BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure relates to a transmission and a compressor system.

Priority is claimed on Japanese Patent Application No. 2020-002441, filed on Jan. 9, 2020, the content of which is incorporated herein by reference.

Description of Related Art

Japanese Unexamined Patent Application, First Publication No. H9-112642 discloses a configuration of a planetary roller type power transmission device in which a plurality of planetary rollers are disposed between an inner peripheral surface of an outer ring disposed concentrically and a sun roller, and a carrier supporting a support shaft of the planetary roller is used as an output shaft. In this configuration, lubricating oil is supplied to a contact portion between the planetary roller and the outer ring.

SUMMARY OF THE INVENTION

However, in the above configuration, a lubricating oil supply mechanism for supplying the lubricating oil to the contact portion between the planetary roller and the outer ring or a bearing which rotatably supports the outer ring and the carrier is required. Therefore, in order to use the planetary roller type power transmission device for a long period of time, maintenance such as supplying the lubricating oil to the lubricating oil supply mechanism is required, which is troublesome.

Further, if a rotation speed increases to support a high-speed operation, the lubricating oil may flow outward in a circumferential direction due to a centrifugal force, and thus, lubricity may be impaired. Further, when a temperature of the lubricating oil increase, the lubricity is impaired, and thus, a rotational speed may be limited.

The present disclosure provides a transmission and a compressor system capable of suppressing a use of lubricating oil, facilitating maintenance, and increasing a rotation speed.

According to an aspect of the present disclosure, a transmission is provided including: a housing, a first radial bearing which is dry-type and is fixed to the housing; a first shaft which is supported by the first radial bearing to be rotatable around an axis with respect to the housing; a ring member which is accommodated inside the housing, has a cylindrical shape extending axial direction in which the axis extends, and is connected to an end portion of the first shaft so as to rotate around the axis together with the first shaft; a second radial bearing which is dry-type and is fixed to the housing on a side opposite to the first radial bearing in the axial direction in a state where the ring member is interposed therebetween; a sun roller which is disposed inside the ring member in a radial direction about the axis and has a columnar shape about the axis; a second shaft which extends from the sun roller to a first side in the axial direction and is rotatably supported around the axis by the second radial bearing; a plurality of planetary rollers which formed in a columnar shape and are disposed at intervals in a circumferential direction around the axis in a state of being in contact with an inner peripheral surface of the ring member and an outer peripheral surface of the sun roller; and a planetary roller supporting member which rotatably supports each of the plurality of planetary rollers around a roller axis of each of the plurality of planetary rollers and restrains a movement of each of the plurality of planetary rollers in the circumferential direction, in which the ring member is in contact with the plurality of planetary rollers in a state of pressing the plurality of planetary rollers inward in the radial direction so that the plurality of planetary rollers face the sun roller.

According to another aspect of the present disclosure, a compressor system is provided including: a compressor; a driving machine which drives the compressor; and the transmission which is provided between the compressor and the driving machine.

According to the transmission and compressor system of the present disclosure, it is possible to suppress use of lubricating oil, facilitate maintenance, and increase a rotation speed.

