Transmission system for synchronizing a movement of an object mounted on at least two parallel slides

Abstract

The invention relates to a transmission system (1) for synchronizing a movement of an object mounted on at least two parallel slides, the system comprising: - at least two parallel slides (2A, 2B), each provided with a means (M) for actuating the slides by converting a rotational movement into a translational movement, - a drive pulley (3) mounted on a drive shaft intended to be connected to a drive means (5) capable of imparting a rotational movement to the drive shaft, - a first and a second receiver pulley (20A, 20B), each of said receiver pulleys being mounted on a receiver shaft connected to the means for actuating the slides, - a plurality of asynchronous belts (10, 10A, 10B) for transmitting a rotational movement between the drive pulley and the receiver pulleys, the drive pulley, the receiver pulleys and the asynchronous belts being arranged in a space lying between the two slides.

Description

Description TITLE: TRANSMISSION SYSTEM FOR SYNCHRONIZING THE MOVEMENT OF AN OBJECT MOUNTED ON AT LEAST TWO PARALLEL SLIDES Technical field of the invention

[0001] The present invention relates to a transmission system for synchronizing a movement of an object mounted on at least two parallel slides, the object possibly being a seat in the context of a seating application. Technological background

[0002] Traditionally, transmission systems allowing controlled movement, in particular, in translation of an object mounted on two slides use flexible hoses, chains or toothed (synchronous) belts.

[0003] However, these systems are rigid and do not provide complete satisfaction. Indeed, these types of systems do not allow shock absorption or avoid over-torque which can cause breakages or blockages of the transmission. These blockages can, in addition, lead to a desynchronization of the translational movement between the two parallel slides, that is to say that the movement of a given slide is carried out with an offset in relation to the other slide. Once the slides are misaligned with respect to each other, it is then difficult to realign them without human intervention.

[0004] Different systems exist, some of which are described by EP-A2-3 358 218.

[0005] In the particular case of transmission systems comprising chains or toothed belts, the meshing on the pulleys is a source of noise and vibrations which can be annoying for users.

[0006] Also, an objective of the invention is to propose an improved transmission system which makes it possible to resolve at least one of the aforementioned drawbacks.

[0007] Another objective of the invention is to propose a transmission system making it possible to improve the synchronization of the movement between two parallel slides. Summary of the invention

[0008] There is therefore proposed a transmission system for synchronizing a movement of an object mounted on at least two parallel slides, said system comprising: at least two parallel slides, each provided with a means for actuating the slides by converting a rotational movement into a translational movement, a driving pulley mounted on a motor shaft intended to be connected to a drive means capable of imparting a rotational movement to the motor shaft, a first and a second receiving pulleys, each of the receiving pulleys being mounted on a receiving shaft connected to the means for actuating the slides, a plurality of asynchronous belts for transmitting a rotational movement between the driving pulley and the receiving pulleys, the driving pulley, the receiving pulleys and the asynchronous belts being arranged in a space between the two slides.

[0009] Thus, thanks to the invention, an improvement in the synchronization of the movement of two slides is ensured. Indeed, the use of asynchronous belts, for example of the poly-V ® type, makes it possible to absorb any excess torque occurring on the transmission by slipping on the pulley. In this way, the desynchronization of one slide relative to the other is avoided. In other words, the invention makes it possible to protect the transmission against any torque anomaly. Furthermore, in the event of accidental desynchronization of the slides, the transmission system according to the invention allows the slides to be resynchronized relative to each other.

[0010] The transmission system according to the invention may comprise one or more of the following characteristics, taken in isolation from each other or in combination with each other: a first asynchronous belt is mounted between the driving pulley and the first receiving pulley and a second asynchronous belt is mounted between the driving pulley and the second receiving pulley; the system comprises an additional asynchronous belt and a reduction pulley, the reduction pulley comprising, on the same axis, a central wheel, having a given diameter, and two lateral shafts, each having a diameter smaller than the diameter of the central wheel so as to define a given ratio between the central wheel and each lateral shaft, the additional asynchronous belt being mounted between the driving pulley and the central wheel of the reduction pulley, a first asynchronous belt being mounted between the first receiving pulley and one of the two lateral shafts of the reduction pulley and a second asynchronous belt being mounted between the second receiving pulley and the other of the lateral shafts of the reduction pulley;the different pulleys are substantially aligned in a direction perpendicular to the direction of the slides; the system comprises a protective housing inside which the different pulleys and the different belts are mounted; the protective housing comprises orifices designed for the passage of the receiving shafts of each of the receiving pulleys so that the receiving shafts of the receiving pulleys are connected to the means for actuating the slides and another orifice designed for the passage of the motor shaft of the driving pulley so that the motor shaft of the driving pulley is connected to a drive means; the system comprises the drive means, for example an electric motor; the asynchronous belts of the plurality of asynchronous belts each comprise a plurality of longitudinal teeth.; Brief description of the figures

[0011] The invention will be better understood with the aid of the following description, given solely by way of example and with reference to the appended drawings in which:

[0012] Figure 1 represents a schematic view of an embodiment of a transmission system according to the invention,

[0013] Figure 2 represents a schematic view of another embodiment of a transmission system according to the invention,

[0014] Figure 3 represents a schematic view of an asynchronous belt, in particular of the poly-V ® type, mounted on a pulley,

[0015] Figure 4 represents a schematic view of a transmission system according to the invention comprising a protective housing, installed in particular for a seat application. Detailed description of the invention

[0016] With reference to Figures 1 and 2, the invention relates to a transmission system 1 for synchronizing a movement of an object mounted on at least two slides 2A, 2B. This transmission system 1 comprises at least two parallel slides 2A, 2B, a driving pulley 3, a first receiving pulley 20A, a second receiving pulley 20B and a plurality of asynchronous belts 10, 10A, 10B.

[0017] The slides 2A, 2B are each provided with a means M for actuating the slides 2A, 2B by converting a rotational movement into a translational movement. This means M may be a worm screw.

[0018] The drive pulley 3 is mounted on a motor shaft. This motor shaft is intended to be connected to a drive means 5 capable of imparting a rotational movement to the motor shaft. This drive means 5 allows the drive pulley 3 to be actuated and set into rotation. The drive pulley can, for example, be actuated by an electric motor or a mechanical means such as a wheel.

[0019] Each of the receiving pulleys 20A, 20B is mounted on a receiving shaft. This receiving shaft is connected to the means M for actuating the slides 2A, 2B.

[0020] The plurality of asynchronous belts 10, 10A, 10B is configured to transmit a rotational movement between the drive pulley 3 and the receiving pulleys 20A, 20B.

[0021] The driving pulley 3, the receiving pulleys 20A, 20B and the asynchronous belts 10, 10A, 10B are furthermore arranged in a space between the two slides 2A, 2B.

[0022] Figure 3 shows an example of an asynchronous belt A mounted on a pulley B. The asynchronous belt A is an example that can be used in the plurality of asynchronous belts 10, 10A, 10B. Similarly, the pulley B is an example that can be used for the different pulleys of the transmission system 1.

[0023] Typically, an asynchronous belt A has a plurality of longitudinal teeth D, the number of which varies depending on the desired characteristics. The asynchronous belt A may also have traction cords C embedded in its body. These traction cords C allow the tension of the belt A to be controlled when it is mounted between pulleys. Each asynchronous belt in the system may be of the poly-V ® type.

[0024] Still with reference to Figure 3, the pulley B has a plurality of grooves G designed to receive the longitudinal teeth D of the asynchronous belt A. The contact between the side walls of the longitudinal teeth D and the side walls of the grooves G makes it possible to ensure the drive of the pulley B.

[0025] Figure 1 shows a first embodiment according to the invention. In this first embodiment, the first asynchronous belt 10A is mounted between the driving pulley 3 and the first receiving pulley 20A while the second asynchronous belt 10B is mounted between the driving pulley 3 and the second receiving pulley 20B.

[0026] The rotating drive pulley 3 drives the rotation of the asynchronous belt 10A on the one hand and the asynchronous belt 10B on the other hand. It will be noted that the asynchronous belts 10A, 10B are driven in the same direction of rotation as the drive pulley 3. Each of the asynchronous belts 10A, 10B then drives in rotation a receiving pulley 20A, 20B which, via its receiving shaft, actuates the means M for actuating the slides 2A, 2B by converting the rotational movement into translational movement.

[0027] Figure 2 shows a second embodiment according to the invention. In this embodiment, the plurality of asynchronous belts comprises a first asynchronous belt 10A, a second asynchronous belt 10B and an additional asynchronous belt 10. The transmission system 1 further comprises a reduction pulley 4 comprising, on the same axis, a central wheel 41, having a given diameter, a first lateral shaft 42A and a second lateral shaft 42B, each having a diameter smaller than the diameter of the central wheel so as to define a given ratio between the central wheel and each lateral shaft 42A, 42B. It is understood that the first lateral shaft 42A and the second lateral shaft 42B each have an identical diameter.

[0028] The additional asynchronous belt 10 is mounted between the driving pulley 3 and the central wheel 41 of the reduction pulley 4. The first asynchronous belt 10A is mounted between the first receiving pulley 20A and the first lateral shaft 42A of the reduction pulley 4. The second asynchronous belt 10B is mounted between the second receiving pulley 20B and the second lateral shaft 42B of the reduction pulley 4.

[0029] The reduction pulley 4 makes it possible to redistribute a torque, provided by the additional asynchronous belt 10 from the driving pulley 3, to the asynchronous belts 10A, 10B via the lateral shafts 42A, 42B. The reduction pulley 4 comprising two lateral shafts 42A, 42B, the torque provided by the additional asynchronous belt 10 is thus divided by two between the asynchronous belts 10A, 10B. The diameter ratio between the central wheel 41 and the lateral shafts 42A, 42B makes it possible to compensate for the distribution of the torque received by the asynchronous belts 10A, 10B. The diameter ratio can be at least equal to 2.

[0030] In use, the aim is to optimize the drive means 5 actuating the drive pulley 3, that is to say, the best compromise is sought between the rotation speed and the torque delivered by the drive means 5, in particular when it is an electric motor. Furthermore, the rotation speed necessary for moving the object mounted on the slides 2A, 2B is generally a predetermined condition. In such a case, the drive ratio makes it possible to ensure that the drive means 5, such as a motor, will deliver the optimum torque over this speed range.

[0031] As previously, each of the asynchronous belts 10A, 10B then drives in rotation a receiving pulley 20A, 20B which, by via its receiving shaft, actuates the means M to actuate the slides 2A, 2B by converting the rotational movement into translational movement.

[0032] In a particular embodiment of Figure 2, the driving pulley 3 has a diameter of 11 mm, the receiving pulleys 20A, 20B and the lateral shafts 42A, 42B each have a diameter of 12.5 mm and the central pulley 41 has a diameter of 25 mm.

[0033] The asynchronous belts 10, 10A, 10B are, in this example, of the poly-V type with an H profile, and comprise polyamide traction cords. The first and second asynchronous belts 10A, 10B each comprise three longitudinal teeth. The additional asynchronous belt 10 comprises four longitudinal teeth.

[0034] In this configuration, the additional asynchronous belt 10 can transmit a torque substantially equal to 0.44 Nm to the reduction pulley 4 so that the torque transmitted by the first and second asynchronous belts 10A, 10B to the receiving pulleys 20A, 20B is substantially equal to 0.22 Nm.

[0035] In the embodiments of Figures 1 and 2, the different pulleys, i.e. the driving pulley 3, the receiving pulleys 20A, 20B and, where appropriate, the reducing pulley 4, are advantageously substantially aligned in a direction perpendicular to the direction of the slides 2A, 2B. This makes it possible to reduce the size of the transmission system 1.

[0036] Advantageously, the transmission system 1 according to the invention may comprise a protective housing 6 inside which the various pulleys and the various belts are mounted. This makes it possible to ensure protection of the pulleys and belts against external impacts which could destabilize the assembly.

[0037] The protective housing 6 may include orifices designed for the passage of the receiving shafts of each of the receiving pulleys 20A, 20B so that the receiving shafts of these pulleys are connected to the means M for actuating the slides 2A, 2B. The protective housing 6 may also include another orifice designed for the passage of the drive shaft of the pulley motor 3 such that this motor shaft is connected to a drive means 5, such as an electric motor.

[0038] The transmission system 1 may further comprise the drive means, for example an electric motor or a wheel intended to be turned manually.

[0039] In use, when an obstacle is located on the track of one of the slides, an over-torque occurs in the transmission system. Thus, thanks to the invention, the over-torque is absorbed by a slippage of the asynchronous belts on the pulleys. This allows a resynchronization of the slides with respect to each other.

[0040] With reference to Figure 4, the invention also relates to an assembly 100 comprising a seat 7 mounted on slides 2A, 2B of a transmission system 1 as described above. The seat 7 is for example a seat of a seat for a motor vehicle or for an aircraft.

[0041] In such an assembly 100, the transmission system 1 allows the movement of the seat 7 of the seat along the slides 2A, 2B while avoiding a blockage or misalignment of the latter.

[0042] The transmission system 1 as described above can be used, as seen previously, for a seat application but can also be used for any application currently using synchronous or smooth belts. These applications can be, for example, opening / closing mechanisms for sliding doors, windows, shutters or curtains.

[0043] Whatever the application envisaged, the use of an asynchronous belt, of the poly-V ® type for example, in a transmission system according to the invention, makes it possible to avoid desynchronization in the event of an impact and will provide a reduction in noise.

Claims

Claims [1] A transmission system (1) for synchronizing a movement of an object mounted on at least two parallel slides (2A, 2B), said system comprising: at least two parallel slides (2A, 2B), each provided with a means (M) for actuating the slides by converting a rotational movement into a translational movement, a driving pulley (3) mounted on a motor shaft intended to be connected to a drive means (5) capable of imparting a rotational movement to the motor shaft, a first and a second receiving pulley (20A, 20B), each of said receiving pulleys being mounted on a receiving shaft connected to said means (M) for actuating the slides, a plurality of asynchronous belts (10, 10A, 10B) for transmitting a rotational movement between the driving pulley and the receiving pulleys, the driving pulley, the receiving pulleys and the asynchronous belts being arranged in a space between the two slides. [2] System according to claim 1, wherein a first asynchronous belt (10A) is mounted between the driving pulley (3) and the first receiving pulley (20A) and a second asynchronous belt (10B) is mounted between the driving pulley (3) and the second receiving pulley (20B). [3] System (1) according to claim 1, comprising an additional asynchronous belt (10) and a reduction pulley (4), said reduction pulley comprising, on the same axis, a central wheel (41), having a given diameter, and two lateral shafts (42A, 42B), each having a diameter smaller than the diameter of the central wheel so as to define a given ratio between the central wheel and each lateral shaft, said additional asynchronous belt being mounted between the driving pulley (3) and said central wheel (41) of said reduction pulley (4), a first asynchronous belt (10A) being mounted between said first receiving pulley (20A) and one (42A) of the two lateral shafts of the reduction pulley [4] and a second asynchronous belt (10B) being mounted between said second receiving pulley (20B) and the other (42B) of said lateral shafts of the reduction pulley (4). [4] System (1) according to any one of claims 1 to 3, in which the different pulleys are substantially aligned in a direction perpendicular to the direction of the slides (2A, 2B). [5] System (1) according to any one of claims 1 to 4, comprising a protective housing (6) inside which the different pulleys and the different belts (10, 10A, 10B) are mounted. [6] System (1) according to claim 5, wherein said protective housing (6) comprises orifices designed for the passage of the receiving shafts of each of said receiving pulleys (20A, 20B) so that said receiving shafts of the receiving pulleys are connected to the means (M) for actuating the slides (2A, 2B) and another orifice designed for the passage of the motor shaft of said driving pulley (3) so that said motor shaft of the driving pulley is connected to a drive means (5). [7] System (1) according to any one of claims 1 to 6, further comprising said drive means (5), for example an electric motor. [8] System (1) according to any one of claims 1 to 7, wherein the asynchronous belts (10, 10A, 10B) of said plurality of asynchronous belts each comprise a plurality of longitudinal teeth (D).

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