FR2650228A1 - BRIDGE, IN PARTICULAR FOR MOTOR VEHICLE - Google Patents

Abstract

This bridge 8 is in particular intended for a fully propelled vehicle, in which the rear wheels are connected to the kinematic chain 7 via a torque divider. The bridge can be engaged or disengaged by an actuating means 50. The invention aims to couple the control devices so that the two rear wheels cannot be in different control states. For this, an actuator 50 is used which can be pneumatic, hydraulic or electromagnetic and which simultaneously locks the two output shafts 31, 32.

Description

The invention relates to an axle or bridge drive, particularly for

  motor vehicle with integral propulsion, in which the wheels of the front axle are permanently driven by a front axle differential and the drive of the wheels of the rear axle is effected by means of a driveline

  comprising two viscous friction couplers clutch

  disengageable links between the transmission shaft and

  articulation and the rear wheels which are arranged

  in a common housing and have two hubs

  crying so as to be able to turn one

  port & the other and which, constituting the outputs of the bridge, are couples to the wheels for the transmission of torque, the two outputs can be detached from the wheels

  corresponding devices by control devices.

  It is already known to use bridges of this type to replace a differential. Thus, EP 0 216 749 C2 describes a bridge in which the torque transmitted to the corresponding axle is transmitted to the wheel.

  corresponding through two visco-cou-

  tears. In a device of this kind, we have

  advantage of being able to dispense with a high differential

  binaries and conical wheels needed. The fact that

  the hubs of the couplers can turn one

  port and the other makes it possible to compensate for

  that occur between the inner wheel and

the outer wheel in a bend.

  EP 0 333 776 A1 describes another dive-

  Torque splitter in which a torque divider is interposed in the differential collar. This divider device. The function of the torque converter is to separate the axle driven by the torque divider from the other axle or other axles when actuating the brake or by the regulation of an ABS system. appearance of the couple, to prevent the axles from influencing

  mutually during braking. The device

  torque finder described in this document presents the

  convenient that the two wheels of the

  associated with it are momentarily coupled

  they are for the transmission of the couple. In particular, if the above-mentioned axle was previously subjected for a short time to high loads and had to transmit a high torque, it can

  produce that the two visco-couplers which together form

  the bridge are in so-called "hump mode" ("HumpMode"), so they behave at

  the way of a completely locked differential.

  DE 3 317 247 C2 also describes a divider

  torque in which it is intended, in both

  of the bridge leading to the wheels, devices

  broomable and disengageable, in the aspect of the transmission

  couple, and by means of which the two rouas cor-

  riders can be detached from the bridge if this is necessary for the preservation of the stability of the

walking.

  In the bridge version that is described here, a disadvantage is that it can be established

  dangerous conditions when, as a result of

  one of the two devices takes a state of

  order different from that of the other. This situation

  tion can occur, for example, in the case of

  not an actuating means. The result leads L a

  yawing torque around the rear axle, which

  fluence adversely the stability of walking.

  The purpose of the invention is to create a bridge

  of the type cited in which the securing of the wheels as-

  associated with the axle in relation to the transmission bridge

  sion of the couple can not provoke the appearance of

unstable market situations.

  According to the invention, this problem is solved by the fact that the actuating means provided for the control devices are coupled together with respect to the control state in question and in that

  the basic position, not loaded, of means of

  This corresponds to the disconnection control state of the two rear wheels with respect to the kinematic chain.

  In the embodiment of the bridge according to

  an advantage is that no single couple

  lateral influence negatively influencing the running stability of the vehicle can not be established on any of the wheels and that, in the presence of failures of the actuating means,

  the bridge takes the disengaged control state, which eliminates

  securing the two wheels associated with the bridge.

  In an advantageous embodiment of

  the invention, it is intended that the two hubs

  crying can be coupled to the rear wheels by

  a combination of a mechanical control device

  in particular, a zipper, and that the

  Positive control, especially the zipper, can

  charged by a pneumatic actuating means, hy-

hydraulic or magnetic.

  This embodiment guarantees, in a

  extremely simple that a simultaneous disengagement or disengagement of the two wheels occurs

  pneumatic, hydraulic or manual actuating means

  gnétique. According to another characteristic of the invention,

  the two hubs of couplers are controlled internally

  two separate control devices equipped with electromagnetic actuation means and the electromagnetic actuation means associated with the

  control devices are connected in series.

  This embodiment ensures that in pre-

  of a break in the cable or in the event of failure of

  the safety of the corresponding circuit, the two

  Control Units do not respond and are shut down 2 & So0228 simultaneously.

  According to another embodiment of the invention,

  the two hubs of couplers are controlled by means of two separate control devices having hydraulic or pneumatic actuating means.

  and the pressure chambers of the means of

  which are associated with the control devices may

  may be charged with pressure medium through

  of a common pressure channel. This variant of

  realization also ensures that the chambers of

  can be loaded simultaneously with fluid from

  pressure and simultaneously drain.

  Other features and advantages of

  will be better understood when reading the description of

  The following is an example of embodiment and with reference to the accompanying drawings, in which: FIG. 1 is a kinematic diagram of a motor vehicle in which the bridge can be incorporated; Figure 2 is a section of such a bridge equipped with actuating means for the two output shafts of the rear wheels; FIG. 3 is a section of a bridge of this type with electromagnetic actuation for each of the

  output shafts of the rear wheels.

  In FIG. 1, a vehicle is shown

  a four-wheeled tomobile 1 whose engine 2 is connected to the front wheels 6 via a boot

  3 and a front axle differential 4 and

  if only two half-shafts before 5. The driving force is also transmitted to the rear axle, by the differential

  4 of the front axle, through a long shaft

  7. The longitudinal shaft 7 serves to drive a bridge 8 which is itself kinematically connected to the wheels

  13 through the half-shafts of trans-

  mission 14, 15, with the interposition of two joints 9, 10 secured to the bridge and two wheel joints 11, 12. The bridge 8 is described in more detail with respect to the

Figures 2 and 3.

  The bridge 8 of FIGS. 2 and 3 is composed of a bridge casing 16 in which a conical pinion 17 is journalled with the aid of a longitudinal shaft 7, and is connected to a ring gear 18, the ring gear 18 being

  fixedly secured by screws 19 to the housing 20 of the screw

  co-coupler 21. In the housing 20 of the visco-coupler, all

  rillonnate two hubs couplers 22, 23, a set of

  outer discs 24 being fastened integrally in rotation

  coupling casing 20 and two sets of disks

  25, 26 respectively being associated with the hubs 22, 23 of the couplers, and the outer discs 24 being

  alternately mounted with the inner disks 25, 26.

  The hubs 22, 23 of the couplers are mounted with a gasket relative to the casing 20 of the coupler by seals 27, 28. The casing 20 of the coupler

  is in turn mounted in the casing 16 of the bridge by the in-

  Bearings 29, 30. In the housing 20 of the

  Coupler are additionally journalled two

  31, 32 which are connected to the shafts 14, 15 of the rear wheels 3, each via a gasket 9, 10. The seals 9, 10 are each composed of an outer seal member 33, 34 and an element

  inner seal 35, 36 in which is arranged a

  ball bearing 37, 38 which encloses the balls 39, 40 of the

  seal. The transmission shafts 14, 15 of the rear wheels

  re are each engaged by a groove 41, 42 in the corresponding groove 43, 44 of the inner member 36 of the seal. A pleated sbufElet 45, 46 mounted on the transmission shaft 14, 15 encloses a sealed seal

  the seal 9, which is open on one side.

  In Figure 2, there is shown in half

  the engaged or secured condition of the rear wheels

  re 13 and, in the lower half, the disengaged state or

  disengaged from these wheels. The ends 47, 48 of the

  output bores 31, 32 are engaged in the hubs 22, 23 of the couplers and are provided with recesses 49

  in which are arranged support rings 51 of

  spherical which are fixed axially to a zipper or

  to an actuating pusher 50. In the region of

  49, the transmission shafts 31, 32 have through holes 52 in which are held locking elements 53. The actuating pusher

  50 is guided into one of the output trees - here the ar-

  output 31 - and at the end of the output shaft

  tis 31 looking outward, this push is

  axially connected to a membrane 54. The membrane 54 and the seal 75 isolate from the outside a

  pressure chamber 55 which can be loaded through

  In the actuating pusher 50, a spring 56 is arranged which loads the actuating pusher 50 provided with the spherical bearing rings 51 to tend to place them in a position of release of the elements. lock 53, so

  that in this position loaded by

  locking elements 53 can be radially

towards the inside.

  In the through holes 52 of the hubs 22,

  23 couplers, are grooves 57 orien-

  axially in which the locking elements

  53 are held under the action of the support rings sphs-

  51 to kinematically couple the hubs of couplers 22, 23 to the output shafts 31, 32 for

transmission of the couple.

  FIG. 3 shows a bridge 8 which,

  using two electromagnetic actuators4-

  ticks, establishes or removes mating between

  joints 9, 10 of the transmission shafts 14, 15 and the

  31, 32 who are bound by their

  47, 48 in the hubs 22, 23 of the couplers. The dis-

  positive actuation can be advantageously

  sawn in this construction, which ensures simultaneous clutching and disengagement of

  transmission 14, 15. In the lower half of the

  re, there is shown the engaged condition of the rear wheels 13 and, on the upper half, the disengaged state of these wheels. The output shafts 31, 32, have, at their second ends 58, 59, outlet flanges 60, 61 provided with a toothing 62, 63 and a bearing portion 64, 65 radially offset on which trays control 66, 67 are rotatably mounted and arranged movable in the axial direction by means of a plurality of support pins 68, 69 distributed circumferentially. In

  the engaged state, the control plates 66, 67 are

  provided by a corresponding toothing 70, 71 in the den-

  62, 63 of the cylindrical outlet flanges 60, 61

  and they transmit training couples to ar-

  In this case, electro-aids

  Annular heaters 72, 73 which are fixed integrally to the casing 16 of the bridge are supplied with electrical voltage and attract the control plates 66, 67 axially towards the visco-coupler 21, which guarantees the safety

  the meshing of the teeth 62, 63 and 70, 71. The recess

  turn in the disengaged state of the rear wheels 13 is provided,

  after the suppression of the voltage, by the springs

  74, 75 which are fixed, on the one hand, to the trays

  66, 67 and on the other hand to the external

  33, 34 of the joints. The scope pins 69, 69

  are anchored in the outer element 33, 34 of the joints.

  Of course, various modifications may be made by those skilled in the art to the device which

  has just been described by way of non-limiting example

  mitatiE, without departing from the scope of the invention.

RE V E N DI C T IO N S

  1. Axle or bridge drive (8), in particular

  for a motor vehicle, full propulsion, in the

  the wheels (6) of the front axle are permanently driven by a front axle differential (4) and the driving of the wheels (13) of the rear axle is effected via a driveline (7)

  comprising two viscous friction couplers clutch-

  disengageable links between the transmission shaft and

  articulated joint and the rear wheels (13) which are

  in a common housing and have two hubs of couplers (22, 23) mounted rotatably

  relative to each other and which, constituting the

  parts of the bridge, are coupled to the wheels (13) for transmitting

  couple's mission, the two outputs being desolate

  of the corresponding wheels (13) by means of

  control devices, characterized in that the actuating means (50, 72, 73) provided for the control devices are coupled together with respect to the control state and in that

  the basic position, not loaded, of the means of

  (30, 72, 73) corresponds to the command state de-

  two rear wheels (13) with respect to the cat-

do kinematics (7).

  2. Bridge according to claim 1, characterized in that the two hubs of couplers (22, 23) can

  coupled to the rear wheels (13) via the

  of a common mechanical control device, in par-

especially, a zipper.

  Bridge according to claim 1, characterized

  in that the two hubs of couplers (22, 23) are wedged

  through two control devices

  separations provided with electromagnetic actuation means

  (72, 73), and that the actuating means

  (72, 73) associated with the control devices are con-

nected in series.

  Bridge according to claim 1, characterized

  in that the two hubs of couplers (22, 23) are ac-

  two separate control devices equipped with hydraulic or pneumatic means, and in that the pressure chambers of the actuating means which are

  associated with the control devices may be

  pressure fluid through a means of

common pressure.