SEAT

Abstract

A seat (1) is provided with a reclining mechanism in which the angle of a backrest (5) is adjustable. The seat (1) comprises a reclining device (7) for changing the angle of a backrest (5), wherein the reclining device (7) has an internal toothed gear (7B), an external toothed gear (7A), a key (7C, 7D) and a counter plate (7E), an electric motor (9) that generates a driving force for driving the counter plate (7E), and a control unit (10) for controlling the operation of the electric motor (9), wherein the control unit (10) can perform a rotation reversal control, wherein, if the direction of rotation of the electric motor (9) is considered the direction of actuation when changing the angle of the backrest (5) and the direction opposite to the direction of actuation is considered the reversal direction, the rotation reversal control is a control that is performed after the electric motor (9) has rotated in the direction of actuation.wherein, when executing the rotation reversal control within a range in which the angle of the backrest (5) does not change, the control unit causes the electric motor (9) to rotate in the reverse direction.

Description

background

[0001] The present disclosure relates to a seat with a reclining mechanism in which the angle of a backrest is changeable.

[0002] In an invention disclosed in JP 2020-125072 A, backlash arising on a toothed part between an output gear and a toothed segment is eliminated by causing a reverse rotation of an electric motor when a backrest is fixed by a locking device. Brief description

[0003] In a back-folding device with a wobble mechanism comprising an internal gear, an external gear, a wedge (also referred to as a wedge section) and a counter plate, the part where the wedge and the counter plate come into contact when the electric motor rotates forward (hereinafter referred to as the first contact section) and the part where the wedge and the counter plate come into contact when the electric motor rotates backward (hereinafter referred to as the second contact section) are different.

[0004] When the electric motor rotates forward, the first contact section is in contact, but the second contact section is not, resulting in a gap. Conversely, when the electric motor rotates backward, the second contact section is in contact, but the first contact section is not, resulting in a gap.

[0005] During the reversal of rotation from forward to reverse rotation of the electric motor and from reverse to forward rotation of the electric motor, a collision occurs at the contact section of the counter plate and the wedge, which were separated from each other until the reversal of rotation.

[0006] When the electric motor reverses its rotation, the impact shock is transmitted to the occupant, which the occupant may find unpleasant. In light of this, the present disclosure discloses a seat that can mitigate this shock.

[0007] A seat with a reclining mechanism in which the angle of the backrest can be changed preferably comprises, for example, at least one of the following design elements.

[0008] The design elements comprise a folding mechanism (7) for changing the angle of a backrest, wherein the folding mechanism (7) has an internal toothed gear (7B), an external toothed gear (7A), a wedge (7C, 7D) and a counter plate (7E), an electric motor (9) which generates a driving force for rotating the counter plate (7E), and a control unit (10) for controlling the operation of the electric motor (9), wherein the control unit (10) can perform a rotation reversal control.

[0009] The rotation reversal control is a control that is executed after the electric motor (9) has been rotated in an actuation direction, wherein the control unit (10) preferably causes the electric motor (9) to rotate in the opposite direction when the rotation reversal control is executed within a range in which the angle of the backrest does not change. The reverse direction is the opposite direction to the actuation direction. The actuation direction is the direction of rotation of the electric motor (9) when the angle of the backrest is changed.

[0010] When the electric motor (9) switches from forward to reverse rotation, the gap between the wedge (7C, 7D) and the counter plate (7E) has already closed at the seat. Consequently, when the electric motor (9) reverses its rotation, there is no impact between the counter plate (7E) and the wedge (7C, 7D). Since the vibration is thus reduced, any unpleasant sensation for the occupant can be prevented.

[0011] If a generated torque of the electric motor (9) required to change the angle of the backrest is defined as the lifting torque, the control unit (10) preferably controls the torque generated at the electric motor (9) when performing the rotation reversal control so that it is below the lifting torque.

[0012] The control unit (10) can perform an automatic control by which the angle of the backrest is brought to a predetermined angle, wherein the control unit (10) preferably performs the rotation reversal control after the automatic control.

[0013] The control unit (10) preferably performs a control to stop the excitation before the start of the rotation reversal control, in which it stops the power supply to the electric motor (9). This allows the rotation reversal control to be carried out after the electric motor (9) has come to a complete standstill.

[0014] Furthermore, the control unit (10) preferably executes the automatic control, the excitation stop control, and the rotation reversal control sequentially in a single operating sequence. This prevents any other control operation, such as an interrupt control or the like, from being carried out during the execution of the operating sequence.

[0015] It should be noted that the reference numerals given above in parentheses are an example to clarify the correspondences to the specific embodiments etc. of the embodiment discussed below, and that the present disclosure is not limited to the specific embodiments etc. indicated by these in parentheses. Brief description of the characters

[0016] Together with the figures, an example of an embodiment of the present object will now be described. Fig. Figure 1 is a view of a vehicle seat according to one embodiment. Fig. Figure 2 is an expanded view of a back flap device according to the embodiment. Fig. Figure 3 is a block diagram illustrating a control system of an electric motor according to the embodiment. Fig. Figure 4 is a diagram illustrating the control of the electric motor according to the embodiment. Fig. Figure 5 is a view illustrating the back-folding mechanism according to the embodiment during forward rotation. Fig. Figure 6 is a view illustrating the back-folding mechanism according to the embodiment during reverse rotation. embodiment of the invention

[0017] The following embodiment of the invention shows an example of an embodiment that falls within the technical scope of the present disclosure. The inventive elements specified within the scope of the claims are therefore not limited to the specific design and structure shown in the following embodiment.

[0018] In the present embodiment, the example of a vehicle seat installed in a vehicle such as a car or the like is described. Unless a referenced and described element or part is expressly specified as "a single" element or part, at least one element or part is provided.

[0019] This means that unless an element or part is expressly specified as "a single" element or part, two or more elements or parts may be provided. The vehicle seat shown in the present disclosure comprises at least the elements or parts identified by reference numerals and described, and at least one of the structural parts shown in the figures. 1. Overview of the vehicle seat

[0020] As in Fig. As shown in Figure 1, the vehicle seat 1 comprises at least one seat cushion 3 and a backrest 5. The seat cushion 3 is a component for supporting the buttocks of an occupant. The seat cushion 3 includes, among other things, a frame (not shown).

[0021] The upholstery frame is an element that forms the framework of the seat cushion 3. The backrest 5 is a component for supporting the occupant's back. The backrest 5 includes, among other things, a backrest frame 5A.

[0022] The backrest frame 5A is an element that forms the framework of the backrest 5 and includes, among other things, two side frames 5B, 5C, and two coupling elements 5D, 5E. The side frame 5B is an element that is arranged on one end of the backrest 5 in the direction of seat width and extends in a top-bottom direction.

[0023] The side frame 5C is an element located on the opposite end of the backrest 5 (in the direction of seat width) and extends in a top-bottom direction. The coupling element 5D extends in the direction of seat width and couples the side frames 5B and 5C to each other at their upper end. The coupling element 5E extends in the direction of seat width and couples the side frames 5B and 5C to each other at their lower end.

[0024] The backrest frame 5A is coupled to the upholstery frame via a folding mechanism 7. The vehicle seat 1 is therefore a seat with a folding mechanism, in which the angle of the backrest 5 relative to the seat cushion 3 can be changed.

[0025] The vehicle seat 1 comprises two folding mechanisms 7. The first folding mechanism 7 couples the side frame 5B and the upholstery frame to each other. The second folding mechanism 7 couples the side frame 5C and the upholstery frame to each other.

[0026] The two folding devices 7 have the same structure. The folding devices 7 are each a folding device of the wobble mechanism type and, as shown in Fig. Figure 2 shows, among other things, an external gear 7A, an internal gear 7B, keys 7C, 7D, a counter plate 7E, a spring 7F and a ring cover 7G.

[0027] The external gear 7A rotates in a circular motion, meshing with the internal gear 7B. Since the number of teeth on the external gear 7A is less than the number of teeth on the internal gear 7B, the external gear 7A and the internal gear 7B shift relative to each other as the internal gear 7B rotates.

[0028] The counter plate 7E drives the external gear 7A. The counter plate 7E is driven by the electric motor 9 (see Fig. 1) driven. The driving force of the electric motor 9 is transmitted via a drive shaft 9A (see Fig. 1) transferred to the two back flap devices 7.

[0029] When the electric motor 9 is operated, the angle of the backrest 5 changes in relation to the seat cushion 3. The direction of rotation of the electric motor 9 when changing the angle of the backrest 5 is referred to below as the direction of operation, while the direction opposite to the direction of operation is referred to as the reversal direction.

[0030] If the direction of operation is forward rotation, then the reversal direction is reverse rotation. If the direction of operation is reverse rotation, then the reversal direction is forward rotation. 2. Control of the operation of the electric motor 2.1 Overview of the control system

[0031] In addition to the design elements listed above, vehicle seat 1 includes, as in Fig. Figure 3 shows at least one control unit 10, one mode selector switch 11 and one position sensor 12. The control unit 10 is a controller for controlling the operation of the electric motor 9.

[0032] The control unit 10 is a microcomputer-type controller comprising at least a CPU, ROM, and RAM. The software for executing the automatic control, the excitation stop control, and the rotation reversal control, described below, is stored in a non-volatile memory unit such as ROM or the like.

[0033] The mode selection switch 11 is an operating element that is operated by a user of the vehicle seat 1. By operating the mode selection switch 11, the user can set the position of the vehicle seat 1 (in the present embodiment, the angle of the backrest 5) to a predefined mode.

[0034] The predefined modes are a driving mode and a rest mode. The driving mode is a mode in which the angle of the backrest 5 is at an angle suitable for driving the vehicle.

[0035] In rest mode, the angle of the backrest 5 is greater than in driving mode, and it is a mode with the backrest 5 reclined far back. The angle of the backrest 5 in each mode is a user-defined angle. This set angle is stored in the non-volatile memory of the control unit 10.

[0036] The position sensor 12 detects the position of the counter plate 7E directly or indirectly. The detection signal of the position sensor 12 and the signal of the mode selector switch 11 are fed into the control unit 10. Details of the electric motor control

[0037] When one of the driving modes or the rest mode is selected, the control unit 10 performs as described in Fig. Figure 4 shows an operating sequence in which the automatic control, the excitation stop control, and the rotation reversal control follow one another, executing the sequence corresponding to the selected mode. The execution of the sequence corresponding to the selected mode is also referred to as "mode playback." Automatic control

[0038] The automatic control is a control system for adjusting the angle of the backrest 5 to an angle corresponding to the selected mode. Specifically, if, for example, the rest mode is selected, the control unit 10 uses the reading from the position sensor 12 to detect the current angle of the backrest 5, activates the electric motor, and adjusts the angle of the backrest 5 to the angle required for rest mode. Rotation reversal control

[0039] The rotation reversal control is executed after the electric motor 9 has rotated in the direction of operation, i.e., after the automatic control has been carried out. During the rotation reversal control, the control unit 10 rotates the electric motor 9 in the reverse direction within a range where the angle of the backrest 5 does not change.

[0040] When executing the rotation reversal control, the control unit 10 regulates the torque generated by the electric motor 9 so that it is below a cancellation torque. The cancellation torque refers to the torque generated by the electric motor 9 that is required to change the angle of the backrest 5.

[0041] The control unit 10 controls the torque generated by the electric motor 9 by means of a duty cycle control, in which it controls the excitation ratio of the electric motor 9. Specifically, the duty cycle during the reversing control is a smaller value than the duty cycle at the end of the automatic control. Control to stop the excitation

[0042] The excitation stop control is a control that is executed before the rotation reversal control and stops the excitation of the electric motor 9. Specifically, the control unit 10 executes the rotation reversal control after the excitation of the electric motor 9 has been stopped for a predetermined time following the completion of the automatic control.

[0043] Due to the rotating mechanical components and the inertia of the electric motor 9, etc., the counter plate 7E does not stop immediately even after the excitation of the electric motor 9 is stopped. The execution time of the control for stopping the excitation (in other words, the duration for which the excitation is stopped) is therefore the time required until the counter plate 7E comes to a complete stop.

[0044] 3. Features of the vehicle seat of the present embodiment When the electric motor 9 rotates forward, the wedge 7D and the counter plate 7E come into contact with each other at a point 7E1, as shown in Fig. 5 shown. When the electric motor 9 rotates backwards, the wedge 7C and the counter plate 7E come into contact with each other at a point 7E2, as shown in Fig. 6 shown.

[0045] When the electric motor 9 rotates forward, the wedge 7D and the counter plate 7E are in contact, while a gap G1 is created between the wedge 7C and the counter plate 7E, as shown in Fig. 5 shown. When the electric motor 9 rotates backwards, the wedge 7C and the counter plate 7E are in contact, while a gap G2 is formed between the wedge 7D and the counter plate 7E, as shown in Fig. 6 shown.

[0046] During the reversal of rotation from forward rotation to reverse rotation of the electric motor 9 and from reverse rotation to forward rotation of the electric motor 9, a collision therefore occurs in a typical vehicle seat at the contact section of the counter plate 7E and the wedge 7C, 7D, which were separated from each other by the gap G1, G2 until the reversal of rotation.

[0047] However, since the control unit 10 causes the electric motor 9 to rotate in the reverse direction after the automatic control has been carried out in an area in which the angle of the backrest 5 does not change, the gap between the wedge 7C, 7D and the counter plate 7E disappears at the end of the rest mode or driving mode.

[0048] Specifically, if, for example, the forward rotation of the counter plate 7E stops, the control unit 10 causes the counter plate 7E to rotate in the opposite direction, thus eliminating the gap G1 that formed during the forward rotation. Consequently, during the next reverse rotation of the electric motor 9, there is no impact between the counter plate 7E and the wedge 7C.

[0049] Since the control unit 10 also causes the counter plate 7E to rotate in the opposite direction after the reverse rotation of the counter plate 7E has stopped, so that the gap G2 created during the reverse rotation disappears, there is no impact between the counter plate 7E and the wedge 7D during the next forward rotation of the electric motor 9.

[0050] As described above, in the present embodiment, after the forward or reverse rotation of the electric motor 9, the counter plate 7E is rotated in the opposite direction to eliminate the gap. Therefore, during the next rotation of the electric motor 9, the transmission of the impact shock to the occupant is reduced, thus preventing any unpleasant sensation for the occupant.

[0051] The control unit 10 executes the rotation reversal control in such a way that the torque generated at the electric motor 9 is below the cancellation torque. This prevents the backrest 5 from deviating from the preset angle at the end of the mode cycle.

[0052] Before the rotation reversal control begins, the control unit 10 performs a control to stop the excitation, thereby halting the excitation of the electric motor 9. In this way, when the rotation reversal control is executed, the gap G1, G2 between the wedge 7C, 7D and the counter plate 7E is reliably eliminated.

[0053] If, after completion of the automatic control, the control to stop the excitation were not executed, but only the rotation reversal control were executed, there would be a risk, due to the rotational inertia of the rotating devices, that the gap G1, G2 between the wedge 7C, 7D and the counter plate 7E would not disappear.

[0054] The control unit 10 preferably executes the automatic control, the excitation stop control, and the rotation reversal control sequentially in a single operating sequence. This prevents any other interruption actuation from occurring until the mode playback is complete. Thus, the gap between the wedge 7C, 7D and the counter plate 7E can be reliably eliminated once the mode playback is finished. Other embodiments

[0055] In the foregoing embodiment, the design is such that the rotation reversal control is implemented on the folding mechanism 7, which moves the backrest 5. However, the present disclosure is not limited to this. An embodiment is also possible in which the rotation reversal control is implemented after a control for moving a different movable section than the backrest 5 (for example, on a piece of armchair).

[0056] In the embodiment discussed above, the rotation reversal control is implemented on a device that incorporates a movable section, such as the backrest 5 or the like, with a wobble mechanism comprising the internal gear 7B, the external gear 7A, the keys 7C, 7D, and the counter plate 7E. However, the present disclosure is not limited thereto.

[0057] In the embodiment discussed above, the configuration is such that, when the rotation reversal control is executed, the electric motor 9 is controlled in such a way that the torque generated at the electric motor 9 is below the cancellation torque. However, the present disclosure is not limited to this.

[0058] It is also possible to configure the system with a sensor that directly or indirectly detects the gap G1, G2 and controls the electric motor 9 based on the sensor's reading. When controlled based on the reading, the motor torque can be equal to or greater than the lifting torque.

[0059] In the embodiment discussed above, the configuration is such that, following the automatic control that adjusts the angle of the backrest to the predetermined angle, the rotation reversal control is executed. However, the present disclosure is not limited to this. An embodiment is also possible in which the rotation reversal control is executed after the occupant has actuated a switch for forward or reverse rotation of the electric motor 9.

[0060] In the embodiment discussed above, the configuration is such that the control for stopping the excitation is executed before the rotation reversal control begins. However, the present disclosure is not limited to this. For example, an embodiment is possible in which the control for stopping the excitation is omitted.

[0061] In the embodiment discussed above, the configuration is such that the automatic control, the excitation stop control, and the rotation reversal control are executed sequentially in a single operating sequence. However, the present disclosure is not limited to this. For example, the automatic control, the excitation stop control, and the rotation reversal control can each be an independent operating sequence.

[0062] In the embodiment described above, the vehicle seat of the present disclosure is applied to a car. However, the application of the invention disclosed in the present document is not limited thereto. It can, for example, be applied to a seat used in a vehicle such as a railway carriage, a ship, an aircraft, and the like, as well as to a stationary seat used in theaters, homes, and the like.

[0063] As long as the present disclosure corresponds to the essence of the embodiment described above, it is not limited to that embodiment. Thus, it may include embodiments in which at least two of the embodiments described above have been combined, or embodiments in which any of the structural elements shown in the figures or described by reference numerals have been omitted from the embodiment described above. Explanation of reference symbols

[0064] 1...Vehicle seat; 3...Seat cushion; 5...Backrest; 7...Folding mechanism; 7A...External gear; 7B...Internal gear; 7C, 7D...Key; 7E...Counter plate; 7F...Spring; 7D...Key; 8...Counter plate; 9...Electric motor; 10...Control section QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2020-125072 A

[0002]

Claims

[1] Seat (1) with a folding mechanism in which the angle of a backrest (5) is variable, comprising: a backrest folding device (7) for changing the angle of a backrest (5), the backrest folding device (7) comprising an internal gear (7B), an external gear (7A), a wedge (7C, 7D) and a counter plate (7E), an electric motor (9) which generates a driving force for driving the counter plate (7E), and a control unit (10) for controlling the operation of the electric motor (9), wherein the control unit (10) can perform a rotation reversal control, wherein, when the rotation direction of the electric motor (9) when changing the angle of the backrest is regarded as the operation direction and the direction opposite to the operation direction is regarded as the reverse direction, the rotation reversal control is a control executed after the electric motor (9) rotates in the operation direction, wherein the control unit (10) causes the electric motor (9) to rotate in the reverse direction when executing the rotation reversal control within a range in which the angle of the backrest does not change. [2] The seat (1) according to claim 1, wherein, when a generated torque of the electric motor (9) required for changing the angle of the backrest is defined as a cancellation torque, the control unit (10), when executing the rotation reversal control, preferably controls the torque generated at the electric motor (9) to be below the cancellation torque. [3] The seat (1) according to claim 1 or 2, wherein the control unit (10) is capable of performing automatic control for bringing the angle of the backrest to a predetermined angle, the control unit (10) further performing the rotation reversal control after the automatic control. [4] The seat (1) according to claim 3, wherein the control unit (10) executes an energization stop control of stopping the energization of the electric motor (9) before starting to execute the rotation reversal control. [5] Seat (1) according to claim 4, wherein the control unit (10) preferably carries out the automatic control, the excitation stop control and rotation reversal control sequentially in a single operation sequence.

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