JPS6261813B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a ratchet mechanism that transmits rotation in one direction, and specifically to a ratchet mechanism in which at least one of the members that come into contact with each other is made of synthetic resin. For ratchet mechanisms used in devices with relatively small loads such as timer devices and music boxes,
Using parts made of synthetic resin has various advantages such as a reduction in the number of parts, ease of assembly work, and reduction in processing costs. Several ratchet mechanisms have already been proposed in which rotating members, transmission pieces, etc. are made of synthetic resin. For example, the ratchet mechanism disclosed in Japanese Utility Model Publication No. 55-34342 can be expected to have the above merits, but problems still remain. This is because there is only one engagement portion between the rotating member and the gear, so when rotation is transmitted, a load is applied to only one engagement portion of each other, and unbalanced loads are applied to both the driving side and the driven side. Next, although Japanese Utility Model Publication No. 56-17871 discloses a ratchet mechanism having a plurality of elastic arms, since the engagement between the gear and the elastic arms is at one place, as in the above example, The problem of unbalanced loads remains. In addition, the distance between, for example, a transmission piece provided on the rotating body made of synthetic resin and an engaging portion that engages with the transmission piece must be set wide in terms of strength. Moreover, in terms of strength, each shape has to become thick and large. Therefore, a ratchet mechanism using parts made of synthetic resin has the drawback that it is difficult to make the rotating body thin and small in diameter, and fine steps cannot be set. SUMMARY OF THE INVENTION An object of the present invention is to provide a ratchet mechanism which is small in size and has a small number of parts, which takes advantage of the above-mentioned advantages and eliminates all of the above-mentioned disadvantages. The object of the present invention is to provide a rotating member made of synthetic resin, a rotating member provided coaxially with the rotating member,
In a ratchet mechanism having a rotating body, a part of which engages with the rotating member, a shaft hole portion having a shaft hole is formed in the center of the rotating member, and the shaft hole portion is connected to the outer peripheral portion by equally spaced radial rods. A stepped portion is formed in the shaft hole and a part of the radial rod outside of the shaft hole, and the space that passes through the radial rod in the upper and lower sides has an engaging portion with a free end on the inside and an engaging portion on the outside. A transmission piece is provided integrally with the rod, and the shaft of the rotating body that fits into the shaft hole has a plurality of protrusions at equal intervals that engage with the engagement portion, and a wavy fin that fits into the step portion. This is achieved by a ratchet mechanism in which the transmission pieces and the protrusions are integrally provided, and the numbers of the transmission pieces and the projections are set such that one is a non-integral multiple of the other and has a common divisor. According to the ratchet mechanism of the present invention, the rotating member and the rotating body engage with each other at equal intervals and in a plurality of cylinders, so there is no fear of unbalanced loads being applied to them during rotation transmission. In addition, the fact that the rotating member and the rotating body engage with each other at multiple locations means that the load due to their engagement is distributed over multiple equally spaced locations, reducing the load on each transmission piece and reducing the transmission By increasing the thickness of the transmission piece in the axial direction, the strength of the transmission piece is increased.Therefore, even if the individual transmission pieces are made thinner, the problem of breakage of the transmission piece is reduced, the overall diameter is small and thin, and the ratchet slip torque is reduced. can be made smaller. Furthermore, since the transmission piece can be made thinner and the load can be distributed, it is possible to set fine steps. Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments. In the embodiment described below, the present invention is applied to a full winding mechanism for a music box. In FIGS. 1 to 3, reference numeral 1 indicates a first gear as a rotating member made of synthetic resin, and reference numeral 2 indicates a winding shaft called the truest winding shaft as a rotating body. A toothed portion 3 is formed on the outer peripheral edge of the gear 1, into which a second gear of a drum body (not shown) engages. A shaft hole 6 is formed in the center of the gear 1 and has a shaft hole 5 that rotatably fits and supports the shaft 4 of the winding shaft 2. It is connected to the outer periphery. The end surface of the shaft hole 6 is recessed one step further than the end surface of the gear 1, and a wavy fin portion 8 of the winding shaft 2, which will be described later, is fitted into the recess 6a. Approximately at the center in the longitudinal direction of each of the radial rods 7,
Transmission pieces 9 are each formed in a clockwise direction. The transmission piece 9 is made up of a curved part 11 extending along the peripheral wall 10, a folded part 12, and an engaging part 13 formed at the tip of the folded part. In the uncontacted state (see FIG. 1), the free end of the transmission piece 9 is in a position where it does not come into contact with either the peripheral wall 10 or the radial beam 7. Further, the transmission piece 9 has elasticity to return to the above state due to the rotation member being formed of synthetic resin, and the engagement portion 13 has elasticity to return to the above state.
is located on the rotation locus of the protrusion of the wavy fin portion 8, which will be described later. The winding shaft 2 is composed of a shaft 4, a locking piece 14 that locks one end of the entire length (not shown), a wavy fin portion 8 having a protrusion 15, and a threaded portion 16 into which a winding key is screwed. . The illustrated winding shaft 2 is made of metal, and
Six projections 15 are provided. The shaft portion 4 of the winding shaft 2 is fitted into the shaft hole 5 of the gear 1, as shown in FIGS. 2 and 3. At this time, the wavy fin part 8 is fitted into the recessed part 6a, as shown in FIG. Further, among the six protrusions 15, protrusions 15a and 15d located at symmetrical positions with respect to the axis center correspond to the transmission pieces 15a and 15d located at symmetrical positions among the four transmission pieces 9.
They are engaged with engaging portions 13a and 13c of a and 9c, respectively. It is assumed that the winding shaft 2 is given a clockwise rotational habit (in FIG. 2) by a full movement (not shown). On the other hand, the transmission piece 9 and the engagement part 13 other than those described above are
are separated from each other. Now, the operation of the present invention configured as described above will be explained separately for two modes: full winding mode and gear drive mode. Full Winding Mode In FIG. 4, when the winding shaft 2 is rotated counterclockwise, that is, in the direction of winding up the full length (not shown), the protrusion 15 hits the side end 12a of the folded portion 12 of the transmission piece 9. This causes the transmission piece 9 to deflect outwardly against its elastic behavior. At this time, the transmission piece 9 presses the outer part 11a of the curved part 11 against the peripheral wall 10, and then further pushes the outer part 11a of the curved part 11 against the peripheral wall 10.
2 is deflected radially outward. and,
When the projection 15 is further rotated from the position shown in FIG. 4 and reaches the position shown in FIG. 2, the sliding contact between the side end 12a of the curved portion 12 and the projection 15 is released. As a result, the transmission piece 9 returns to its unloaded state due to its own elasticity, positions the engaging portion 13 within the rotation locus of the protrusion 15, and at the same time prevents the creep deformation of the curved portion 11 by the protrusion 15. prevent. At this time, when the winding onto the winding shaft 2 is stopped, as shown in FIG.
Since a relatively strong rotational force in the clockwise direction is exerted by the full movement (not shown), the protrusion abuts against the engaging portion 13. The transmission piece 9 pressed by the protrusion 15a is bent in the counter-time direction around its base end, and
The outer portion 11a of the curved portion 11 is brought into contact with the peripheral wall 10. Such engagement between the protrusion 15a and the engaging portion 13 and the accompanying deflection of the transmission piece 9 are caused by the protrusion 1 provided at a symmetrical position
A similar problem occurs between 5d and the engaging portion 13c.
That is, the rotational force due to the full movement acting on the winding shaft 2 prevents its behavior at the symmetrical position. Gear Drive Mode When the music box is playing, when the braking action on the gear train connected to the gear 1 is released, the entire torque applied to the winding shaft 2 is applied to the protrusion 15a and the engaging portion that are engaged with each other. 13a and protrusion 1
5d and the engaging portion 13c. At this time, the outer part 11a of the curved part 11 of the transmission piece 9 is brought into contact with the peripheral wall 10 due to its flexibility, so that the transmission piece 9 is given rigidity integral with the radial rod 7, and the gear 1 Rotate. In the case of the illustrated embodiment, there are four transmission pieces 9 (four equally spaced at 90 degrees) and six protrusions 15 (six equally spaced at 60 degrees), so as shown in the schematic diagram in FIG. , two symmetrical positions are engaged to transmit torque, and when the winding is fully hoisted, ratchets are activated every 30 degrees (12 divisions). Figure 5a shows a state in which the protrusions 15a and 15d are engaged with the transmission pieces 9a and 9c, respectively. In this state, when the winding shaft 2 is rotated counterclockwise, it is rotated by 30 degrees. At this time, as shown in FIG. 5B, the protrusions 15b and 15e engage with the transmission pieces 9b and 9d, respectively, thereby acting as a check.
That is, there is a relationship between the projections 15 and the transmission pieces 9, such that one is a non-integral multiple of the other and has a common divisor (“2” in the illustrated example). It is set. The common divisor "2" is the number of engagement points between the protrusion and the transmission piece. Therefore, by changing the respective set numbers of transmission pieces and protrusions, it is possible to select the engagement location and the operating angle of the ratchet during torque transmission. The following table shows the relationship between the number of transmission pieces and projections, their mutual engagement points during torque transmission (which is a common divisor of the number of transmission pieces and projections), and the operating angle of the ratchet.

[Table] The values in the table above are representative examples. Generally, the greatest common divisor of the dividing angles of the transmission piece and the protrusion is the ratchet operating angle, and the least common multiple is the angle of the torque transmission location (see the remarks column in the table above). Next, referring to FIG. 6, different examples of transmission pieces provided on the gear will be explained. The transmission piece 90 has a curved portion 9 extending from the radial beam 70 along the peripheral wall 100.
0a, and a partial cylindrical inner peripheral wall 100 following the peripheral wall 100
a folded portion 90b extending along the circumferential wall 100a, and a folded portion 9 extending along the circumferential wall 100b following the circumferential wall 100a.
It consists of 0c. The tip of the folded portion 90c is an engaging portion 90d with which the protrusion 15 abuts,
Unlike the engaging portion 13, a stepped portion is not formed. Furthermore, the example shown in FIG. 6 is characterized in that each portion of the transmission piece 90 is positioned along each peripheral wall. Furthermore,
In this example, the winding direction of the winding shaft (not shown) is opposite to that of the example shown in FIG. 2.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention;
Figure 2 is a plan view of the same as above, Figure 3 is - in Figure 2.
4 is a partial plan view showing the action of FIG. 2, FIG. 5 is a schematic diagram showing the mode of engagement between the transmission piece and the protrusion, and FIG. 6 shows a different example of the transmission piece. FIG. 3 is a partial plan view of the rotating member. 1... Gear (rotating member), 2... Winding shaft (rotating body), 9... Transmission piece, 13... Engaging portion, 15...
protrusion.

Claims (1)

[Scope of Claims] 1. In a ratchet mechanism that includes a rotating member made of synthetic resin and a rotating body that is provided coaxially with the rotating member and a part of which engages with the rotating member, the center of the rotating member forming a shaft hole portion having a shaft hole in the shaft hole portion, the shaft hole portion being connected to the outer peripheral portion by equally spaced radial rods, forming a stepped portion in the shaft hole portion and a part of the radial rods outside the radial rod; A transmission piece having an engaging part with a free end on the inside and integral with the rod on the outside is provided in the space penetrating vertically on the side, and the shaft of the rotating body fitted in the shaft hole has the above-mentioned transmission piece. It has a plurality of protrusions that engage with the engaging part at equal intervals, and is integrally provided with a wavy fin part that fits into the stepped part, and the number of each of the transmission piece and the protrusion is a non-integer multiple of the other. and a ratchet mechanism set to have a common divisor.