JPH04137496U - Switch circuit in drive unit - Google Patents

Abstract

(57) [Summary] [Purpose] By performing switching using a PTC element, the number of electrical circuit components can be reduced, and burnout of the motor can be reliably prevented. In addition, by physically and forcibly stopping the moving object with a stopper, etc., it is possible to mechanically downsize the motor and drive force transmission mechanism and reduce the capacity, and the moving object can be kept at a specified level without rattling. Can be stopped at a stop position [Configuration] Temperature range where the temperature rises due to overcurrent that occurs when a moving object is physically and forcibly stopped by a stopper etc. and the motor is overloaded. When the resistance value suddenly increases, a PTC element that performs a switching operation is connected in series between the switch and the motor in an antiparallel state, and the PTC element performs the switching operation in conjunction with the switching operation of the PTC element. Connect a timer circuit that cuts off power to the PTC element.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a switch circuit in a drive device, and in particular electrical circuit components. It is possible to reliably prevent burnout of the motor, and mechanically it is possible to The motor and drive force transmission mechanism can be made smaller and smaller in capacity, and the moving object does not shake. Concerning a switch circuit in a drive device that can be stopped at a predetermined stop position It is something that

0002

[Conventional technology]

A drive device generally consists of a power source, a motor connected to the power source via a switch, and , is linked to the motor via a drive force transmission mechanism and moves by the drive of the motor. A moving body is provided. By operating the switch to energize the motor, The motor is driven, and the driving force of the motor is transmitted to the moving object via the driving force transmission mechanism. reached, and the moving object moves. Then, at a predetermined stop position, the switch The drive of the motor is stopped by operating the button to cut off the power to the motor. , the moving body stops at a predetermined stop position. The drive device described above is used in various devices. For example, electric power in automobiles Dynamic retractable door mirrors, power windows, power antenna, retractable run Slide devices, rotation devices, opening/closing devices for cars, power seats, and other fields. Widely used for installation, etc. Many of these drive devices stop a moving body at a predetermined stop position and also include a motor. Equipped with a switch circuit that cuts off the power to the

0003

[Problem that the idea aims to solve]

However, the switch circuit in the conventional drive device described above is electrically connected to the circuit section. There are many components, and there is a risk of burning out the motor, and mechanically, there is a risk of damage to the motor and drive power transmission. The reaching mechanism has become larger and has a larger capacity, and can stop the moving object at a predetermined stop position without any play. There are problems such as the difficulty of

0004 The purpose of this invention is to reduce the number of electrical circuit parts and to ensure that the motor does not burn out. Mechanically, the motor and drive force transmission mechanism can be made smaller and have a smaller capacity. It is possible to stop the moving object at a predetermined stop position without any rattling. An object of the present invention is to provide a switch circuit in a drive device that can be used.

[0005]

[Means to solve the problem]

In order to solve the above-mentioned problems, this invention aims to prevent the moving object from physically stopping with a stopper etc. The overcurrent that occurs when the motor is stopped and overloaded causes the temperature to rise. When the temperature reaches a certain temperature range, the resistance value increases rapidly and the PTC element performs switching operation. One set consists of a diode and a diode connected in series, and these two sets are connected in reverse parallel. the PTC element is connected in series between the switch and the motor in a column state; A timer circuit that is linked to the switching operation of the PTC element is connected to the Features.

[0006]

[Effect]

This invention uses a PTC element whose resistance value increases rapidly as the temperature rises. By performing this, compared to switching using a current detection element, etc. , fewer circuit components are required. Moreover, switching is instantaneous, so , motor burnout can be reliably prevented. In addition, with the above configuration, the moving object can be physically and forcibly stopped using a stopper, etc. Since the drive of the motor is stopped after the There is no crushing, and as a result, the moving object can be stopped at a predetermined stopping position without rattling. can. Moreover, with the above configuration, the moving object can be moved to a position other than the predetermined stop position. If the moving object is physically and forcibly stopped for some reason, the moving object Because it stops at a certain position, the moving object is physically stopped at a position other than the predetermined stopping position. Also, the clutch mechanism to prevent the motor from burning out if the motor is forcibly stopped is missing. The key point. As a result, the driving force of the motor is slightly greater than the movement resistance of the moving object. Therefore, it is necessary to downsize the motor and drive force transmission mechanism and reduce the capacity. can be done.

[0007] In particular, the present invention uses a set of PTC elements and diodes connected in series. , these two sets are connected in series between the switch and the motor in an anti-parallel state. Therefore, after moving a moving object in a certain direction, the moving object can be moved in the opposite direction. When one PTC element is in a high resistance state as the temperature rises, However, since the other PTC element has a low resistance value at room temperature, the motor cannot be driven. In addition, the above-mentioned moving body can be instantly moved in the opposite direction. In this way, other The internal temperature of one PTC element decreases due to one PTC element, and the temperature rises again. It is possible to buy time until the switching operation becomes possible.

[0008] Moreover, the two PTC elements are connected to the switching operation of the PTC elements. The PTC element is connected to a timer circuit that cuts off power to the PTC element. When the C element switches, the timer circuit is linked and the communication to the PTC element is activated. Since the power can be cut off, the durability load of the PTC element can be reduced. Ru.

[0009]

【Example】

An embodiment of the switch circuit in the drive device of the present invention will be described below with reference to the attached drawings. I will explain. This example is an example of application to an electric retractable door mirror of a car. In the figure, 1 is a mirror base fixed to the vehicle body. 2 is a hollow shaft 3 is integrally implanted, and this shaft holder 2 is attached to the mirror. Fix it to base 1. The shaft 3 is provided with a chamfered portion 4 for preventing rotation. An engagement groove 5 is provided in the upper end of the shaft 3 in the circumferential direction. Above the shaft holder 2 When the mirror assembly 7, which will be described later, is rotated on the fixed surface of the surface, A pair of arc-shaped grooves 6 are provided along the arc locus of the ball 12 incorporated in the assembly 7. Ru. As shown in FIG. 6, this arcuate groove 6 has a height cut at right angles to both ends It has H step portions 60 and 61. The positions of the stepped portions 60 and 61 at both ends are determined by the distance described below. Use position of the mirror assembly 7 (as shown by the solid line in Figure 2) (indicated by the dashed line in Figure 2) and the storage position (indicated by the dashed line in , the mirror assembly 7 is tilted backward along the vehicle body). . Note that the bottom surface of the above-mentioned arcuate groove 6 may be smooth as long as it is smooth, for example, as shown by the two-dot chain line. It may also have a gently upwardly convex shape as shown in FIG.

0010 Reference numeral 7 denotes a mirror assembly as a movable body, and this mirror assembly 7 A unit bracket 8 rotatably supported on the foot 3 and this unit bracket. The mirror housing 9 and the power unit 10 fixed to the The mirror housing 9 is mounted on the mirror housing 9 so as to be tiltable vertically and horizontally. A mirror 11 is provided at the mouth. The circle of the shaft holder 2 within the rotating surface of the lower surface of the unit bracket 8 A hemispherical recess is provided at a location facing the arcuate groove 6, and the ball 12 can be rolled in the recess. Incorporate it into Noh. As shown by the solid line in FIG. 6, this ball 12 hits the stepped portion 60 on the use position side. When the mirror assembly 7 is in use, the mirror assembly 7 is in the use position. Also, this board As shown by the dashed line in FIG. When the mirror assembly 7 is opened, the mirror assembly 7 is in the retracted position. Furthermore, this As shown by the two-dot chain line in FIG. When the mirror arm rests on the fixed surface of shaft holder 2, When the assembly 7 is rotated manually or by buffer rotation, as shown by the two-dot chain line in FIG. It is in a state where it is tilted forward along the . The stepped portions 60 and 61 at both ends of the above-mentioned arcuate groove 6 and the ball 12 serve as a moving body. The mirror assembly 7 is physically and forcibly stopped at a predetermined stop position. This is what constitutes the upper part. Also, the height of the stepped portions 60 and 61 of this arcuate groove 6 The torque of the motor 13, which will be described later, does not allow the ball 12 to ride on the H and the ball 12. The stopper should be large enough to ride on during movement or buffer rotation.

[0011] 22 and 23 are protrusions and 23 protruding from the fixing surface on the upper surface of the shaft holder 2. and a semi-circular groove provided on the rotating surface of the lower surface of the unit bracket 8. 22 is slidably fitted into the groove 23. 13 is a motor built into the mirror assembly 7; It is installed on a plate 14 fixed to the unit bracket 8. this motor 13 is electrically connected to the battery 31 via a switch circuit of the present invention which will be described later. has been done. 15 is a clutch mechanism attached to the shaft 3, and this clutch mechanism 15 is Rotate the mirror assembly 7 manually or insert something into the mirror assembly 7. The movement occurs when the mirror assembly 7 is rotated to cushion the impact. The mirror assembly 7 on the side, the motor 13, and the deceleration mechanism 24 to be described later, and the fixed side This is to cut off the edge between mirror base 1, shaft holder 2, and shaft 3. . The clutch mechanism 15 includes a push nut fitted onto the shaft 3 in order from above. 16, compression spring 17, clutch gear 19, and clutch holder 20 and washers 18 and 21. The clutch gear 19 is rotatable with respect to the shaft 3 and is engaged with the lower surface. Provide a stop groove. The clutch holder 20 is fixed to the shaft 3. , a locking claw is provided on the top surface. The push nut 16 fits into the engagement groove 5 of the shaft 3. to compress the compression spring 17. This compression spring 17 Due to force, the clutch holder 20 is inserted into the locking groove on the lower surface of the clutch gear 19. The locking pawl on the top surface locks the clutch gear 19 and the clutch holder 20. is in a state of succession. Also, due to the elastic force of the compression spring 17, the and the shaft holder 2 is moved upward (on the contrary, the unit brake is moved through the clutch mechanism 15). 8), and as a result, the ball on the unit bracket 8 side 12 is pressed against the bottom surface of the arcuate groove 6 of the shaft holder 2.

0012 24 is a driving force transmission mechanism disposed between the clutch mechanism 15 and the motor 13; This speed reduction mechanism 24 is a first speed reduction mechanism attached to the output shaft of the motor 13. A worm 25 and a first worm wheel 2 meshed with the first worm 25 6, and one of the rotating shafts is inserted into the center hole of the first worm wheel 26 by the D-cut surface. a second worm 27 whose end is movable in the axial direction and non-rotatable; The second worm wheel 28 meshed with the second worm 27, and the second worm wheel 28 meshed with the second worm 27; A gear 29 on the motor side fixed coaxially to the wheel 28, and a gear 29 on the motor side. An idle gear 30 is interposed between the clutch gear 19 and the clutch gear 19. That is, this The idle gear 30 is engaged with the gear 29 on the motor side and the clutch gear 19. make it happen The speed reduction mechanism 24 includes the unit bracket 8 and the unit bracket. The plate 14 fixed to 8 and attached to the plate 14 with screws 33 The support 32 is equipped with the support 32. In addition, the shaft 3, motor 13, Keratchi mechanism 15, deceleration mechanism 24, etc. The gear case portion 44 provided on the unit bracket 8 and its gear case It is covered by a lid 45 fitted and attached to the upper opening of the space part 44.

[0013] The operation of the electrically retractable door mirror configured as described above will be explained below. I will clarify. First, the motor 13 is driven. Then, the rotational force (driving force) of the motor 13 is transmitted to the idle gear 30 via the two-stage worm gear and the gear 29 on the motor side. Waru. Here, since the clutch gear 19 and the clutch holder 20 are in a connected state, , this clutch gear 19 is in a fixed state. As a result, the idle gear 30 is It revolves around the gear 19 while rotating. As this idle gear 30 revolves, The mirror assembly 7 rotates by an angle θ relative to the shaft 3 of the mirror base 1. , when this mirror assembly 7 is moved from the use position to the storage position or from the storage position to the use position. rotationally displaced to the position for use. At this time, mirror assembly 7 and unit bracket The ball 12 on the 8th side runs along the arcuate groove 6 on the mirror base 1 and shaft holder 2 side. It rolls in the direction of the arrow □ or □. Then, the above-mentioned ball 12 is inserted into the step of the arcuate groove 6. When it hits part 60 or 61, the switch circuit of the present invention, which will be described later, is activated and the motor is turned off. The drive of the motor 13 is stopped, and the mirror assembly 7 is at a predetermined stop position, i.e. Stops in use or storage position. Also, when the mirror assembly 7 is in the use position, this mirror assembly is If an obstacle or the like hits 7 with a force greater than the elastic force of the compression spring 17, or the garage When taking the mirror assembly 7 in and out of the If it is rotated with a force larger than the force, the clutch gear 19 of the clutch mechanism 15 and the The clutch holder 20 is disconnected, and the clutch gear 19 rotates with respect to the shaft 3. Accordingly, the mirror assembly 7 is moved from the use position to the storage position or from the storage position. It rotates from the position to the use position, and further tilts forward at an angle φ from the use position.

[0014] Figure 1 is an electric circuit showing an embodiment of the switch circuit in the drive device of the present invention. It is a diagram.

[0015] In the figure, 31 is a battery as a power source, and this battery 31 is used for automobiles. This is a normal 12V DC battery installed in the. 37 is a switch located on the driver's seat, and this switch 37 is a switch for changing polarity. In this example, a 3-position changeover switch with two movable contacts is used. child The switch 37 has a first movable contact 371 and a second movable contact 372 that are interlocked. , a first common contact COM1 and a second common contact COMCOM2, and the battery. The first + contact A1 and the second + contact A2 connected to the + pole of -31, respectively, and the A first contact B1 and a second contact B2 connected to the negative pole of the battery 31, respectively. , a first intermediate contact C1, and a second intermediate contact C2. This switch 37 , in the normal state, the movable contacts 371 and 372 are connected to the middle contacts C1 and C. It is in contact with 2. Reference numeral 13 denotes the motor, and this motor 13 is connected in series to the switch 37. That is, one terminal of the motor 13 is connected to the first common contact COM1 of the switch 37. Then, connect the other terminal of the motor 13 to the second common contact COM2 of the switch 37. Connect each.

[0016] 38 and 39 are a first PTC element and a second PTC element that utilize resistance temperature characteristics. These PTC elements 38 and 39 are short circuits whose resistance value changes rapidly in a certain temperature range. For example, polymer-based PTC elements (products of Raychem Co., Ltd.) exhibiting switching characteristics. (named polyswitch). These PTC elements 38 and 39 are used as moving objects. The mirror assembly 7 has a stopper (steps 60, 61 and ball 12), etc. When the motor 13 is physically and forcibly stopped by The internal temperature rises due to the overcurrent that occurs in the This increases the switching operation.

[0017] 41 and 42 are first dies for selecting the current flow and selecting the PTC element; anode and a second diode. This first diode 41 and the second diode A code 42 is connected in series to the first PTC element 38 and the second PTC element 39, respectively. The motor 13 and the switch 37 are connected in an anti-parallel state. Connect in series between. That is, the cathode of the first diode 41 is connected to the switch. The anode of the first diode 41 is connected to the first common contact COM1 of the switch 37. Place the other terminal of the first PTC element 38 in front of one terminal of the first PTC element 38. The two terminals are connected to one terminal of the motor 13, respectively. Further, the second PTC element 39 One terminal of the switch 37 is connected to the first common contact COM1 of the second PTC element. The other terminal of the child 39 is connected to the anode of the second diode 42. The cathodes of the leads 42 are connected to one terminal of the motor 13, respectively.

[0018] 40 is a timer interlocked with the switching operation of the PTC elements 38 and 39; In the circuit, this timer circuit 40 is connected in series with the PTC elements 38 and 39. Ru. That is, both terminals of the timer circuit 40 are connected to the other terminal of the motor 13. They are respectively connected to the second common contact COM2 of the switch 37. This timer circuit 40 operates in conjunction when the PTC elements 38 and 39 switch. After a predetermined set time has elapsed, the current in the circuit is cut off.

[0019] Next, the operation of the above-mentioned electric circuit will be explained. First, operate the switch 37 to move the movable contacts 371 and 372, respectively. + contact A1 and - contact B2. Then, the power from battery 31 The flow is in the direction of the solid arrow: second PTC element 39 → second diode 42 → motor 13 → The current flows to the timer circuit 40, the motor 13 rotates (forward rotation), and the rotation of the motor 13 The force causes the mirror assembly 7 to rotate, for example from the use position to the storage position, as described above. move. Then, the mirror assembly 7 reaches the retracted position, which is the predetermined stopping position. At this point, the stopper is activated, which means that the ball 12 on the movable side moves into the circular arc on the fixed side. When the mirror assembly 7 hits the stepped portion 61 of the shaped groove 6, the mirror assembly 7 is moved to the retracted position, which is a predetermined stopping position. be physically and forcibly stopped. At this time, the motor 13 is overloaded. is applied, causing an overcurrent to flow in the electrical circuit. This overcurrent causes the second PTC element 3 When the internal temperature of the second PTC element 39 increases and reaches a certain temperature range, the internal resistance of the second PTC element 39 increases. increases rapidly, and this second PTC element 39 performs a switching operation. Then, The timer circuit 40 is interlocked to cut off power to the circuit after a predetermined set time has elapsed. As a result, the rotation (drive) of the motor 13 is stopped and the mirror assembly 7 is moved to the storage position. Stop completely at . Therefore, the operation of the switch 37 is stopped and the movable contact 3 71 and 372 are automatically returned to intermediate contacts C1 and C2. Next, operate the switch 37 to move the movable contacts 371 and 372, respectively. - contact B1 and + contact A2. Then, the power from battery 31 The flow is in the direction of the one-dot chain arrow, from the timer circuit 40 to the motor 13 to the first PTC element 38. →Flow to the first diode, the motor 13 rotates (reversely), and the rotation of the motor 13 The force rotates the mirror assembly 7, for example from the storage position to the use position, as described above. move. Then, the mirror assembly 7 reaches the use position, which is the predetermined stop position. At this point, the stopper is activated, which means that the ball 12 on the movable side moves into the circular arc on the fixed side. The mirror assembly 7 hits the step 60 of the shaped groove 6, and the mirror assembly 7 is in the use position, which is a predetermined stopping position. be physically and forcibly stopped. At this time, the motor 13 is overloaded. is applied, causing an overcurrent to flow in the electrical circuit. This overcurrent causes the first PTC element 3 When the internal temperature of the first PTC element 38 increases and reaches a certain temperature range, the internal resistance of the first PTC element 38 increases. increases rapidly, and this first PTC element 38 performs a switching operation. Then, The timer circuit 40 is interlocked to cut off power to the circuit after a predetermined set time has elapsed. As a result, the rotation (drive) of the motor 13 is stopped, and the mirror assembly 7 is moved to the use position. Stop completely at . Therefore, the operation of the switch 37 is stopped and the movable contact 3 71 and 372 are automatically returned to intermediate contacts C1 and C2. In this way, the switch circuit of the present invention in this embodiment has a resistance that increases as the temperature rises. The switch is activated by the first PTC element 38 and the second PTC element 39 whose resistance value increases rapidly. Since the device performs switching operation, switching can be performed using a current detection element, etc. It requires fewer circuit components compared to . Moreover, the above-mentioned switching operation Since this is done instantaneously, burnout of the motor 13 can be reliably prevented.

[0020] In addition, the switch circuit of the present invention in the above-mentioned embodiment is a mirror as a moving object. After physically and forcibly stopping the assembly 7 with the stoppers 12, 60, and 61, Since the drive of the motor 13 is stopped, the deceleration mechanism is used as a driving force transmission mechanism. There is no backlash in 24 gear groups. As a result, the mirror assembly 7 It can be stopped at a predetermined stop position, i.e., the use position or the storage position, without any trouble. Wear. Moreover, the rotating mirror assembly 7 is not at a predetermined stop position. If the mirror assembly 7 is physically and forcibly stopped for some reason, the mirror assembly 7 The switch circuit of the present invention described above stops the mirror assembly at that position, so the rotating mirror assembly can be stopped at that position. If the yellowtail 7 is physically and forcibly stopped at a position other than the predetermined stopping position, In this case, there is no need for a clutch mechanism or the like to prevent the motor 13 from burning out. As a result, The driving force of the motor 13 is the rotation resistance of the mirror assembly 7, that is, the ball 12 is circular. It is sufficient that the resistance is slightly greater than the resistance of rolling in the arcuate groove 6. Therefore , the motor 13 and the speed reduction mechanism 24 can be made smaller and have a smaller capacity. Also, buffer The clutch torque of the clutch mechanism 15 for the engine is increased separately from the torque of the motor 13. This allows the mirror assembly 7 to be held without any wobbling. As a result, there is no risk that the image reflected on the mirror 11 will be blurred.

[0021] In particular, the switch circuit of the present invention in this embodiment includes two PTC elements 38 and and 39 are connected in parallel between the switch 37 and the motor 13. Therefore, after rotating the mirror assembly 7 in one direction, When rotating the bridge 7 in the opposite direction, one PTC element 38 or 39 Even if it is in a high resistance state as the temperature rises, the other PTC element 39 or 38 Since it is in a state of low resistance value at room temperature, the motor 13 is driven and the mirror assembly described above is The assembly 7 can be instantly rotated in the opposite direction. In this way, the other PTC The element 39 or 38 causes one of the PTC elements 38 or 39 to This allows you to buy time until the temperature of the parts falls and switching operation becomes possible again. Wear.

[0022] Moreover, the two PTC elements 38 and 39 are connected to each other. A timer circuit 4 that cuts off the power to the PTC element in conjunction with the switching operation. 0 are connected in series, PTC element 38 or 39 is the switching When activated, the timer circuit turns OFF and energizes the PTC element 38 or 39. Since the PTC elements 38 and 39 can be cut off, the durability load of the PTC elements 38 and 39 can be reduced. be able to.

[0023] In the above-described embodiment, the step portion 60 of the arcuate groove 6 serves as the stopper. Although a ball 61 and a ball 12 are used, other techniques may be used. In addition, in the above embodiment, an electrically retractable door mirror for an automobile is described. However, it can also be used as a switch circuit for other drive devices. Furthermore, in place of the switch 37 in the above embodiment, an operation holding type switch is used. May be used.

[0024]

[Effect of the idea]

As is clear from the above, the switch circuit in the drive device of the present invention Switching is performed using a PTC element whose resistance value increases rapidly as the temperature rises. Therefore, compared to circuits that perform switching using current detection elements, less. Moreover, since switching is instantaneous, there is no risk of motor burnout. can be reliably prevented. In addition, the moving object must be physically and forcibly stopped with a stopper, etc., and then the motor cannot be driven. Because it stops the drive force transmission mechanism, there is no backlash. As a result, the moving body can be stopped at a predetermined stopping position without any play. Moreover, the transfer A moving object may be physically and/or If the moving object is forcibly stopped, the moving object is configured to stop at that position. When a moving object is physically and forcibly stopped at a position other than the predetermined stopping position. There is no need for a clutch mechanism to prevent the motor from burning out if the motor is damaged. As a result , it is sufficient that the driving force of the motor is slightly greater than the movement resistance of the moving object. Therefore, the motor and the driving force transmission mechanism can be made smaller and have a smaller capacity.

[0025] In particular, the switch circuit of the present invention can switch two PTC elements in anti-parallel state. Since it is connected in series between the chain and the motor, it is possible to move the moving object in a certain direction. When the moving object is moved in the opposite direction after Even if it has a high resistance value as the temperature rises, the other PTC element has a low resistance value at room temperature. drive the motor to instantly move the above-mentioned moving object in the opposite direction. can be done. In this way, one PTC element is controlled by the other PTC element. the time it takes for the internal temperature to drop and switching operation to be possible again. You can earn money.

[0026] Moreover, the switch circuit of the present invention has two PTC elements and a switch of the PTC element. Connect a timer circuit that cuts off the power to the PTC element in conjunction with the switching operation. Therefore, when the PTC element switches, the timer circuit is activated. The power to the PTC element can be cut off by moving the PTC element, reducing the durability of the PTC element. The load can be reduced.

[Brief explanation of drawings]

FIG. 1 is an electric circuit diagram showing an embodiment of a switch circuit in a drive device according to the present invention.

FIG. 2 is a partially cutaway plan view of an electric retractable door mirror for an automobile equipped with the switch circuit of the present invention.

FIG. 3 is a sectional view of a motor, a driving force transmission mechanism, and a moving body in an assembled state.

FIG. 4 is an exploded perspective view of a motor, a driving force transmission mechanism, and a moving body.

FIG. 5 is a view taken along the V arrow in FIG. 4;

FIG. 6 is a VI-VI line development diagram in FIG. 5;

[Explanation of symbols]

1 Mirror base 2 Shaft holder 3 Shaft 6 Arc groove 7 Mirror assembly (moving object) 8 Unit bracket 12 Ball (stopper) 13 Motor 15 Clutch mechanism 24 Reduction mechanism (driving force transmission mechanism) 31 Battery (power supply) 37 Switch 38 PTC element 39 PTC element 40 Timer circuit 41 Diode 42 Diode 60 Stepped part (stopper) 61 Step part (stopper)

Claims (1)

[Scope of utility model registration request] 1. A drive device comprising: a power source; a motor connected to the power source via a switch; and a moving body linked to the motor via a drive force transmission mechanism and moved by the drive of the motor. This is an overcurrent that occurs when a moving object is physically stopped by a stopper or the like and an overload is applied to the motor.When the temperature rises and reaches a certain temperature range, the resistance value increases rapidly and a switching action occurs. P.T.
One set consists of a C element and a diode connected in series, and these two sets are connected in series between the switch and the motor in an antiparallel state, and the PTC element is connected to the PTC element. The above-mentioned PT
A switch circuit in a drive device, characterized in that a timer circuit is connected to cut off current to a C element.