FR2803358A1 - Gear change actuator for vehicle gearbox includes electronically controlled motor with threaded shaft displacing output actuator - Google Patents

Abstract

The device provides reversible action for moving gear selection components under electronic control. The control assembly for a robot-controlled gearbox comprises at least one actuator (A1) for shifting or selecting gears, and a power electronics unit for controlling the actuator. The actuator comprises an electric motor (M1) and a system (ST1) for transforming the rotation movement of the motor output shaft into a linear movement which is transmitted to an output element (T1). The movement transformation is achieved by a threaded shaft (10) which is driven via toothed wheels (12) by the motor, and a travelling element (15) running on the threaded shaft and fastened to the movement transmission device (DT1).

Description

The invention relates to a control unit for a robotised gearbox of a motor vehicle.

In general, such a control assembly comprises two actuators for passage and selection of gear ratios, and a power electronics control the two actuators.

 Each actuator comprises in particular an electric motor is controlled by the power electronics, and a system for transforming the rotational movement of the motor output shaft into a translation movement which is communicated by a device for transmitting motion to a component Transmission control.

According to US-A-4,440,035, the motion transformation system is constituted by a screw-nut assembly, the screw being coupled to the output shaft of the motor mounted parallel thereto, while the fixed nut in rotation but movable in translation is connected to the control element the gearbox.

The object of the invention is in particular to improve such actuators to increase the efficiency and make their operation very reversible, while having other advantages.

to this end, the invention proposes a control unit for a robotised gearbox of a motor vehicle, comprising at least one actuator for passage and / or selection of the gear ratios, and a power electronics for driving the actuator, said actuator comprising in particular an electric motor and a system for converting the rotational movement of the motor output shaft into a translation movement which is communicated by a motion transmission device to an output member of the actuator for controlling the gearbox, the motion transformation system comprising a threaded shaft coupled to the motor output shaft and a translatable member which is in contact with the threaded shaft and connected to the motion transmission device which includes a linkage elastic, control assembly which is characterized in that the motion transmission device of the rolling element at the output element of the actuator comprises an input element which is integral with the rolling element, and an output element guided in translation and integral with the output element of the actuator, the elastic connection being formed of a spring mounted in axial support between the input and output elements. The mounting of a single spring axially supported between all the input and output elements of the motion transmission device is more simple and less expensive than in the known art and makes the spring work under more favorable conditions, increasing thus its service life.

 Advantageously, the spring is supported at each of its ends on an axial portion of one of the input and output elements and on two parts symmetrical with respect to the axis of the spring of the other of the input elements and Release.

 This ensures the axial support of the spring at its ends on the input and output elements.

According to an exemplary embodiment of the invention, the thread of the shaft of the motion transformation system is at constant pitch, and the translational member which is in contact with the threaded shaft is a ball screw, a ball bushing or the like.

According to another exemplary embodiment of the invention, the threading of the shaft of the motion transformation system is at variable pitch.

Advantageously, the threading of the shaft of the motion transformation system has a larger pitch in its central part than towards its two ends, and the rolling element which is in contact with the threaded shaft is a rolling pin having a shape frustoconical, in roll or in ogive.

 The control assembly and its power electronics are supported by a casing comprising a body and a cover, said cover being advantageously used for fixing the casing inside the engine compartment of the vehicle. The actuator of the control assembly is associated with at least one position sensor which may be of the linear or rotary type.

 Advantageously, there is provided in the actuator a protection device to overcome a failure of the control electronics that would result in an absence of braking of the drive motor when the actuator reaches the end of the race, this protection device can be constituted by an absence of threading at each end of the shaft when the threading of the shaft is variable pitch, or by a torque limiter when the threading of the shaft is constant pitch.

The rotational support of the threaded shaft of the actuator can be provided by bearings or, more economically, by bearings which are associated with axial stops, the latter being able to be arranged to perform a function initial adjustment of the axial clearance of the threaded shaft, absorption of shocks and expansions, and / or recovery of axial forces with a minimum of friction.

In general - the drive motor shaft and the actuator threaded shaft are parallel to each other or axially aligned with each other, and - the input elements and output of the actuator motion transmission device extend parallel to the threaded shaft or are coaxially mounted to said shaft.

According to a first embodiment, the control assembly comprises two actuators for the selection and the passage of gear ratios, these two actuators having generally the same structure, that is to say with a system of transformation of rolling pin movement, and the drive shaft, the threaded shaft and the sliders of the actuator which extend parallel to each other.

According to a second embodiment, the control unit differs from the previous one in that the motion transformation system comprises a ball bushing.

According to a third embodiment, the two sliders of the actuator are mounted coaxially with the threaded shaft, which in particular makes it possible to reduce frictional forces.

According to a fourth embodiment, the control assembly comprises only one actuator whose output element forms a coninande shaft which is movable both in rotation and select the rank of the report to be engaged and in translation in order to engage the selected ratio, the rotational movement being obtained from a second motor.

control assembly according to the invention has many advantages, the main ones are listed below. use of a rolling member associated with the threaded shaft of the motion transformation system in each actuator makes it possible to optimize the operation of the associated motor and consequently the performance of the actuator.

use of a rolling member of the peg or roller type also makes it possible to have an asymmetrical assembly and to reduce the axis between the motor shaft and the threaded shaft of the movement transformation system, and this results in a bulk less than in the case of a ball bushing which is mounted coaxially to the threaded shaft.

 In addition, a rolling member of the peg or roller type can advantageously cooperate with a threaded shaft with variable pitch, while this step is necessarily fixed in the case of a ball bushing.

Moreover, the use of a threaded shaft with variable pitch, in particular a thread with small pitch towards both ends of the threaded shaft and a larger pitch in its central part, makes it possible to limit the power consumption required by the motor. to ensure that the actuator is maintained in the end position, in particular for the passage actuator. When the actuator is at the end of the stroke, it is the synchronization phase with the compressed elastic connection to have a maximum synchronization effort with a small pitch thread.

 In addition, the use of a peg or rolling roller is less sensitive to solid pollution than a bushing or ball screw, is simpler structure, easier assembly at a lower cost.

 Finally and in a general manner, a control assembly according to the invention with one or two actuators is designed taking into account a division of the various constituent elements according to those which can be considered as standard elements and those which are specific. of a given application depending on the type of vehicle for example.

 Indeed, the gearbox controls implement different operating principles (rotational rotates etc.), and it is difficult to design generic actuators.

The invention also aims to achieve this goal by providing a control assembly in which the actuator consists of at least one standard subassembly with a plastic housing, entry and exit slides which are guided in the housing, at least one position sensor of the sliders, a linear motion transformation system with a rolling element, and a single spring mounted in axial support between the two sliders, for example, and - elements or components specific to each application, as for example the motor including reducer, the power electronics which controls the actuator the output interface of the actuator, for example.

Other advantages, characteristics and details of the invention will emerge from the additional description which will follow with reference to the accompanying drawings, given solely by way of example and in which - Figure 1 is a partial perspective view of a control unit with two actuators according to a first embodiment of the invention, - Figure 2 is a cross-sectional view of the control assembly illustrated in Figure 1; - Figure 3 is a sectional view along the line III- FIG. 4 is a sectional view to illustrate a variant of a detail of FIG. 3; FIG. 5 is a diagrammatic sectional view to illustrate a variant of FIG. 3; FIGS. 6c are cross-sectional views for illustrating a mechanism for protecting the actuators; FIG. 7 is a sectional view for illustrating a torque limiter associated with the threaded shaft of the actuators; FIGS. 8a-88 are sectional views; to illustrate various arrangements of the threaded shaft of the actuators, - Figure 9 is a partial perspective view of a control assembly according to a second embodiment of the invention, - Figure 10 is a top view of the figure. 9, - Figure 11 is a sectional view along line XI-XI of Figure 10, - Figures 12 and 13 are two partial sectional views to illustrate two embodiments of the housing of the set of connnande, - the FIG. 14 is a partial sectional view of a third embodiment of the control assembly according to the invention, and FIGS. 15 and 16 are perspective views of a fourth embodiment of a set of control according to the invention.

 Reference is first made to FIGS. 1 to 3 which illustrate a first embodiment of a control assembly E for a motor vehicle automated gearbox.

This control unit E corrupts two actuators A1 and A2 of passage and selection of gear ratios. Each actuator A1 and A2 comprises in particular an electric motor M1 or M2, and a system ST1 or ST2 for transforming the rotational movement of the output shaft of the motor M1 or M2 into a translation movement which is communicated by a device DT1 or DT2 motion transmission to an output member of the associated actuator, such as a rod T1 or T2 to control the gearbox (not shown).

 Only the actuator A1 will be described below since, in this first embodiment, the actuator A2 is similar to the actuator A1.

The motion transformation system ST1 of the actuator A1 comprises a threaded shaft 10 which rotatably couples with the output shaft of the motor M1 by means of a gear train 12, and an element 15 (FIGS. ) which moves in translation and in rolling contact with the helical groove formed by the thread of the threaded shaft (10).

The device DT1 for movement transmission comprises an input slider 18 which is integral with the rolling element 15 of the motion transformation system ST1, an output slider 20 which is fixed to the output rod T1 of the actuator A1, and an elastic connection R or energy accumulation which is interposed between the two slides 18 and 20.

The axis X1-X1 of the motor M1, the threaded shaft 10 and the output shaft T1 of the actuator A1 extend parallel to each other.

 In general, the rolling element 15 which is in contact with the threaded shaft 10 may consist of either a screw or a ball bushing which can cooperate only with a threaded shaft 10 whose thread is not fixed, - either by a pin or roller roller which can advantageously cooperate with a threaded shaft 10 whose thread is fixed or variable.

In this first embodiment, the rolling element 15 is constituted by a pin P which, with reference to FIG. 3, is partially fitted into the inner race 22a of a bearing 22, the outer race 22b of which is secured to the slide of FIG. 18. The outer race 22b of the bearing 22 (FIG. 3) is fixed to the inlet slide 18. Thus, the rotation of the threaded shaft 10 causes the translational movement of the rolling pin P and the input slide 18 in a direction which is a function of the direction of rotation which is printed on the threaded shaft 10 by the motor M1. The pin P may be made of rolled metal, machined, sintered, molded, stamped or forged, the conically shaped head of which in FIGS. 2 and 3 may have a barrel shape, as illustrated alternatively in FIG. 4, or in the form of an ogive.

In FIGS. 2 3, the rolling pin P and the motor M1 are situated on either side of the threaded shaft 10. In a variant, as is schematically illustrated in FIG. 5, the rolling pin P can be located at above the threaded shaft 10. It is sufficient for this purpose to change the shape of the input slider 18 in a suitable manner. Thus, the use of a rolling pin P makes it possible to reduce the axle shaft 10-motor <B> mi </ B> and thus the size of the actuator, compared with the use of a ball bushing mounted coaxially with the threaded shaft 10.

The elastic connection R interposed between the two sliders 18 and 20 is constituted by a helical spring for example which can be prestressed and which bears axially at its ends on the sliders. In the embodiment of FIG. 2, the outlet slide 20 comprises, at each end of the spring R, a radial tab passing through the axis of the spring and on which the end turn of the spring rests in two zones. diametrically opposite, and the input slider 18 comprises two radial tabs symmetrical with respect to the axis of the spring and on which the said end turn of the spring rests.

 Referring to FIG. 3, one end of the output shaft T1 of the actuator A1 protrudes inside a blind hole 23 formed in the outlet slide 20, and is fixed to the slide 20 by a rotatable connection 24 located in the bottom of the hole 23, knowing that any other fastening means could be envisaged.

 When the motor Ml of the actuator A1 is turned on, the rotational movement of the threaded shaft 10 causes a simultaneous movement in translation of the rolling pin P and the input slider 18. If the output rod T1 of the A1 actuator is not subjected to any resistant force, the displacement of the input slider 18 drives that of the output slider 20 through the elastic connection R which undergoes no axial compression deformation. On the other hand, in the presence of a resisting force at the outlet rod T1, the displacement of the input slider 18 will cause the elastic connection R to be compressed axially without causing the slider 20 to move. this resisting force, which corresponds to the passage of the synchronization wall, the stored energy the elastic connection R is released, thereby causing the displacement of the output slide 20.

Threaded shaft 10 of the actuator A1 is coupled in rotation with the output shaft of the motor M1 by the gear train which comprises at least two spur gears or bevel gear possibly forming a speed reducer. The threaded shaft 10 rotatably supported by a ball bearing (FIG. 3) which makes it possible to ensure good recovery of the radial forces generated by the gears of the gear train 12 and also makes it possible to improve the efficiency. of the actuator A1.

In a general manner and with particular reference to FIG. 2, the control assembly E is partly housed a housing or casing 30 which consists of a body 30a and a cover 30b. The respective motors M1 and IM2 of the actuators A1 and A2 are mounted outside the body 30a of the housing 30, while the rest of the constituent elements of the actuators A1 and A2 is housed inside the body 30a. Advantageously, the body 30a of the casing 30 is generally split into two housings which respectively receive the two actuators A1 and A2. The power electronics EP which drives the two actuators A1 and A2, forms a subassembly is also supported by the housing, outside thereof.

Referring to Figures 1 and 2, the sliders and have grooves 32 extending parallel to the axis of the threaded shaft 10. These grooves receive corresponding ribs 33 which protrude from the inner face of the body 30a. housing 30 to support and guide the slides 18 and 20. When the actuator A1 is in operation, the motor M1 drives the input sliders 18 and output 20, and brakes end of stroke.

 However, in the case of an erroneous command provided the power electronics EP and which would not cause the engine M1 to stop, it is necessary to damp the shock of the actuator A1 when it comes to a stop on the housing 30. to not damage anything.

For this purpose, there is provided a mechanical protection device which will be explained below with reference to Figures 6a-6c.

The front and rear faces of the outlet slide 20, considering its direction of movement, have a part which projects from the corresponding front and rear faces of the input slide 18, this projection 20a forming a stop 20a (FIG. 6a). .

Thus, when the stop 20a of the output slide 20 comes into contact with the casing 30 (FIG. 6b), the motor M1 continues to rotate by driving in translation the input slide 18 but with concomitant axial compression of the elastic link R.

 However, the thread is interrupted at each end 10a of the threaded shaft 10 in order to disengage the motion transformation system ST1 while the motor M1 rotates. More specifically, the thread of the threaded shaft 10 is interrupted over a length such that the input slider 18 can not come into abutment on the housing 30 (FIG. 6c) even if the motor continues to rotate.

Finally, the deformation race of the elastic link R must be large enough so that it can then, after stopping the motor M1, reengage the rolling pin from the thread of the threaded shaft 10.

On the other hand, when the rolling element of the motion transformation system is constituted by a ball screw, it is not possible to interrupt the threading of the threaded shaft at each of its ends. In this case, it is possible to use a torque limiter, as shown in FIG. 7, which is calibrated at a torque greater than the maximum normal operating torque. This torque limiter 32 can be advantageously produced by means of a so-called tolerance ring which is mounted on the drive shaft or the drive shaft of the ball screw.

According to a more economical embodiment than ball bearings, the threaded shaft 10 can be rotatably supported by bearings such as cylindrical or swivel bearings, with the presence of axial contact stops of the sphere / plane type at the ends of the shaft. 10, as will be described below on various examples illustrated in Figures 8a-88.

In all these examples, the threaded shaft 10 is rotatably supported by rotatable bearings 33, knowing that the stops which make it possible to continuously compensate for the axial clearance of the threaded shaft 10 can be arranged with different arrangements depending on whether the it is also desired to have a device for initial adjustment of the axial clearance of the threaded shaft 10, an elastic device for absorbing shocks or expansions, and / or a device for taking up the axial forces with a minimum of friction. Indeed, all these devices can be combined with each other.

An assembly with an adjusting device D1 of the axial play of the threaded shaft is illustrated in FIG. 8a, with a variant illustrated in FIG. 8b.

In the exer # ple of Figure 8a, the axial stop B at each end of the threaded shaft 10 is constituted by two balls b1 and b2 steel and the same diameter which are housed in an axial blind hole 35 machined to the end of the threaded shaft 10, and by a set screw 37 of treated steel which can bear on the balls b1 and b2, knowing that the depth of the blind hole 35 which receives the balls is less than twice the diameter balls for making a contact of the sphere / plane type. Once the adjustment is made, the screw 37 is immobilized by gluing, for example. According to the variant of Figure 8b, the adjusting screw 37 is replaced by a washer 38 of treated steel which comes into contact with the balls, and by a resin plug 39 which, after solidification, bears on the washer 38. A mounting with a device D2 for absorbing shocks and expansions is illustrated in Figure 8c, with a variant shown in Figure 8d.

In the example of FIG. 8c, the axial stop B is formed by each end face of the threaded shaft 10 which is curved to obtain a contact of the sphere / plane type with a washer 38 of treated steel which is wedged to the By means of an elastomer stud 40. According to the variant of FIG. 8d, the washer 8 is of convex shape and the elastomer stud is removed.

An assembly with a device D3 for taking up the axial forces with a minimum of friction is illustrated in FIG. 8e, with two variants illustrated in FIGS. 8f and 8g.

In the example of FIG. 8e, the axial abutment B at each end of the threaded shaft 10 is constituted by a curved shape of the end face of the threaded shaft 10, and by a set screw 37 which is mounted as in the example of Figure 8a. According to the variant of Figure 8f, the curved faces of the end faces of the threaded shaft 10 are replaced by tips 41 reported in the form of T. Each end 41 has a stem 41a emuranched in a blind hole 42 machined at each end of the threaded shaft 10, and a domed head 41b which comes into contact with the adjusting screw 37. The tips 41 may be made of plastic or cold-stamped steel. According to the variant of FIG. 8g, the axial abutment B at each end of the threaded shaft 10 is constituted by two balls b1 and b2, as in the example of FIG. 8a, and by an elastomer stud 40 which replaces the set screw.

 In general, the two actuators A1 and A2 also comprise at least one position sensor which will be described later.

A second embodiment is illustrated in FIGS. 9-11, but the representation of the control assembly E has been deliberately limited to a single actuator, for example the actuator A1. In this second embodiment, the rolling element 15 which is associated with the threaded shaft 10 of the motion transformation system ST1 consists of a ball bushing D which involves a thread with a fixed pitch for the threaded shaft 10. This bushing D is mounted coaxially with the threaded shaft 10, and this results in a larger space requirement than in the case of the rolling pin P of the first embodiment.

This second embodiment makes it possible to illustrate another structure for the two slides 18 and 20 of the actuators and A2.

The inlet slider 18 associated with the ball bushing D is constituted by two stamped sheet metal parts 45 which are arranged parallel to one another and connected by columns 47, leaving between them an interior space (FIGS. 11). The posts 47 are fixed to the plates 45 by crimping, for example. The space between the two sheets 45 is generally split into two parts by means of a fixed inner partition 48 which extends parallel to the threaded shaft 10 of the motion transformation system ST1.

On the side adjacent to the motor M1, the two plates 45 each have an opening 50. These two openings 50 opposite one another delimit a housing which traps the ball bushing D.

On the side adjacent to the output rod T1 of the actuator, the two plates 45 delimit between them a housing inside which is mounted the outlet slide 20 which is in the form of a frame 55 having a central opening 57 The two sheets 45 of the input slider 18 each have an opening 59 located generally facing the opening 57 of the frame 55. These openings 57 and 59 form the housing of the spring R between the two sliders 18 and 20.

The output rod T1 of the actuator A1 is made integral with the frame 55 of the outlet slide 20 by fastening means 62. The rod T1 is in the form of a plate which extends parallel to the threaded shaft 10 and slides in a guide groove 68 formed in the housing 30.

In general, each actuator A1 and A2 is equipped with at least one position sensor which can be positioned either at the output shaft of the motor M1 or at the slides 18 and 20. In the mode embodiment shown in Figure 11, there are provided two sensors 70 which are respectively associated with the sliders 18 and 20 to give information on the position of the actuator or the gearbox, and the level of applied force.

These two sensors 70 comprise two contacts respectively carried by the two slides 18 and 20. These two contacts are situated on either side of the fixed partition 48 and respectively come into contact with two conducting tracks carried on the partition 48.

The sensors 70 shown in FIG. 11 are linear type but, alternatively, rotary type sensors could be used.

As for the first embodiment, the control assembly E is supported by a housing 30 with the motors M1 M2 located outside the housing, while the other components of the actuators A1 and A2 are housed inside. fixed partition casing 48 which is located between the two plates 45 of the input slider 18 is integral with the housing 30 and means guiding shape of the sliders 18 and 20.

Of course, in this second embodiment, could replace the ball bushing D by a rolling pin P and adapt accordingly the structure of the input slider 18.

FIGS. 12 and 13 illustrate an embodiment of the housing 30 which supports the code set E, this example being applicable to the two embodiments described above. In general, the housing 30 is fixed to the interior of the engine compartment of the vehicle, this fixing can be performed at its body 30a or its cover 30b.

In Figure 12, the housing 30 is fixed at its body 30a by means of screws or bolts through holes 30c drilled in a peripheral rim of the body 30a. By cons, in Figure 10, the fixing of the housing 30 is formed at its lid 30b which have holes 30c pierced in a peripheral rim of the lid 30b. Providing the fixing points of the housing 30 at its cover 30b, has the advantage of allowing an interchangeability of said cover according to the different vehicles while maintaining the same housing body.

 In Figure 14, there is schematically illustrated a third embodiment of the control assembly E according to the invention.

This third embodiment essentially differs from the two modes described above by the fact that the set of connectors represented comprises only one actuator A1 and that the two slides 18 and 20 are coaxially mounted on the threaded shaft 10. rolling element 15 which cooperates with the threaded shaft 10 is a ball bushing D in the illustrated example. This third embodiment makes it possible in particular to reduce the friction forces during the displacement of the sliders, which results in a better efficiency of the actuator, and makes it possible to obtain a more compact assembly.

The input slider 18 is in the form of a sleeve 80 in which the threaded shaft 10 engages, which cooperates with a screw socket D integral with the sleeve 80. The outer periphery of the sleeve 80 has two shoulders 82 and 84 which delimit between them a peripheral groove 86.

Two washers 88 are attached around the sleeve 80 and a spring R, so that the spring comes to be housed in the groove 86 by resting on the two washers 88 which are respectively wedged, under the spring preload, against the two shoulders 82 and 84 which delimit the peripheral groove 86. The washers 88 are slotted so as to be mounted in the groove 86 of the sleeve 80. The washers 88 have an outer diameter greater than that of the shoulders 82 and 84.

The outlet slide 20 is also in the form of a sleeve 90 which is mounted coaxially with the sleeve 80. The sleeve 90 has a peripheral radially inner shoulder 92 at one end while the output rod T1 of the actuator A1 is a tubular element which engages inside the sleeve 90 on the side opposite to the shoulder 92.

The assembly is carried out so that the shoulder 92 of the sleeve 90 and the inner end of the output rod T1 respectively come into contact with the two washers When the sleeve D moves to the left, shoulder 82 of the sleeve 80 of the input slider 18 drives output member T1 of the actuator A1 via the spring R which bears on said output member T1, or compresses the spring R without driving the output rod T1 when the latter offers a resistant effort that opposes its displacement.

the sleeve D moves to the right, it is the shoulder 84 of the sleeve 80 which drives the outlet slide 20 by means of the spring which bears on the shoulder 92 of the sleeve 90.

As a variant of this third embodiment, the drive shaft of the actuator and the threaded shaft of the motion transformation system could be axially aligned with each other by taking up generally the structure of the first, second or third embodiment.

 A fourth embodiment of a control assembly E with a single actuator A or integrated actuator will be described hereinafter with reference to FIGS. 15 and 16, which will make it possible to directly control the movement of the players of the gearbox.

 The output rod T of the actuator A constitutes a single output shaft that is both movable in translation and in rotation to control the gearbox butts, knowing that the rotational movement will be used to perform selecting the rank of the report to engage, then the translational movement will be used to engage the selected report.

In general, the translational movement of the output shaft T of the actuator A is ensured in a manner analogous to the actuators described above, namely: an electric motor M, a gearbox 12 with straight teeth, a a motion transformation system with a ball bushing which is mounted coaxially around the threaded shaft 10 rotatably driving the motor M, an input slider 18 and an output slider 20 with the interposition of a spring, the shaft output T of the actuator A being mounted axially integral in a housing L of the output slide 20 but being free to rotate.

The rotational movement of the output shaft of the actuator A is obtained from - a second electric motor M ', and - a gear 12' with epicyclic gear, for example rotatably coupled to the shaft of the second electric motor M ', while 1 output shaft 100 of the gear 12' is mounted fixed in translation but rotatably connected to the output shaft T of the actuator A which is in its axial extension.

This results in the presence of a coupling device 101 between the output shaft 100 of the gearbox and the output shaft T of the actuator A, which allows telescopic movement between these two shafts. Such a coupling can be achieved by means of splines, or a pin penetrating into an oblong shaped light, for example.

Advantageously, in order to be able to perform a preselection of the selection range of the chosen ratio, a resilient rotary link is introduced with curved or preloaded straight springs, mounted in a cassette for example, between the movable ring gear 102 of the epicyclic gear train of the gearbox 12 'and its drive shaft. exit 100.

A passage finger 104 is secured to the output shaft T of the actuator A and is intended to cooperate with one of a set of brackets 106 of the gearbox which are arranged in the example described. , radially. Alternatively, the brackets 106 could be arranged in parallel being superimposed on top of each other, as in the case of a traditional gearbox, knowing then that they must be arranged so as to always have a portion that can be actuated by the passage finger 104 in its rotational movement.

Such an actuator A eliminates all the internal control which is located between the external shafts and the finger passage of the butts in the gearbox, including the return springs in selection which are responsible for maintaining this finger in the rank of the 3àle and 4th reports. However, these springs also allow in a traditional gearbox to catch the noise from the shocks of the control finger against the sticks, when the assembly is particularly subject to vibratory modes of transmission.

Also, to ensure this function in the actuator according to the invention, it is advantageous to report a blasting 110 on the epicyclic gear reducer 12 ', this blasting 110 ensuring a holding function in angular position, with indexing, corresponding to the rows of possible ratios of the gearbox. The blasting 110 can thus prevent the passage finger 104 from clashing with other butts or deflecting the desired position.

 Alternatively, the blasting 110 could be mounted in the gearbox so as to overcome manufacturing tolerances and mounting positioning, and also reduce the size of the actuator.

 A locking device of the sticks 106 is also to be provided, this device can be mounted in the gearbox control fork, for example, and be constituted by a locking said "ball and man", disk, ...

 Finally, it is desirable to have a torque limiter in each transmission kinematic transmission chain (passage and gear selection) and this, in order to optimally optimize the dimensioning of the various components of the actuator and ensure their non-destruction during extreme operating conditions.

Claims (47)

1. set of conynande for robotized gearbox of a motor vehicle, comprising at least one actuator (A, A1, A2) for passage and / or selection of gear ratios, and a power electronics (EP) for driving the actuator (A, A1, A2), said actuator including including an electric motor (M, M1, 1,12) and a system <B> (ST, </ B> ST1, ST2) for transforming the rotational movement the output shaft of the motor in a translation movement which is communicated by a motion transmission device (DT, DT1, DT2) to an output member (T1, T2) of the actuator for controlling the gearbox the motion transformation system (ST1, ST2) comprising a threaded shaft (10) coupled to the motor output shaft (M1), and at least one movable member (15) in translation which is in contact with the threaded shaft (10) and is connected to the motion transmission device (DT, DT1, DT2) which includes a linkage elastic device (R), characterized in that the motion transmission device (DT, DT1, DT2) comprises an input member (18) and an output member (20) guided in translation, that the input element (18) is integral with the movable element (15) of the motion transformation system (ST, ST1, ST2), in that the output element (20) integral with the element output (T1, T2) of the actuator, and in that the elastic connection is formed of a spring (R) mounted in axial support between the input and output elements (18, 20). 2. conriande assembly according to claim 1, characterized in that the spring (R) is supported at each of its ends on an axial portion of one of the input and output elements (18, 20) and on parts symmetrical with respect to the axis of the spring (R) of the other of the input and output elements (18, 2 3. Control assembly according to claim 1 or 2, characterized in that the threading of the threaded shaft (10) of the motion transformation system (ST, ST1, ST2) is at a constant pitch, and in that the movable member (15) in contact with the threaded shaft (10) is a ball screw, a ball bushing or the like. 4. Control assembly according to claim 1 or 2, characterized in that the threading of the threaded shaft (10) of the motion transformation system (ST, ST1, ST2) is not variable. 5. Control assembly according to claim 4, characterized in that the threading of the threaded shaft (10) of the system (ST1, ST2) of motion transformation has a wider pitch in its central part than towards its two ends. 6. Control assembly according to claim 5, characterized in that the thread is removed at each end of the threaded shaft (10). 7. Control assembly according to any one of claims 4 to 6, characterized in that the movable member (15) in contact with the threaded shaft (10) is a rolling pin (P), a roller or the like . 8. Control assembly according to claim 7, characterized in that the movable member (15) in contact with the threaded shaft (10) is a rolling pin (P) having a frustoconical shape, roll or ogive. 9. Control assembly according to claim 8, characterized in that the rolling pin (P) is engaged in the inner race (20a) or in the outer race (20b) of a bearing (20). 10. Control assembly according to claim 8, characterized in that the rolling pin (P) is formed by the inner race (20a) or the outer race (20b) of a bearing (20). 11. Control assembly according to any one of the preceding claims characterized in that the threaded shaft (10) of the system (ST, STI, ST2) of motion transformation is supported at each of its ends by a bearing (25) . 12. Control assembly according to any one of claims 1 to 10, characterized in that the threaded shaft (10) of the system (ST, ST1, ST2) of motion transformation is supported at each of its ends by a bearing (33) which is associated with an axial stop (B). 13. conynande assembly according to claim 12, characterized in that the axial abutment (B) is constituted by two balls (b1, b2) which are housed in an axial blind hole (35) machined the end of the threaded shaft (10), and by a set screw (37) which bears on the balls (b1, b2), to form a device for adjusting the axial clearance of the threaded shaft (10). 14. Control assembly according to claim 12, characterized in that the axial abutment (B) consists of two balls (b1, b2) which are housed in an axial blind hole (35) machined at the end of the shaft. threaded (10), by a washer (38) which comes into contact with the balls (b1, b2), and by a resin plug (39) which bears on the washer (38), to form a device for adjusting the game axial position of the threaded shaft (10). 15. Control assembly according to claim 12, characterized in that the axial stop (B) is constituted by the convex end face of the threaded shaft (10), and by a washer (38) which is wedged by means an elastomeric pad (40), forming a shock absorbing device and expansions. 16. Control assembly according to claim 12, characterized in that the axial stop (B) is constituted by the convex end face of the threaded shaft (10) and by a set screw (37), to form a device for taking up axial forces with a minimum of friction. 17. Control assembly according to claim 12, characterized in that the axial stop (B) is constituted by a tip (41) mounted in a blind hole (42) machined at each end of the threaded shaft (10), tip (41) having a domed head (41b), and a set screw (37) which bears on said head (41b), to form a device for taking up axial forces with a minimum of friction. 18. Control assembly according to one of claims 1 to 17, characterized in that the output element (T1, T2) of the actuator (A, A1, A2) is constituted by a rod fixed by a pivoted connection (24). ) to the output slide (20). 19. Control assembly according to one of claims 1 to 18, characterized in that the input element (18) consists of two metal sheets (45) stamped, parallel and spaced from each other by small columns (47). 20. Control assembly according to claim 19, characterized in that an interior space delimited between the two sheets) allows the guiding of the input and output elements (18,20) along a fixed partition (48) which extends parallel to the threaded shaft (10). 21. Conynande assembly according to any one of the preceding claims, characterized in that it comprises at least one position sensor (70) which is associated with the input and output elements (18,20) or the motor (M , M1, M2) of the actuator (A, A1, A2). 22. Control assembly according to claim 21, characterized in that the position sensor (70) is of the linear rotary type. 23. Control assembly according to claim 22, characterized in that the sensor (70) is of the linear type and comprises a contact (70a) carried by the input element (18), and a conductive track (70b) s' extending along a fixed partition (48). 24. Control assembly according to any one of the preceding claims, characterized in that it is supported by a housing (30) consisting of a body (30a) and a cover (30b), in that the motor The actuator (A, A1, A2) is mounted outside the housing (30), and link (DT, DT1, DT2) are housed inside the housing (30). 25. Control assembly according to claim 24, characterized in that the power electronics (EP) which drives the actuator (A, A1, A2) is supported by the housing (30). 26. Control assembly according to claim 24 or 25, characterized in that the housing (30) is fixed inside the engine bonnet of the vehicle at its body (30a). 27. Control assembly according to claim 24 or 25, characterized in that the housing (30) is fixed inside the engine bonnet of the vehicle at its cover (30b). 28. Control assembly according to any one of claims 24 to 27, characterized in that the housing (30) is made of a rigid plastic material. Control assembly according to any one of claims 6 to 28, characterized in that the thread is removed at each end of the threaded shaft (10) over a length such that the system (ST, ST1, ST2) of motion transformation is disengaged if the motor (M, M1, M2) continues to rotate. Control assembly according to claim 29, characterized in that, prior to the disengagement of the motion transformation system (ST, ST1, ST2), the electrical connection (R) is sufficiently compressed to reengage the rolling pin (in the thread of the threaded shaft (10). 31. Control assembly according to any one of claims 1 to 28, characterized in that the actuator (A, A1, A2) also comprises a torque limiter (32) which is calibrated at a torque greater than the maximum torque of normal operation of the actuator. 32. Couré-ande assembly according to claim 31, characterized in that the torque limiter (32) is produced by means of a so-called tolerance ring mounted on the drive shaft of the threaded shaft (10). Control unit according to one of Claims 1 to 32, characterized in that the input and output elements (18, 20) of the motion transmission device (DT, DT1, DT2) are mounted in parallel to each other. the threaded shaft (10) of the motion transformation system (ST, ST1, ST2). Control assembly according to one of claims 1 to 32, characterized in that the input and output elements (18, 20) of the motion transmission device (DT, DT1, DT2) are coaxially mounted to the threaded shaft (10) of the motion transformation system (ST, ST1, ST2). 35. Control assembly according to any one of claims 1 to 34, characterized in that the motor shaft (M, M1, M2) and the threaded shaft (10) of the actuator are mounted parallel to one another. to the other. 36. Control assembly according to any one of claims 1 to 34, characterized in that the drive shaft (M, M1, M2) and the threaded shaft (10) of the actuator are axially aligned with each other. the other. 37. FYis command assembly according to any one of the preceding claims, characterized in that it comprises two actuators (Al, A2) for selection and shift gear ratio. 38. Control assembly according to claim 37, characterized in that the two actuators (A1, A2) are supported by a same housing (30) of plastic. 39. Control assembly according to any one of the preceding claims, characterized in that it comprises a single actuator (A) whose output element (T) constitutes an output shaft both rotatable to select the rank of the report to engage and mobile in translation to engage the selected report. 40. Control assembly according to claim 39, characterized in that the rotational movement of one actuator (A) is obtained from a second electric motor (M ') with the interposition of a gear reducer (12'). epicyclic. 41. A control assembly according to claim 40, characterized in that the output shaft (100) of the gearbox (12) and the output shaft (T) of the actuator (A) are coupled to each other. other telescopically. 42. Control assembly according to claim 40 or 41, characterized in that a rotatable elastic connection is interposed between the ring (102) of the planetary gear train of the gearbox (12 ') and the output shaft (100). 43. Control assembly according to any one of claims 39 to 42, characterized in that a passage finger (104) is integral with the output shaft (T) of the actuator and intended to cooperate with the one of a set of sticks (106). 44. Control assembly according to claim 43, characterized in that it also comprises a device (110) for maintaining the angular position of the passage finger (104). 45. Control assembly according to claim 44, characterized in that the holding device (110) is constituted by a blasting. 46. Control assembly according to claim 44 or 45, characterized in that the holding device 110) is mounted on the actuator (A) or in the gearbox. 47. Control assembly according to any one of claims 43 to 46, characterized in that it comprises a locking device of the butts (106).