JPH04355643A - Geared motor - Google Patents

Abstract

PURPOSE:To transmit the rotation of a motor efficiently by a method wherein, when the motor rotates, a coil spring wound up by the rotation of a master moving member is wound tightly around a subsidiary moving member and connected with it to transmit the rotation of the master moving member to the subsidiary moving member. CONSTITUTION:When a switch 2 is closed, the pinion 1 and the gear 7a of a motor A is turned in a direction of an arrow and a master moving member 8, a coil spring 11, a resistance member 26 and sliding members 29 are also turned in the same direction. The sliding members 29 are expanded radially by a centrifugal force against the actuation force of an arm 30 and are brought into contact with a braking member 27 to produce a resistance. The contact resistance is applied to the other end 11b of the coil spring 11 and the one end 11a of the coil spring 11 is wound up by the master moving member 8. The diameter of the coil spring 11 is reduced and the coil spring 11 contacts with a subsidiary moving member 10 to transmit the rotary force of the master moving member 8 to the subsidiary moving member 10 completely. Thus a linking member 6 linked with a load (not shown) is driven through a transmission mechanism C and an output member B. If the motor A is stopped, the coil spring 11 is loosened and the master moving member 8 and the subsidiary moving member 10 are released. With this constitution, the rotary force can be transmitted and relieved with high efficiency.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a geared motor that can be used to drive a load having a restoring force, and more specifically, the rotation and non-rotation of the motor are used to connect and disconnect the motor, respectively. This invention relates to a geared motor equipped with a clutch.

0002

[Prior Art] It consists of a motor, an output member for driving a load with a restoring force, and a transmission mechanism interposed between them. There is a geared motor equipped with a centrifugal force clutch consisting of a displaceable clutch member and a clutched member that comes into frictional contact with the clutch member when the clutch member is displaced (for example, as shown in Japanese Utility Model Application No. 124429/1983). (similar to the one given).

In such a device, when the motor rotates due to energization and the rotation is transmitted to the transmission mechanism, in the centrifugal force clutch, the clutch member rotates and comes into contact with the clutched member due to the centrifugal force. The clutched member rotates due to friction at the contact portion, the output member is actuated, and the load is driven against the return force. On the other hand, when the motor is stopped, the clutch member is stopped and the centrifugal force is eliminated, so that the centrifugal force clutch is disengaged, and the load can be returned together with the output member by its return force.

0004

[Problems to be Solved by the Invention] In the conventional geared motor described above, rotational force is transmitted by friction caused by the centrifugal force, so slippage is likely to occur between the clutch member and the clutched member, especially when the load is heavy. The problem was that the slippage was large and the efficiency was low. In order to solve such low efficiency, if the contact area between the clutch member and the clutched member is made uneven to increase the friction there, the two will not be separated even when the motor stops, and
There is a problem in that a failure may occur in which it is impossible to restore the load.

The present invention was made to solve the problems (technical problems) of the prior art described above, and when the motor rotates, the rotational force can be applied to the load with high efficiency, while when the motor is stopped, It is an object of the present invention to provide a geared motor in which an output member can be brought into a completely free state when the load is reliably restored.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the geared motor of the present invention includes a motor, an output member for driving a load having a return force, and a transmission member interposed between them. The transmission mechanism is a geared motor having a clutch disposed therebetween that is connected and disconnected in response to rotation and stop of the motor, and the clutch is connected to the motor in the transmission mechanism. a rotatable main drive member connected to the side; a round bar-shaped driven member arranged to be rotatable relative to the drive member on the same axis and connected to the output member side of the transmission mechanism; A coil spring is provided around the driven member so as to be rotatable relative to the driven member, and has one end fixed to the driving member and a resistance member against rotation attached to the other end, and the winding direction of the coil spring is as follows: The coil spring is oriented such that the diameter of the coil spring decreases when the one end is rotated in the rotation direction of the main drive member by the motor with respect to the other end.

[0007]

[Operation] When the motor rotates, the accompanying rotation of the driving member winds up the coil spring, and the coil spring is tightened around the outer peripheral surface of the driven member, thereby integrating the coil spring and the driven member. As a result, the rotation of the main driving member is transmitted to the driven member via the coil spring. The rotation is then transmitted to the output member, and the output member is activated. On the other hand, when the motor stops, the tightening is released, and the coil spring and the driven member become separate bodies in the rotational direction. As a result, the output member becomes free.

[0008]

Embodiments The drawings showing embodiments of the present application will be described below. In FIG. 1, A is a motor, B is an output member for driving a load, and C is a transmission mechanism interposed between the motor A and the output member B.

As the motor A, a small motor known as a timer motor is used. For example, an inductor motor using a permanent magnet in the rotor is used. 1 is a pinion connected to the rotor. 2 represents a power switch, and 3 represents a power plug.

Next, as the output member B, a rack is used which can freely move forward and backward in the longitudinal direction as shown by the arrow. 5 indicates its teeth. Reference numeral 6 denotes a connecting member with a load, to which a load having a restoring force is connected. The output member B may be a gear, a pulley, or the like that rotates in place of the rack.

Next, the transmission mechanism C consists of a large number of gears 7a to 7e for coupling and deceleration, a clutch D interposed between them, and a friction transmission mechanism E. In the figure, the dashed lines connecting the teeth of the gear indicate the meshing of the teeth.

The clutch D is adapted to be connected and disconnected in response to rotation and stoppage of the motor A, and this will be explained below with reference to FIG. 2. Reference numeral 8 denotes a rotatable main moving member, which is connected to the motor side of the transmission mechanism C. In this example, it is formed integrally with the gear 7a. This driving member 8 may be formed integrally with the rotor of the motor A. Reference numeral 9 denotes a spring fitting hole provided in the main moving member 8. Reference numeral 10 denotes a driven member formed in the shape of a round bar, which is arranged so as to be rotatable relative to the main driving member 8 on the same axis. This driven member 10 is connected to the output member side of the transmission mechanism C. In this example, it is formed integrally with the gear 7b. The driven member 10 is made of polyacetal resin, for example, but may also be made of a metal material with high wear resistance. A coil spring 11 is provided around the driven member 10. The inner diameter of the coil spring 11 in the free state is formed to be slightly larger than the outer diameter of the driven member 10, so that the coil spring 11 and the driven member 10 can freely rotate relative to each other in the circumferential state. One end 11a of the coil spring 11 is fixed to the driving member 8. For example, it is fitted into the fitting hole 9 described above. The winding direction of the coil spring 11 is the other end 11b.
On the other hand, the one end 11a is the main drive member 8 driven by the motor A.
When the coil spring 11 is rotated in the rotation direction as described below,
is oriented so that the diameter decreases. As the coil spring 11, for example, a coil spring made of stainless steel wire with a circular cross section is used. A wire rod having a rectangular cross-sectional shape may be used so that the contact area with the driven member 10 increases when the diameter is reduced. The material may be piano wire.

Next, 25 is the other end 11 of the coil spring 11.
A resistance imparting mechanism is shown in which a resistance force is imparted to b against the rotation of the coil spring 11. The mechanism 25 includes a resistance member 26 attached to the other end 11b of the coil spring 11 and a braking member 27 attached to the driven member 10. First, the resistance member 26 will be explained. The member 26 is mounted so as to be rotatable relative to the driven member 10. 2
Reference numeral 8 denotes a rotating body in the member, and 29 a sliding member, which is attached to the rotating body 28 so as to be able to be displaced in the radial direction. In this example, the rotating body 28 is
The spring properties of the arms 30 apply a biasing force to the sliding member 29 toward the rotating body 28, that is, toward the inner circumferential side. Further, the sliding member 29 is formed to have a relatively wide width as shown in the figure, so that a relatively large centrifugal force is generated when the sliding member 29 rotates together with the rotating body 28. Incidentally, a separately formed weight may be attached in order to apply the above-mentioned centrifugal force. 31 is a rotating body 28
With a fitting hole drilled in the other end 11b of the coil spring 11,
are fitted. Next, the braking member 27 is formed into a circular cup shape in plan view, and its peripheral wall portion is positioned on the outer peripheral side of the sliding member 29 with a slight gap therebetween.

Next, the friction transmission mechanism E will be explained with reference to FIGS. 1 and 3. Reference numeral 15 denotes a rotatable main drive member, which is formed in the shape of a round bar and is connected to the motor side of the transmission mechanism C. In this example, it is formed integrally with the gear 7c using a hard synthetic resin material such as polyacetal resin. A separate member may be connected to the gear 7c so as to be rotatable in conjunction with the gear 7c. The material is preferably a metal with high wear resistance. Reference numeral 16 denotes a driven member, which is arranged so as to be rotatable relative to the main driving member 15 on the same axis. In this example, it is loosely fitted to the outer circumferential side of the main drive member 15. They may be placed side by side on the same axis. The driven member 1
6 is connected to the output member side of the transmission mechanism C. In this example, teeth 17 formed on the outer periphery are engaged with the gear 7d. Reference numeral 18 indicates a spring hook provided on the driven member 16. Reference numeral 19 denotes a coil spring, which is provided around the main drive member 15 so that it can rotate relative to it. The inner diameter of the coil spring 19 in its free state is slightly smaller than the outer diameter of the driving member 15, and the inner periphery of the coil spring 19 is in elastic contact with the outer periphery of the driving member 15 in the circumferential state. As the coil spring 19, for example, a coil spring made of stainless steel wire with a circular cross section is used. A wire rod having a rectangular cross-sectional shape may be used to increase the contact area with the main moving member 15. The material may be piano wire. Reference numeral 20 indicates one end of the coil spring 19, which is fixed to the driven member 16. For example, it is engaged with a spring catch 18. You can stick it there. Reference numeral 21 designates an engaging member provided at the other end of the coil spring 19, and is formed integrally with the coil spring 19 by extending the other end. The winding direction of the coil spring 19 as described above is such that the diameter of the coil spring 19 decreases when the other end is rotated in the driving direction described below with respect to the one end 20. Reference numeral 23 denotes a stopper disposed on the rotation locus of the engaging member 22.

Next, the operation of the geared motor having the above structure will be explained. In the non-operating state as shown in FIG. 1, the output member B is positioned at the return position by the return force of the load connected thereto. When switch 2 is turned on in this state, pinion 1 of motor A rotates, and gear 7
a rotates in the direction of the arrow. Along with this, the main moving member 8, coil spring 11, and resistance member 26 also rotate in the same direction. When the resistance member 26 rotates as described above, the sliding member 29 expands in the radial direction against the biasing force of the arm 30 due to the centrifugal force acting thereon. Then, it comes into contact with the braking member 27, and contact resistance is generated there. Since this contact resistance is applied to the other end 11b of the coil spring 11 as a resistance force against its rotation, the one end 11a of the coil spring 11 is wound up in the rotation direction of the main drive member 8 with respect to the other end 11b. For this purpose, coil spring 1
1 has a reduced diameter, and its inner circumferential surface is pressed against the outer circumferential surface of the driven member 10. Once friction is generated due to pressure contact between the two, the coil spring 11 is more tightly wound around the outer peripheral surface of the driven member 10 due to the friction and the force of the driving member 8 turning the one end 11a. As a result, the coil spring 11 and the driven member 10 are integrated, and the rotation of the main driving member 8 is entirely transmitted to the driven member 10 via the coil spring 11. Note that the resistance member 26 is, for example, the driven member 1.
An inertial body, for example, a weight, is attached to the coil spring 11 so as to be rotatable relative to the coil spring 11. You can also do it. In that case, the braking member 27 is naturally unnecessary.

When the driven member 10 rotates as described above, the driving member 15 of the friction transmission mechanism E rotates in the driving direction shown by the arrow in FIG. 1 via the gears 7b and 7c. When the main drive member 15 starts to rotate, the coil spring 19 that is in contact with the outer peripheral surface of the main drive member 15 starts to rotate together with the main drive member 15. In this case, one end 20 of the coil spring 19 is connected to the driven member 16.
Moreover, since the driven member 16 is connected to the output member B to which the load is connected and has a resistance force against rotation, the coil spring 19 has one end 20 and the other end rotates in the driving direction. Due to the diameter reduction, the main moving member 1
It is tightly wrapped around the outer circumferential surface of 5. As a result, the frictional force between the coil spring 19 and the main drive member 15 becomes very large, and the two become integral and rotate in the driving direction X from the initial state of (A) in FIG. 4 as shown in (B). do. As the coil spring 19 rotates, the driven member 16 also rotates together. The rotation of the driven member 16 is transmitted to the output member B via the gear 7d and the gear 7e integrally connected thereto, and the output member B moves toward the operating position in the direction of the arrow in FIG. As a result, the load connected thereto is actuated in the same direction and against its return force.

When the output member B reaches the operating position by the above-described operation, the coil spring 19 rotates until the engagement member 21 comes into contact with the stopper 23, as shown in FIG. 4C. In such a state, the main moving member 15
A slip occurs between the coil spring 19 and the output member B.
is prevented from moving excessively, and the transmission of force in the slip state prevents the output member B from returning due to the restoring force of the load. In that case, the frictional force between the main driving member 15 and the coil spring 19 is such that the coil spring 19 is rotated in the drive direction X by the friction force, and the coil spring 19 is rotated in the drive direction X by the return force of the load. The force being turned in the return direction Y, which is opposite to the force, is self-adjusted to become substantially equal. As a result, the output member B is held in the operating position without being driven beyond the operating position or returned by the restoring force of the load. The load is thus kept in operation.

The above self-adjustment will be explained. The frictional force between the main drive member 15 and the coil spring 19 is large, and the force with which the coil spring 19 is turned in the driving direction X by the main drive member 15 is greater than the force with which the coil spring 19 is turned in the return direction Y by the driven member 16. If the coil spring 19 is also large, the coil spring 19
5 and tries to rotate in the drive direction X. However, when the coil spring 19 rotates in that direction, the engaging member 21 is in contact with the stopper 23, so the coil spring 19 has one end 20 rotated in the opposite direction to the driving direction X. As a result, the coil spring 19 is loosened from being tightly wound around the main moving member 15. Then, the above-mentioned frictional force decreases. On the other hand, when the above-mentioned frictional force is small, the coil spring 19 is rotated by the driven member 15 more than the force which causes the coil spring 19 to be rotated in the driving direction
When the force of turning the coil spring 19 in the return direction Y by the coil spring 6 is large, the coil spring 19 tries to turn in the return direction together with the driven member 16. However, when the coil spring 19 turns in that direction, the engaging member 21 separates from the stopper 23, so the coil spring 1
The other end of the coil spring 9 is rotated in the drive direction X relative to the one end 20, so that the coil spring 19 is tightly wound around the main drive member 15. Then, the above-mentioned frictional force increases. Due to this operation, the frictional force is divided into a force that rotates the coil spring 19 in the driving direction X and a force that rotates the coil spring 19 in the driving direction X.
is self-adjusted so that the force turned in the return direction Y by the return force of the load is substantially equal.

Next, when it is desired to restore the load to its original state, switch 2 is opened. Then, the pinion 1 of the motor A stops rotating, the driving member 8 of the clutch D stops rotating, and no force is applied to the coil spring 11 to tighten it. When this happens, the coil spring 11 is restored by its own elasticity, and the outer peripheral surface of the driven member 10 is untightened. In other words, the clutch D is in a disengaged state. In such a state, the load returns to its original state by its own restoring force. In this case, as the load returns, the driven member 16 in the friction transmission mechanism E rotates in the return direction Y as shown in FIG.
5 also rotates together in the same direction and returns to the initial state shown in FIG. 4(A).

[0020]

As described above, in the present invention, by rotating the motor A, the clutch D is connected and the output member B is operated, and the load can be driven against the return force thereof.
On the other hand, by stopping the motor A, the clutch D is disconnected and the output member B becomes free, which of course makes it possible to restore the load.

When driving a load as described above, the state of transmission of rotational force in the clutch D is such that the coil spring 11 is tightly wound around the driven member 10 by the rotation of the main driving member 8, and the coil spring 11 and the driven member 10 are integrated. In addition, if the load is heavy and the resistance to rotation of the driven member 10 is large, the coiling of the coil spring 11 becomes tighter and the integrity of the coil spring 11 and the driven member 10 is further enhanced. There is an effect that rotational force can be transmitted with extremely high efficiency without loss due to slip between the spring 11 and the driven member 10.

Moreover, even if the coil spring 11 and the driven member 10 are integrated when transmitting rotational force as described above, when the clutch D is disengaged to restore the load, the motor A When the driving member 8 stops, the tightening force disappears, and the coil spring 11 returns to its original inner diameter due to its own elasticity, losing its integrity with the driven member 10, and the driven member 10 This has the effect of ensuring that the load becomes free and the load is restored.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of a geared motor.

FIG. 2 is a longitudinal cross-sectional view of the clutch (cross-sectional view taken along line II-II in FIG. 1).

FIG. 3 is a partially cutaway perspective view of the friction transmission mechanism.

FIGS. 4A to 4D are explanatory views of the operation of the friction transmission mechanism.

[Explanation of symbols]

A Motor B Output member C Transmission mechanism D Clutch 8 Active member 10 Driven member 11 Coil spring

Claims (1)

[Claims] [Claim 1] Consisting of a motor, an output member for driving a load having a return force, and a transmission mechanism interposed between them, the transmission mechanism is capable of rotating and stopping the motor. In the geared motor, the clutch is provided with a clutch in between, which is connected and disengaged, respectively, and the clutch has a rotatable main drive member connected to the motor side of the transmission mechanism, and a drive member that is identical to the drive member. a round rod-shaped driven member arranged to be relatively rotatable on the axis and connected to the output member side of the transmission mechanism; and a round bar-shaped driven member arranged around the driven member so as to be relatively rotatable with respect to the driven member, with one end connected to the driving member. and a coil spring that is fixedly fixed and has a rotation resistance member attached at the other end, and the winding direction of the coil spring is such that the one end is rotated in the direction of rotation of the main drive member by the motor with respect to the other end. A geared motor characterized in that the coil spring is oriented so that its diameter decreases when the coil spring is