JPH0328901B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a support structure for a motor, and is particularly suitable for use in a friction drive device for a rotating body that is frictionally driven by a friction wheel provided on a motor shaft. This invention relates to a motor support structure.

BACKGROUND TECHNOLOGY AND PROBLEMS Generally, in a friction drive device such as a disk drive type, a material with a relatively large coefficient of friction, such as Goyu, is fixed to at least one of two surfaces that are in contact with each other, and sufficient contact pressure is applied. The rotational force is transmitted with sufficient frictional force. However, if you do not use it for a long time, the rubber surface that was in contact with it will change over time and become locally dented, so if you use it again in this state and rotate it,
The above-mentioned dents cause vibrations in the equipment. Particularly in delicate electronic equipment such as cassette tape recorders, the above-mentioned changes over time have a subtle effect, causing worsening of wow and flutter, and causing noise and vibration.

On the other hand, if a friction wheel that is energized to apply a predetermined contact pressure is installed directly on the motor shaft,
Generally, this urging force is affected by the motor's own weight. Therefore, even if an attempt is made to limit the initial contact pressure when the motor is stationary in order to prevent the rubber from deteriorating over time, the motor's own weight will have an effect, so it is necessary to set a highly accurate and therefore reliable initial contact pressure. It is difficult to do so.

OBJECT OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and its object is to provide a motor that is supported so as to be rotationally biased by other biasing means around a fulcrum eccentric from the motor axis. The object of the present invention is to provide a support structure for a motor, which is supported so that the motor cannot rotate about the fulcrum due to its own weight.

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention includes a motor and motor support members rotatably supporting the motor via one fulcrum pin at the front and rear of the motor, respectively. One fulcrum pin is provided protruding from the motor or motor support member substantially parallel to the motor axis, and each one of the fulcrum pins is arranged at opposing positions on the left and right with respect to the motor axis. and a motor support structure characterized in that a straight line connecting the support points of each of the fulcrum pins on which the motor is supported by the motor support member substantially passes through the center of gravity of the motor. be.

By configuring as described above, the motor support structure according to the present invention prevents the motor from rotating due to its own weight supported by the two opposing fulcrums, and yet allows the motor to rotate around the fulcrums by other means. It can be rotated by biasing means.

Embodiment An embodiment in which the present invention is applied to a tape drive device of a cassette tape recorder will be described below with reference to the drawings.

First, the outline of the tape drive device will be explained with reference to FIG. This tape drive device is provided on the back side of the cassette mounting surface of the mechanical board 1. Therefore, in FIG. 1, the supply reel shaft 2, take-up reel shaft 3, and capstan 4 are projected below the mechanical board 1, and these drive shafts are supported by the mechanical board 1 and project upward. .

A motor 5 is supported on the mechanical board 1 by a motor support member 6 provided on the board 1.
A motor pulley 8 fixed to the motor shaft 7 of the motor 5 is connected to a capstan pulley 9 fixed to the upper end of the capstan 4 which also serves as a flywheel.
The capstan 4 is pressed from below to drive the capstan 4 by friction. Further, on the upper part of the mechanical board 1, there is a drive gear support shaft 10 located approximately midway between the supply reel shaft 2, the take-up reel shaft 3, and the capstan 4; A conversion gear support shaft 11 is vertically mounted at an intermediate position between the two.

At the bottom of the capstan pulley 9, a capstan gear 12 made of a wide gear is fixed to the capstan pulley 9. Further, the drive gear support shaft 10 has first and second drive gears 13 and 14.
A clutch mechanism (not shown) is interposed between these parts, and these parts are respectively movable in the direction of the rotational axis and rotatably mounted. The second drive gear 14 is coupled to the first drive gear 13 by the clutch mechanism, and the first drive gear 13 drives the second drive gear 14 to rotate on the same axis. The second drive gear 14 is configured to be able to stop rotating during this rotational drive according to the load applied thereto.

A conversion gear 15 constituted by a wide gear is rotatably attached to the conversion gear support shaft 11 so as to be movable in the direction of the rotation axis. The wide gear 15 is biased upward in FIG. 1 by a compression spring (not shown). Further, a supply reel shaft gear 16 configured as a wide gear is attached to the upper part of the mechanical board 1 of the supply reel shaft 2.
Further, a first
and second take-up reel shaft gears 17, 18 are attached.

The first drive gear 13 is always meshed with the capstan gear 12, and is moved in the direction of the rotation axis to connect the conversion gear 15 and the first take-up reel shaft gear 1.
7 and is configured to be selectively engaged with. Further, the conversion gear 15 is always meshed with the supply reel shaft gear 16 and is configured to be moved in the direction of the rotation axis. Further, the second drive gear 14 is configured to mesh with and disengage from the second supply reel shaft gear 18 by movement in the direction of the rotation axis.

On the other hand, an operation plate support shaft 19 is vertically fixed to the upper part of the mechanical board 1. And this operation plate support shaft 1
A first operation plate 21 is attached to 9 via a sleeve 20 that is slidable in the axial direction, and its tip 21a is engaged with an annular groove provided in the boss of the first drive gear 13. and is configured to move up and down together with the first drive gear 13. Further, a second operation plate 22 is attached between the sleeve 20 of the operation plate support shaft 19 and the first operation plate 21. This second operation board 22 is made of a leaf spring, and its tip 22a is connected to the conversion gear support shaft 1.
1 and is in close contact with the upper surface of the conversion gear 15.

The play button (playback button) 23 is configured to press the tip 22a of the second operation plate 22 to move the conversion gear 15 downward, and the fast forward button 24 is configured to press the tip 22a of the second operation plate 22 to move the conversion gear 15 downward. Push to move these to the lowest position, and move the first drive gear 13 to the first
It is configured to mesh with the take-up reel shaft gear 17 of. Further, the rewind button 25 is located on the first operation panel 2.
1 to move it to an intermediate position and engage the first drive gear 13 with the conversion gear 15.
It is configured to remove the rots in the round -trip position, and to restore them.

In FIG. 1, reference numeral 27 is a reproducing head provided on the back side of the mechanical board 1, and the magnetic tape (not shown) is transferred from the supply reel provided on the supply reel shaft 2 to the front part 27a of the reproducing head 27. The film passes between the pinch roller 28 and the capstan 4, and is wound onto a take-up reel provided on the take-up reel shaft 3.

Next, an outline of the tape drive operation of the tape drive device configured as described above will be explained based on FIG. 1 as well.

In the stopped state, the first and second drive gears 13,1
4 is at the highest position, the second drive gear 14 meshes with the second take-up reel shaft gear 18, and the first drive gear 13 is connected to the conversion gear 1 with a predetermined gap.
It is located above 5.

When the play button 23 is pressed in the above-mentioned stopped state,
The conversion gear 15 is pushed downward and the first drive gear 1
3 and the conversion gear 15 becomes larger, and since the motor 5 rotates in the direction a in the figure, the capstan 4 is rotationally driven in the direction b, and the capstan gear 12, the first drive gear 13, the clutch mechanism, and the second The take-up reel shaft 3 is rotationally driven in the d direction through the drive gear 14 and the second take-up reel shaft gear 18 to obtain a playback state (FWD tape drive state).

Next, when the fast forward button 24 is pressed in the stopped state, the first and second operation plates 21 and 22 are pushed down to the lowest position, and the first and second drive gears 13 and 14 are also pushed down to the lowest position. be pushed down to.
That is, the second drive gear 14 and the second take-up reel shaft gear 18 are disengaged, and the first drive gear 13 and the first take-up reel shaft gear 17 are brought into mesh. Note that the first drive gear 13 and the conversion gear 15 move while maintaining the same gap, so they do not mesh with each other. Therefore, by locking the fast forward button 24 at the forward movement position, the capstan gear 12 and the first drive gear 1
3 and the first take-up reel shaft gear 17, the take-up reel shaft 3 is rotationally driven in the d direction to obtain a fast forward state (FF running drive state of the tape).

Furthermore, when the rewind button 25 is pressed in the stopped state, the first operation plate 21 is pushed down to the intermediate position, and the first and second drive gears 13 and 14 are accordingly moved to the intermediate position. Then, the second drive gear 14 and the second take-up reel shaft gear 18 disengage, the first drive gear 13 and the first take-up reel shaft gear 17 do not mesh, and the first The drive gear 13 meshes with the conversion gear 15. Therefore, by locking the rewind button 25 in its forward movement position, the capstan gear 12 and the first drive gear 1
3. The supply reel shaft 2 is rotationally driven in the f direction via the conversion gear 15 and the supply reel shaft gear 16, and a rewinding state (REW running driving state of the tape) is obtained.

Next, details of the motor support structure will be explained with reference to FIGS. 2 to 7.

As shown in FIG. 3, cylindrical anti-vibration rubber 30 shown in FIG. 5 is press-fitted into both ends of the motor 5 and integrated with the motor 5, and its outer periphery is covered with a shield plate 31. There is. A motor rear side plate 32 is integrally attached to the boss portions of the vibration isolating rubber 30 at both ends of the motor 5 at the rear of the motor, and a front side plate 34 of a motor mounting member 33 is integrally attached to the front of the motor. . That is, the boss portion of the vibration isolating rubber 30 is formed of a toothed portion (30a) in which a radial toothed portion is formed on the circumference, and a circular portion 30b, and the side plates 32, 34 are press-fitted into the toothed portion (30a) and a circular portion 30b.
The inner diameters of the central through holes 32a and 34a are slightly smaller than the outer diameter of the circular portion 30b. When the toothed portion 30a is press-fitted, the toothed portion 30a is deformed, and the side plates 32, 34 are fixed to the toothed portion 30a, and the circular portion 30b becomes a flange and falls off from the circular portion 30b as if inserted into an annular groove. This will prevent you from doing so. Also, motor rear side plate 3
A fixing pin 35 is provided at a predetermined position of 2, which is integral with this side plate 32 and is substantially perpendicular thereto. On the other hand, the motor mounting member 33 also has a rear connecting plate substantially parallel to the front side plate 34 on the rear side, and this rear connecting plate 36 is integrally connected to the front side plate 34 through a connecting member 37 in a U-shape. ing. As described above, with the motor rear side plate 32 and the front side plate 34 fixed to the anti-vibration rubber, the rear connecting plate 36 is disposed on the outside of the motor rear side plate 32 and has a semicircular engagement groove 36c. The engaging piece 36a is the fixing pin 35
is engaged with. And the through hole 36b of the connecting plate 36
The motor rear side plate 32 and the motor mounting member 33 are connected by screwing the screws 38 that pass through them into the female screw holes 32b of the motor rear side plate 32, and the motor 5 is connected to these members and the rigidity as shown in FIG. The fixing pin 35 is approximately parallel to the motor shaft 7. Note that the motor front side plate 34
On the left side of the arm 39, an arm 39 projects in a substantially horizontal direction, and a spring receiver 40 is provided at the tip of the arm 39. Also, a through hole 41 is provided in the corner.

As shown in FIG. 3, the motor support member 6 is composed of a fixing member 43 fixed to the mechanical board 1 and an adjustment plate 44. The fixing member 43 includes a horizontal member 45 bent at right angles on the right side, and a leg portion 46 on the right side that supports this horizontal member 45 on the mechanical board 1.
, a substantially horizontal protruding member 47 protruding from the rear end of the horizontal member 45 at right angles to the motor side, a short horizontal member 48 on the left side, a leg portion 49 on the left side supporting this, and horizontal members 45 on the left and right sides. , 48 and a connecting member 50 that connects them. The fixing member 43 supports the motor 5 integrated with the motor mounting member 33, and is fixed at a predetermined position on the mechanical board 1 by screws inserted through the screw holes 51 of the legs 46, 49. A through hole 52 into which the pin 35 is inserted is formed in the protruding member 47 at a position corresponding to the fixing pin 35 of the motor rear side plate 32, and an L-shaped notch is formed in the front side of the horizontal member 45. A hole 53 is provided. Further, two elongated holes 54 and 55 are formed in the left leg 49 at the top and bottom, and a threaded hole 57 into which an adjustment screw 56 is screwed is provided approximately in the center of the elongated holes 54 and 55. A large opening 58 is formed into which the arm 39 of the motor front side plate 34 can fit.

A through hole 60 through which the motor shaft 7 and motor pulley 8 pass is provided in the center of the adjustment plate 44, and a through hole 41 in the motor front side plate 34 is provided at the corner.
At a position corresponding to , a fixing pin 61 that is fitted into the through hole 41 is provided substantially perpendicularly and integrally with the side plate 34 . On the right side, there is a vertical elongated hole 53a of the L-shaped notch hole 53 of the horizontal member 45.
A guide piece 62 with a rectangular cross section that is fitted into the elongated hole 53a and is slidable in the elongated hole 53a is protruded almost horizontally. A protrusion 63 is provided. Further, on the left side, two guide pieces 64, 65 having a rectangular cross section are fitted into the long holes 54, 55 and slidable at positions corresponding to the long holes 54, 55 of the leg portion 49.
is protruded almost horizontally.

Next, in order to attach the motor 5 to the motor support member 6, the compression coil spring 6 is attached to the guide piece 62 of the adjustment plate 44.
6, and fit the guide pieces 62, 64, 65 into the corresponding elongated holes 53a, 54, 55, respectively. The motor 5 integrated with the motor mounting member 33
Adjustment plate 44 and motor support member 6 fixing member 43
The fixing pins 35 and 61 are inserted into the corresponding through holes 52 and 41 by using the elastic force of the protrusion members 47 to slightly open the protrusion members 47. and adjustment screw 5
6 into the screw hole to adjust the motor pulley 8 to a predetermined position. On the other hand, the arm 39 of the motor front side plate 34
By setting a predetermined tension coil spring 67 between the spring receiver 40 and the through hole 51 of the leg portion 49, the assembly is completed as shown in FIG. At this time, fixing pin 6
1 is substantially parallel to the motor shaft 7. That is, the motor 5 is integrated with the motor mounting member 33 and rotatably supported on the motor support member 6 via fixing pins 35 and 61, and is further pivoted about the fixing pins 35 and 61 by a tension coil spring 67. Forced to rotate.

As shown in FIG. 9B, the fixing pins 35 and 61 are located at opposite positions inclined at approximately 45 degrees to the left and right with respect to the motor axis O, and are arranged at equal distances l from the axis O, respectively. There is.

Next, the capstan pulley 9 will be explained based on FIG.

The capstan 4 is rotated by being supported by a bearing 69 fixed on the mechanical board 1. The capstan pulley 9, which is disc-shaped and has an annular recess formed in the middle part, is fixed to the upper end of the capstan 4 as described above, and the wide capstan gear 12 is fixed to the lower part of the capstan pulley 9. . The capstan gear 12 is rotatably driven together with the capstan pulley 9 while being pivotally supported on the outer peripheral surface of the bearing 69. On the lower surface side of the outer periphery of the capstan pulley 9,
An annular rubber member 70 whose contact surface is formed into a gentle conical shape is fixed, and the contact surface of the motor pulley 8 that is pressed against this surface is also formed into a conical shape with the same inclination angle. Further, fixed to the annular recess of the capstan pulley 9 is an annular rotor member 72 made of a magnetic material and having a large number of teeth 71 formed at the same pitch in the radial direction on its inner surface.

On the other hand, on the fixed side, also in the annular recess,
Teeth 73 with a pitch corresponding to the teeth 71 on the opposing surface while maintaining a predetermined gap with the teeth 71 of the rotor member 72
A stator member 74 made of a magnetic material and formed with
is provided. And this stator member 74
is provided with an annular magnet 75,
This magnet is magnetized, for example, with an N pole on its upper surface and an S pole on its lower surface, forming a magnetic path between the rotor member 72 and the stator member 74. Therefore, during rotation, the change in magnetic flux between the uneven portion formed by the teeth 71 on the rotor side and the uneven portion formed by the teeth 73 on the stator side is extracted as an output signal, and is used as a frequency generator. Speed detection is now being performed. The stator member 74 is integrally coupled with a support plate 77 (see FIG. 1 for the shape) via a center member 76, and is fixed to a support 78 vertically provided on the mechanical board 1 with screws 79.

Further, reference numeral 80 is made of Teflon or the like and has a thread provided on the outer periphery, and a conical recess 8 at the center of the shaft.
This recess 80 is a pivot bearing in which 0a is formed.
a supports the conical top 4a of the capstan 4, holds the stator side in the correct position with respect to the axis of the capstan 4, and reduces the gap between the teeth 71 of the rotor member 72 and the teeth 73 of the stator member 74. It is held correctly over the circumference. That is, to assemble the stator section, the inner surface 82 of the circular recess of the stator section is inserted using the outer circumferential surface 81 of the circular boss at the center of the capstan pulley 9 as a reference plane, and the support plate 77 is set with the screws 79. After that, when the pivot bearing 80 is screwed in, the conical recess 80a of the pivot bearing 80 follows the conical top 4a of the capstan 4, so the pivot bearing 80 is screwed in.
The axial center of 0 is precisely aligned with the axial center of the capstan 4. Therefore, the stator member 74, which is integral with the pivot bearing 80, is also finely adjusted together with the central member 76 and the support plate 77 so as to coincide with the axis of the capstan 4.

Next, the effects of the motor and motor pulley configured and supported as described above will be explained.

In FIGS. 9A and 9B, the motor 5 (including the motor mounting member 33 integrated therewith) is rotatable at the front by the fixing pin 61 and at the rear by the fixing pin 35, respectively. is supported by. Therefore, the loads shared by the fixing pins 61 and 35 out of their own weight W are W ₁ and W ₂ , respectively.
As shown in FIG. 9B, the motor 5 is rotated clockwise at the front with a moment W ₁ m ₁ and rotated counterclockwise at the rear with a moment W ₂ m ₂ . However, since the fixing pins 35 and 61 are located at opposite positions that are inclined with respect to the motor axis O, and are equidistant l from the motor axis O, m ₁ = m ₂ , and the motor 5 is supported by the motor. Since the straight line connecting the support points R and S of the pins 35 and 61 supported by the member 6 passes approximately through the center of gravity of the motor 5 in FIG. 9A, W ₁ =W ₂ =W/2. Therefore, since W ₁ m ₁ =W ₂ m ₂ , the motor 5 does not rotate due to its own weight. However, since the motor 5 is rotatably supported by the fixed pins 35 and 61, it can be rotated about these pins 35 and 61 by external force.

Next, the friction drive by the motor pulley 8 will be explained. As described above, in FIG. 6, the arm 39 of the motor front side plate 34 is urged downward by the tension coil spring 67. As shown in FIG. Therefore, the motor 5, that is, the motor pulley 8 is urged to rotate in the g direction about the fulcrum 61 in FIG. 10, and is pressed against the rubber member 70 of the capstan pulley 9. With this initial contact pressure, the motor pulley 8 moves in the same direction a as shown in Figure 1.
When is rotated, the motor pulley 8 attempts to rotate the capstan pulley 9 in the direction b by a rotational force P corresponding to this initial contact pressure, so the contact surface of the motor pulley 8 has a rotational force P corresponding to the rotational force P. reaction force
P' acts in the i direction opposite to b. This reaction force
Since P′ is the force that tries to move the motor shaft 7 in the i direction, the product of its tangential component P″ and the radius l
With a moment of P″・l, the motor pulley 8 is
In Figure 0, it is rotated about a fulcrum 61 in the direction of arrow g. That is, this rotational force causes the motor pulley 8 to be pressed against the capstan pulley 9 with a contact pressure greater than the initial contact pressure, so that the rotational force P becomes even larger. As the frictional force increases through this process, the capstan pulley 9
When the load reaches , the capstan pulley 9 starts rotating and enters a steady operating state.

In other words, even if the initial contact pressure is small, if it is the minimum necessary to prevent slipping, the motor pulley 8 will automatically bite into the contact surface of the capstan pulley 9, so the contact pressure will gradually increase and the pressure will be adjusted to match the load. As the contact pressure increases, the capstan pulley 9 is driven to rotate. For example, the cassette tape recorder of this embodiment, which conventionally required a contact pressure of 90 to 100 g, now requires an initial contact pressure of 20 to 30 g. Note that the angle α in Figure 10 is 120 to 150.
degree is the most effective.

Furthermore, in the present invention, as described above, since the motor is supported so as not to rotate under its own weight, the initial contact pressure is not affected by the motor's own weight. Therefore, since a highly accurate initial contact pressure can be applied, this initial contact pressure can be reduced to the necessary minimum.

Next, another adjustment function of the fine adjustment mechanism will be explained. Adjustment plate 4 of motor support member 6 shown in FIG.
4 has its arms 62, 64, 65 slidably supported in the elongated holes 53a, 64, 65 of the fixed member 43 of the motor support member 6, respectively, as described above, and the left It is configured so that it can be finely adjusted horizontally to the left and right (in the y direction) using an adjustment screw 56. On the other hand, this adjustment plate 44
The motor 5 is connected to the motor mounting member 33 by the pin 61 fixed to the adjustment plate 44 as described above.
It is rotatably supported along with the shaft. Therefore, the adjusting screw 56 moves the adjusting plate 44 from the position shown by the solid line in FIG. 7 to the rightward position shown by the dashed line.
When is slightly moved, the fixing pin 61 moves horizontally to the right by this fine adjustment amount. However, as described above, the motor 5 is supported by the fixed pins 35 and 61, and the rear fixed pin 35 does not move. Therefore, when the support point S of the front fixed pin 61 moves, the motor 5 is supported by the rear fixed pin 35. It will rotate to the right around the support point R. Therefore, the center shaft of the motor also rotates in accordance with this amount of fine adjustment. For example, the motor shaft center is offset by x with respect to the center Q of the capstan pulley 9, and the motor pulley 8 is set at this eccentric position. Ru. That is, after assembly, the magnetic tape can be run, and the motor pulley 8 can be set at a position that provides the best wow and flutter value by adjusting the motor pulley 8 left and right with the adjustment screw 56 while looking at the pointer of the measuring instrument.

Effects of the Invention As explained above, according to the motor support structure of the present invention, the motor is supported by two fulcrum pins located at opposite positions on the left and right with respect to the motor axis at the front and rear of the motor. Since the straight line connecting these supporting points passes through the center of gravity of the motor, the motor does not rotate about these fulcrum pins due to its own weight.
However, since the motor is supported by the two support pins as described above, it can be biased to rotate around these fulcrum pins by other biasing means.

Therefore, when this motor support structure is used in a friction drive device for a rotating body in which rotational force is applied to a friction wheel provided on a motor shaft to bring it into contact with a driven rotating body to transmit rotational force, this Since the weight of the motor does not affect the biasing force at all, this biasing force can be set to the necessary minimum value with high accuracy.

[Brief explanation of drawings]

The figures show an embodiment in which the present invention is applied to a tape drive device of a cassette tape recorder. 3 is an exploded perspective view of the same figure as above, FIG. 4 is a perspective view of the motor support member in FIG. 2 with the fixing member removed, and FIG. 5A is a perspective view of the motor. A vertical cross-sectional view of the anti-vibration rubber, Figure 5B is B in Figure 5A.
-B line arrow sectional view, Figure 5C is C-C in Figure 5A
6 is a sectional view taken along the - line in FIG. 2, FIG. 7 is a sectional view taken along the - line in FIG. 2, and FIG.
The figure is a vertical sectional view of the capstan pulley, and Figures 9A and 9B are principle explanatory diagrams of the motor support structure.
Figure A is a side view of the motor support structure, Figure 9B is a front view of the same as above, Figure 10 is a diagram explaining the principle of the friction drive unit and is a front view of the drive unit seen from the motor pulley side, Figure 11
The figure is an explanatory diagram of the fine adjustment mechanism and is a schematic top view of the motor support structure. In addition, in the symbols used in the drawings, 5...Motor, 6...Motor support member, 8...Motor pulley (friction wheel), 9...Capstan pulley (rotating body), 33
...Motor mounting member, 35...Fixing pin (fulcrum pin),
43...fixing member, 44...adjustment plate, 61...fixing pin (fulcrum pin).

Claims (1)

[Claims] 1 A motor and a motor support member rotatably supporting the motor via one fulcrum pin at the front and rear of the motor, each of the one fulcrum pin being approximately aligned with the axis of the motor. protruding from the motor or the motor support member in parallel, and each of the one fulcrum pin is disposed at opposite positions on the left and right with respect to the motor axis, and the motor is supported by the motor support member. A support structure for a motor, wherein a straight line connecting the support points of each of the fulcrum pins substantially passes through the center of gravity of the motor.