JPS58211052A - Power transmission device - Google Patents

Abstract

PURPOSE:To reduce the frictional loss of a worm gear and improve its transmission efficiency, by adopting balls which can freely rotate as a tooth of a worm wheel. CONSTITUTION:A worm gear is constituted by meshing a worm 12 with a worm wheel 15. Teeth of the worm wheel 15 are constituted such that a ball 18 is supported through balls 30 of small diameter in a recess 20 and this ball 18 is held by a holding member 21.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power transmission device, and more particularly to a worm gear device.

Worm gear devices are generally widely used in which the angle between the two axes is a right angle, a helical winding groove is provided on a single-force gear called a worm, and the rotation of the worm is used to transmit power to the other gear. However, this type of power transmission [f] has the disadvantage that the frictional loss of power is large because the burr that occurs along the length of the gear teeth is very large.

In addition, Hindley's drum-shaped drum device, or drum-shaped drum device, consists of a drum-shaped drum having a helical groove and a worm gear. Due to the large number of meshing teeth, the area that supports the pressure between the teeth is larger than that of a normal worm gear, which reduces gear wear and creates a large negative capacity with a relatively small driving force. It has the advantage of being able to convey information.

However, in this type of gear mechanism, there is a problem in that even if the worm moves slightly in a direction perpendicular to its longitudinal axis, the engagement immediately becomes poor.

Patent Application No. 3 was published in 1982 as a power transmission device that eliminates various drawbacks of the conventional Hindley arm system.
The 2,326 design consists of a so-called hint-arm 4-me, which is formed by providing a spiral groove on the periphery of a drum-shaped member, a disk device having a groove at a predetermined angle on the periphery, and a disk device that engages with the 4-me. A power transmission device is disclosed which includes a single-digit ball bearing device extending radially as shown in FIG.

Although the device of the invention of the said patent application operates very effectively, the 4M construction of the device is somewhat complex and it is difficult to reduce the overall size of the device too much.

Here, the present invention is a power transmission device that can be applied to both conventional 4-m gear devices and Hindley worm devices, and eliminates various problems of these 4-m gear devices. The purpose of this invention is to provide a device with a simple structure and high efficiency.

A further object of the present invention is to provide a power transmission device of the above type that is particularly compact and suitable for medium to low speed rotation.

BRIEF DESCRIPTION OF THE DRAWINGS In order that these and many other features and advantages of the invention may be readily understood, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the power transmission device of the present invention. The power transmission device 10 of the invention includes a frame 12 fixed to a drive shaft 11, and a frame 12 spaced apart from the drive shaft 11. and a disc device 14 attached to a driven shaft 13 perpendicular to the drive shaft 13.

In order to transmit the rotation of the drive shaft 11 to the driven shaft 13,
In order to rotate the disc device 14 by meshing with the helical groove 16 of the worm 12, the periphery of the disc 15 of the disc device 14 is provided at a predetermined interval along its entire circumference. The pitch of the groove 16 is such that the ball 18 can rotate freely.

In order to rotatably attach the balls 18 to the periphery of the disc 15, for example, as shown in FIG.
A hemispherical recess 20 is provided. A portion of the ball 18 housed in the hemispherical recess 20 protrudes outward and engages with the groove 16 of the worm 12, and the holding member 2 is used to prevent the ball 18 from escaping from the recess 20. Support Jru1,
The holding member 21 has an opening with a diameter smaller than the diameter of the ball 18.
As a plate or band 5-shaped member having 22, 1lc-
After the housing 18 is housed, it is attached to the corresponding part of the periphery of the disc 15 using suitable fixing means such as screws.

In order to accommodate the ball 18 in the recess 20 of the disk 15, instead of doing the above, for example, the disk device 14 can be fixed by overlapping two U as shown in FIG. &43. It is composed of two discs 15A and 15B, and a ball 18 is placed at a predetermined position on the periphery of the side surface of each disc.
A hemispherical recess 2 that partially protrudes from the periphery and accommodates the external force.
OA, 20B can also be formed.

FIG. 4 shows another embodiment of the disc device in the power transmission device of the present invention. As shown in this figure, the frame 1
A recess 20 on the periphery of the disc 15 so as to engage with the groove 16 of the disc 15.
In order to make the rotation of the ball 18 arranged in the ball 18 more smooth, a plurality of balls 30 having a smaller diameter than the ball 18 can be accommodated in the recess 20 on the bearing surface of the ball 18 .

In the present invention, a spherical bearing may be used instead of the balls 18 disposed around the circumference of the disc 15.

When this invention is particularly applied to a drum-shaped arm, the lead angle of the groove of the arm changes, making it impossible to smoothly transmit power without problems such as bumps.

Preferred embodiments of the present invention have been described below, but the power transmission device of the present invention can be implemented with numerous modifications within the scope of the claims.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway schematic elevational view of an embodiment of the power transmission device of the present invention, and Fig. 2 is a partially cutaway schematic elevational view of a power transmission device according to the present invention.
15, FIG. 3 is a partial sectional view showing another embodiment of the disc device, and FIG. 4 is a partial sectional view showing another embodiment of the disc device. In the drawings, the relationship between reference numerals and constituent elements is as follows. 10... Power transmission H position 11... Drive shaft 12... Worm 13... Driven wheel 14... Disc device 15. 15A, 15B... Disc 16... Spiral shaped Groove 18...Ball 20.20△, 20B...Recess 30...Small diameter ball

Claims (1)

[Scope of Claims] 1. A worm, a disk that can rotate about an axis perpendicular to the longitudinal axis of the four-arm, and a disk that includes a worm on the periphery of the disk. A power transmission device comprising balls arranged at intervals with a pitch and capable of meshing with the shaft, which are mounted so as to be freely rotatable. 2. The power transmission device according to claim 1, wherein the worm is a drum-shaped worm. 3. A recess is provided on the periphery of the disc in which holes can be placed at intervals corresponding to the pitch of the worm.
, by causing the ball to protrude from the periphery of the disk,
- The power transmission device according to claim 1 or claim 2, wherein the hole is capable of engaging with a groove in the recess, and further allows the hole to rotate freely within the recess. 4. According to claim 1 or 2, a plurality of balls having a smaller diameter than the balls are disposed between the balls that can engage with the grooves of the worm and the recesses of the disc. The power transmission device according to any one of the above. 5 Claim 1 in which the ball is a spherical bearing
The power transmission device according to any one of Items 1 and 2.