FR2504071A1 - DRIVING AND BEARING MECHANISM FOR MOTOR VEHICLES, IN PARTICULAR A FOUR DRIVE WHEELS - Google Patents

Abstract

TRANSMISSION AND BEARING MECHANISM FOR MOTOR VEHICLES. THE FRONT DRIVE UNIT AND THE REAR UNIT OF A MOTOR VEHICLE, IN PARTICULAR FOUR-WHEEL DRIVE, ARE EACH PLACED ON A SADDLE. THE FRONT SADDLE 21 IN THE DIRECTION OF TRAVEL SUPPORTS THE FRONT UNIT BY MEANS OF TWO BEARINGS 10, 11 AND THE REAR UNIT BY MEANS OF A SINGLE BEARING 12. THE BEARINGS ARE PLACED AS TO BE OBTAINED, IN COOPERATION WITH A COMPLIANCE AS A WHOLE, A VIBRATORY COORDINATE SYSTEM.

Description

Driving and rolling mechanism for motor vehicles

  biles, especially four-wheel drive.

  The present invention relates to a drive mechanism

  rolling stock for motor vehicles, in particular four-wheel-drive vehicles, comprising a gear-motor unit located at the front, held on a support device

  and in elastic support on the vehicle body, rigidly connected-

  by means of a flexion and torsion rigid connecting beam receiving the transmission shaft to a transmission unit located at the rear, held on another support device and resting on the vehicle body , the

  suspension of the wheels being hinged to the support devices.

  German publication 23 60 514 discloses a drive device for a motor vehicle with the rear-wheel drive wheels. In this case, this device comprises a motor-gearbox unit located at the front rigidly connected, via a rigidly rigid bending beam, carrying a transmission shaft and shaped as a torsionally rigid tube, to a rear transmission unit. In this known arrangement, the front drive unit and the rear drive unit are placed directly on the body, each by means of two bearings, the suspension of the wheels being hinged to the body The support of the driving groups is made statically redundant by the four points of support, so that it is necessary, during the mounting, precise positioning

  to obtain a system that can be determined in terms of vibrations.

  This is all the more necessary as it can be done locally.

  precisely configurable vibratory zones, to obtain a coordinated installation of the groups from the point of view

vibratory.

  It is further known from German Patent No. 887,608

  a four-wheel drive vehicle comprising a group of

  dragging at the front rigidly connected to a group of

  trainement located at the back by a connecting spar.

  These groups each rely directly on the cashier

  by two elastic bearings located in a transverse plane.

  DE-OS 17 80 564 discloses a motor vehicle with rear-wheel-drive wheels comprising a fifth wheel for retaining a drive assembly, as well as for receiving the guiding and suspension members of

  drive wheels The training set is maintained in all

  on the fifth wheel by means of a large number of elastic supports of expensive construction and assembly, arranged near the longitudinal axis of the vehicle and at a distance one behind the other. Such an arrangement bearings or bearings is disadvantageous to the extent that one can not obtain a favorable position vibratory points of attachment to the chassis by the separate locations

bearings.

  The subject of the invention is a transmission and rolling mechanism, in particular for a motor vehicle with four

  driving wheels, of the aforementioned type, in which any system of

  training units is determined from the vibrational point of view

  and isolated from the bodywork, and whose cost of construction

  truction and assembly is reduced.

  To achieve this objective, according to the invention, the

  appears from the drive unit is maintained on the devices

  supports by means of a three-piece elastic suspension

  points arranged substantially at the outer oscillation nodes

  of the block, which comprises two anterior bearings spaced from one another in a horizontal plane and another rear bearing disposed on the longitudinal axis of the

  vehicle and near the gravity line of the unit and

  unit is connected by this level via a dynamic link

  only weak in the vertical direction and the transverse direction, but more rigid in the longitudinal direction, the support device Other variants of the invention will emerge from the

description that will follow.

  In a four-wheel drive vehicle in which

  the drive unit at the front is connected by a long

  rigid flexion and torsion link to a rear drive unit, the forces generated by

  the gases and the forces of inertia of the engine generate vi-

  system-wide vibrations These vibrations, which are

  Actually, apart from the torsional vibrations, bending vibrations, would urge the bearings relatively relatively in the case of a vibratory non-concordant disposition.

  of these, as is the case with known and

  would produce vibrations that lessen comfort.

  Thanks to the layout and the particular number of

  bearings on an anterior saddle and a later harness

  re, as well as to their realization in accordance with the vibratory data of the entire system, we obtain a placement of the entire drive unit determined statically by the three-point suspension The arrangement of the bearings at the nodes oscillation in the most externally possible position permitted by construction give not only a

  vibration-free installation, but also a place-

  on the saddles with a relatively large support base.

  So that the harness can not strengthen vibra-

  tions, it is shaped as a carrier structure without resonance.

  For this purpose, the beams and cross members are formed

  two sections forming a closed section or an open angular profile In particular, in order to reinforce the posterior saddle, the latter has on its crossbar at the location of less rigidity transverse partitions which serve at the same time to receive the Unique rear bearing To further eliminate the transmission of residual vibrations from the fifth wheel to the bodywork, each fifth wheel is elastically held at the locations of high mechanical impedance,

  as for example on the spars of the carros-

series.

  To place the single rear bearing between the drive unit and the saddle as close as possible to the longitudinal axis and, consequently, near the center of oscillation, it is integrated in the casing. For this purpose, the casing comprises a wall constituting at the same time a housing wall of the bearing, so that one obtains mounting advantages, while

  maintaining maximum rigidity of the housing.

  To compensate for tolerances in the longitudinal direction

  of the entire group, the transverse keys

  wear slit-shaped housing for the bolts of

fixing the bearing.

  To obtain the desired rigidity of the entire system, the housings of the two differentials are made so as to have corresponding stiffnesses For this purpose, they comprise stiffening ribs to bending and torsion which constitute a dynamically rigid bearing structure The transmission and rolling mechanism according to the invention has, compared to known arrangements, such as that of the German publication 17 80 564 above, thanks to the reduced number of support points on the drive unit. , a reduction in construction and assembly costs, complemented by noise reduction In addition, the transmission of oscillations caused by the forces of gases

  and the inertial forces of the motor, appearing

  in certain ranges of rotational speeds, is avoided, because the three-point suspension is placed in areas without oscillations, including existing oscillation nodes In addition, the bearings rely on the saddles that are made for do not go into resonance and play

  in addition the role of stop mass for oscillations resi-

possible duels.

  We will now describe in more detail an example of non-limiting embodiment of the invention, with reference to the appended drawing, of which:

  Fig 1 is a schematic side view of a mechanical

  transmission and rolling system according to the invention; Fig 2 is a schematic top view according to Fig 1; Fig 3 is a side view of the rear gearbox housing with a bearing housing, in section;

  Fig 4 is a sectional view of a spar or

the posterior harness;

  Fig. 5 shows another embodiment of

  geron or crosses, in section; Figure 6 is a section along the line VIVI of Figure 2, a cross member of the rear seat comprising a differential housing shown in section;

  Fig. 7 is a schematic front view of the work

  pouring the posterior saddle, in the direction of arrow Z of Fig 2;

  Fig 8 is a side view of the differential housing;

with its ribs.

  FIG. 1 shows a transmission mechanism

  The invention relates to a drive unit 1 comprising essentially an internal combustion engine 2 with a gearbox 3 and a differential 4, with respect to the direction of travel. , this unit 1 being rigidly connected to the means

  a connecting spar 5 to a unit 6 located at the rear.

  This essentially comprises another differential 7.

  The anterior unit 1 is connected to a device for

  port 8 and the posterior unit 6 to another support device 9 by elastic bearings 10, 11 and 12, these support devices 8,9 each bearing elastically by bearings 13 to 16 and 17 to 20 on the bodywork or the vehicle body It is also possible to ensure the placement of the support devices by three bearings each. The wheel guiding members are articulated to the support device, which has not been shown.

in detail.

  The drive assembly 1, 5 and 6 is held on the support devices 8, 9 made in the form of saddles 21, 22, by a suspension (a support or placement) at three points

  , 11 and 12 The points of support are each respectively

  stained to the outer swing knots of the unit that is

  found in plans A-A and B-B and also occupy a position

  such that the structural arrangement of the bearing on the crankcase concerned is still favorable. The position of the knots

  oscillation in the A-A and B-B planes over the entire system.

  is essentially influenced by the conformation of

  gidity and mass distribution of the whole system.

  The three-point suspension 10, 11, 12 is made in such a way that the front fifth wheel (with respect to the direction of travel) 21 comprises two elastic bearings 10 and 11 placed in a horizontal transverse plane and at a distance from one of the other. The rear saddle 22 comprises another single bearing 12 which is placed on the longitudinal axis 23 of the vehicle

  and near the gravity line of the set 1, 5, 6

  will always lera in the following, a single bearing 12, but one could also consider that two bearings located close to each other constitute this single bearing 12 It has a characteristic such that the assembly 1, 5, 6 is connected to

  the harness by a dynamically flexible link in the direction

  vertical direction 24 and the transverse direction 25, but stiffer in the longitudinal direction 26 To obtain this

  characteristic, the bearings have recesses

  corresponding forms or various stiffening means.

  The support of the saddles 21, 22 on the body is preferably made in areas of relative mechanical impedance

  high, which exists in particular on the longitudinal members of the structure

bodywork.

  Saddles 21 and 22 constitute a structure

  non-resonant machine essentially comprising closed hollow sections 28 and 29 respectively (FIGS. 4 and 5) The bearing structure of the posterior saddle 22 comprises in the embodiment shown longitudinal beams 30 and crosspieces 31.

  together by forming, for example, a rectangular shape

  In this embodiment, the anterior cross member 31a is, for example, shaped as an open U-section cross section.

  the two longitudinal members 30 comprising with the other cross-member

  31 a closed profile and having a U-shape whose free ends of the branches are connected by the cross members 31 One could also imagine a carrier structure of the fifth wheel or trapezoidal shape comprising beams that intersect and connected together at the ends by

  another beam The support points 10, 11 and 12 of the suspension

  three points on saddles 21 and 22 are

  each (in relation to the direction of travel) on the an-

  31 a, respectively 31, of the fifth wheel 21, respectively

22.

  FIGS. 1 and 6 show an embodiment of the rear bearing 12 with its bearing housing 32 in the housing 33 of the differential 7. The housing 32 is integrated in the housing 33 because the housing wall is shaped in housing 32 closed peripherally Another embodiment of the housing 32 not shown comprises an open housing closed by a corresponding plate which maintains the

bearing 12 in housing.

  The bearing 12 is held in the housing 32 of the housing 33 of the differential 7 and is connected to the anterior cross member 31 of the posterior saddle 22 by transverse partitions.

  34 to the anterior cross member 31 of the posterior saddle 22.

  The transverse partitions 34 serve not only to ensure

  link with step 12, but also with

  necessarily for the crossbar 31 made in the form of a profi.

  open and U-shaped cross section (Figure 6).

  The versales 34 have slots 45 directed along the length of the unit, for the fixing bolts 44 of the bearing 12, to compensate for the assembly tolerances of the whole unit in the longitudinal direction. The housings 33 and 43 differentials 4 and 7 (FIGS. 8 and 9) are made to have an effect on the rigidity of the entire system, with regard to the positioning of the oscillation nodes in the

  plans A-A and B-B and, consequently, points of

  ters or saddles, with torsional rigidity and desired bending. It is obtained by a corresponding ribbing

  realized so that for example, on the earlier differential

  4, the casing 43 has ribs 35 to 39. They are placed so that, for example, the rib 35 is

  the point of attachment 40 of one of the front faces of the car-

  ter 43 at the point of attachment 41 of the opposite end face.

  The other ribs are also arranged so as to realize

  a link consistent with the flow of force between locations

  fastening elements of the two front faces Similarly, the housing

  33 of the rear differential 7 comprises stiffening ribs

  torsional and flexural deformation.

Claims (1)

1 Driving and rolling mechanism for motor vehicles, in particular four-wheel-drive, comprising a motor-gearbox assembly located at the front, held on a support device and resilient support on the body of the vehicle, rigidly connected by means of a flexural and torsion rigid spider receiving the transmission shaft to a rear-mounted transmission unit, maintained on another device support and resting on the vehicle body, the suspension of the wheels being articulated to the support devices, characterized in that the entire drive unit (1,5,6) is held on the devices. of support (8, 9) by means of a three-point elastic suspension (10 to 12) arranged substantially at the respective external oscillation nodes (planes AA and BB) of the group (1, 5, 6) which comprises two prior liers (10, 11) arranged at a distance to one another in a horizontal plane and another rear bearing (12) disposed on the longitudinal axis (23) of the vehicle and near the gravity line of the group (1, 5, 6), and the entire group (1, 5, 6) is connected by this bearing (12) by a dynamically weak connection in the vertical direction (24) and the transverse direction (25), but is more rigid in the direction longitudinal member (26) to the support device (9). 2 Mechanism according to claim 1, characterized in that the distribution of the masses of the whole unit (1, 6) is such and determined for the rigidity so that the bearings (10 to 12) are at oscillation nodes (planes AA and BB) are arranged with a large base at the locations permitted by construction of the anterior unit (1) and the posterior unit (6) or on the support devices (8 and 9). ). 3 Mechanism according to any one of claims 1 and 2, characterized in that the prior support device (with respect to the direction of travel) (8) and the posterior support device (9) are each shaped as saddles ( 21, 22) and have a bearing on the body in areas with relatively high mechanical impedance. 4 Mechanism according to claim 3, characterized in that each fifth wheel (21, 22) is shaped as a load-bearing structure without resonance and comprises longitudinal members and interconnected cross-members, formed as hollow profiles and closed profiles (28, 29, 30, 31, 31 a). Mechanism according to the set of claims 1 to 4, characterized in that the support of the saddles (21, 22) on the body is realized in each step in at least three points of support, the support of the unit d anterior drive (1) and that of the rear unit (6) each located respectively on the front cross member (31, 31 a) of the saddle (21, 22) (relative to the direction of travel). 6 Mechanism according to any one of the preceding claims, characterized in that the rear housing (33) of the differential (7) (relative to the direction of travel) or the gearbox of the rear unit (6) comprises a housing (32) for the bearing (12) integrated in the housing (33). 7 Mechanism according to claim 6, characterized in that the housing (32) constitutes a portion of the housing wall (33) and is closed peripherally. 8 Mechanism according to all of claims 6 and 7, characterized in that the housing (32) is placed near the longitudinal axis of the transmission shaft in the housing (33). 9 Mechanism according to any one of the preceding claims, characterized in that the cross member (31) of the rear selector (22) is connected approximately in its zone of lesser hardness to transverse partitions (34) for re - see the bearing (12), placed in a vertical transverse plane. Mechanism according to claim 9, characterized in that the transverse bulkheads (34) comprise, to compensate for the tolerances of the unit (1, 5, 6), longitudinal slots (45) for receiving fixing bolts ( 44) for the bearing (12). Mechanism according to any one of the claims   1 to 10, characterized in that the housing (43) of the differential   (4) of the front unit (1) and the housing (33) of the   each (7) of the rear unit (6) is each part of the connecting spar (5), and in that the housings have bending and torsion stiffening ribs (35 to 39). Mechanism according to claim 11, characterized   in that the ribs are directed longitudinally and trans-   are partly connected to each other and form   a dynamically rigid support structure, the places of fixa-   (40, 41) to the front faces of the housing (33 and 43) being   interconnected in accordance with the flow of force.