JPS6336200Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a planetary roller type power transmission device that transmits power by the frictional force of rollers that are in contact with each other.

An example in which a conventional power transmission device of this type is used as a speed reducer is shown in FIGS. 1 and 2. In both figures, 1 is a sun roller directly connected to an input shaft 8 that is rotationally driven, and 3 is a case 10. Inner rollers 2 fixed to the carrier 6 are a plurality of (three in this case) planetary rollers rotatably supported via bearings 4 on planetary pins 5 fixed to the carrier 6.

11 and 12 are bearings.

The sun roller 1, the plurality of planetary rollers 2, and the inner roller 3 apply a pressing force P to these rollers in the radial direction.
Power is transmitted by the frictional force U generated by the pressure contact.

That is, in this case, the inner diameter Di of the inner roller 3 is the sum of twice the outer diameter Ds of the sun roller 1 and the outer diameter Dp of the planetary roller 2 (that is, Ds+
2Dp) and are assembled, and the above-mentioned pressing force P is generated by elastically deforming these rollers and pressing them against each other. In this case, the following problems arose.

(1) In this type of planetary roller type power transmission device, since the pressure contact force P is always set constant, the frictional force U for transmitting power is also always constant. Therefore, the above-mentioned power transmission device does not have a clutch function for connecting and disconnecting power transmission, and therefore, when an overload is applied, excessive slipping occurs on the respective pressure contact surfaces of the planetary roller 2, the sun roller 1, and the inner roller 3. It is inevitable that a seizing accident will occur and the operation will become impossible.

(2) Also, this kind of planetary roller type power transmission device,
Generally, it is not used alone, but is almost always used as one element of various power transmission circuits. In this case, from the viewpoint of the function, safety, maintenance, inspection, etc. of the entire machine, in practical terms, temporary power interruption and There are many opportunities to connect. In such a case, the power transmission device does not have a power coupling/disconnection function, that is, a clutch function, and cannot satisfy such requirements. The devices shown in FIGS. 3 and 4 have been proposed to solve the above problems.

In the one shown in FIG. 3, a clutch 13 is interposed between the input shafts 8a and 8b, and by engaging and disengaging the clutch 13, the power is transmitted from the input shaft 8a to the planetary roller type power transmission device, and the power is transmitted to the planetary roller type power transmission device. Tsukasa is standing.

In this case, since the clutch 13 is provided, the axial mounting space Lh of the device becomes larger, and
The additional cost of manufacturing the clutch 13 increases the manufacturing cost of the device. In the one shown in FIG. 4, a clutch 14 is interposed between the inner roller 3 and the case 10, and by engaging and disengaging the clutch 14, the inner roller 3 can be fixed or released.

In this case, the radial dimension Lv of the device increases and the manufacturing cost also increases.

In FIGS. 3 and 4, the same members as those in FIGS. 1 and 2 are designated by the same reference numerals.

The present invention has been developed in view of the above, and an object of the present invention is to provide a planetary roller type power transmission device that is lightweight, compact, and inexpensive to manufacture by providing the components of the device with a clutch function.

For this reason, the present invention provides a planetary roller type power transmission device in which an elastic roller is formed so that the radius of the pressure contact surface with the mating roller can be changed by an axial pressing force applied to the side end surface of the inner roller. The pressing force of the elastic roller is increased or decreased by a pressure element pressed against the side surface of the elastic roller and a pressure regulating device connected to the pressure element to attach and detach the pressure contact surface between the elastic roller and the mating roller. It is characterized by its composition.

Since the present invention is configured as described above,
It has the following advantages.

(1) Since the power transmission device has a clutch function in the component itself, which was not possible with conventional planetary roller type power transmission devices of this type, it is lighter and smaller than conventional devices equipped with a clutch device. Therefore, the manufacturing cost of the device is also significantly reduced.

(2) Since the clutch can be engaged and disengaged simply by adjusting the amount of movement of the presser that presses against the side surface of the elastic roller, it is possible to engage and disengage the clutch regardless of whether the power transmission system incorporating the device of the present invention is at rest or in operation. The clutch can be engaged and disengaged at any time, and there is no need to temporarily stop the device to switch the clutch.

(3) If the device of the present invention is combined with a load torque detection device, and if the load torque of the power transmission system exceeds a limit value, the pressurizer is separated from the side of the elastic roller and the clutch is disconnected. , can protect the equipment during overload.

1 of the present invention with reference to FIGS. 5 to 7 below.
To explain the embodiment, 1 is a sun roller fixed to an input shaft 8, 2 is a plurality of planetary rollers (three in this embodiment) supported by a planetary pin 5 via bearings 4, and 6 is a sun roller fixed to an input shaft 8. This is a carrier fixed to the output shaft 20. As shown in FIG. 6, the planetary pin 5 is attached to the carrier 6 in the radial direction by fitting notches 5a provided at both ends into radial grooves 6a formed in the carrier 6. movably supported.

11a, 11b are bearings of the input shaft 8, 12a, 1
2b is a bearing for the carrier 6 and the output shaft 20.

30 is an annular inner roller having a U-shaped cross section, that is, an elastic roller. The elastic roller 30 is made of abrasion-resistant steel material, and as shown in FIGS. 7a and 7b, when the width W is reduced to Wo by applying a pressing force F to both side surfaces 30b, Face 30
The shape is such that the radius of a is reduced. 21a
21a is a front case, 21a is a rear case, and 13 is a bolt for fixing the front and rear cases 21a and 21b.

The elastic roller 30, as shown in FIG.
One end thereof is fixed to the rear case 21b by a pin 18, and the other end side surface 30b is connected to a pressurizer 32 via a bearing 31. The above pressurizer 32
is provided with worm teeth 32a, and a worm 33 meshes with the worm teeth 32a. Further, a screw 32b is provided on the inner periphery of the pressurizing element 32, and is screwed into the front casing 21a. Although not shown, both ends of the worm 33 are pivotally supported by the front casing 21a and
It projects outside of 1a and is connected to an operating device (not shown) for operating the worm 33 via a link.

Reference numeral 17 denotes a spacer inserted into the inner surface of the elastic roller 30, and its width B2 is formed to be slightly smaller than the inner width B1 of the elastic roller 30.

The elastic roller 30 is assembled between the inner periphery 30a and the outer periphery 2a of the planetary roller 2 when the pressurizing element 32 is on the right side of FIG. ) is formed, and it is assembled so that the distance C disappears when it is to the left of this (in the direction of the X arrow).

In the above device, the pressurizer 32 is located on the right side of Figure 5 (Y
in the direction of the arrow), the elastic roller 30 is not pressurized in the axial direction of the rotating shaft, so the inner circumference 30 of the elastic roller 30 is
An assembly gap C is formed between a and the outer periphery 2a of the planetary roller 2, and even if the input width 8 and the sun roller 1 rotate, the planetary roller 2 rotates freely, and the rotation of the input shaft 8 is caused by the output shaft 20. is not transmitted to.

In other words, the clutch is in a disengaged state.

When the worm 33 is rotated, for example, in the direction of the arrow U in FIG.
is rotated around the axis of the input shaft 8 because its worm teeth 32a are engaged with the worm 33. Therefore, the pressurizer 32 has its threaded portion 32
b is screwed onto the front casing 21a, it moves leftward (in the direction of the arrow X) in FIG. 5 and presses the side surface 30b of the elastic roller 30 with a pressing force F. When the pressurizer 32 is further moved in the direction of the arrow X in FIG. 5 and the pressing force F exceeds a certain value, the elastic roller 30
The width W of the planetary roller 2 is reduced, the radius of the inner circumferential surface 30a of the planetary roller 2 is reduced, the inner circumferential surface 30a and the outer circumferential surface 2a of the planetary roller 2 are brought into pressure contact, and a pressing force P is generated.

That is, in FIG. 7, the side surface 3 of the elastic roller 30
When pressing force F is applied to 0a, the axial width W becomes Wo
As a result, the planetary roller 2 of the elastic roller 30
The pressure contact surface 30a forms a crowning deformation E having a radius of curvature τ. (Fig. 7b) This crowning deformation E is formed. (FIG. 7b) The free deformation of this crowning deformation E is restricted by e when the sun roller 1 and the planetary roller 2 are assembled. As a result, a pressing force P corresponding to the free deformation amount e is generated.

The amount of crowning deformation E increases almost in proportion to the pressing force F. Therefore, if the assembly interval C between the elastic roller 30 and the planetary roller 2 is set to be sufficiently small compared to the crowning E, the pressing force F and the pressure contact force P are almost proportional to each other.

When the input shaft 8 and the sun roller 1 rotate in this state, the planetary roller 2 revolves between the sun roller 1 and the inner roller (elastic roller) 30 while rotating.
The carrier 6 and the output shaft 20 rotate in the same direction as the input shaft 8 while being decelerated.

In other words, the clutch is in a fitted state.

Note that excessive displacement of the elastic roller 30 is caused by the spacer 1
7 has come to be regulated.

As described above, the planetary roller type power transmission device according to the present invention can perform a clutch action by changing the pressing force F applied to the side surface 30b of the elastic roller 30.

[Brief explanation of drawings]

1 and 2 show an example of a conventional planetary roller type power transmission device, in which FIG. 1 is a cross-sectional view along the axis of the input shaft, FIG. 2 is a cross-sectional view along the - line in FIG. 1, 3 and 4 are power system diagrams each using a conventional planetary roller type power transmission device.
5 to 7 show one embodiment of the present invention,
Figure 5 is a partial cross-sectional view along the axis of the input shaft;
The figure is a view taken along the - line in FIG. 5, and FIG. 7 is a sectional view of the elastic roller. 1... Sun roller, 2... Planetary roller, 30...
...Inner roller (elastic roller), 8...Input shaft, 6...
...carrier, 20...output shaft, 32...pressure element,
33... Worm, 32a... Worm gear.

Claims (1)

[Scope of utility model registration request] The outer periphery of a sun roller that is connected to one of the rotating shafts so that it cannot move in the circumferential direction thereof, and the inner periphery of an inner roller that is attached to a stationary member so that it cannot move in the circumferential direction of the rotating shaft, respectively. In an apparatus for transmitting power between the two rotating shafts by pivotally supporting a plurality of planetary rollers by a carrier connected to the other rotating shaft, the inner roller is placed in contact with the other roller at the pressure contact surface. one thin-walled cylindrical portion formed with
two thick-walled cylindrical sections that are thicker than the thin-walled cylindrical section and have side end surfaces substantially perpendicular to the axis of the rotating shaft; both ends of the thin-walled cylindrical section and an inner peripheral end of the thick-walled cylindrical section; and a thin disk portion that individually connects the thin cylindrical portion, and the radius of the pressure contact surface is changed by an axial pressing force applied to the side end surface of the thin cylindrical portion. A presser that can be pressed against the side end surface of the roller and can be moved in the axial direction of the rotating shaft; and a presser that is interlocked and connected to the presser and that adjusts the amount of axial movement of the presser from outside the casing. and a pressure regulating mechanism that adjusts the amount of movement to increase or decrease the pressing force against the side end surface of the elastic roller, thereby attaching and detaching the pressure contact surface between the elastic roller and the mating roller. Planetary roller type power transmission device.