JPH0821501A - Friction dececlerator - Google Patents

Abstract

PURPOSE:To provide a friction vehicle hypocycloid mechanism whose vibration and noise are reduced, by providing a mutual surface contact engagement portion that is by means of mountain projecting surfaces and valley recessed surfaces, and a tightening means to give the compression force of a direction that contracts slit groove widths. CONSTITUTION:A mutual surface contact engagement portion is equipped by means of mountain projecting surfaces and valley recessed surfaces by providing recessed and projecting surfaces consisting of mountains 18a, 23a and valleys 18b, 23b in a section crossing with the displacement direction of relative displacement action on a friction inner periphery surface (a first friction surface) 14 and a friction outer periphery surface (a second friction surface) 22. Also, slit grooves 19, 25 are provided at the places of valleys 18b, 23b formed at each of the firs and second friction surfaces 14, 22, and a tightening means 26 that gives regulatable compression force in a slit groove width direction and regulates the frictional force of the mutual surface contact engagement portion is equipped. As a result, through an ample contact area, friction transmission becomes possible, and in addition vibration and noise that are generated in the case of a hypocycloid mechanism using a gear mechanism can be reduced sufficiently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction reduction device,
In particular, the hypocycloid mechanism has a fixed element having a large friction inner peripheral surface, and a friction outer peripheral surface that frictionally engages a revolution raceway surface formed along the friction inner peripheral surface of the fixed element,
The present invention relates to a friction reduction device having a structure including a planet element that generates deceleration output due to rotation displacement while performing planetary movement displacement.

[0002]

2. Description of the Related Art A planetary gear having a ring-shaped inner toothed wheel and an outer toothed wheel that meshes with the inner toothed wheel to perform planetary movement by eccentric movement while also rotating about its own axis. The mechanism is known as a hypocycloid mechanism, and when the difference in the number of teeth between the inner toothed wheel and the outer toothed wheel that performs planetary movement is small, especially when the tooth number difference is "1", It is known that a large deceleration output can be taken out as the rotation output of the outer toothed wheel with respect to the planetary motion input given to the toothed wheel. It is also widely known that this hypocycloid mechanism is a mechanism that theoretically achieves high transmission efficiency, and is therefore widely used as a speed reducer in industrial equipment such as industrial robots.

[0003]

As described above, the hypocycloid speed reducer is configured with the gear mechanism as a structural element. According to the gear mechanism, the teeth of the internal tooth gear are changed to the teeth of the external tooth gear. There is a problem in that it is not possible to avoid generation of vibrations and noises due to repeated engagement starting and disengagement from the engaged state.

Further, when a hypocycloid mechanism having a small difference in the number of teeth is formed by a general gear, interference called trochoidal interference is likely to occur. When trochoidal interference occurs, it becomes impossible to assemble the gear mechanism. On the other hand, in order to avoid the above trochoidal interference, a pin gear mechanism may be used. In the case of the same mechanism,
Machining is more difficult than involute tooth profiles, and there are problems in terms of gear accuracy and manufacturing costs.

Further, a friction wheel mechanism may be used instead of the gear mechanism. That is, a hypocycloid mechanism is constituted by an internal friction wheel and an external friction wheel,
It is necessary to adjust the frictional force from the transmission mechanism, and the frictional force of a pair of external friction wheels can be adjusted by adjusting the center distance between the two vehicles. Since it is difficult to construct a mechanism that easily adjusts the center distance between the external friction wheel and the external friction wheel, there is a problem of poor practicality.

Therefore, an object of the present invention is basically a hypocycloidal mechanism having an internal friction wheel and an external friction wheel as basic structural elements, and at the same time, a friction force required for contact transmission between the both vehicles. It is an object of the present invention to provide a friction reduction device with a built-in structure capable of setting the level to a level sufficiently higher than the surface contact by the friction peripheral surface. Another object of the present invention is to provide a friction speed reducer equipped with a frictional force adjusting means capable of easily adjusting a frictional force on a frictional contact surface of a friction wheel.

[0007]

SUMMARY OF THE INVENTION The present invention comprises two fixed,
Expansion of the contact area of the friction engagement part by the friction surface formed on the movable member is achieved by the surface contact of the uneven friction surfaces composed of the convex convex surface and the concave concave surface, and the simple inner and outer friction surfaces. The friction reduction device is configured so that the transmission efficiency can be improved more than the surface contact between the circumferential surfaces due to.

Further, a slit groove is further provided in a valley portion between the convex surfaces, and a tightening means for externally applying a compressive force in a direction of reducing the slit groove width is provided. The configuration is such that the pressure contact force is increased at the meshing portion of the concave and convex contact surfaces of the two fixed and movable members so that the frictional force acting between the two surfaces can be adjusted. That is,
According to the present invention, a relative displacement operation at a predetermined speed is provided by surface contact between a first member having a first friction surface and a second member having a second friction surface. In a friction reduction device that obtains a decelerated displacement operation from one of the two members, a peak and a valley in a cross section intersecting the displacement direction of the relative displacement operation on the first friction surface and the second friction surface. And a concave-convex surface, and an inter-surface contact engagement portion formed by the mountain-shaped convex surface and the valley-shaped concave surface, and a slit groove is formed in the valley portion formed in each of the first and second friction surfaces. Another object of the present invention is to provide a friction reduction device including a tightening unit that applies an adjustable compressive force in the slit groove width direction to adjust the frictional force of the mutual surface contact engagement portion.

According to the present invention, further, the first member having the first friction surface is a fixed annular member having a friction surface in which a mountain-shaped convex surface and a valley-shaped concave surface are connected to the inner peripheral surface of the cylinder. The second member having the second friction surface is a movable disk member having a friction surface in which a mountain-shaped convex surface and a valley-shaped concave surface are continuously provided on a cylindrical outer peripheral surface, and the movable circular member Displacement input means for applying a planetary displacement input to the plate member with the cylindrical inner peripheral surface of the fixed annular member as a revolution orbit, and rotation displacement output generated with planetary displacement of the movable disc member as deceleration output. Provided is a friction speed reducer in which a hypocycloid speed reduction mechanism is formed by providing output means for taking out.

[0010]

According to the above-mentioned structure, the friction engagement surfaces of the first and second members respectively have the uneven surface composed of the ridges and the valleys, and the mountain-shaped convex surface and the valley-shaped concave surface make the mutual surface contact engagement. Since the joint portion is configured, friction transmission is possible through a rich contact area, the transmission efficiency can be improved, and the friction force in the mutual surface contact engagement portion can be increased by the tightening means for adjusting the friction force. Therefore, it is possible to obtain a friction reduction device having optimum transmission efficiency and capable of sufficiently reducing vibration and noise generated in the case of a hypocycloid mechanism using a gear mechanism. It will be possible.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail based on the embodiments shown in the accompanying drawings. FIG. 1 is a schematic longitudinal sectional view showing the structure of a friction reduction device according to the present invention, and FIG.
2 is a side view illustrating the contact state between the fixed annular member and the movable disc member as viewed from the arrow 2 line, and FIG. 3 is a partial cross-sectional view showing the meshing state of the uneven friction surface viewed from the line 3-3 in FIG. 4 and 5 are sectional views similar to FIG. 3 and showing another embodiment.

First, referring to FIG. 1, a friction reduction device 1
Reference numeral 0 denotes a casing 12 that forms a casing of the device 10, and is extended annularly inside the casing 12 and has an inner peripheral surface as an inner peripheral surface for frictional contact (hereinafter, referred to as friction inner peripheral surface 14). The provided first annular member 16 is integrally formed. This first
The second disc member 20 (hereinafter, referred to as a second disc member 20) in which the movable disc member performing the orbital movement cooperates with the first annular member 16 by eccentrically moving while making rolling contact with the friction inner peripheral surface 14 of the annular member 16. It is provided as a second movable disk member), and therefore the movable disk member 20 has an outer peripheral surface as an outer peripheral surface for frictional contact (hereinafter referred to as a friction outer peripheral surface 22).
Further, a flange portion 24 having a rotary bearing (not shown) built therein is provided on one end side of the central portion of the second movable disc member 20.

The flange 24 of the second movable disk member 20 has a drive motor 40 (the casing 12) as a drive source.
The crankshaft 44 directly connected to the output shaft 42 of the second movable disc member 20 rotates when the crankshaft 44 is rotated by being driven by the drive motor 40. The friction surface 22 is connected to the first annular member 1
While frictionally engaging the friction inner peripheral surface 14 of No. 6, it operates as a planet element that revolves. That is, the second movable disk member 20 having the friction outer peripheral surface 22 makes a revolving motion with respect to the first annular member 16 having the friction inner peripheral surface 14 to form a hypocycloid mechanism.

At this time, the second movable disc member 20 performs a rotation operation in the process of performing a planetary motion by friction surface contact with the first annular member 16, and this rotation motion of the drive motor 40. The rotation input applied from the crankshaft 44 directly connected to the output shaft 42 is decelerated to form the rotation output.
Then, the output generated in the second movable disc member 20 is, for example, an appropriate joint means 3 such as a well-known Oldham joint.
It is transmitted to the output element 34 rotatably supported by the rotary bearing 32 of the casing 12 via 0, and is taken out from the output element 34 as a decelerated rotation output.

The rotation output of the output element 34 is a non-contact type rotation detecting means 35 comprising an electric detector such as a photoelectric detector or a proximity switch arranged between the casing 12 and the output element 34. Is detected and the detected force is sent to the outside through the signal line 36. By feeding back the detection output, the first inner force of the first annular member 16 relative to the friction inner peripheral surface 14 is detected. It can be used as a correction signal for correcting the slippage of the friction outer peripheral surface 22 of the second movable disk member 20.

In FIG. 1, reference numeral 26 indicates a friction force adjusting means which will be described later, and a friction surface between the friction inner peripheral surface 14 of the first annular member 16 and the friction outer peripheral surface 22 of the second movable disc member 20. In order to be able to set the frictional force in the contact engagement to an appropriate level, for example, a plurality of them are arranged at substantially equal intervals along the peripheral region of the second movable disc member 20. here,
Referring to FIG. 2, the friction inner peripheral surface 14 is formed on the first annular member 1.
6 and a second movable disk member 20 having a friction outer peripheral surface 22 that performs eccentric movement with the friction inner peripheral surface 14 as an orbit orbit are shown and extracted.

The first annular member 16 is formed as an annular element having a diameter Da centered on the fixed center P1, while the second movable disc member 20 has a center P2 and a diameter Db (<D
It is formed as a disc element according to a). The center P2 of the second movable disk member 20 has an eccentricity "e" with respect to the center P1 of the first annular member 16. Therefore, when the outer peripheral surface 22 of the second movable disc member 20 is given a revolving motion due to the frictional surface contact with the inner peripheral surface 14 of the first annular member 16, the second movable disc member 20 becomes , Rotate around the center P2 based on the friction surface contact. That is, as described above, the revolution motion input is decelerated and converted into the rotation motion output.

In practice, the friction outer peripheral surface 2 of the second movable disc member 20 is opposed to the friction inner peripheral surface 14 of the first annular member 16.
No. 2 has a small difference in diameter (Da-Db), that is, a difference in curvature, and therefore causes a slight elastic deformation during eccentric movement of the second movable disc member 20, and therefore the first annular member 16 is formed.
When the frictional inner peripheral surface 14 is brought into surface contact, its surface contact area in the direction of the revolution orbit is considerably wide, and a large frictional force is obtained to perform a deceleration action without slip.

It is well known that the rotation motion output of the second movable disk member 20 has a deceleration rate i expressed by the following equations (1) and (2) with respect to the revolution motion input. i = (Da−Db) / Db ... (1) = 2e / Db ... (2) However, the present invention has a structure for further expanding the above-mentioned surface contact area in the above deceleration action. There is.

That is, as clearly shown in FIG. 3, the friction inner peripheral surface 14 of the first annular member 16 is provided with irregularities composed of a plurality of ridges 18a and valleys 18b running in the circumferential direction in the axial direction of the apparatus (first Is continuously provided in the axial direction of the annular member 16), and the second
On the outer peripheral surface 22 of friction of the movable disk member 20, irregularities composed of a plurality of peaks 23a and valleys 23b running in the circumferential direction are continuously provided in the axial direction of the disk member 20. And both members 1
Since the irregularities 6 and 20 are arranged so as to mesh with each other as shown in the figure, the friction surface contact engagement region is further expanded to have a structure having a rich contact area. Of course, it goes without saying that the surfaces of the peaks 18a, 23a and the valleys 18b, 23b are formed to be relatively rough so as to have an appropriate friction coefficient.

In this way, the second movable disc member 20 has the friction inner peripheral surface 14 of the first annular member 16 based on a large friction force.
To orbit the orbital plane to perform a planetary motion to perform deceleration. Moreover, according to the present invention, the peaks 18a and 23 of the friction inner peripheral surface 14 and the friction outer peripheral surface 22 described above are further provided.
On the uneven friction surface composed of a and the valleys 18b and 23b,
Slit grooves 18 and 25 are formed at the bottoms of the valleys 18b and 23b. In addition, both the first and second members 16 and 20
A bolt screw 23a and a nut 23b capable of applying a compressive force in the axial direction to the surface contact area of the concave and convex meshing portion are provided. The bolt screw 23a is inserted so as to penetrate the second movable disc member 20, has a bolt head at one end, and has the other end screw-engaged with the nut 23b. If the bolt screw 23a and the nut 23b are provided in this manner, the first and second members 16 and 2 are tightened according to the tightening of the two.
The slit grooves 19 and 25 in the concave and convex meshing portion 0
Since the compressive force acts in the groove width direction of, it is possible to increase the surface contact pressure, and thus the frictional force, in the frictional contact surface regions of the peaks and valleys, and conversely, by gradually reducing the tightening force,
It is possible to reduce the frictional force.

That is, the bolt screw 23a and the nut 23
The friction force adjusting means 26 is constituted by b. Then, such bolt screw 23a and nut 23
Preferably, b is, as clearly shown in FIG. 2, when a plurality of circumferentially equidistantly arranged circumferential edges of the second movable member 20 are provided, frictional surface contact is substantially uniform at each circumferential portion. It is possible to adjust the engagement.

Here, referring again to FIG. 1, a state in which the frictional force adjusting means 26 is arranged inside the speed reducer 10 in the peripheral region of the second movable disk member 20 is illustrated. Has been done. The friction reduction device 10 has a built-in reduction device by connecting the drive motor 40 to one end of the friction reduction device 10, and constitutes a kind of unitized rotary drive device that extracts the deceleration output from the output member 34. is there.

FIG. 4 is a partial sectional view similar to FIG. 3, showing the structure of the second movable disk member 20 and another embodiment of the frictional force adjusting means 26. As shown in FIG. 4, the second movable disc member 20 has a configuration in which a plurality of disc elements 122 are overlapped with each other in the axial direction of the same disc member 20, and both sides of the disc element 122 are arranged. Alternatively, a slit groove 125 having a mountain portion 123a in the outer peripheral area of one surface and a circular hole 126 at the groove bottom is provided.
In order to obtain

With this structure, the processing of each disc element 122 of the second movable disc 20 is facilitated, and at the same time, the first annular member 16 and the second movable disc member 20 are processed. When a frictional force is adjusted by applying a compressive force in the axial direction in the concavo-convex meshing region, the slit groove 125 has the circular hole 126, so that the compressive displacement of each crest 123a can be facilitated. This has the advantage that the action is further simplified.

The friction force adjusting means 26 is a bolt screw 2
The disk element 1 at the end portion is replaced with the threaded portion 26c formed at the tip of 6a in place of the above-described structure for screw-engaging with the nut 26b.
A simple structure may be employed in which a screw hole 26d formed in 22 is screw-engaged. Of course, also in this case, a plurality of bolt screws 26a and screw holes 26d are formed in the peripheral area of the second movable disk member 20 at equal intervals in the circumferential direction, as shown in FIG. It is preferable to arrange the frictional force adjusting means 26 consisting of

[0027]

As is clear from the description of the above embodiments, according to the present invention, unlike the hypocycloid mechanism constituted by the gear mechanism, the friction wheel that performs rotational transmission by surface contact is a basic element. In configuring the friction reducer with the hypocycloid mechanism, the contact area in the frictional surface contact engagement between the inner peripheral surface and the outer peripheral surface is configured by the contact of the uneven surface, so that the surface contact area is significantly increased. Has been expanded,
Therefore, it is possible to reduce the slippage as much as possible to improve the transmission efficiency, and, unlike the gear mechanism, it is possible to significantly reduce the vibration level and the noise level.

Moreover, at the frictional surface contact engagement portion,
Since the frictional force can be adjusted so as to enable transmission with proper efficiency by providing the frictional force adjusting means, for example, the friction reduction device according to the present invention can be used as a joint drive source for an industrial robot. When used as, it becomes possible to use it as a compact and highly accurate rotary drive device.
Furthermore, the friction inner peripheral surface and the outer peripheral surface having the uneven surface formed by the peaks and valleys according to the present invention are easier to cut than the gears, and therefore are advantageous in terms of the ease of processing, and therefore the device The manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing the configuration of a friction reduction device according to the present invention.

FIG. 2 is a side view illustrating a contact state between a fixed annular member and a movable disc member as viewed from the line 2-2 of FIG.

FIG. 3 is a partial cross-sectional view showing a meshing state of the concave-convex friction surface as seen from a line 3-3 in FIG.

FIG. 4 is a sectional view similar to FIG. 3, showing another embodiment.

[Explanation of symbols]

 10 ... Friction reducer 12 ... Casing 14 ... Friction inner peripheral surface 16 ... First annular member 18a ... Mountain 18b ... Valley 19 ... Slit groove 20 ... Second movable disc member 22 ... Friction outer peripheral surface 23a ... Mountain 23B ... Valley 24 ... Crankshaft 25 ... Slit groove 26 ... Friction force adjusting means 34 ... Output member 40 ... Drive motor

Claims (2)

[Claims] 1. A first member having a first friction surface and a second member.
And a second member having a friction surface of the second member, a relative displacement operation at a predetermined speed is provided by surface contact, and a reduced speed displacement operation is obtained from one of the first and second members. A concave-convex surface composed of peaks and valleys is provided on the first friction surface and the second friction surface in a cross section intersecting with the displacement direction of the relative displacement operation, and mutual contact is made by the convex convex surface and the concave concave surface. An engaging portion is provided, slit grooves are provided at the valley portions formed in each of the first and second friction surfaces, and an adjustable compressive force is applied in the slit groove width direction to provide the mutual surface contact. A friction reduction device comprising a tightening means for adjusting a frictional force of an engaging portion. 2. The first member having the first friction surface is a fixed annular member having a friction surface in which a mountain-shaped convex surface and a valley-shaped concave surface are continuously provided on the inner peripheral surface of the cylinder, and the first member is provided. The second member having two friction surfaces is composed of a movable disc member having a friction surface in which a mountain-shaped convex surface and a valley-shaped concave surface are continuously provided on the outer peripheral surface of the cylinder, Displacement input means for giving a planetary displacement input with the inner circumferential surface of the cylinder of the fixed annular member as an orbit, and output means for extracting as a deceleration output the rotational displacement output generated with the planetary displacement of the movable disk member, The friction reduction device according to claim 1, wherein a hypocycloid reduction mechanism is formed.