JPH0754964Y2 - Motor drive type variable resistor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a motor drive type variable resistor for operating a rotary operation type variable resistor by a driving force (rotational force) of a motor, and more particularly to The present invention relates to a reduction gear mechanism provided in a motor-driven variable resistor.

[Prior Art] FIGS. 10 to 12 describe a conventional example of a motor-driven variable resistor of this type described in Japanese Utility Model Laid-Open No. 1-160802, and FIG. FIG. 11 is a side view of the variable resistor, FIG. 11 is a plan view of a reduction gear mechanism included in the variable resistor, and FIG. 12 is a cross-sectional view of a clutch mechanism included in the variable resistor.

In these figures, reference numeral 100 denotes a rotary operation type variable resistor as a whole, and the variable resistor 100 is a case 1 whose both ends are open.
01 and a pair of resistance boards 102 fixed to both ends of the case 101.
A bearing 103 fixed to one open end of the case 101,
A rotating operation shaft 104 rotatably supported by the bearing 103, a slider receiver (not shown) housed in the case 101 and rotating integrally with the rotating operation shaft 104, and both surfaces of the slider receiver It is composed of a slider (not shown) which is fixed and slides on the resistance boards 102.

At the other open end of the case 101, a box-shaped storage box 1
05 is fixed, and the motor 106 is fixed to the mounting surface of the storage box 105 opposite to the variable resistor 100. The rotating shaft 107 of the motor 106 is the storage box 10
The first worm 108 having a cylindrical shape is fixed to the rotating shaft 107. This first worm 108
A cylindrical first wheel 1 whose axis is perpendicular to the axis of rotation 107
The second cylindrical worm 110, which meshes with the first wheel 109 and rotates together with the first wheel 109, meshes with the second cylindrical wheel 111, the axis of which is orthogonal to the second worm 110. Cage, these first worm 108, first wheel 10
9, the second worm 110 and the second wheel 111 constitute a reduction gear mechanism.

As shown in FIG. 12, at the center of the second wheel 111, a support shaft 1 integrated by press fitting and a speed nut 112 is provided.
13 and a driving body 114 are inserted, and the rotary operation shaft 1 is inserted in a groove 115 having an oval cross section formed at one end of an inner support shaft 113.
An oval-shaped engaging portion 116 formed at the tip of 04 is inserted. In addition, the outer driving body 114 and the second wheel 1
A pad 117 made of a felt material or the like is interposed between the driving member 114 and the shaft 11, and the driving member 114 is moved toward the second wheel 111 by a spring 118 elastically mounted between the second wheel 111 and the support shaft 113. The pad 117 is urged in the direction of compression. The second wheel 111, the support shaft 113, and the driving body
The clutch mechanism is composed of 114, pad 117 and spring 118.

Next, the operation of the conventional motor-driven variable resistor configured as described above will be described.

First, the case of driving the motor 106 will be described.
The rotation force of the motor 106 is the first worm 108 and the first wheel.
It is transmitted to the second wheel 111 via 109 and the second worm 110, and the rotational speed is reduced between them. Then, when the second wheel 111 rotates, the rotational force is transmitted to the driving body 114 via the pad 117, so that the driving body 114
113 and a rotary operation shaft connected to the support shaft 113
104 rotates, a slider receiver (not shown) fixed to the rotary operation shaft 104 rotates with respect to the resistance substrate 102, and the resistance value of the variable resistor 100 is adjusted.

On the other hand, when the rotary operation shaft 104 is manually operated, the rotary operation shaft 1
Although the rotational force of 04 is transmitted to the driving body 114 via the support shaft 113, it is not transmitted to the second wheel 111 due to the slip between the driving body 114 and the pad 117, and a slider receiver (not shown) The resistance value of the variable resistor 100 is adjusted by rotating.

[Problems to be Solved by the Invention] By the way, in the conventional reduction gear mechanism configured as described above, the first worm 108 and the first wheel 109 and the second
Since the power transmission between the worm 110 and the second wheel 111 is a combination of the cylindrical worm and the cylindrical wheel (helical gear), the rotating shaft 107 of the motor 106 connected to the first worm 108 and the second wheel The first worm 108 is provided between the rotary operation shaft 104 of the variable resistor 100 connected to the wheel 111.
Therefore, a length greater than the sum of the respective radii of the second wheel 111 and the second wheel 111 is required, which causes a problem that the motor-driven variable resistor becomes large.

The present invention has been made in view of the above-mentioned prior art, and an object thereof is to provide a small motor-driven variable resistor.

[Means for Solving the Problems] In order to achieve the above object, the present invention relates to a motor-driven variable resistor in which rotation of a motor is transmitted to a rotary operation type variable resistor through a reduction gear mechanism. The reduction gear mechanism has a cylindrical first worm fixed to the rotation shaft of the motor, a cylindrical first wheel meshing with the first worm, and a cylindrical first wheel that rotates integrally with the first wheel. A second worm and a crown-shaped second wheel that meshes with the second worm are provided, and the second wheel and the rotation shaft of the motor are arranged on substantially the same line, and the second worm is provided.
A wheel is connected to the rotary operation type variable resistor.

[Operation] As described above, when the side surface worm gear in which the cylindrical second worm and the crown tooth-shaped second wheel are combined is used as a part of the reduction gear mechanism, the rotation shaft of the motor connected to the first worm is used. And the rotary operation shaft of the variable resistor connected to the second wheel can be arranged substantially on the same line.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

1 to 9 relate to an embodiment of the present invention. FIG. 1 is a sectional view of a motor-driven variable resistor, FIG. 2 is a perspective view thereof, and FIG. 3 is an exploded perspective view of the variable resistor. , FIG. 4 is an exploded perspective view of the reduction gear mechanism and the clutch mechanism, FIG. 5 is a plan view of the reduction gear mechanism, FIG. 6 is a plan view of the clutch mechanism, and FIG. 7 is a sectional view taken along line VII-VII of FIG. Figures and 8 are VIII-VI in Figure 6.
FIG. 9 is a cross-sectional view taken along line II, and FIG. 9 is an explanatory view showing a manufacturing process of a leaf spring provided in the clutch mechanism.

In these figures, 1 is a rotary operation type variable resistor,
2 is a reduction gear mechanism and 3 is a clutch mechanism as a whole, and the motor drive variable resistor according to the present embodiment is roughly configured by the variable resistor 1, the reduction gear mechanism 2, the clutch mechanism 3 and the motor 4. Has been done.

As shown in FIGS. 1 and 3, the variable resistor 1
Is a metal bearing 6 having a storage recess 5, and this bearing 6
A rotary operation shaft 7 rotatably supported by the rotary operation shaft 7, and a metal die cast driving body 8 fixed to one end of the rotary operation shaft 7.
A substrate holder 10 made of synthetic resin outsert-molded on the resistance substrate 9, a slider holder 12 made of synthetic resin arranged in a recess 11 at a rear stage of the substrate holder 10, and a light emitting element. is there
It is composed of an LED 13 and a holder 14 for holding the LED 13, and the substrate holder 10 and the rear side of the bearing 6 are positioned by utilizing pins and holes provided in both.

The rotary operation shaft 7 has a through hole 15 at the center thereof, and one end (rear stage) of the through hole 15 is formed to have a slightly larger diameter. Further, a disk-shaped collar portion 16 is integrally formed at one end of the rotary operation shaft 7, and the rotary operation shaft 7 is formed at a part of an outer peripheral edge of the flange portion 16.
An arcuate connecting portion 18 is integrally formed via a protrusion 17 extending parallel to the axis of the. On the other hand, an engaging projection 20 having a slit 19 is integrally formed at one end (rear stage) of the driving body 8, and the driving body 8 and the connecting portion 18 are appropriately fixed to each other by a fixing means,
That is, in the case of this embodiment, the pin 21 projecting from the connecting portion 18 is press-fitted into the hole 22 formed in the driving body 8 to be integrated. The driving body 8 and the collar portion 16 of the rotary operation shaft 7 which are integrated in this way are arranged in the storage recess 5, and the projection 17 abuts on the stopper projection 23 formed at the bottom of the storage recess 5. As a result, the rotation range of the rotary operation shaft 7 is restricted.

The holder 14 has a thick base 24 at its lower end, which is located in a notch 25 formed in the vicinity of the stopper projection 23 and is sandwiched by the bearing 6 and the substrate holder 10. It is fixed. In addition, a thin standing portion 26 that extends upward from the base portion 24.
Has reached the space 27 defined by the protrusion 17 between the collar portion 16 and the driving body 8 so that the rotation of the rotary operation shaft 7 is not hindered. Further, the LED 13 held by the holder 14 is located in the large diameter portion of the through hole 15, and the LED 13
The lead terminal 28 penetrates the holder 14 and is led out.

The engaging protrusion 20 of the driving body 8 penetrates a center hole 29 formed in the substrate holder 10, and the engaging protrusion 20 is engaged in the center of the slider receiver 12. Pressed into hole 30.
A slider 31 is attached to the front surface of the slider receiver 12, and the slider 31 is in sliding contact with a resistor or a current collector of the resistance substrate 9.

As shown in FIGS. 1, 4, and 5, a storage box 32 made of synthetic resin, which incorporates the reduction gear mechanism 2 and the clutch mechanism 3, is joined to the rear stage of the substrate holder 10. The bearing 6, the substrate holder 10 and the storage box 32 described above are integrated by a U-shaped frame 33 screwed to the motor 4 so as not to be separated.

A rotary shaft 34 of the motor 4 reaches the inside of the storage box 32, and a cylindrical first worm 35 is press-fitted and fixed to the rotary shaft 34. The first worm 35 meshes with a cylindrical first wheel 36, and the first wheel 36 extends in a direction orthogonal to the axis of the rotary shaft 34.
It is integrally molded in the center of 37. A cylindrical second worm 38 is integrally formed on one end of the rotating body 37,
The second worm 38 is meshed with a second toothed wheel 39 having a crown gear shape, and the first worm 35, the first wheel 36, the second worm 38, and the second wheel 39 form the reduction gear mechanism 2. I am configuring. Both ends of the rotating body 37 are axially supported by the side wall of the storage box 32 and an elastic side plate 40 facing the side wall, respectively.
Slantingly lowers the rotating body 37 (axial direction and second wheel 39
Between the first worm 35 and the first wheel 36 and the second worm 38 and the second wheel by elastically urging
It is designed to absorb the rattling caused by the backlash generated in each of the 39.

The center of the second wheel 39 is rotatably supported by a support shaft 41, and the tip of the support shaft 41 has a slit 19 of the drive body 8 at its tip.
Has been inserted inside. As is clear from FIGS. 1 and 5, the axis of the rotary shaft 34 and the axis of the support shaft 41 are substantially on the same line, that is, the rotary operation of the rotary shaft 34 of the motor 4 and the variable resistor 1 is performed. The shaft 7 is arranged substantially on the same line.

As shown in FIGS. 6 to 8, the second wheel 39 is used.
An annular groove 42 is formed in the vicinity of the outer peripheral edge of the, and an annular clutch plate 43 is rotatably fitted in the groove 42. A plurality of engaging protrusions 44 are formed on the clutch plate 43 at equal intervals in the circumferential direction.
Engagement holes 46 of the leaf spring 45 are locked to some of them. The leaf spring 45 has a plurality of arms 47 extending radially, and the engaging holes 46 are formed at the tip ends of the arms 47, respectively. Further, a disc-shaped holding body 48 is outsert-molded in the center of the leaf spring 45, and the support shaft 41 is attached to the holding body 48.
While being press-fitted into the fitting hole 49 at the center of the shaft 41, and by locking a pair of locking pieces 50 formed at the center of the plate spring 45 to the peripheral surface of the support shaft 41, the support shaft 41, the plate spring 45 and the holding The three bodies of body 48 are united. Then, the second wheel 39, the support shaft 41, the leaf spring 45 having the holding body 48, and the clutch plate 43.
The clutch mechanism 3 is composed of four members.

The step of outsert-molding the holder 48 on the leaf spring 45 will be described with reference to FIG. 9. First, as shown in FIG. 9 (a), a hoop-shaped elastic plate is pressed into a predetermined shape. At this time, two parts of the arm 47 and both locking pieces
Connect the four 50 parts in total to the hoop material. Next, the hoop material thus blank-processed is sent to a molding die (not shown), and the cavity of the molding die is filled with a molten resin to hold it as shown in FIG. 9 (b). Shape body 48. Next, by bending the base of each arm 47 and the portion to be the locking piece 50, and further cutting the portion indicated by the chain double-dashed line in FIG. 9 (b), FIG. 9 (c)
A leaf spring 45 having a holding body 48 as shown in FIG.

When assembling the clutch mechanism 3 configured as described above,
First, the clutch plate 43 is fitted into the groove 42 of the second wheel 39, and the support shaft 41 is inserted from the rear end of the second wheel 39.
Next, the fitting hole 49 of the holding body 48 is press-fitted into the tip of the support shaft 41, and the engaging holes 46 of the leaf spring 45 are fitted into the engaging protrusions 44 of the clutch plate 43.
Fit in. At this time, the length between the engagement holes 46 is determined by the engagement protrusions.
Since the length is set to an integral multiple of the length between 44 (twice in this embodiment), the leaf spring 45 can be easily connected to the clutch plate 43 by appropriately selecting a large number of engaging projections 44. it can. Further, when the holding body 48 is press-fitted onto the support shaft 41, both locking pieces are
Since the 50 is automatically locked to the peripheral surface of the support shaft 41, the holder 48
It is possible to reliably prevent the shaft from falling off from the support shaft 41. Then, when the clutch mechanism 3 is assembled in this way, the clutch plate 43 causes the arms 47 formed by bending the plate spring 45.
The elastic force is applied to the second wheel 39 so that the second wheel 39 is pressed against the second wheel 39. In this case, since the span of each arm 47 is set to be sufficiently long, a necessary and sufficient frictional force can be applied between the second wheel 39 and the clutch plate 43, and each arm 47 is bilaterally symmetrical. Since it is formed in a shape, elastic force can be applied from the leaf spring 45 to the clutch plate 43 in good balance.

Next, the operation of the motor-driven variable resistor configured as described above will be described.

First, the case where the variable resistor 1 is operated by the driving force of the motor 4 will be described. In this case, the rotational force of the motor 4 includes a first worm 35 fixed to the rotary shaft 34 thereof, a first wheel 36 meshing with the first worm 35, and the first worm 35.
It is transmitted to the second wheel 39 that meshes with the second worm 38 via the second worm 38 that rotates integrally with the wheel 36, and the speed of the rotary shaft 34 is reduced between them.
Thus, when the second wheel 39 rotates at a low speed, the clutch plate 43 fitted in the groove 42 of the second wheel 39 rotates integrally with the second wheel 39 due to the frictional force between the two. Since the leaf spring 45 connected to the clutch plate 43 and the support shaft 41 fixed to the holder 48 of the plate spring 45 also rotate integrally with the second wheel 39, the drive body 8 connected to the support shaft 41 is also rotated. It rotates in conjunction with the second wheel 39. That is, in this case, the clutch mechanism 3 is in the connected state, and the rotational force of the motor 4 is transmitted to the driving body 8 of the variable resistor 1 via the reduction gear mechanism 2 and the clutch mechanism 3.

When the driving body 8 is rotated by the driving force of the motor 4 in this way, the slider receiving member press-fitted into the engaging protrusion 20 of the driving body 8 is received.
12 rotates with respect to the resistance substrate 9, and the slider 31 of the slider receiver 12
The resistance value is adjusted according to the change in the relative position between the resistor and the resistor on the resistor substrate 9. Further, when the drive body 8 rotates, the rotary operation shaft 7 also rotates in conjunction with the rotation of the drive body 8.
Is rotatable only within a range in which the projection 17 abuts both ends of the stopper projection 23, and within the range, the LED 13 and the holder 1 can be rotated.
4 is located in a space 27 defined by the driving body 8 and the collar portion 16 and does not collide with the protrusion 17. Therefore, when power is supplied to the LED 13 through the lead terminal 28 to cause the LED 13 to emit light, the light reaches the outside through the through hole 15 of the rotary operation shaft 7, and reaches the tip of the rotary operation shaft 7, for example. It is possible to illuminate the display portion of the not-shown knob that is attached.

On the other hand, when the motor 4 is stopped and the rotary operation shaft 7 is manually operated, the rotational force of the rotary operation shaft 7 is transmitted to the slider receiver 12 via the driving body 8 to rotate the slider receiver 12. Therefore, the resistance value is adjusted. Further, when the drive body 8 rotates, its rotational force is transmitted to the clutch plate 43 via the support shaft 41, the holding body 48 and the plate spring 45, but slips between the clutch plate 43 and the second wheel 39 to cause the slip. It is not transmitted to the two wheels 39, and the clutch mechanism 3 is in the cutoff state. When the LED 13 is caused to emit light during such a manual operation, this light reaches the outside of the rotary operation shaft 7 through the through hole 15 and illuminates the display portion of the knob (not shown) as in the case of the motor drive described above. You can

As described above, in the above-described embodiment, the second gear 38 is provided with the cylindrical second worm 38 and the crown-shaped second wheel 39 that meshes with the second worm 38.
Since the rotation of 39 is transmitted to the driving body 8 (rotation operation shaft 7) of the variable resistor 1 via the clutch mechanism 3, the rotation shaft 34 of the motor 4 and the rotation operation shaft 7 of the variable resistor 1 are almost The motor drive type variable resistor can be remarkably miniaturized as compared with the conventional product in which it is possible to dispose them on a straight line and both shafts have to be significantly displaced.

Further, one end of the rotating body 37 is supported by the elastic side plate 40 integrally formed with the storage box 32, and the elastic force of the elastic side plate 40 causes the first worm 35 and the first wheel 36 and the second worm to be supported.
Since the backlash between the 38 and the second wheel 39 is absorbed, the support structure of the rotating body 37 including the first wheel 36 and the second worm 38 can be simplified.

[Advantages of the Invention] As described above, according to the present invention, since the rotation axis of the motor and the rotation operation axis of the variable resistor can be arranged substantially on the same line, the motor-driven variable resistor can be downsized. Is possible.

[Brief description of drawings]

1 to 9 relate to an embodiment of the present invention. FIG. 1 is a sectional view of a motor-driven variable resistor, FIG. 2 is a perspective view thereof, and FIG. 3 is an exploded perspective view of the variable resistor. , FIG. 4 is an exploded perspective view of the reduction gear mechanism and the clutch mechanism, FIG. 5 is a plan view of the reduction gear mechanism, FIG. 6 is a plan view of the clutch mechanism, and FIG. 7 is a sectional view taken along line VII-VII of FIG. Figures and 8 are VIII-VI in Figure 6.
A sectional view taken along line II, FIG. 9 is an explanatory view showing a manufacturing process of a leaf spring provided in the clutch mechanism, FIGS. 10 to 12 relate to a conventional example, and FIG. 10 is a side surface of a motor-driven variable resistor. FIG. 11 is a plan view of the reduction gear mechanism, and FIG. 12 is a sectional view of the clutch mechanism. 1 ... Variable resistor, 2 ... Reduction gear mechanism, 3 ... Clutch mechanism, 4 ... Motor, 7 ... Rotating operation shaft, 32 ... Storage box, 34 ... Rotating shaft, 35 ... First worm , 36 ……
1st wheel, 37 ... Rotating body, 38 ... Second worm, 39
…… Second wheel, 40 …… Elastic side plate, 41 …… Spindle.

Claims (1)

[Scope of utility model registration request] 1. A motor drive type variable resistor in which the rotation of a motor is transmitted to a rotary operation type variable resistor through a reduction gear mechanism, wherein the reduction gear mechanism is a cylindrical type fixed to a rotation shaft of the motor. First worm, a cylindrical first wheel that meshes with the first worm, a cylindrical second worm that rotates integrally with the first worm, and a second worm
A crown-shaped second wheel meshing with the worm, the second wheel and the rotation shaft of the motor are arranged substantially on the same line, and the second wheel is connected to the rotary variable resistor. A motor-driven variable resistor characterized by: