JPH0226481B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an electric reclining seat drive device, and particularly relates to an improvement in a drive method.

(Prior Art) An electric reclining seat and its driving device are known, which are equipped with a drive motor that drives the seat back to tilt forward or rearward around the rear end of the seat cushion of the seat.

FIG. 1 shows a schematic configuration of a conventional electric reclining seat drive device. When the forward/reverse motor 3 attached to the seat back 2 in the figure rotates, the motor rotates through three reduction gears 4a, 4b, 4c. Driving force is transmitted to the moving gear 5.

The rotating gear 5 is pivotally supported by a seatback bracket 6, and the seatback bracket 6 is pivotally supported by a seat cushion bracket 7.

Further, the rotating gear 5 is arranged to rotate around a fixed gear 9 attached to the seat cushion 8.

Therefore, the seat back bracket 6 also rotates in conjunction with the rotating gear 5, and the seat bag 2 attached to the seat back bracket 6 also rotates in the backward or forward direction.

In such electric reclining seats, when a person sits on the reclining seat,
Since the weight of the occupant's upper body is applied to the seat back, there is a difference in the required torque of the drive motor when tilting backwards and when standing up.

In other words, when a large occupant leans on the seatback and raises the seatback from its fully reclined state, the drive motor is forced to move as large as possible to overcome the weight of the occupant's upper body. Torque is required, and conversely, when tilting backwards, the weight of the occupant's upper body is added to the seatback and acts as a force to tilt backwards, increasing the driving force when tilting backwards, so less torque is sufficient than when tilting forwards. becomes. However, in the conventional device, the torque of the drive motor is kept to a level that does not pose any danger even if the legs of a passenger in the rear seat are pushed by the seat back of the front seat. For this reason, when a large person sits in the front seat and moves the seat from a backward leaning position to an upright position, the torque is sometimes insufficient.

(Purpose of the Invention) This invention has been made in an attempt to eliminate the above-mentioned drawbacks of the prior art, and provides a system that is safe even when the seatback of the seat is tilted backwards and can ensure sufficient torque even when standing up. The purpose of the present invention is to provide a driving device for an electric reclining seat.

(Structure of the invention) In order to achieve this object, according to the invention,
In an electric reclining seat drive device that includes a drive motor that moves the seatback between a rearward tilting state and an upright state, centering around the rear end of the seat cushion of the seat, when the seatback is tilted backward, the seatback is in the upright state. To provide a torque changing means that provides a smaller torque than when moving to.

(Effects of the Invention) With the above configuration, according to the present invention, it is possible to provide an electric reclining seat drive device that has the following effects.

(1) By making the torque when the seatback moves backwards smaller than the torque when returning it to the upright position, it is possible to ensure the safety of the rear seat occupants while ensuring the necessary torque when returning to the upright position.

(2) By changing the frictional resistance of the rotating bearing of the motor, it is possible to change the torque when returning the seat bag to the upright position when the seat bag is moved backwards with a simple configuration.

(3) By electrically changing the rotational torque of the motor, the torque value can be arbitrarily and appropriately set when the seatback is moved backward and when it is returned to the upright position.

(4) When the seat back is moved backward, the spring acts against the backward movement, and when the seat back is returned to the upright position, a force is applied to return it in the upright direction.By increasing the resistance when the seat back is moved backward, a simple method can be used. The structure allows you to change the torque when the seat back is tilted backwards and when it returns to the upright position.

(Embodiments of the invention) Examples of the invention will be described below with reference to the accompanying drawings.

FIG. 2 shows an embodiment of the present invention, in which the rear end 11 of the seat cushion 11 of the seat is shown.
The seat bag 12 is returned to an upright position (A) or moved to a rearward tilted position (B) with A as the center. The seat bag 12 has a gear 14 having a rotation center 13.
This gear 14 meshes with a worm gear 17 attached to a rotating body 16A extending to one side of the rotation shaft of the drive motor 15. Worm gear 17
Further forward, the rotating body 16A is supported by a support 18A with a surface where rotational friction increases.

A rotating body 16 is located on the other side of the rotating shaft of the drive motor 15.
B is extended and supported by a support body 18B via a means 19 such as a ball bearing that reduces rotational friction.

Note that the rotating bodies 16A and 16B may be the rotating shafts of the motor 15 themselves, or may be separate bodies.

With the above configuration, when the seat back 12 of the seat is moved in the upright direction A, the motor 15 rotates forward, for example, and the rotating bodies 16A and 16B receive a force to the left in the drawing. That is, the support body 18 is
The force is applied to the B side. Therefore, the torque of the drive motor 15 efficiently drives the seat back 12.

Conversely, when tilting the seat back 12 in the backward tilting direction B, the motor 15 rotates in the opposite direction and the rotating body 16
A and 16B receive force in the right direction in the drawing. In other words, the surface contact with the support body 1 has more frictional resistance.
Force is received on the 8A side. Therefore, the torque of the drive motor 15 suffers from a loss and becomes smaller than in the case of normal rotation.

As can be seen from the above, the frictional resistance between the rotating body 16A and the supporting body 18A is
By making the torque larger than that between 8B and 8B, the torque can be changed between the movement of the seat bag 12 in the upright direction and the movement in the backward tilting direction. Further, by adjusting the frictional resistance between the rotating body 16A and the support body 18A, the magnitude of the torque when tilting backward can be adjusted.

In addition to the above, as a mechanism for mechanically changing the torque, we have installed a spring that acts to resist the backward movement of the seatback when it is tilted backwards, and applies a force that returns the seatback in the upright direction when the seatback is returned to the upright position. The seat bag may be interposed between the cushion and the seat bag to increase the resistance when the seat bag moves backward, thereby causing a loss of torque when the seat bag moves backward.

FIG. 3 shows another embodiment of the invention, in which the torque is changed electrically.

By switching the power supply polarity of the DC motor, which is the drive motor 20, with the switch 21, the motor 20 is rotated in the forward and reverse directions to move the seat back in the upright direction or to move it backward.

In the illustrated state, the left side of the motor 20 becomes the positive electrode via the contact 21a of the switch 21. Further, the right side of the motor 20 is connected to a negative electrode via a contact 21b of a switch 21, a resistor 22, and a limit switch 23. When it is desired to switch the switch 21 in the opposite direction as shown, the right side of the motor 20 is connected to the positive pole, and the left side of the motor 20 is connected to the negative pole via the limit switch 23. At this time, the resistor 22 is not used.

The limit switch 23 consists of stators 23a, 23b, 2 arranged at a constant interval (several centimeters).
3c and a movable contact piece 23d that moves with the inclination movement of the seat back of the seat, and cuts off the power supply to the motor 20 when the seat back reaches a predetermined extreme position.

As can be seen from the above, by switching the switch 21, the resistor 22 is connected to the armature circuit of the motor 20, so that the torque is changed. Therefore, when the seatback is moved upright, no resistance is connected to maintain a large torque, and when the seatback is tilted back, a resistance is connected to reduce the torque.

There are various other ways to change the torque using electrical means, such as changing the torque by switching three brushes and selecting the number of turns of the armature winding, or preparing two armature windings with different numbers of turns, and A possible method is to select one by switching between them and change the torque.
Moreover, the same thing can be done by using a pulse motor as the drive motor.

The circuit for changing the torque by switching the three brushes will be explained as follows with reference to FIG.

First, when tilting backward (down), when the operation switch 24 is turned to the down side, the motor drive circuit K1
The interlocking switch 25 is connected to the down-side terminal 25a, and current can be supplied from the power source 26 through the interlocking switch 25.

Here, since the operation switch 24 is on the down side, the down side relay 27 is closed, and the current passing through the down side terminal 25a of the interlocking switch 25 is supplied to the G brush of the motor 28 through the relay 27. Further, since the up-side relay 29 is a normally closed relay, the current flows to the ground 30, and the motor 28 rotates to the down side through the limit switch 31.

On the other hand, the down side relay 32 is opened and no current flows through the up side drive circuit K3.

The limit switch 31 is provided with a rotating contact plate 33 on the arm side of the reclining device, and a fixed terminal 34 on the cushion side.

Next, when tilting forward (up), when the operating switch 24 is turned to the up side, the interlock switch 25 of the motor drive circuit K1 is connected to the up side terminal 25b, and current is passed from the power source 26 through the interlock switch 25. Supply becomes possible.

Here, since the operating switch 24 is set to the up side, the up side relay 29 is opened, the current from the interlocking switch 25 is supplied to the E brush of the motor 28, and the down side relay 3, which is a normally closed relay, is supplied to the E brush of the motor 28.
2, the limit switch 31, and the ground 30, causing the motor 28 to rotate in the upward direction.

Therefore, the present invention is not limited to the above-described embodiments, but includes various modifications within the scope that can achieve the object of the present invention.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the structure of an electric reclining seat, Fig. 2 is a block diagram showing the first embodiment of this invention, Fig. 3 is a system diagram of the second embodiment of this invention, and Fig. 4 FIG. 3 is an explanatory diagram of a third embodiment of the present invention. 11... Seat cushion, 12... Seat bag, 15... Drive motor, 16A, 16B...
Rotating body, 18A, 18B... Support body, 20... Drive motor, 21, 22... Torque changing means.

Claims (1)

[Scope of Claims] 1. In an electric reclining seat drive device that includes a drive motor that moves the seat back to a rearward tilting state and an upright state centered around the rear end of the seat cushion of the seat, the seatback is tilted backward. A driving device for an electric reclining seat, characterized in that it is equipped with a torque changing means that uses a smaller torque when moving the seat bag than when moving the seat back to an upright position. 2. In the device according to claim 1,
The torque changing means is characterized by comprising a rotating body extending on both sides of the rotating shaft of the drive motor, and a support that supports the rotating body from both sides and has a different frictional resistance with the rotating body on both sides. A drive device for electric reclining seats. 3. In the device according to claim 1,
An electric reclining seat drive device, wherein the torque changing means is an electric means for changing an armature current of the drive motor. 4. In the device according to claim 3,
An electric reclining seat driving device, wherein the electric means is an electric circuit that connects different resistances to an armature circuit when the drive motor rotates forward and reverse. 5. In the device according to claim 3,
An electric reclining seat driving device, wherein the drive motor is a DC motor having three brushes, and the torque changing means is an electric circuit that switches any two of the brushes and connects them to a power source. 6. In the device according to claim 3,
The drive motor has two armatures with different numbers of turns, and the torque changing means selectively connects one of the different armatures when the drive motor rotates in the normal direction and when the drive motor rotates in the reverse direction. An electric reclining seat drive device featuring: 7. In the device according to claim 1,
An electric reclining seat drive device, wherein the torque changing means is provided with a spring that is interposed between the seat cushion and the seat back and operates to generate a force that returns the seat back in an upright direction.