FR2798179A1 - Operating unit for mechanical gearbox comprises method of blanking off opening in housing consisting of two parts placed on either sides of seal - Google Patents

Abstract

Control (5) has housing (1) comprising two actuators controlling displacement of part of moving pieces. Control contains method of blanking off opening in housing consisting of two parts : primary part (6) placed on one side of seal provided with elements that come in contact with mobile pieces, and second part (7) placed on the other side of seal and provided with elements designed to be connected with exterior operating units to gearbox. An Independent claim is also included for the gearbox.

Description

FIELD OF THE INVENTION The invention relates to the field of gearboxes for motor vehicles and their control device.

In known manner, a motor vehicle gearbox comprises at least two primary and secondary longitudinal parallel shafts, of the type comprising at least two gears in each of which an idle gear, rotatably mounted on the first shaft, meshes with a fixed pinion carried by the second shaft and of the type comprising means for interconnecting each idle gear on its shaft by means of axially movable coaxial rings, under the action of control means comprising control forks which are slidably mounted parallel to the shafts. Each fork provided with a transverse foot at the end of which is arranged a contact key, the keys being aligned transversely in a circular arc to be received in a fork of an actuator which is capable of being controlled in transverse displacement following a circular arc to select a range associated with a gear ratio, and parallel to the shafts to engage the gear associated with the selected range by moving longitudinally a clutch ring of the idler gear corresponding to this ratio.

Numerous gearboxes are known that comprise control means for the interconnection of idle gears on the shafts carrying them, to cause them to mesh with associated fixed gears belonging to at least one other shaft and to thus selectively engage specific gear ratios. associated with said idler gears. The gearboxes for automobiles conventionally make use of interconnection devices with synchronizers of the type previously mentioned. The synchronizers are capable of being displaced axially by forks, carried by axes, and capable of being actuated longitudinally by the driver of the vehicle by means of a gearshift lever arranged inside the vehicle. cabin of the vehicle. In the case of a so-called "manual" gearbox, the shift lever actuates a linkage which acts directly on the forks, and in the case of a so-called "robotic" or automated transmission, the shifting lever indirectly controls the movement of the forks, in particular by means of jacks or other types of actuators. Such a device is described in document FR A 2 609 138.

This document describes more particularly an automated gearbox architecture in which the interconnection of the idler gears on their shaft and the movement of the synchronizers parallel to this shaft is achieved by forks whose translational movement is controlled by actuators, by the intermediate control keys integral rods passing through the gearbox housing. Each fork is moved by an associated actuator. This arrangement is particularly cumbersome because it requires a large number of forks, fork shafts and actuators.

To reduce the size of such devices and reduce manufacturing costs, it has been proposed to use a dual rotolinear actuator to control consecutively the movements of several forks. Such a device is described in document DE A 3,600,185. An actuator mounted externally to the casing of the gearbox is integral with an arm which passes through said card at the end of the arm. A key is capable of being displaced in rotation. and in translation to select a fork and engage the report associated with the fork considered by moving it parallel to the shaft of the box. This device remains bulky because of the multiplicity of the axes of forks and their transverse distribution.

The present invention aims to overcome the disadvantages mentioned above.

The invention relates to a particularly compact control device for gearboxes.

control device, according to the invention, is intended for mechanical gearbox provided with a housing and moving parts arranged in the housing. The control device comprises at least two actuators able to control the displacement of at least a portion of said moving parts. The control device comprises means for closing off an opening provided in the casing of the gearbox, the shut-off means defining two parts of the device controls a first part arranged on one side of the shut-off means and provided with elements intended to come into contact with at least a part of said moving parts, and a second part arranged on the other side of the closure means and provided with elements intended to be connected to external members to the box of speeds. It is thus possible to integrate the actuators to the gearbox and to arrange some or all of them inside the casing.

Advantageously, the control device comprises a frame provided with a flat surface adapted to cooperate with a concordant surface of the housing of the gearbox to ensure the closure. Said flat surface may be provided with a seal. The sealing means are greatly simplified inasmuch as the control device according to the invention is simply provided with a static seal while according to the prior art the different control axes had to be provided with dynamic seals. because of their displacement in translation and in rotation.

In one embodiment of the invention, the control device comprises a plurality of control fingers and a rod integral with said fingers, a first actuator being able to move the rod in translation, and a second actuator being able to move the rod in rotation, each finger being intended to actuate a fork of the gearbox.

Advantageously, the first actuator is hydraulic. Alternatively, it could also provide a first actuator of the electric type. The second actuator may be hydraulic or electric. In a particular embodiment, the second actuator will be a motor not equipped with a gear meshing with a corresponding toothing integral with said rod so that said motor pitch can drive the rod in rotation.

In another embodiment of the invention, the control device comprises a plurality of control fingers, each finger being integral with the moving part of a linear actuator, so that each actuator is able to control a single fork of the actuator. gearbox. Thus, each actuator is dedicated to a particular range, which can simplify the arrangement of the ranges.

Advantageously, the control device comprises an additional actuator adapted to control a release means integral gearbox. Indeed, the control device forms a block supplied with hydraulic and electrical power on which the addition of an additional actuator is simpler and less expensive than the addition of an additional independent actuator on the clutch. control transmission means such as a linkage may provide the connection between the additional actuator and the clutch, including disengagement stop of the control fork.

Another subject of the present invention is a gearbox provided with a housing, moving parts arranged in the housing and a control device comprising at least two actuators able to control the displacement of at least a portion of said moving parts, casing being provided with an opening for receiving the control device. The control device comprises means for closing an opening provided in the casing of the gearbox, the shut-off means defining two parts of the control device, a first part arranged on one side of the closing means, the interior of the housing, and provided with elements intended to come into contact with at least a portion of said moving parts, and a second portion disposed on the other side of the closure means outside the housing, and provided with elements intended to be connected to external bodies to the gearbox.

Thus, the movable portion of the actuators is directly disposed in the housing of the gearbox, which greatly simplifies the transmission of movements and reduces the number of parts and their mass' a simplification of the entire gearbox, and a reduction in the energy consumption of the transmission control. fixed part of the actuators may be arranged in part or in full inside the housing of the gearbox.

The present invention will be better understood from the study of the detailed description of some embodiments taken by way of non-limiting examples and illustrated by the accompanying drawings, in which FIG. 1 is a partial sectional view of the gear box housing. speeds provided with an opening in which control device is installed; Figure 2 is a cross-sectional view of a gearbox according to the invention; and FIG. 3 is a partial perspective view of a control device according to the invention.

As can be seen in FIG. 1, the gearbox comprises a casing 1 of which only a portion is shown, the casing 1 being in the form of a hollow body of relatively small thickness relative to its volume and provided with an opening 2. The opening 2 is defined by a flange 3 integrally formed with housing walls and slightly projecting relative to the wall from which it is derived. The rim 3 has a flat surface 4 formed on the outer casing side 1. For example, the flat surface 4 may be of rectangular shape and of relatively constant width while surrounding the opening 2.

A control device 5 is fixed to the casing 1 and partially protrudes inside said housing 1 through the opening 2. With respect to the plane of the surface 4 which is shown in phantom, the control device 5 comprises a first portion disposed on the inner side relative to said plane of the surface 4, that is to say inside the casing 1, and a second portion 7 disposed on the other side of said plane, that is to say ie, on the outside of the casing 1. The two parts 6 and 7 are defined conventionally but can be made from a frame or a single casing. The second part 7 comprises a peripheral flat surface 8 of the same dimensions as the flat surface 4 and intended to come into contact with said flat surface 4 during mounting of the control device 5 on the casing 1. The attachment can be provided by screws, not shown, passing through the second part 7 and engaging in tapped holes, not shown, of the rim 3 of the casing 1. The contact between the surface 8 of the control device 5 and the surface 4 of the casing 1 must be sealed . For this purpose, there may be disposed between the surfaces 4 and 8 a static seal, not shown and disposed around their periphery. This avoids any leakage of the lubricant disposed in the gearbox.

The second part 7 of the control device 5, may be supplied with energy from other elements of the vehicle by means of electrical, hydraulic or pneumatic connections. Similarly, one or more electrical signal transmission links may be provided, for example to exchange information with a motor calculator.

The first part 6 of the control device 5 comprises several actuators which are shown in FIGS. 2 and 3 and which may be partially arranged in the second part 7, their moving part projecting on the side of the first part 6 inside the casing. 1.

In Figure 1, we see that a rod 9 projects laterally from the first portion 6 and is extended by a finger 10. The finger 10 is provided to come into contact with a control key of a not shown fork. The finger 10 may affect the shape of a fork, each branch of which will come on both sides of the control key. The rod 9 and the finger 0 can be formed integrally and constitute the movable part of a rotolinear actuator disposed inside the control device 5. The translational movement of the rod 9 and the finger 10 makes it possible to select the fork to be operated while the rotation of the rod 9 and the finger 10 allows to actuate the selected range whose control key is engaged between the two branches of the finger 10. reference can be made to DE A 3 600 185 for a more precise description. On the other side of the first part 6, is provided a rod 11 which constitutes the movable part of a linear actuator arranged the control device 5 and which is intended to be connected by a linkage, not shown, to a clutch in view of the control of said clutch.

Of course, the dimensions of the opening 2 will be determined so that the first part 6 can pass said opening 2 during assembly. The control device 5 can also be equipped with a transmission computer which will control the various actuators. The engine computer can also be integrated inside the control device 5. Thus, it can be seen that the control device 5 forms a compact assembly mounted with a simple static seal on the gearbox casing 1 and permits mass, number of parts and cost due to the simplification of the control mechanism of the gearbox, the moving parts of the actuators being able to directly attack the forks themselves or control elements formed integrally with the forks .

In Figure 2, we see the control device 5 mounted on the housing 1 of a gearbox sectional view. The gearbox comprises a plurality of gears 12 which is shown schematically and whose arrangement is well known in a gearbox provided with synchros. The control device 5 comprises three actuators 13, 14 and 15 of hydraulic type and belonging to the first part 6. Each actuator 13 to 15 comprises a movable portion formed by a finger 13a to 15a. Each finger 13a to 15a is provided to cooperate with a control key of a fork. The finger 13a is in contact with a fork 16 mounted on an axis 17. The finger 14a drives a fork 18 mounted on an axis 19 and the finger 15a drives fork 20 also mounted on the axis 19.

Alternatively, it could be provided that the different forks are all mounted on different axes or all on the same axis. One could also design a control device provided with four linear actuators for the control of four forks, for example for a six-speed gearbox.

In this embodiment, each actuator is dedicated to a fork and the control only translation, which allows great mechanical simplicity of the assembly. In Figure 2, we see that the three actuators 13, 14 and 15 are aligned and parallel. To improve the architecture of the gearbox, it is possible to provide actuators arranged differently, slightly offset, with fingers of different length etc.

In Figure 3 is illustrated a slightly different embodiment in which only the first part 6 of the control device is shown. The first part 6 comprises three actuators 21, 22 and 23 arranged side by side in the same plane. The actuators 21 and 23 are linear while the actuator 22 is rotolinear. Each of the actuators 21, 22 and 23 is provided with a movable portion 21a, 22a, 23a comprising a rod 21b, 22b, 23b. The free end of each rod 21b, 22b, 23b supports two fingers 21c and 21d, 22d (the finger 22c is not visible), 23c and 23d. The pair of fingers 21c, 21d is provided for translational driving a sync actuating fork. It is the same for the pair of fingers 23c, 23d of the actuator 23. The movable portion 22a of the actuator 22 can be moved translationally and rotationally. The rotational movement allows to arrange the pair of fingers of the movable portion 22a on either side of a control portion of one of the forks 24, 25 or 26 associated. The displacement in translation makes it possible to move the selected range, <B> "</ B> the fork 24.

This type of control device is provided for a controllable synchro gearbox with two linear actuators for controlling the synchros and a rotolinear actuator for selecting and controlling the passage forks control the interconnection of the free mounted pinions on their axis with the said axis. The rotolinear actuator is formed by the assembly of a rotary actuator and a linear actuator.

Thanks to the invention, there is a gearbox control means directly attached to the box on a large opening thereof and with actuators acting directly on the passage forks and optionally declutching. One or more specific actuators may be provided to act on launcher / brake type synchros. We can therefore remove all the part of the internal control located in a conventional manner between the fork and the external actuator resulting in a gain in mass and speed of action. It avoids the use of complex drawing parts with many generators games and yield losses. Due to reduced energy losses, the controller may be less powerful than a conventional external control device, hence, again, mass gain and cost reduction.

Claims (2)

1. Control device (5) for a mechanical gearbox provided with a housing (1) and moving parts arranged in the housing, the control device comprising at least two actuators able to control the displacement of at least a part of said moving parts, characterized in that it comprises a means for closing off an opening provided in the casing of the gearbox, the shut-off means defining two parts of the control device, a first part (6) disposed on one side of the closure means and provided with elements for contact with at least a portion of said movable parts, and a second portion (7) disposed on the other side of the means for shutter and provided with elements intended to be connected to external bodies to the gearbox. 2. Device according to claim 1, characterized in that it comprises a frame provided with a flat surface (8) adapted to cooperate with a concordant surface (4) of the gearbox housing to seal. Device according to claim 1 or 2 characterized in that it comprises at least one control finger (10) and a rod (9) integral said finger, a first actuator being able to move the rod in translation, and a second actuator being able to move the rod in rotation, each finger being intended to actuate a fork of the gearbox. Device according to claim 3 characterized in that the first actuator is hydraulic. Device according to claim 3 or 4 characterized in that the second actuator is hydraulic. Device according to claim 3 or 4 characterized in that the second actuator is electric. Device according to claim 6 characterized in that the second actuator is a stepper motor equipped with a gear meshing with a corresponding toothing of said rod. 8. Device according to claim 1 or 2 characterized in that it comprises a plurality of control fingers (13a, 14a, 15a), each finger being integral with the movable portion of a linear actuator, so that each actuator is able to control a single fork of the gearbox. 9. Device according to one of the preceding claims characterized in that it comprises an additional actuator adapted to control a disengaging means integral with the gearbox. 10. Gearbox comprising a housing and a device according to any one of the preceding claims, the housing being provided with an opening (2) for receiving said device.