JPH04112502A - Motor-driven variable resistance - Google Patents

Abstract

PURPOSE:To eliminate a need for a slip mechanism and to arrange a motor shaft and the operating shaft of a variable resistance on the same axis by a method wherein a protrusion is installed at a groove at the outer circumference of a reduction internal gear, a viscous substance is filled and gears are engaged only when a motor is turned by means of its viscosity. CONSTITUTION:When a motor shaft 40a is turned, a driving gear 35 is turned in the reverse direction by means of a pinion 37. Thereby, a self-propelled gear 34 is turned to the same direction as that of the gear 37. By means of the viscosity of a viscous substance 42 between a groove 34b of the self-propelled gear 34 and protrusion 38a of a case 38, the gear 34 is self-propelled to the same direction as the turning direction of the gear 37 while a holding shaft 36a is used as the center. A small gear part 34a of the gear 34 engages with an internal gear 32a at the end of an operating shaft 32. The shaft 32 is turned to the direction opposite to the turning direction of the gear 37. When the supply of electric power to a motor 40 is stopped, each gear stops turning. A driving force obtained by the viscosity of the viscous body 42 between the groove 34b of the gear 34 and the protrusion 38a of the case 38 is lost; a retainer 36 and the gear 34 are returned to a neutral state by means of a spring 41 attached to the retainer 36.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a motor-driven variable resistor suitable for manual control and remote control, which is mainly used in audio equipment.

Conventional technology The conventional technology will be explained with reference to FIGS. 3 to 6.

FIG. 3 is an exploded perspective view of the motor-driven variable resistor.
FIG. 4 is a sectional view of the same side, FIG. 5 is a partial sectional view illustrating a friction drive section which is the same essential part, and FIG. 6 is an explanatory diagram illustrating the drive part which is the same essential part.

According to the figure, reference numeral 1 denotes a mounting plate disposed facing the frame 2, and a rotary variable resistor 3 having an operating shaft 3a is mounted on this mounting plate 1, and the tip of the operating shaft 3a is A drive gear 5 is loosely fitted through a coil spring 7, and a drive body 6, which will be described later, is attached to the back surface of the drive gear 5. The frame 2 also has a side plate 2a provided with a hole 2f in the center for inserting the worm gear 4a of the motor 4, and an upper plate 2b extending perpendicularly thereto.
A supporting portion 2c is provided at the end of the upper surface plate 2b and is bent at a substantially right angle.A notched engagement recess 2c' is formed in the supporting portion 2c. A notch 2d' is also provided in the same manner, and 8.10 is a column having heads 8a and 10a, respectively.These columns 8 and 1o are inserted into holes 2g and 2h of the frame 2, respectively, and further a tubular spacer 9. Insert each, and the tip of each is attached to the mounting plate 1.
After being inserted into the corresponding holes 1a and 1b, it is fixed by tightening or the like, and is connected to the frame body 2 and the mounting hole 1. Reference numeral 15 denotes a screw that is inserted into the upper and lower small holes 2j of the frame 2 and screwed into the small hole 4b of the motor 4 to fix the motor 4 to the frame 2. 12 is a first gear body, and one end 12c is a frame body 2
is engaged with the notch 2d' of the lower plate 2d, and the other end 1
2d is inserted into the small hole 2e of the upper plate 2b of the frame, and the gear 1
The worm gear 2b is rotatably supported between the upper and lower plates 2b and 2d of the frame body in a state in which the worm gear 4a of the motor 4 is engaged with the worm gear 4a. Reference numeral 13 denotes a second gear body, one end 13d of which is supported in the small hole 21 of the frame 2, the other end 13c supported in a notched recess 2c' provided in the support part 2c of the frame 2, and wound around the spacer 11. As shown in FIG. 6, one end of the rotated spring 14 is constantly pressed inward to prevent the spring from coming off. In this state, the gear portion 13a of the second gear body 13 is connected to the first gear body 1.
The gear portion 13b is further meshed with the driving gear 5 attached to the operating shaft 3a of the variable resistor 3.

Referring to FIG. 5, details of the drive gear 5 and the disc-shaped drive body 6 made of synthetic resin or the like that is in the recess 5a on the back surface and frictionally engages with the drive gear 5 will be explained. A spacer 6a of the driver 6 is fitted on the back surface of the mounting plate 1, and a speed nut 28 is press-fitted into the tip 3b of the operating shaft 3a, so that the driver 6 is rotatably attached to the operating shaft 3a. A coil spring 7 is stretched between the drive gear 5 and the mounting plate 1, and the drive body 6 and the drive gear 5
The aim is to achieve frictional engagement with the

Next, to explain the operation of the motor-driven variable resistor mentioned above,
When the motor 4 rotates, this rotation is transferred to the worm gear 4.
a, the driving gear 5 is transmitted to the first gear body 12 and the second gear body 13, and is rotated by the gear portion 13b. Therefore, the drive body 6 that is frictionally engaged with this rotates at the same time, and the variable resistor 3
The resistance value of the variable resistor 3 is varied by rotating the operation shaft 3a of the variable resistor 3.

When manually varying the resistance value of the variable resistor, a slip is generated between the drive gear 5 and the drive body 6 by rotating the operating shaft 3a, and the torque of the variable resistor 3 and the drive gear 5 are adjusted. Frictional resistance with the driving body 6 is added to obtain an appropriate rotational torque while varying the resistance value of the variable resistor 3.

Problems to be Solved by the Invention However, in the conventional motor-driven variable resistor described above, the reduction gear is always engaged, so a slip mechanism for manual operation is essential. Further, there was a problem that if the rotational torque of the variable resistor 3 was larger than the slip torque, the motor could not drive the variable resistor 3.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a groove on the outer periphery of the internal reduction gear, and a protrusion that fits into the case with an appropriate gap, and fills the gap with grease, etc. It is filled with a viscous material, and its viscosity allows the gears to mesh only when the motor is rotating.

Therefore, according to the present invention, it is possible to omit a slip mechanism from the motor-driven variable resistor, and the rotation feel and torque can be set only on the variable resistor side. The motor-driven variable resistor can be arranged coaxially, providing a motor-driven variable resistor with an excellent space factor.

Embodiment An embodiment of the present invention will be explained with reference to FIGS. 1 and 2. 1st
The figure is an exploded perspective view illustrating the main parts of the motor-driven variable resistor, and FIG. 2 is a side sectional view of the same parts.

According to the figure, 32 is an operating shaft, and an internal gear 3 is attached to the end.
2a and the bearing portion 31 of the variable resistor main body 31.
The condition is maintained by a. 34 is a self-propelled gear,
An external gear part 34a and an internal gear part 34b having a groove on the outer periphery.
It consists of the following. Reference numeral 35 denotes a drive gear, which is integrally constructed of a small gear portion 35a and a large gear portion 35b for the purpose of deceleration. 36 is a retainer, and the holding shaft 36a
is rotatably held in the case 39 by the holding shaft 3.
6b and 36c respectively connect the self-propelled gear 34 and the drive gear 3.
5 is held rotatably. 37 is the motor shaft 40a
38 is a case, and several protrusions 38a are provided on the inner surface thereof concentrically with the holding shafts of 36a and 36b, and are connected to the outer circumferential groove 34b of the self-propelled gear 34. They are fitted with an appropriate gap, and the gap is filled with a viscous material 42 such as grease.

The case 39 is fixed to the motor 40, and the case 3
Holds 8. Note that in FIG. 2, the case 39 is omitted and the cross-sectional view is shown as being integrated with the case 38. A spring 41 is attached at one end to the center of the lower part of the retainer 36 and at the other end to the case 38, and keeps the retainer 36 neutral when the motor 40 is not rotating.

Next, to explain the operation, when the motor shaft 40a rotates, the drive gear 35 rotates in the opposite direction by the pinion gear 37.
Accordingly, the self-propelled gear 34 rotates in the same direction as the pinion gear 37. Due to the viscosity of the viscous body 42 between the groove 34b of the self-propelled gear 34 and the protrusion 38a of the case 38, the holding shaft 36c
The self-propelled gear 34 is self-propelled in the same direction as the rotational direction of the pinion gear 37, and the small gear portion 34a of the self-propelled gear 34 meshes with the internal gear 32a at the end of the operating shaft 32, and the operating shaft 3
2 in the opposite direction to the rotation direction of the pinion gear 37. When the power supply to the motor 40 is stopped, each gear stops rotating, and the groove 34b of the self-propelled gear 34 and the case 38
The driving force obtained by the viscosity of the viscous body 42 between the projections 38a of the retainer 36 is removed, and the spring 41 attached to the retainer 36 causes the retainer 36. The self-propelled gear 34 returns to the neutral state. Note that when the variable resistor 31 reaches the starting and terminal ends and power continues to be supplied, there is a method in which the motor 40 is forcibly stopped by stopping the rotation of the operating shaft of the variable resistor, and a self-propelled method, although not particularly shown. It is sufficient to set one of the methods of idle rotation between the gear 34 and the internal gear 32a of the operating shaft 32 to prevent damage to the variable resistor at the end of rotation. In the former case, consideration must be given to overcurrent to the motor.

Effects of the Invention As is clear from the above embodiments, the present invention eliminates the need for a slip mechanism to enable manual operation of the motor-driven variable resistor, and also allows the motor shaft and the variable resistor operation shaft to be coaxial. The present invention provides a motor-driven variable resistor that can be placed on top of the motor, which is cheaper and has an excellent space factor.

Furthermore, since it does not have a slip mechanism, it has the feature that the operating feel of the variable resistor and torque settings can be set only on the variable resistor side.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of a motor-driven variable resistor according to an embodiment of the present invention, FIG. 2 is a side sectional view of the same portion, FIG. 3 is an exploded perspective view of a conventional motor-driven variable resistor, and FIG. 4 is a sectional view of the same side, FIG. 5 is a partial sectional view illustrating a friction drive section which is the same essential part, and FIG. 6 is an explanatory diagram of the drive part which is the same essential part.

Claims (1)

[Claims] A case equipped with at least a motor, a pinion gear that rotates due to the rotation of the motor housed in the case, a large gear portion that meshes with the pinion gear, a drive gear that has a small gear portion integrated with the large gear portion, and the above-mentioned driving gear. A self-propelled gear that has an internal gear portion that meshes with a small gear portion and has a groove on its outer periphery; a retainer that rotatably supports the self-propelled gear and rotatably holds the drive gear; and the self-propelled gear; The pinion gear has a protrusion provided on the case that fits into the groove provided therein with a certain gap, a viscous material filled in the gap, and a spring that biases the self-propelled gear to the case. When the self-propelled gear is rotated through the drive gear, the rotation of the self-propelled gear causes the self-propelled gear to rotate around the drive gear support portion of the retainer, and the internal teeth provided on the operating shaft rotate. A motor-driven variable resistor consisting of a small gear part installed in a self-propelled gear that meshes with the gear.