOR ASSEMBLY This invention relates to assemblies of vehicle bulkheads and pedal operated actuators and in particular to such an assembly comprising a hydraulic brake actuator which is attached to and passes through the bulkhead.

Conventionally pedal-operated actuators such as hydraulic brake and clutch actuators are assembled to the engine bulkhead of the vehicle from the engine side, a spigot extending from a large servo housing and surrounding a pedal-operated push rod, the spigot and push rod extending through an aperture in the bulkhead to allow the push rod to connect to the foot pedal. The actuator is conventionally attached to the bulkhead so that it seals the aperture by having a flattened face adapted to press against the bulkhead with a gasket interposed and having a series of bolts which pass through the bulkhead from the engine side to the passenger side, nuts being affixed from the passenger side. Tightening of the nuts draws the flattened face of the actuator against the bulkhead and compresses the gasket thereby sealing the aperture.

The foot pedals are bolted to the bulkhead from the passenger side, usually using the same bolts or studs and nuts as are used to attach the actuator in position.

Modern methods of modular vehicle assembly, wherein large assemblies of components are fitted to the vehicle body shell at one time can render access to either side of the engine bulkhead in the region of the foot pedals and actuators difficult. In particular it may not be easy to gain access to bolts or studs attached to or passing through the bulkhead to draw the actuator tight against the bulkhead to form the seal.

According to the present invention there is provided a vehicle bulkhead and pedal-operated actuator assembly, the actuator having a body attached to the bulkhead with a spigot thereof extending through an aperture defined in the bulkhead to allow connection of a linkage between the actuator and its pedal, wherein said spigot forms a seal with a bore of the aperture.

An effective seal of actuator to bulkhead is thus ensured even when precise location of the actuator in relation to the bulkhead in a direction orthogonal to the plane of the bulkhead cannot be ensured.

The spigot may carry a gaiter for connection to the linkage, said gaiter being interposed between the spigot and the bore to form the seal.

The gaiter thus provides a dual function of excluding dirt from the interior of the actuator and providing a seal to seal the aperture.

The gaiter may be of annular cross section and may define at least two axially spaced annular ridges therearound to engage the bore. The axially spaced annular ridges act in the same way as "0 rings" act to form a seal between actuator and bore. The axial spacing of the annular ridges acts to prevent rotation of the actuator about any axis parallel to the bulkhead.

To provide an adequate seal and at the same time locate the actuator the gaiter may be an interference fit with the bore and the outer diameter of the two annular ridges may be greater than that of the bore.

The gaiter may comprise a sealing portion adapted to engage the bore of the aperture and a remainder portion of lesser width and adapted to pass through the aperture upon assembly.

The aperture may be defined within an axially extending portion formed from the bulkhead or from a length of tube passing through the bulkhead which portion or length of tube may be outwardly flared at its end facing the actuator to assist entry of the said spigot therein.

The axial length of engagement of the spigot and tube or portion may be such as substantially to prevent rotation of the actuator about any axis parallel to the bulkhead.

The actuator may be attached to the bulkhead by interengaged male and female members, the direction of insertion of the or each male member being generally parallel to the bulkhead. This arrangement allows attachment of the actuator to the bulkhead in conditions of reduced access as the length of a male member, for example a stud or bolt, need not be accommodated between the actuator and the bulkhead. In this arrangement holes in spaced brackets on one of the actuator and bulkhead may be aligned with one or more holes in a boss on the other of the actuator and bulkhead and at least one male member may be inserted in the or each set of aligned holes.

A portion of the bulkhead surrounding the aperture may be detachable from the remainder of the bulkhead and may be affixable to a foot pedal assembly comprised in a fascia assembly for the vehicle, said fascia assembly being thereby at least partly supported by the bulkhead through said attachment of the detachable portion of the bulkhead to the remainder thereof. In this way the portion of the bulkhead surrounding the aperture, which may need attachment of both bracketry and tube, may be manufactured more simply off the vehicle and simply bolted on or otherwise attached to the fascia assembly.

The linkage may include a snap fit pivotal connection between the actuator and its pedal. In particular the linkage may comprise a link member extending from the actuator through the gaiter for pivotal connection to the pedal by a pedal-mounted member, said connection comprising a pair of trunnions on one member engaged with limbs of a bifurcated portion on the other member, each limb comprising a slot to receive and support a trunnion in a load-bearing manner at a closed end of the slot and comprising an apertured sprung member extending across the slot, said aperture being aligned with said closed end of the slot and positioned to receive a trunnion therein when same is in an operative position at the end of the slot, said sprung member being resiliently displacable to an open position by the trunnion upon passage thereof along the slot, during fitting, and snapping closed to secure the trunnion in the operative position.

An easy snap connection between the pedal and the actuator linkage is thus achieved facilitating installation of the fascia assembly to the vehicle bodyshell.

Each sprung member may have a leading flare such that entry of the trunnion into the slot displaces the member by engagement with the flare to allow the trunnion to pass along the slot to the end thereof. Snap connection is thus further facilitated.

The invention will now be described by way of example with reference to the accompanying drawings of which: Figure 1 is a side elevation, partly cutaway and in section, of a vehicle bulkhead and pedal-operated actuator assembly with connecting pin engaged, according to the invention, Figure 2 shows the actuator of Figure 1 in plan without the bulkhead and with the connecting pin disassembled therefrom, and Figure 3 is a side elevation of the bulkhead of Figure 1 attached to part of a pedal assembly, Referring to Figures 1 and 2, the actuator comprises a body 1 and has a boss 2 with a pair of holes 3, 4 therethrough. The body also comprises a hollow spigot 5 extending from the boss 2.

The spigot 5 carries a flexible gaiter 6 having a sealing portion 7 comprising a pair of annular ridges 8, 9 axially spaced from one another. The gaiter 6 also comprises a remainder portion 10 of lesser diameter than the sealing portion 7, the remainder portion having a series of corrugations 11 to accommodate changes in length.

The bulkhead 12 comprises a detachable portion of a fixed engine bulkhead of the vehicle (not shown). The bulkhead 12 is attached to the fixed engine bulkhead by studs 13 (see Figure 3).

The bulkhead 12 has a length of tube 14 passing therethrough. The tube is welded to the bulkhead 12. The tube 14 has a bore 15 defining an aperture 16 therethrough. The bore 15 is of the same diameter as the annular ridges 8, 9 of the gaiter 6. The bore 15 of the tube 14 forms a seal with the spigot 5 of the actuator body 1 by means of the gaiter 6 interposed between the tube and spigot. The diameter of the annular ridges 8, 9 and the bore 15 being identical, there will exist an interference fit between tube and gaiter upon assembly and a seal will be formed. The axial length of engagement of the spigot 5 and tube 14 through the medium of the gaiter 6 interposed therebetween acts to substantially prevent rotation of the actuator about any axis parallel to the bulkhead.The gaiter 6 comprises a cylindrical end portion 17 which further assists sealing and gives radial support to the actuator within the tube.

The tube 14 has an outward flare 18 to assist entry of the spigot 5 and gaiter 6 therein during assembly.

Referring to Figures 1, 2 and 3, the bulkhead 12 has a spaced pair of brackets 19 attached thereto for engagement with either side of the boss 2 of the actuator body 1 to attach the actuator to the bulkhead. Each bracket 19 defines two holes 20, 21 which align with the holes 3 and 4 of the boss 2 upon assembly. A pair of bolts (not shown) is then inserted through the aligned holes 3, 4 and 20, 21 to secure the actuator to the bulkhead. Each bracket 19 has an outwardly flared leading edge 22 to assist in insertion of the boss 2 of the actuator body 1 between the brackets 19 upon assembly.

Each hole 20, 21 is surrounded by a roughened portion (not shown) to aid grip.

A brake pedal 23 is pivotally mounted at 24 to a bracket 25. The brake pedal 23 defines an aperture 26 therethrough to receive a pin member 27 as an interference fit therein.

A linkage between the actuator and the brake pedal 23 comprises a link member in the form of a push rod 28 engageable with the pin member 27 on the brake pedal 23.

Referring to Figures 1 and 2, the push rod 28 is connected by a nut 29 to a bifurcated portion 30 of the linkage.

The bifurcated portion has a pair of limbs 31 each having a flared slot 32 extending from a leading end 33 to a circular load bearing end portion 34 thereof.

A sprung member 35 extends across each slot 32 and defines an aperture 36 therein. Each sprung member 35 has a leading flare 37.

The bifurcated portion is adapted to engage the pin member 27 secured through the brake pedal 23. The pin member 27 comprises a central portion 38 and a pair of trunnions 39 of lesser diameter extending from either end of the central portion. Each trunnion has a domed end 40 for engagement with the leading flare 37 of each sprung member 35 during assembly. Upon pushing the bifurcated portion 30 of the linkage against the pin member 27 on the brake pedal 23 each trunnion 39 will engage the leading flare 37 of its sprung member 35 and force the sprung member outwardly. The central portions will then slide along the flared slots 32 in each limb of the bifurcated portion expanding the sprung members in the process.When each trunnion reaches the end of its slot 32 it aligns with an aperture 36 in its sprung member 35 and the sprung member snaps against its adjoining limb to lock the pin in position. It will be appreciated that connecting of the linkage only involves a pushing action on the part of the operator and can thus be extremely quickly and easily achieved.

Because the load from the brake pedal is transmitted through the limbs 31 of the bifurcated portion 30 to the push rod 28 the sprung members 35 do not transmit these high loads but only serve to locate the pin member 27 in position in the bifurcated portion.

From the above it will be understood that assembly of the actuator to the bulkhead and push rod to brake pedal is extremely quick and simple with leading flares 18, 22 and 37 assisting engagement of all parts together. The resilience of the gaiter material acts adequately to locate the actuator in position before the bolts are slid through the holes 3, 4 and 20, 21 but to allow sufficient play for any minor misalignments to be manually corrected by the operator. The push rod 28 is pivotally connected to the actuator to cater for misalignment owing to brake pedal movement.

Claims

1. Vehicle bulkhead and pedal-operated actuator assembly, the actuator having a body attached to the bulkhead with a spigot thereof extending through an aperture defined in the bulkhead to allow connection of a linkage between the actuator and its pedal, wherein said spigot forms a seal with a bore of the aperture.

2. Assembly as in claim 1 wherein said spigot carries a gaiter for connection to the linkage, said gaiter being interposed between the spigot and the bore to form the seal.

3. Assembly as in claim 2 wherein the gaiter is of annular cross section and defines at least two axially spaced annular ridges therearound to engage the bore.

4. Assembly as in claim 2 or 3 wherein the gaiter is an interference fit with the bore.

5. Assembly as in claim 4 when dependant upon claim 3, wherein the outer diameter of the two annular ridges is greater than that of the bore.

6. Assembly as in any of claims 2 to 5 wherein the gaiter comprises a sealing portion adapted to engage the bore of the aperture and a remainder portion of lesser width and adapted to pass through the aperture upon assembly.

7. Assembly as in any preceding claim wherein the aperture is defined within a length of tube passing through the bulkhead.

8. Assembly as in claim 7 wherein the length of tube is outwardly flared at its end facing the actuator to assist entry of the said spigot therein.

9. Assembly as in claim 7 or 8 wherein the axial length of engagement of the spigot and tube is such as substantially to prevent rotation of the actuator about any axis parallel to the bulkhead.

10. Assembly as in any preceding claim wherein the actuator is attached to the bulkhead by interengaged male and female members, the direction of insertion of the or each male member being generally parallel to the bulkhead.

11. Assembly as in claim 10 wherein holes in spaced brackets on one of the actuator and bulkhead are aligned with one or more holes in a boss on the other of the actuator and bulkhead and at least one male member is inserted in the or each set of aligned holes.

12. Assembly as in any preceding claim wherein a portion of the bulkhead surrounding the aperture is detachable from the remainder.

13. Assembly as in claim 12 wherein said detachable portion of the bulkhead is affixable to a foot pedal assembly comprised in a fascia assembly for the vehicle, said fascia assembly being thereby at least partly supported by the bulkhead through said attachment of the detachable portion of the bulkhead to the remainder thereof.

14. An assembly as in any preceding claim wherein the linkage includes a snap fit pivotal connection between the actuator and its pedal.

15. An assembly as in claim 14 wherein the linkage includes a link member extending from the actuator through the gaiter for pivotal connection to the pedal by a pedal-mounted member, said connection comprising a pair of trunnions on one member engaged with limbs of a bifurcated portion on the other member, each limb comprising a slot to receive and support a trunnion in a load-bearing manner at a closed end of the slot and comprising an apertured sprung member extending across the slot, said aperture being aligned with said closed end of the slot and positioned to receive a trunnion therein when same is in an operative position at the end of the slot, said sprung member being resiliently displacable to an open position by the trunnion upon passage thereof along the slot, during fitting, and snapping closed to secure the trunnion in the operative position.

16. Assembly as in claim 15 wherein each sprung member has a leading flare such that entry of the trunnion into the slot displaces the member by engagement with the flare to allow the trunnion to pass along the slot to the end thereof.

17. Vehicle bulkhead and pedal-operated actuator assembly substantially as described herein with reference to the accompanying drawings.