JPH0214577B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes a sun roller fixed to an input shaft;
an inner roller fixed to the casing around it;
The present invention relates to a planetary roller type power transmission device comprised of a sun roller pivotally supported on the output shaft side and a plurality of planetary rollers disposed between inner rollers.

A plurality of planetary rollers are circumscribed on the circumferential surface of the sun roller, and an inner roller fixed to the casing is inscribed on the outside of the planetary rollers, and the revolution speed of the planetary roller when the sun roller side is the input axis is calculated. Figure 1 shows a conventional rolling transmission device that takes out the output shaft.
2, 1 is a sun roller directly connected to the input shaft 8 and driven, 13 is a bearing of the input shaft 8, and 2 is shown in FIG.
is a planetary roller rotatably supported on a pin 5 via a bearing 4, and a plurality of output shafts 11 are attached to the carrier 6 and supported by a bearing 14.
It is designed to revolve above the Earth. 3 is an inner roller which is connected to the surrounding casing 10 via a pin 9.
and the plurality of planetary rollers 2
A shim 15 of an appropriate thickness is inserted between the cover 16 attached to the casing 10 with bolts 12 and the inner roller side surface 3b, and a pressing force T is applied to the inner roller 3. The pressure contact force P generated by this causes a frictional force in the rotational direction to transmit power.

Further, the mechanism for generating the above-mentioned pressing force P will be explained with reference to _FIG . Thin cylindrical portion 3a of
is elastically deformed and protrudes in an arch toward the inner diameter side, resulting in crowning C', which causes the inner diameter of the inner roller 3 to
Reduce from Di to Dm. However, since the planetary roller 2 and the sun roller 1, which are sufficiently rigid, are inscribed on the inner diameter side, the crowning is restrained by C'-h and a pressing force P is generated. Note that h is the initial gap in the radial direction that exists in the free state where the pressing force P is not applied.

Therefore, in the conventional planetary roller type power transmission device as described above, the diameter Ds of the sun roller 1 is configured to be smaller than the diameter Dp of the planetary roller 2 in order to increase the speed reduction ratio or speed increase ratio.
Comparing the rotational speeds of the bearing 4 of the planetary roller 2, the bearing 13 of the input shaft 8, and the bearing 14 of the output shaft 11, it is found that the bearing 13 rotates at the highest speed. It is necessary to make the bearing sufficiently practical in terms of reliability and durability, but there are limits to the modification of the bearing, and the performance of the bearing 13 limits the usage conditions as a device. have.

The present invention aims to solve the above-mentioned difficulties in conventional planetary roller type power transmission devices. In a planetary roller type power transmission device in which a plurality of planetary rollers are pivotally supported by connected carriers, a second sun roller is fixed to the input shaft in addition to the sun roller, and the second sun roller is fixed to the input shaft. It is characterized in that a plurality of second planetary rollers are disposed between the second sun roller and the second inner roller fixed to the casing, and its purpose is to By eliminating the bearing of the input shaft on the sun roller side that rotates at the highest speed, the factors that limit the use of the bearing are removed, and a certain amount of radial load and thrust load can be applied to the end of the input shaft. The object of the present invention is to provide an acceptable planetary roller type power transmission device.

The present invention has the above-mentioned configuration, and a plurality of rollers are supported between the sun roller fixed to the input shaft and the inner roller fixed to the surrounding casing, and are pivotally supported by a carrier connected to the output shaft. In addition to the power transmission system in which the planetary rollers of Since a plurality of second planetary rollers are disposed between the carriers connected to the output shaft and supported by support plates independent of the carrier, two of the roller sets of the sun roller, planetary rollers, and inner rollers are disposed between the carriers connected to the output shaft. The pair of rollers is arranged on the input shaft side, and the roller set uses rolling contact motion with the planetary roller accompanying rolling conduction to replace the bearing function of the input shaft that shares the rotation center of the sun roller. It has a bearing function that can sufficiently handle the high-speed rotation of the shaft, and is capable of supporting radial and thrust loads, ensuring reliability and durability and allowing the equipment to be used in high-speed ranges. be able to.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 3 shows a first embodiment of the present invention, in which 1,
1' is the outer diameter directly connected to the input shaft 8.
The sun rollers Ds and Ds′ and the second sun roller 2 are planetary rollers with an outer diameter Dp that are circumscribed to the sun roller 1, and are rotatably supported on a pin 5 via a bearing 4. At least three pins 5 are arranged around the output shaft 11 and the output shaft 11 is supported by a bearing 14. 2' is the second
A second planetary roller having an outer diameter Dp' that circumscribes the sun roller 1', is rotatably supported on a pin 5' via a bearing 4', and is mounted around the support plate 7 of the pin 5'. At least three of them are arranged and revolve around the input shaft 8. 3, 3' are inner rollers,
A second inner roller, in which a planetary roller 2 and a second planetary roller 2' are respectively inscribed, and
It is fixed to the surrounding casing 10 via pins 9, 9'. The cover 13 is attached to the casing 10 by bolts 12 and is attached to the inner roller 3.
A spacer 16 is interposed between the inner roller 3' and the second inner roller 3' to maintain an appropriate distance L, and a shim 15 of an appropriate thickness is installed between the inner roller 3 and the second inner roller 3'.
Pressure forces P and P' act on the inner roller 3' of the second sun roller 1' and the second sun roller 1' and the second sun roller 1' and the second sun roller 1' and the inner roller 3, respectively. The structure is such that a pressing force P' is generated in a second roller set of two planetary rollers 2' and a second inner roller 3'.

The first embodiment shown in FIG. 3 has the above-described structure, so that the contact force P acting between the sun roller 1, planetary roller 2, and inner roller 3 in the roller set is generates a frictional force between the rollers, thereby transmitting power between the input shaft 8 and the output shaft 11.

A second sun roller 1', a second planetary roller 2', and a second inner roller 3', which are in the second roller set.
The pressing force P' acting between the input shaft 8 and the output shaft 11 is not directly involved in the power transmission between the input shaft 8 and the output shaft 11, but is applied to the second inner roller whose center position in the radial direction is correctly regulated by the casing 10. 3' and at least three second planetary rollers 2' inscribed therein, it plays a role of regulating the center of rotation of the second sun roller 1' which is in contact therewith via at least three second planetary rollers 2'.

On the other hand, the rotation center of the sun roller 1 is the planetary roller 2.
It is indirectly regulated by the bearing 14 via.

Further, the relationship between the rotational speeds of each member in the above embodiment is as follows: n ₆ : rotational speed of the carrier 6 n ₇ : rotational speed of the support plate 7 n ₈ : rotational speed of the input shaft 8 D _i : rotational speed of the planetary roller 2 Outer diameter D _s : Diameter of sun roller 1 D' _i : Outer diameter of second planetary roller 2'D' _s : Diameter of second sun roller 1' R=Di/Ds (1) R'= D′ _i /D′ _s …(2), then n ₆ = n ₈ 1/(R+1) …(3) n ₇ = n ₈ 1/(R′+1) …(4) Completed, carrier 6 and support plate 7
are independent members, so it is not necessary that n ₆ =n ₇ and the diameter ratio R' can be set arbitrarily regardless of R.

Therefore, in order to improve the load capacity for the external radial load R _a on the input shaft 8 side, D' _i > D _i , D' _p >
It is also free to configure such that D _p , D′ _s >D _s .

With the above structure, the external radial load _{R a} acting on the shaft end of the input shaft 8 is reduced by two pairs of rollers,
That is, sun roller 1 - planetary roller 2 - inner roller 3
It is supported by the second sun roller 1', the second planetary roller 2', and the second inner roller 3'. Further, a certain amount of external thrust load A is supported by the collar 1a or 1b of the sun roller 1, via the planetary roller 2 and the carrier 6, and by the bearing 14.

Therefore, due to the structure and operation described above, the input shaft 8, which generally rotates the highest in the device, does not require a conventional bearing, and high-speed rotation is relatively easily possible and durability is improved. Performance and reliability are also significantly improved.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made without departing from the spirit of the present invention. .

[Brief explanation of drawings]

Figure 1 is a longitudinal cross-sectional view of a conventional planetary roller power transmission device (the lower part is partially omitted), and Figures 2A and B are the
FIG. 3 is a longitudinal sectional view showing the first embodiment of the present invention. 1: sun roller, 1': second sun roller,
2: Planetary roller, 2': Second planetary roller, 3:
Inner roller, 3': second planetary roller, 4, 4', 1
4: bearing, 5, 5': pin, 6, 6a, 6b: carrier, 7: support plate, 8: input shaft, 9, 9': pin, 10: casing, 11: output shaft, 15: shim.

Claims (1)

[Claims] 1 Planetary roller type power with a plurality of planetary rollers supported by a carrier connected to the output shaft between a sun roller fixed to the input shaft and an inner roller fixed to the surrounding casing. In the transmission device, a second sun roller is fixed to the input shaft in addition to the sun roller, and a plurality of rollers are provided between the second sun roller and a second inner roller fixed to the casing. A planetary roller type power transmission device, characterized in that a second planetary roller is provided, and the second planetary roller is pivotally supported by a support plate independent of a carrier connected to the output shaft.