JPS638033A - Power seat device for automobile - Google Patents

Abstract

PURPOSE:To prevent an electric power source on vehicle from being wasted by providing a circuit controlling current to a motor whereby controlling the current consumption by the motor to be equal to or less than a certain value. CONSTITUTION:When a switching circuit 502 is turned on a relay coil (611) side, current flows from an elective power source terminal B to a power source terminal E through a diode 615. As a result, the transistor 634 of a breaker circuit 630 is energized for actuating a relay contact 611' correspondingly. Said actuation caused current to flow from the power source terminal B to the power source terminal E through the transistor 621 of a current limiting circuit 620 for starting a motor 303. In this case, the starting current of the motor 303 is kept to a value equal to or less than a certain value by the current limiting circuit 620. Owing to this constitution, as the motor 303 can be used in a range of high efficiency there is no need for use of a great capacity of motor and an electric power source on vehicle is not wasted. In addition, in case of over loading, the motor is de-energized for preventing a driving device from being destroyed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power seat device for an automobile that drives an automobile seat reclining device, a seat rail device, etc. by a motor.

[Conventional technology]

2. Description of the Related Art Conventionally, power seat devices have been known that drive reclining devices and seat rail devices for automobile seats using motors controlled by switches or relays. Conventional devices of this type have employed a large DC magnet motor that has a large starting torque and has the characteristics of high torque and low speed rotation that can sufficiently withstand overload during locking.

[Problem that the invention seeks to solve]

The motor in the conventional device described above has a high torque (maximum of about 3 kg-cm) and low speed rotation (maximum of about 3 kg-cm) as shown in Fig. 4.
, 500 times/min), a large magnet with a large magnetic flux is used as the fixed magnetic pole, and the rotor has 8 poles with an overlapping winding configuration. It had a large structure with thick rotor windings and mechanical strength that could withstand the heat generated by the large currents generated during periods. For this reason, conventional power seat devices are large and difficult to integrate into small car seats, and
There was a problem in that the device was expensive because it used a motor with extra power. In addition, in the above-mentioned conventional device, the motor having the characteristics of high torque and low speed rotation is controlled to drive in the shaded area in FIG. 4 via a switch or relay. When the load torque fluctuates greatly, such as when adjusting the back from a horizontal position to an upright position, the driving speed changes significantly depending on the seat back's tilted position, making it impossible to obtain smooth driving and a good operating feel. was there. Furthermore, the area indicated by diagonal lines in Figure 4 is a region where the motor is inefficient. ! ! There was a problem in that power was wasted and the motor generated heat due to large current during overload.

In addition, if a large reducer is used in conventional equipment, it is possible to reduce changes in drive speed due to fluctuations in load torque, but the drive speed may become too slow (or the output torque may be too large, causing problems on the driven side). In some cases, the drive device itself may be destroyed.

[Means to solve the problem]

Equipped with a small motor that rotates at high speed with low torque, a current control circuit that controls the motor current, and a large reducer that reduces the high speed rotation output of the motor, the current control circuit maintains the motor current below a certain value. The present invention is characterized in that the power supply to the motor is cut off in the event of an overload such as locking, and that the high-speed rotational output of the motor is transmitted to the driven device via a large speed reducer.

[For production]

The current control circuit drives the motor below a certain current value, and the low-torque, high-speed output of the motor is transmitted to the driven device as high-torque, low-speed driving force via a large reducer, resulting in power seat equipment. is activated.

In addition, since the current consumption of the motor is regulated below a certain value by the current control circuit, the output torque of the motor and the output torque transmitted to the driven device via the large reducer are also regulated below a certain value. At the time of overload, the power to the motor is restarted, the motor is stopped, and the operation of the power seat device is canceled.

〔Example〕

First, the overall configuration of the power seat device of the present invention will be explained with reference to FIG. The automobile seat includes a seat cushion 1 and a seat back 2. The seat cushion 1 is attached to the body of the automobile via a seat rail device, and the seat back 2 is attached to the rear end of the seat cushion 1 via a reclining device. is hinged to. The seat rail device mainly includes an upper rail 301 to which the seat cushion 1 is fixed, a lower rail 302 that is slidably fitted onto the upper rail 301 and fixed to the vehicle body, a small motor 303 with low torque and high speed rotation, and a motor 30.
The rotational output of 3 is significantly reduced to create a threaded rod-shaped drive member 30.
It consists of a large decelerator 305 that transmits data to 4. Further, the reclining device ↓ has a bracket 401 fixed to the seat cushion 1 and a bracket 402 fixed to the seat back 2, and both brackets are rotatably connected to each other by a shaft 413. Furthermore, between the two brackets, there is a worm 404 and a worm wheel 405 that reduce the rotational output of a small motor 403 that rotates at high speed with low torque.
A large speed reducer is interposed, which is a combination of a speed reduction mechanism consisting of the above and a differential gear speed reduction mechanism (not shown) that further slows down the rotation of the worm wheel 405. (The differential gear reduction mechanism is a known mechanism composed of internal and external gears carved on both brackets and an eccentric shaft portion of the shaft 413.
It is not shown in FIG. ) 5 is a switch disposed on the side surface of the seat cushion 1. By operating the switch 5, the small motors 303 and 403 are rotated in the normal direction through the current control circuit 6 disposed within the seat cushion l. It controls reversing, starting, and stopping.

The above-mentioned small motors 303 and 403 use small magnets as fixed magnetic poles, and have a three-pole rotor with a single winding, simple structure, small size, and low torque as shown in Figure 2. It has the characteristic of high-speed rotation, and has a structure that has only extremely short-term durability against heat generation due to large current (approximately 2OA) when locked (restrained).

Next, the configurations of the switch 5 and the current control circuit 6 will be explained with reference to FIG. Switch 5 is diode 501
and two switch circuits 502 and 503.

The current control circuit 6 includes a relay circuit 610 that responds to the operation of the switch 5, and a current control circuit 6 that keeps the current of the motor 303, 403 below a certain value (5A or below in this embodiment).
20, and a breaker circuit 630 that deactivates the relay circuit 610 and releases the drive of the motor 303.403 when a set current value (4 A or more in this embodiment) flows through the motor 303.403 for a certain period of time. It has become. The relay circuit 610 includes four relay coils 611~
614 and relay contacts 611/~6' that respond to this magnetic force.
14' and diodes 615 to 618, and the motors 303 and 403 are configured to rotate forward, reverse, or stop depending on the operation of the switch 5. Current control circuit 6
20 is a transistor 621 and diodes 622 to 62
4 and resistor 625.626, motor 303.4
03 in series to keep the current of the motors 303 and 403 always below a certain value. Breaker
The circuit 630 includes a transistor 631, a capacitor 632,
It consists of a delay circuit made up of a resistor 633, a switching circuit made up of a transistor 634 and resistors 635 and 636, which cut off the current of the relay circuit 610 by the output of the delay circuit. Also, capacitor 6 of the delay circuit
32 is a transistor 621 of the current control circuit 620.
It is designed to be charged from the collector of the circuit through resistors 637 and 638.

Next, the operation of the power seat device configured as described above will be explained. For example, when the switch 5 is operated and the switch circuit 502 is connected to the relay coil 611 side, the diode 501, the switch circuit 502,
Current flows to power supply terminal E via diode 615 and resistors 635 and 636. Then, the transistor 634 of the breaker circuit 630 becomes conductive, the relay coil 611 of the relay circuit 610 is energized, and the relay contact 611/ responds. Further, in response to the response of the relay contact 611', current flows from the power terminal B to the power terminal E via the relay contact 611', the motor 303, the relay contact 612', the transistor 621 of the current control circuit 620, and the motor 303 is started. At this time, the starting current of the motor 303 is controlled by the current control circuit 62.
0 is limited to below a certain value (5A or less), and after starting with the torque Po (approximately 0.42 kg-cm) shown in Figure 2 and reaching a steady state, P is on the line of torque - rotation speed P + - Pz. is driven by. Note that in a preferred embodiment of the present invention, the load torque of the motor 303 in a steady state is 0.1 to
A large reducer with a speed of 0.3 ktr (approximately 25 times the reduction ratio compared to the reducer of conventional equipment) is adopted, and the motor 303 is extremely efficient and has a second drive speed with little change in drive speed due to fluctuations in load torque. Used in the shaded area in the figure.

Here, if the motor 303 rotates in the normal direction, the upper rail 301 of the seat rail device is adjusted to move forward with respect to the lower rail 302 together with the seat cushion 1, and if the switch circuit 502 is turned on the opposite side, the motor 303 rotates. The seat 1 is moved backward and adjusted in the reverse direction. Further, when the switch circuit 503 is turned on to either side, the motor 403 is driven in the same manner as the aforementioned motor 303, and the inclination angle of the seat back 2 is adjusted in circumference by the operation of the reclining device ball.

In addition, during the above operation, a problem may occur on the driven side of the seat rail device or the reclining device, causing the motor 3
03 or when an excessive load torque acts on the motor 403, the motor current value flowing through the current control circuit 620 of the current control circuit 6 increases to more than the set value (4A), and this is detected by the breaker circuit 630 and the motor The power to the device is cut off and the device stops operating. In other words, in the event of an overload such as a lock, the breaker circuit automatically cuts off the power to the motor, and the motor 30
3.403 damage and destruction of the drive device due to excessive torque is prevented.

〔Effect of the invention〕

The power seat device for an automobile of the present invention includes a small motor that rotates at high speed with low torque, a current control circuit that controls the current of the motor, and a large reducer that decelerates the high speed rotation output of the motor. The device is configured to keep the motor current below a certain value, making it easier and cheaper to incorporate into a small vehicle than a conventional device using a large motor. In addition, the current control circuit allows the motor to be used in a region below a certain current value, that is, in a highly efficient region, so it is possible to use a large, expensive motor that has sufficient durability against heat generation and other problems, as in conventional devices. It is not necessary, and furthermore, it does not waste on-vehicle power supply. In addition, since the current control circuit regulates the motor's current consumption and output torque to below a certain value, excessive torque may act on the driven side via the large reducer, causing inconveniences such as destroying the drive device itself. It does not occur.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the present invention, FIG. 2 is a diagram showing the characteristics of an actual motor, and FIG. 3 is a circuit diagram showing a current control circuit. FIG. 4 is a diagram showing the characteristics of the motor of the conventional device. [Explanation of symbols] 1... Seat cushion, 2... Seat back, 3
...Seat rail device, soil...Reclining device, 303.403...Motor, 5...Switch, 6
...Current control circuit

Claims (1)

[Claims] 1. A power seat device that drives and adjusts a reclining device, a seat rail device, etc. using a motor, which includes a small motor with low torque and high speed rotation, a current control circuit that controls the current of the motor, and a current control circuit that controls the current of the motor. A power seat device for an automobile, comprising a decelerator that decelerates a high-speed rotation output, and is configured such that the current consumption of the motor is regulated to a certain value or less by the current control circuit.