JPS60116956A - Wire stretch absorbing mechanism - Google Patents

Abstract

PURPOSE:To prevent the tooth skipping phenomenon of the ratchet teeth by providing a cam means separating a flange and the first pulley from each other when rotating the first and the second ratchet teeth in the engaging direction. CONSTITUTION:When a shaft 3 is rotated in the arrow A direction, both taper faces 15, 16 of lugs 13, 14 tent to be stranded each other before the notched section 11 of a flange 4 is coupled with a lug 12. Therefore, an energizing force in the arrow D direction is applied to the first pulley 5, and the first pulley 5 and the second pulley 6 are moved in the D direction against the energizing force of a wave washer 8 in the arrow C direction. This shift is performed while the flange 4 is rotated by the backlash against the first pulley 5. Accordingly, the second pulley 6 can be hardly moved in the axial direction, and the tooth skipping phenomenon can be prevented almost reliably.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an absorption mechanism (referred to as an absorption mechanism). More specifically, the present invention relates to an absorption mechanism that has been improved to prevent tooth skipping in an absorption mechanism that utilizes unidirectional engagement of ratchet teeth.

2. Description of the Related Art Conventionally, some remote control systems that employ flexible wires as power transmission means incorporate an absorption mechanism for absorbing permanent elongation that occurs in the wires. As a bending absorption mechanism, for example, as shown in FIG.
51) that automatically absorbs the elongation of the wire when operating the wire has been proposed. Such a wire drive device locks both ends of a wire (51) routed in a closed loop on its surface, and connects one end (52) of the wire (51) to the surface of the wire (51).
It has a drive pulley (54) for winding up and unwinding the other end (53), thereby circulating the loop of wire (51) in either direction. driving boo v
(54) is divided into a first pulley (55) and a second pulley (56).
6) can be relatively rotated only in the direction to shorten the wire loop, and such relative rotation can absorb the elongation of the wire. In order to rotate only in such a specific direction, the first boo') (55) and the second
A first ratchet tooth (57) and a second ratchet tooth (58) are provided on adjacent sides of the pulley (56), respectively.
) is engraved, and the 11th-! J (55) and 21st-
It is allowed to move in the axial direction relative to the IJ (56), and a wave washer (
59) etc. have been adopted.

The absorption mechanism having such a configuration is, for example, a first boot U.
(55) A shaft (
The loop of the wire (51) can be driven in either direction by rotating the wire (51) in the direction of the arrow (N or (B). Furthermore, the ratchet teeth (57), (
When the shaft (60) is rotated in the direction in which the shaft (58) idles (direction of arrow (B) in FIG. 5), the elongation of the wire can be absorbed.

However, if the load on the wire (51) driven by the drive pulley (54), such as sliding resistance in a driven device, becomes large, when rotating in the direction of arrow (A), which is the original meshing direction, In this case, the ratchet teeth (57) and (58) may slip, resulting in a tooth skipping phenomenon. This tooth skipping phenomenon causes the wire, which has absorbed the elongation and recovered its tension, to become loose again. Furthermore, when the tooth skipping phenomenon occurs repeatedly, the tooth tips of the ratchet teeth (157) and (58) are worn, making the tooth skipping phenomenon even more likely to occur. As a result, the absorption mechanism becomes unable to fulfill its original role.
Instead, there is a problem in that it causes the wire to become loose.

On the other hand, in recent years, there has been a trend to reduce the tooth profile of the ratchet teeth (57) and (58) in order to reliably absorb even the slightest elongation of the wire, which makes the tooth skipping phenomenon more likely to occur. Therefore, appropriate measures to prevent the tooth skipping phenomenon are increasingly desired these days.

The inventors of the present invention have conducted extensive research in order to meet the above-mentioned demands, and as a result, have developed a casing, a shaft rotatably provided within the casing, a flange fixed to the shaft, and the flange. is rotatably and axially movably housed in the casing so as to be adjacent to the casing, is connected to the flange so as to transmit torque so as to have play in the rotational direction, and is located on the side opposite to the flange. a first pulley having a first ratchet tooth; and a second ratchet tooth that is rotatably and axially movably housed in the casing so as to be in instant contact with the first pulley, and that can mesh with the first ratchet tooth. a second pulley having a second pulley; an elastic means for urging the second pulley toward the first pulley; and when the flange is rotated in a direction in which the first ratchet teeth and the second ratchet teeth mesh with each other, cam means for biasing the flange and the first pulley in a direction to separate them from each other; and cam means having both ends locked to the outer peripheries of the first pulley and the second pulley, respectively, and wound around each other in opposite directions. When adopting a wire elongation absorption mechanism having a power transmission wire, the inventors discovered the completely new fact that the tooth skipping phenomenon can be significantly reduced with a simple structure, and have completed the present invention.

Next, the absorption mechanism of the present invention will be explained with reference to the drawings.

FIG. 1 is a front view showing an embodiment of the absorption mechanism of the present invention (however, the housing is omitted), FIG. 4 is an enlarged sectional view taken along the line (Y)-(Y) in FIG. 1, respectively.

In Figures 1 and 2, (1) is a housing holder, and the housing (1) is a bottomed cylindrical casing (2).
) is fixed. Inside the casing (2) is a shaft (
8) is rotatably provided. One end (3
&) is combined with, for example, a crank type handle (3b). Therefore, it is projected outward from the housing (1). A cylindrical flange (4) with a bottom is attached to the shaft (8) so as to be concentric with the shaft (8), and is fixed by, for example, welding.

A first pulley (5) and a second pulley (6) are fitted on the outer periphery of the shaft (8) so as to be adjacent to the flange (4), respectively, so as to be rotatable and movable in the axial direction in that order. There is.

A wave washer (8) is inserted between the second pulley (6) and the casing (2), so that the second pulley (6) and the first pulley (6) are
It is constantly pressed in the a) direction.

The side surfaces adjacent to each other of the first pulley (6) and the twenty-first pulley (6) have first ratchet teeth (9) and second ratchet teeth, respectively.
Ratchet teeth (10) are formed. The first ratchet tooth (9) and the second ratchet tooth) are the first pulley (
6) mesh with each other when rotated in the direction of arrow (4), and idle when the first pulley (6) is rotated in the direction of arrow (B).

A fan-shaped notch (lυ) is formed along the periphery of the flange (4).A fan-shaped notch (lυ) is formed along the periphery of the flange (4).A fan-shaped notch (lυ) is formed along the periphery of the flange (4). ) is provided on the protrusion. The opening angle of the notch θη is larger than the opening angle of the protrusion (b), so there is some play in the rotational direction when the two are engaged.

The fan-shaped notch (b) and fan-shaped protrusion (b) shown in FIG.
In addition, conventionally known braking means may be employed.

Note that the flange (4) and tJs in the absorption mechanism of the present invention
The connection of the first pulley (5) is not limited to the combination of the notch (river and protrusion (B)), but may also be a combination of an arc-shaped long hole and a pin that can be engaged with the long hole, etc. Any torque transmission means having play in the rotational direction can be used.

As shown in detail in FIGS. 6 and 4, a first cam projection is provided on the end surface of the flange (4) adjacent to the first pulley (5). A second cam projection (B) is provided on the first pulley (6) so as to be continuous with the projection (B). to the first cam protrusion) and to the second cam protrusion)
When rotating the flange (4) in the direction in which the ratchet teeth (9) mesh with each other, that is, in the direction of arrow (A),
(tapered surfaces that extend in the circumferential direction so as to ride on each other)
, 0 groans, respectively. The first cam projection (b) and the second cam projection (b) constitute a cam means.

As shown in Fig. 172, both ends of the wire (51) are locked to the first pulley (6) and the second pulley (6), similar to the conventional absorption mechanism (for example, the one in Fig. 5). and wrapped around it.

FIG. 2(B) shows a conventionally known balance spring.

Next, the operation of the absorption mechanism constructed as described above will be explained.

In Figure 2, the shaft (8) is rotated in the direction of the arrow (A).
Before B) engages, the cam protrusions (B), NI) and NI) try to ride on each other. Therefore, the first fu-! A biasing force in the direction of arrow (D) is applied to j (5). As a result, the first pulley (6) and the second pulley (6) move in the direction of arrow (D) against the urging force of the wave washer (8) in the direction of arrow (0). Such movement takes place while the flange (4) is rotated by the amount of play relative to the first pulley (5).

When the shaft (8) is further rotated, the notch θυ and the protrusion (B) engage with each other with the elongation-absorbing clearance (field) becoming smaller, and the first pulley (5) is rotated in the direction of the arrow (A). .

As a result, the second pulley (6) is hardly able to move in the axial direction, and the tooth skipping phenomenon is almost certainly prevented. In that case, the height of the cam protrusions (B), (2) or the distance of movement of the pulleys (5), (6) caused by the engagement of the cam protrusions (B), (2) is the elongation absorption clearance shown in Figure 1. It is preferable that the height be larger than the height H) of the ratchet teeth (9) and (6) subtracted from the height H) of the ratchet teeth (9) and (6). This reliably prevents the tooth skipping phenomenon.

Furthermore, when the ratchet teeth (9) and (2) rest on each other, the axial pressing force between the ratchet teeth (9) and (2) increases by an amount corresponding to the amount of deflection of the wave washer (8). . Therefore, the tooth skipping phenomenon is even less likely to occur.

The shape of the cam means in the absorption mechanism of the present invention is not limited to that shown in FIGS. 6 to 4; for example, the cam on either side may be a groove having a tapered surface. Further, instead of a tapered surface, it may be an arcuate surface or other convex or concave surface. That is, the cam means in the present invention is a means for urging the first pulley (5) toward the second pulley (6) when the flange (4) is rotated in the direction in which the ratchet teeth (9) and (uΦ) mesh. Good to have.

In the embodiment of the absorption mechanism shown in Fig. 1, only one set of protrusions (b) and (b), which are cam means, are provided, but when two to six sets are arranged at equal intervals in the circumferential direction, is preferable because when the cam protrusions DB) and 04 ride on each other and separate the first pulley (5) and flange (4), the urging force for separation can be made almost uniform in the circumferential direction.

The positions of the cam protrusions) and (6) are not particularly limited, but they should be provided in positions where the protrusions (B) and notches (11) come into contact with each other before they completely ride on each other. This is preferable because it is easy to rotate the flange (4) in the direction of arrow (B) to disengage the cam projections (1B) and O→.

In addition, in the embodiment of the absorption amount tyt shown in No. 2114, the shaft (8) is passed through the curve of the housing (1) and the casing (2), and the first boot (5) and the second
Although pulleys (6) are respectively provided on the shafts (8), the absorption i-structure of the invention is not limited to such a case. Each pulley (6), (a) is in direct sliding contact with the inner surface of the housing (1) or casing (2), or indirectly by a fixed shaft protruding from the casing (2) or the like. 2) It suffices if it is rotatably and axially movable.

As described above, the wire elongation absorbing mechanism of the present invention can significantly reduce the tooth skipping phenomenon with a simple structure, and its practical value is extremely large.

[Brief explanation of the drawing]

Fig. 1 is a front view showing one embodiment of the wire elongation absorption mechanism of the present invention (however, the housing is omitted);
The figures are a sectional view taken along the line (1)-00 in Figure 1, Figures 6 and 4.
The figures are an enlarged sectional view taken along the line (Y)-(Y) in FIG. 1, and FIG. 5 is a longitudinal sectional view showing an example of a conventional wire elongation absorption mechanism. (Main symbols in the drawing) (2): Casing (8): Shaft (4) = Flange (5): First pulley (6): Second pulley (8): Wave washer (9): To the first ratchet tooth ): 22nd check tooth (B): Notch (B): Protrusion 03): 1st cam protrusion θX: 2nd cam protrusion K (1 (+): Tapered surface (51): Wire thread): Elongation absorption clearance (H): Ratchet tooth height Patent applicant Nippon Cable System Co., Ltd. Figure 2 Block 1 Figure 8 x Figure 3 Tail 4 Figure 5 (2) 1

Claims (1)

[Scope of Claims] 1. A casing, a shaft rotatably provided in the casing, a flange fixed to the shaft, and a shaft rotatably provided in the casing adjacent to the flange in the axial direction. a first boot that is movably housed in the first boot, is in torque-transmittable communication with the flange so as to have play in the rotational direction, and has first ratchet teeth on a side surface opposite to the flange; The first
a second pulley having second ratchet teeth that can mesh with the ratchet teeth; elastic means for biasing the second pulley toward the eleventh side; a cam means for biasing the flange and the first pulley in a direction to separate them from each other when the teeth are rotated in a direction in which the teeth mesh with each other; A wire elongation absorption mechanism having a power transmission wire wound in opposite directions to each other. 2. The cam means includes a first cam protrusion formed on an end surface of the flange and having a tapered surface extending in the circumferential direction;
a second cam protrusion formed on the side surface of the first boob and having a tapered surface extending in the circumferential direction;
(f) A wire elongation absorption mechanism according to claim 1.