JPH01320801A - Clutch for motor-driven telescopic antenna - Google Patents

Abstract

PURPOSE:To attain excellent durability, to keep a prescribed clutch pressure over a long period stably, to simplify the structure and to attain inexpensive manufacture by overriding a projection of a locking/escaping element and turning it while the tip of a torsion bar is deformed elastically with a clutch unlocked. CONSTITUTION:When a drive side clutch mechanism 20 is moved in a direction A by a motor power, a tip (d) of a torsion bar 28 comes to a position P1 and is inserted to a mesh part 15a. A level L1 is preset downward slightly in a figure more than a level L0. Thus, most of a torque in the direction A of the tip (d) attended with the drive of the mechanism 20 acts like a component pushing a roller 15 in the direction A linearly and the tip (d) and the roller 15 are simply locked. Thus, a follower clutch mechanism 10 receives a force in the direction A via the roller 15 and is rotated together with the mechanism 20. A rope with a rack (not shown in figure) meshing with a gear 13 is moved outward by the turning of the mechanism 10 to apply telescopic operation of the antenna (not shown in figure).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a clutch for an electric telescoping antenna suitable for an electric telescoping antenna installed in, for example, an automobile.

[Prior Art] Generally, electric telescoping antennas are configured so that when a motor is rotated forward or backward, the antenna expands or contracts. In this operation, when the antenna completes its expansion or contraction operation, an overload will naturally be applied to the motor, and if this condition is left untreated, the motor windings will be burnt out. In order to prevent such a situation from occurring, a clutch is interposed between the motor side and the antenna side, and the clutch is operated when the antenna extension or contraction operation is completed.
The coupling between the motor side and the antenna side is released.

Conventional clutches are often constructed in such a way that unevenness is provided on the joining surfaces of the driving side clutch plate and the driven side clutch plate, and the joining surfaces provided with the unevenness are pressed against each other by a compression spring.

[Problems to be Solved by the Invention] The above-mentioned conventional clutch has the disadvantage that the contact surface of the clutch plate with the unevenness is severely worn, causing a decrease in clutch pressure in a relatively short period of time, and poor durability. there were. Further, it is difficult to stably apply the pressure contact force of the compression spring to the clutch plate, and there is a drawback that a constant pressure cannot be stably maintained for a long period of time.

Furthermore, the structure is complicated, making it difficult to reduce manufacturing costs.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a clutch for an electric telescoping antenna that has excellent durability, can stably maintain a constant clutch pressure over a long period of time, has a simple structure, and can be manufactured at low cost.

[Means for Solving the Problems] In order to solve the above problems and achieve the objects, the present invention takes the following measures. That is, it consists of a driving side clutch mechanism that is rotationally driven by motor power, and a driven side clutch mechanism that rotates upon receiving rotational force from the driving side clutch mechanism and extends or contracts the antenna. The proximal end side of a torsion bar formed by bending and molding a rod-shaped spring on one side of one of the bases of the mechanism can be allowed to rotate around the axis corresponding to one twist or bend, for example, and to move in the lateral direction. The clutch mechanism is held in such a manner that its distal end side is movable toward and away from the one side surface in the periphery of the base body, and the clutch mechanism is held on the other base body of the clutch mechanism so that the relative rotational movement of both clutch mechanisms can be controlled. An engagement/disengagement element is provided that engages and disengages from the tip of the torsion bar at times.

action] By taking the above measures, the following effects occur.

That is, when the clutch is disengaged, the tip of the tone bar is not elastically deformed and rotates over the protrusion of the engagement/disengagement element, resulting in significantly less wear and tear (high durability). In addition, in the elastic deformation of the torsion bar, deformations such as ``twisting,''``bending,''``elongation,'' and ``contraction'' are comprehensively utilized, so there is little ``settling'' of the spring force caused by the torsion bar. It is possible to mutually and stably maintain a constant pressure over a long period of time.Furthermore, the structure is simple and inexpensive as it can be composed of base bodies on the driving side and driven side, a torsion bar, and an engaging/disengaging element. It can be manufactured.

[Embodiment] FIGS. 1(a) and 1(b) are perspective views showing the configuration of an embodiment of the present invention, in which (a) shows a driven-side clutch mechanism, and (b) shows a driving-side clutch mechanism, respectively. ing.

The driven side clutch mechanism 10 shown in (a) includes a base body 11 integrally molded from a material such as a hard synthetic resin and having a short cylindrical shape with a bottom, and a disengageable mechanism as referred to in the present invention attached to the inner bottom surface of the base body 11. It is composed of a roller 15 as an element. The base body 11 has a shaft hole 12 in its center, and a rope with a rack (not shown) for driving the antenna is attached to the outer surface of the peripheral wall.
It has a gear part 13 that meshes with the hook part. Further, the inner bottom surface has a roller support member 14 that rotatably supports the roller 15. The roller 15 rotates only when a certain load is applied thereto, and is mounted with a spring washer 16 interposed between it and the supporting portion JA14, for example, so that it can normally remain stationary. On the outer circumferential surface of the roller 15, an engaging portion consisting of an arcuate surface is formed along the circumferential direction, as will be described later.

The drive-side clutch mechanism 20 shown in (b), like the driven-side clutch mechanism 10, includes a disc-shaped base body 21 integrally molded from a material such as hard synthetic resin, and a disc-shaped base body 21 attached to one side of this base body 21. It is configured as a torsion bar 28. The base body 21 has a shaft portion 22 at its center, and a gear portion 23 that meshes with a motor power transmission gear (not shown) on the outer peripheral surface of the disc.
have. Further, on one side, holding pieces 24, 25, 26, and 27 for holding the torsion bar are provided. 1・
- The John bar 28 is formed by bending a round rod-shaped spring shank made of, for example, phosphor bronze as shown in the figure, and each part is held by the holding pieces 24 to 27 as follows. In other words, the proximal end a has a notch provided on its lower surface that is connected to the holding piece 2.
It is held by the holding piece 24 in a state where it is fitted into the protrusion of No. 4. Note that a torsion bar 28 is provided at the fitting portion.
This is so that the pressure contact force due to the elasticity of the material is applied.

Thus, even if an external force is applied to the torsion bar 28 in the longitudinal direction, displacement in the longitudinal direction is prevented by the above-mentioned portion. The first intermediate portion is held on the surface of the base body 21 by a holding piece 25 having a semi-cylindrical shape. Thus, even if a force acting on the torsion bar 28 causes it to float from the base surface, the above-mentioned portion prevents the torsion bar from floating. The S2 intermediate portion C is held in a groove of the holding piece 26 having a bar insertion groove. In this way, while allowing the torsion bar 28 to "twist" in the direction of arrow M, positional shift in the direction of arrow N is prevented, and the tip d, which will be described below, is positioned. The tip portion d is configured such that it can be elastically deformed in the vertical direction in the figure within the window frame of the holding member 27 having a window frame shape.
The displacement range of part 1 is held in a regulated state by a holding piece 27.

2 and 3 are side views of the drive-side clutch mechanism 20 viewed from two different directions.

As shown in FIGS. 2 and 3, the torsion bar 28 is
When an external force is applied to the tip d in the two directions of the arrows, it is elastically deformed as shown by the broken line, and when the external force is removed, it returns to the position shown by the solid line. Note that the tip d of the torsion bar 28 is
Pressurization is applied to the upper end of the inside of the window frame of the holding piece 27 at all times so that it is in contact with the upper end of the window frame at a predetermined pressure. In addition, the above external force is
The shaft hole 12 of the driven clutch mechanism 10 is fitted into the shaft hole 12 of the driven clutch mechanism 10 in the shaft column part 22 of the driving clutch mechanism 20, and the driven clutch mechanism 10 is locked. When rotated by motor power, the force is exerted by the outer circumferential surface of the roller 15, and the force is applied to region X in FIG.

Next, the operation of the embodiment configured as described above will be explained with reference to FIG. 4. When the drive-side clutch mechanism 20 is rotated by motor power, the drive-side clutch mechanism 20 moves in the direction of arrow A as shown in FIG.
The driven clutch mechanism 10, which is initially in a stationary state, relatively moves in the direction of arrow B. Torsion bar 2
The tip d having the area X of 8 is in contact with the upper end of the holding piece 27 within the window frame as described above, and therefore is at the level L1 in FIG. Therefore, the tip d is the roller 1
5, the torsion bar tip d comes into contact with the circumferential surface of the roller 15 as shown in the figure. Note that an arcuate engaging portion 15a is provided on the outer peripheral surface of the roller 15 along the circumferential direction. Therefore, the torsion bar tip d fits into one of the meshing parts 15a.

At this time, the level L1 where the tip d of the torsion bar 28 is located is set in advance so as to be slightly lower in the figure than the level LO where the center point rOJ of the roller 15 is located. Therefore, the drive side clutch mechanism 2
Most of the driving force of the torsion bar tip d in the direction of the arrow A due to the rotation of the torsion bar acts as a component that linearly pushes the roller 15 in the direction of the arrow A, and the component of the force that rotates the roller 15 is small. Therefore, the roller 15 maintains a non-rotating state, and the tip d of the torsion bar 28 and the roller 1
5 is simply locked. In this way, the driven side clutch mechanism 10 is given a force in the direction of arrow A via the roller 15, and rotates together with the driving side clutch mechanism 20.

Due to the rotation of the driven side clutch mechanism 10, the gear portion 1
The racked rope meshing with 3 is transferred outward,
An antenna extension operation is performed. When the antenna completes extension, the driven clutch mechanism 10 stops rotating. Then, the driving side clutch mechanism 20 and the driven side clutch mechanism 10 move as shown by the arrows A and B in FIG.
It exhibits a state of relative rotation in the opposite direction. However, in this case, since the torsion bar tip d and the roller 15 are in a locked state and the driven side clutch mechanism 10 is completely stopped, the driving side clutch mechanism 20
A strong force acts between the tip d of the 1-version bar and the roller 15 in the driven clutch mechanism 10. Then, the slight rotational force applied to the roller 15 is increased, and the roller 15 finally rotates around the cloth in FIG. 4. And the torsion bar tip d is the roller 15
It receives a force in the Z direction from , and moves its position to P2 while being elastically deformed to level L2. Furthermore, the drive side clutch mechanism 2
As the rotation of 0 progresses, the torsion bar tip d moves to the roller 15.
The force Z is weakened from , and the position is moved to P3 while elastically returning to level L1. In other words, the torsion bar tip d overcomes the roller 15. After that, the drive side clutch mechanism 2
When 0 rotates once, the torsion bar tip d collides with and overcomes the roller 15 again as described above, and this operation is repeated thereafter. In other words, the clutch operates and the antenna side and the motor side are disconnected.

After this condition is reached, a well-known upper limit switch is activated and the motor power is cut off.

Thus, the rotational operation of the drive-side clutch mechanism 20 is stopped,
The antenna is held in an extended state.

When the motor is reversely rotated, the drive-side clutch mechanism 20 rotates in the opposite direction to that in the above-described case. To 11
= When the tip part d of the bar collides with the engaging part 15a of the roller 15 at position P3, the roller 5
initially remains non-rotating.

Therefore, the driven clutch mechanism 10 rotates in the same direction as the driving clutch mechanism 20. Therefore, a reduction operation of the antenna is performed. When the antenna is completely reduced, the roller 1 of the torsion bar tip d is moved as in the case described above.
5 occurs, and the clutch appears to be disengaged. Thereafter, a series of operations such as cutting off the power to the motor by the lower limit switch, stopping the rotation of the drive-side clutch mechanism, and maintaining the antenna in the contracted state are performed in the same manner as in the case described above.

As described above, according to this embodiment, the torsion bar 28
Since the clutch pressure is obtained by the relationship between the roller 15 and the roller 15, the following effects are achieved. In a state in which the driving side clutch mechanism 20 and the driven side clutch mechanism 10 rotate relative to each other when the antenna extension is completed and the antenna retraction is completed, that is, in a state where the clutch is disengaged, the torsion bar tip d deforms elastically. , and performs an operation of riding over the roller 15 while rotating the roller 15. As a result, the wear on the clutch contact surface is significantly less than that of the conventional clutch due to mere pressure contact and sliding. Therefore, it is highly durable. In addition, in the elastic deformation of the torsion bar 28 made of a round bar-shaped spring material formed by bending, the entire torsion bar 28 undergoes "twisting", "bending", "stretching", and "
Since deformation such as shrinkage "2" is comprehensively utilized, the torsion bar 28 has little "1" settling, and a constant pressure can be stably maintained over a long period of time. Furthermore, since it can be composed of the base body 1.1.21, the roller 15, and the torsion bar 28, the structure is simple, the manufacturing and assembly process is easy, and it can be manufactured at low cost.

Next, modifications of each part will be explained. Figures 5 and 6
The figure shows a first modification, in which a pincushion-shaped auxiliary roller 30 is attached to the tip d of the torsion bar 28.
FIG. 3 is a diagram showing an example in which the contact ring 31 is formed on the inner bottom surface of the base body 11 on the driven side and is a contact ring 31 as an engaging/disengaging element having uneven parts (2) and (W) on its surface. Incidentally, the auxiliary roller 30 in FIG. 6 omits illustration of flanges at both ends.

In this example, a contact ring 31 is used in place of the roller 15 in the previous example, and an auxiliary roller 30 is used to reduce the frictional force with the torsion bar 28.

Therefore, compared to the embodiments described above, the degree of wear is the same. Since the annular contact ring 31, which has concave and convex portions V and W on its surface that are a series of relatively gently sloped surfaces, is arranged in an endless manner, when the clutch is disengaged, the strength of the contact ring 31 is maintained at a predetermined level. Since this clutch pressure is continuously obtained multiple times during one rotation, the antenna is excellent in its ability to maintain the extended state when the antenna is completely extended and when it is completely retracted.

FIG. 7 is a diagram showing a second modification. This example is an example in which a roller 45 corresponding to the roller 15 in the previous example is combined with the first modification shown in FIGS. 5 and 6. That is, a contact ring 41 formed similarly to that described above.
A roller 45 is disposed on one of the four parts V of the torsion bar 28, and an auxiliary roller 30 is attached to the tip d of the torsion bar 28.

According to this example, as in the modified examples shown in FIGS. 5 and 6, the action of the endless contact ring 41 allows the required clutch pressure to be continuously obtained in the state in which the clutch is disengaged. Due to its presence, the locking force, that is, the clutch pressure when the antenna is extended and retracted, becomes almost the same as in the embodiment described above. Moreover, the auxiliary roller 30 is moved from position Q1 to Q in FIG.
When moving to step 2, the auxiliary roller 30 and the convex portion W of the contact ring 41 come into contact with each other. Therefore, the impact force between the tip end d of the torsion bar 28 and the upper end of the window frame-shaped holding piece 27 is alleviated, and there is an advantage that noise caused by the impact can be reduced.

Note that the present invention is not limited to the above embodiments and modifications. For example, the rollers 15 may be provided at two locations = 15- or more, or the torsion bar = 28
Two or more may be installed symmetrically. It goes without saying that various other modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the present invention, the base end side of a torsion bar formed by bending and molding a rod-shaped spring material is fixed to one side surface of one of the base bodies of the driving side or driven side clutch mechanism, and the tip end of the torsion bar is The clutch mechanism 9 is disposed on the periphery of the base body so as to be displaceable in the direction toward and away from the one side surface, and the clutch mechanism 9 is disposed on the other base body so that the clutch mechanism 9 is disposed on the other base body at the peripheral portion of the base body. A clutch for electric telescopic antennas is provided that engages and disengages from the tip of the bar, so it has excellent durability, can stably maintain a constant clutch pressure over a long period of time, and has a simple structure and can be manufactured at low cost. can be provided.

[Brief explanation of the drawing]

1(a)(b) to 7 are diagrams showing one embodiment of the present invention, FIG. 1(a)(b) is a perspective view showing the configuration, and FIGS. 2 and 3 are drive 4 is a side view of the side clutch mechanism 20 seen from two different directions, FIG. 4 is an explanatory diagram of the operation, FIGS. 5 and 6 are diagrams showing a first modification, and FIG. 7 is a diagram showing a second modification. be. DESCRIPTION OF SYMBOLS 10... Driven side clutch mechanism, 11.21... Base body, 15... Roller (engagement/disengagement element), 20... Drive side clutch, 24, 25. 26... Holding piece, 28...・・・
Torsion bar, 30... Auxiliary roller, 31.41.
...Contact ring (engagement/disengagement element). Applicant's agent Patent attorney Takehiko Suzue N.N.

Claims (1)

[Scope of Claims] Consisting of a drive-side clutch mechanism that is rotationally driven by motor power, and a driven-side clutch mechanism that is rotated by rotational force transmitted from the drive-side clutch mechanism and extends or contracts the antenna, The proximal end side of a torsion bar formed by bending and molding a rod-shaped spring material is held on one side of one of the base bodies of the side or driven side clutch mechanism, and the distal end side of the torsion bar is held against the one side face at the periphery of the base body. The clutch mechanism is disposed such that it can be displaced in the direction of engagement and separation, and the other base of the clutch mechanism is provided with an engagement/disengagement element that engages and disengages from the tip of the torsion bar during relative rotation of both clutch mechanisms. A clutch for electric telescoping antennas.