JP3040490U - Worm gear mechanism - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To reduce frictional resistance between a worm gear and a worm wheel. In a worm gear mechanism including a worm gear 12 that is rotationally driven and a worm wheel 13 that meshes with the worm gear 12, the hardness of the worm gear 12 is set to be higher than the hardness of the worm wheel 13.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention slides a movable body of an optical pickup for a disc player for reproducing, recording or erasing an optical disc or a magneto-optical disc (hereinafter referred to as a disc), which is abbreviated as a CD, for example, along a disc radial direction. The present invention relates to a worm gear mechanism incorporated in a slide feeder mechanism.

[0002]

[Prior art]

 An example of the disc player is shown in FIGS. 2 and 3. This is a supporting frame 1 provided with a turntable 3 rotated by a spindle motor 2 and an optical pickup 4, and the optical pickup 4 is a movable body slidable along a guide rail 5. 6 and a slide feed motor 8 for sliding the movable body 6 along the disc radial directions a and b through the slide feed mechanism 7.

The slide feed mechanism 7 includes a screw rod 10 which is rotatably supported by a support frame 1 via a bearing 9 in parallel with the guide rail 5, and a screw rod 10 which is provided on the movable body 6 and is screwed to the screw rod 10. It is provided with a nut portion 11 to be fitted, a worm gear 12 fitted to the drive shaft 8a of the slide feed motor 8, and a worm wheel 13 fixed to one end of the screw rod 10 and meshed with the worm gear 12.

In the above configuration, for example, when reproducing, after mounting the disk D on the turntable 3, the spindle motor 2 rotates the disk D via the turntable 3 and the slide feed motor. The movable member 6 is slid along the disk radial directions a and b via the slide feeding mechanism 7 by means of 8, and the information recorded on the disk D is read.

Conventionally, as the material of the worm gear 12 and the worm wheel 13, an economical synthetic resin material is used with an emphasis on economy, and the friction resistance between the both 12 and 13 is as shown in FIG. 4 (A- in FIG. 3). As shown in the view (arrow A)), a lubricant 15 such as grease is applied on the tooth surface 12a of the worm gear 12 to reduce the friction.

[0006]

[Problems to be solved by the device]

 In the above-mentioned conventional configuration, the frictional resistance between the worm gear 12 and the worm wheel 13 is only reduced by the lubricant 15 interposed therebetween, so that, for example, the hardness of the worm gear 12 is less than that of the worm wheel 13. When the hardness is smaller than the hardness, microscopically, as shown in FIG. 4, while the tooth portion 13a of the worm wheel 13 bites into the tooth surface 12a of the worm gear 12, the tooth surface 12a is elastically deformed. Since it is moved and its elastic deformation amount t is large, the frictional resistance also becomes large, which becomes an obstacle in improving the trackability of the optical pickup 4 in the radial direction of the disk, and the search operation takes time.

The present invention has been made in view of the above problems, and an object thereof is to provide a worm gear mechanism in which a frictional resistance between a worm gear and a worm wheel is reduced.

[0008]

[Means for Solving the Problems]

 In order to achieve the above object, the invention according to claim 1 is a worm gear mechanism including a worm gear that is rotationally driven and a worm wheel that meshes with the worm gear, wherein the hardness of the worm gear is greater than the hardness of the worm wheel. It is characterized by that.

According to the above configuration, the hardness of the worm gear is set to be greater than the hardness of the worm wheel, and the tooth portion of the worm wheel is moved on the tooth surface of the worm gear while the tooth portion of the worm wheel hardly bites into the tooth surface. Since the amount of elastic deformation is small, it is possible to form a worm gear mechanism that reduces frictional resistance between the worm gear and the worm wheel.

According to a second aspect of the present invention, in the first aspect of the present invention, the worm gear is made of polybutylene terephthalate blended with an inorganic substance, and the worm wheel is made of polyacetal.

According to the above structure, the worm gear is made of polybutylene terephthalate (PBT), which has high mechanical strength and good wear resistance, and is blended with an inorganic substance, and the worm wheel is made of inexpensive polyacetal (POM). Therefore, it is possible to form an inexpensive worm gear mechanism with low frictional resistance.

According to a third aspect of the present invention, in the first aspect of the present invention, the worm gear is made of polybutylene terephthalate blended with an inorganic substance, and the worm wheel is made of polyamide.

According to the above configuration, the worm gear is made of polybutylene terephthalate (PBT), which has high mechanical strength and good wear resistance, and is blended with an inorganic substance, and the worm wheel has a sound deadening polyamide (nylon. Since it is formed of PA), it is possible to form a worm gear mechanism having a low frictional resistance and a sound deadening effect.

A fourth aspect of the invention is the device of the second or third aspect, wherein the inorganic substance is glass fiber.

According to the above configuration, by blending the glass fiber with polybutylene terephthalate (PBT), it is possible to form a worm gear having an even higher hardness.

According to a fifth aspect of the present invention, in the first aspect, the worm gear is made of brass and the worm wheel is made of polyacetal.

According to the above structure, since the worm gear is made of brass having high strength and the worm wheel is made of inexpensive polyacetal (POM), it is possible to form an inexpensive worm gear mechanism having a smaller friction resistance. You can

According to a sixth aspect of the present invention, in the first aspect, the worm gear is made of brass and the worm wheel is made of polyamide.

According to the above structure, the worm gear is made of brass having high strength, and the worm wheel is made of polyamide (nylon / PA) having a sound deadening effect. Therefore, the worm gear having a smaller friction resistance and a sound deadening effect is provided. Mechanisms can be formed.

A seventh aspect of the present invention is the device according to any one of the first to sixth aspects, wherein the worm gear and the worm wheel slide the movable body of the optical pickup for a disc player along the disc radial direction. It is characterized by being incorporated in the feed mechanism.

According to the above configuration, the frictional resistance between the worm gear and the worm wheel of the slide feed mechanism is reduced, the followability of the optical pickup in the radial direction of the disc is improved, and the time required for the search operation is shortened. be able to.

[0022]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a worm gear mechanism of a slide feeding mechanism 7 (see FIGS. 2 and 3) for sliding a movable body 6 of an optical pickup 4 for a disc player showing an embodiment of the present invention. The hardness of 12 is larger than that of the worm wheel 13.

According to the above configuration, the hardness of the worm gear 12 is made larger than the hardness of the worm wheel 13, and the tooth surface 13 a of the worm wheel 13 hardly bites into the tooth surface 12 a of the worm gear 12. 12a and the amount of elastic deformation t thereof is small, it is possible to form a worm gear mechanism with reduced frictional resistance, which improves the followability of the optical pickup 4 in the disk radial directions a and b. The time required for the search operation can be shortened.

As the material for the worm gear 12, a material obtained by blending polybutylene terephthalate (PBT) with an inorganic material (for example, glass fiber) or brass is used, and as the material for the worm wheel 13, polyamide (nylon / PA) or polyacetal (POM) is used. ) Is used.

In the case where the worm gear 12 is made of polybutylene terephthalate (PBT) having a high mechanical strength and good wear resistance and blended with an inorganic substance, and the worm wheel 13 is made of inexpensive polyacetal (POM). In this case, it is possible to form an inexpensive worm gear mechanism that has low frictional resistance.

The worm gear 12 is formed by blending polybutylene terephthalate (PBT), which has high mechanical strength and good wear resistance, with an inorganic substance, and the worm wheel 13 is a polyamide (nylon / PA) having a sound deadening effect. When it is formed by, it is possible to form a worm gear mechanism having a low frictional resistance and a sound deadening effect.

When the inorganic material is formed of glass fiber, it is possible to form the worm gear 12 having an even higher hardness.

When the worm gear 12 is made of brass having high strength and the worm wheel 13 is made of inexpensive polyacetal (POM), it is possible to form an inexpensive worm gear mechanism having a smaller frictional resistance. it can.

In the case where the worm gear 12 is made of brass having high strength and the worm wheel 13 is made of polyamide (nylon / PA) having a sound deadening effect, the worm gear having a smaller friction resistance and a sound deadening effect is obtained. A mechanism can be formed.

[0030]

[Effect of the invention]

 According to the invention of claim 1, the hardness of the worm gear is made larger than the hardness of the worm wheel, and the tooth surface of the worm wheel is set so as not to bite into the tooth surface of the worm gear. Since it is moved and its elastic deformation amount is small, it is possible to form a worm gear mechanism in which the frictional resistance between the worm gear and the worm wheel is reduced.

According to the second aspect of the present invention, the worm gear is made of polybutylene terephthalate having a high mechanical strength and good wear resistance and blended with an inorganic substance, and the worm wheel is made of an inexpensive polyacetal. Since the friction resistance is small, an inexpensive worm gear mechanism can be formed.

According to the third aspect of the invention, the worm gear is made of polybutylene terephthalate having a high mechanical strength and good wear resistance and blended with an inorganic substance, and the worm wheel is made of polyamide having a sound deadening effect. Therefore, it is possible to form a worm gear mechanism that has a low frictional resistance and a sound deadening effect.

According to the invention of claim 4, by blending the glass fiber with the polybutylene terephthalate, it is possible to form a worm gear having a further increased hardness.

According to the invention of claim 5, since the worm gear is made of brass having high strength and the worm wheel is made of inexpensive polyacetal, a worm gear mechanism having a smaller friction resistance and being inexpensive is formed. be able to.

According to the invention of claim 6, since the worm gear is made of brass having high strength and the worm wheel is made of polyamide having a sound deadening effect, the worm gear mechanism having a smaller friction resistance and a sound deadening effect. Can be formed.

According to the invention described in claim 7, the frictional resistance between the worm gear and the worm wheel of the slide feed mechanism is reduced to improve the trackability of the optical pickup in the radial direction of the disk, which is required for the search operation. The time can be shortened.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of a main part of a worm gear mechanism showing an embodiment of the present invention (the cross-section line is taken along the line AA in FIG. 3).

FIG. 2 is a plan view of a disc player incorporating the same worm gear mechanism.

FIG. 3 is an enlarged vertical sectional view of the worm gear mechanism.

FIG. 4 is a longitudinal sectional view showing a conventional example.

[Explanation of symbols]

 4 Optical pickup 6 Movable body 7 Slide feed mechanism 8 Slide feed motor 12 Worm gear 13 Worm wheel

Claims (7)

[Utility model registration claims] 1. A worm gear mechanism comprising a worm gear that is rotationally driven and a worm wheel that meshes with the worm gear, wherein the worm gear has a hardness greater than that of the worm wheel. 2. The worm gear mechanism according to claim 1, wherein the worm gear is made of polybutylene terephthalate blended with an inorganic substance, and the worm wheel is made of polyacetal. 3. The worm gear mechanism according to claim 1, wherein the worm gear is made of polybutylene terephthalate blended with an inorganic substance, and the worm wheel is made of polyamide. 4. The worm gear mechanism according to claim 2, wherein the inorganic material is glass fiber. 5. The worm gear mechanism according to claim 1, wherein the worm gear is made of brass and the worm wheel is made of polyacetal. 6. The worm gear mechanism according to claim 1, wherein the worm gear is made of brass and the worm wheel is made of polyamide. 7. The worm gear and the worm wheel are incorporated in a slide feed mechanism for sliding a movable body of an optical pickup for a disc player along a disc radial direction. Worm gear mechanism described.