JPS60168954A - Reduction gear - Google Patents

Abstract

PURPOSE:To obtain the superior power transmission capacity and a large reduction ratio with a small-sized reduction gear by arranging two discs in the opposed state through two rolling bodies retained by the respective retainers and fixing one retainer and revolving the other. CONSTITUTION:The grooves 5-8 in sine-curve form are formed onto each plane 3, 4 of two discs 1 and 2. The both discs 1 and 2 are opposed through the rolling bodies 9 and 10, which are retained by two retainers 11 and 12. The both discs 1 and 2 are rotatably supported, and one retainer 11 is fixed, and the other retainer 12 can be revolved. When one disc 1 is revolved as input side, the other disc 2 is revolved in the opposite direction to the disc 1. The rotatable retainer 12 revolves in the same direction to one disc 1, and the number of revolution is decelerated and output. Therefore, the power transmission capacity having a high efficiency and a large reduction ratio can be obtained with a small-sized reduction gear.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field to which the Invention Pertains] The present invention relates to a reduction gear, and particularly to a reduction gear that can obtain a large reduction ratio while reducing the overall size.

[Prior art and its problems]

For example, many devices that use a motor as a power source transmit the rotation of the motor to a load via a speed reducer (-7).

Incidentally, various reduction gears for such uses have been proposed in the past, but the most commonly used one is a combination of small gears and large gears. In other words, the small gear is rotated by the input rotating shaft, and the large gear meshed with the small gear (!
l! This is a gear type reducer that transmits one revolution to the output rotating shaft.

However, gear type reducers have the following problems. Here, the number of teeth on the small gear is 21, and the number of teeth on the large gear Z2+
If the pitch circle diameter of the small gear is DI and the pitch circle diameter of the large gear is D2, then the reduction ratio ``U'' is as follows. Therefore, in order to increase the reduction ratio U, the pitch circle diameter D1 of the small gear is made small. Alternatively, it is necessary to increase the pitch circle diameter D2 of the large gear.However, since there is a limit to the minimum number of gear teeth, in order to set the reduction ratio U sharply, the pitch circle diameter of the large gear must be increased. As a result, the entire reducer inevitably becomes larger.In addition, in the case of a gear type reducer, one of the teeth of the small gear and large gear that are in contact with each other is
-The power is transmitted through two teeth. Therefore, in order to transmit the necessary power, it is necessary to set the individual teeth to a size that can withstand the transmission of that force. Therefore, from this point of view as well, if one attempts to set the reduction ratio U too sharply, there is a problem in that the overall size inevitably increases.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to provide a reduction gear that is compact, provides efficient power transmission characteristics, and provides a large reduction ratio. It is in.

[Summary of the invention]

Two discs oppose each other via rolling elements, and the opposing surfaces of the two discs are provided with two meandering grooves that intersect the reference circle at a constant pitch. The diameter of the reference circle of one of these two grooves is larger than the reference circle of the other groove. A rolling element is interposed between the two grooves, and the two discs are opposed to each other via the rolling element. There are two retainers to hold the rolling elements in the two grooves.

The two disks are rotatably supported, one of which is on the input side, the retainer is on the output side, and the other retainer is fixed.

Further, since the rotation direction of a disc other than the input side disc is opposite to the rotation direction of the input side disc, this reduction gear belongs to a differential type reduction gear.

〔Effect of the invention〕

In the present invention, since all the rolling elements transmit power, it is possible to achieve small size and high power transmission. Furthermore, by rotating the second disc in the opposite direction, a high reduction ratio can be obtained since it is a differential type.

[Embodiments of the invention]

FIG. 1 shows an embodiment of the present invention.

1st. The planes 3, 4 of the second disc 1.2 are provided with SIN curves '>1445.6, 7.8.

1st. The disks 1.2 of the ixz are opposed to each other via rolling elements 9.10, and there are first and second cages 11.12 for holding the rolling elements 9,10. 1st. Second disk 1, 2
are rotatably supported, the retainer 11 is fixed, and the retainer 12 is rotatably supported.

Here, if the first disk 1 is rotated as the input side, the second
The disk 2 rotates in the opposite direction to the first disk 1. The second retainer 12 rotates in the same direction as the first disk l, and the number of rotations is reduced by 5 and output.

FIG. 2 shows the SIN-curved grooves 5, 6, 7.8 provided in the plane 3.4 of the disk 1.2.

The AA figure shows the cage 11.12, and the long size 13
．． There are 14.

Next, the principle of this embodiment will be explained with reference to FIGS. 4 and 5.

The dotted lines in the figure are the center lines of the SIN curve grooves 5 and 6 provided on the disk 1, and the solid lines are the center lines of the SIN curve grooves 7 and 8 provided on the disk 2. There is a rolling element 9 at the intersection A of the SIN curved groove 5.7, and the SIN
There is a rolling element 8 at the intersection BVcl'i of the N-curved grooves 6 and 8. Here, assuming that the intersections A and B are on the center line P, SIN
Assume that the curved groove 5 is rotated 01 times to the right in the figure. That is, the first disk 1 has rotated 01 times. Therefore, the SIN curved groove 6 has also rotated 01 times. Here, since the rolling element 9 is held at the intersection A by the cage 11, the SIN curve-shaped groove 7 is 0 in the left direction in the figure.
Rotate by 2. That is, the disc 2 rotates in the opposite direction to the disc 1. Therefore, the SIN force ~ the groove 8 is also θ
Turn 1g1 in the opposite direction by 2. FIG. 5 is a diagram when the intersection of the SIN curved grooves 6°8 is set at 05.

The amount of movement at the intersection B is the amount of movement of the holder 12, and is on the output side. Also, the amount of movement of the SIN curved groove 5.6 is
Since it is the input side, the reduction ratio U is given by the following formula.

θl ll θ5 Also, from FIG. 5, the following equation holds true.

θ1+02-03+θ4(2) θ1-03+05(3) The wave number of the SUN curved groove 5, 7.6.8 is z】lZ2
When z3 and z4 are set, the following equation holds true.

Zl・CφSθ1; Z2・CφSθ2 (4) Z3・Cφ
Sθ3=Za'CφSθ4 (5) (1) to (5) above
If we rearrange the equations, the speed reducer U becomes as follows.

Tatami β1. β2 is It is.

For example, if Z+=8+22=9+23=9+Z4=10, the reduction ratio U becomes 171.

In this way, depending on the wave number of each SIN curve groove.

The reduction ratio can be set, and since it is a differential type, a large reduction ratio can be obtained.

Furthermore, since all the rolling elements transmit power, a compact speed reducer is possible.

In this embodiment, the disk is the input and the holder is the output, but any two of the four parts, two disks and two holders, may be used as the input or output.

[Brief explanation of drawings]

FIG. 1 is a line sectional view of an embodiment of the present invention, and FIG. 2 is a diagram showing the principle of the present invention. 1.2...disc, 3,4...flat, 5,6,7.8
・SIN curved groove, 9. IO...Rolling element, 11.1
2...Cage, 13.14...Long size. Figure 4 Figure 5

Claims (1)

[Claims] A first groove having a meandering first groove that intersects a first reference circle on a plane at a constant pitch, and a second meandering groove that intersects a second reference circle on the plane at a constant pitch.
．． The second disc, the first disc, and the m2 disc are the first disc. The first . This speed reducer is characterized in that the first retainer is fixed in opposition to each other via a second rolling element, and the second retainer is rotatably supported.