High rotation speed transmission

Abstract

To provide a high rotation speed compatible transmission that reduces vibration and noise, operates without a large load even when the drive machine rotates at high speed, and facilitates the supply of lubricant. A sun roller and a planetary roller in contact with the sun roller; a sun roller bearing through which the sun roller passes and supports the sun roller; a carrier to which the sun roller bearing and a planetary roller bearing supporting the planetary roller are fixed; a ring roller in which the planetary rollers are inscribed and to which an output shaft is fixed; a ring roller bearing that supports the ring roller from the outside; a case that fixes the ring roller bearing from the outside, is coupled to the carrier, and has an output shaft hole through which the output shaft extends.

Description

[Technical Field]

[0001] The present invention relates to a transmission that can stably change speeds even at high rotational speeds and that can easily supply lubricating oil. [Background technology]

[0002] Conventionally, a transmission made up of gears has been used between the driving machine and the driven machine to adjust the rotational speed. However, when speed is changed using gears, the load shared by the teeth fluctuates, resulting in problems of increased vibration and noise. In particular, in recent years, the electrification of driving machines has been progressing from the perspective of CO2 countermeasures. Because it is relatively easy to increase the rotational speed of electric driving machines, the vibration and noise issues of transmissions using gears have become a problem that cannot be overlooked.

[0003] Therefore, it was investigated to adopt a traction drive that uses cylindrical rollers instead of gears to transmit power through the friction of fluid, thereby reducing noise and vibration. Traction drive is a method in which rollers are pressed firmly together instead of gears, and the driving force is transmitted through the viscosity of an oil film when in operation. During actual manufacturing, the rollers are pressed against each other, but it is said that when in operation, they do not come into direct contact due to the oil film.

[0004] Fig. 6 shows a perspective view of the basic configuration of a transmission using a traction drive, and Fig. 7 shows a side cross section. The basic structure of this type of transmission 100 is made up of a sun roller 102, planetary rollers 104, a carrier 106, and a ring roller 108. By fixing any one of the sun roller 102, planetary rollers 104 (carrier 106), or ring roller 108, it becomes possible to increase or decrease speed. Here, we will continue with the explanation of a transmission in which the ring roller 108 is fixed.

[0005] The sun roller 102 is connected to a driving machine (not shown). One or more planetary rollers 104 are provided and are in contact with the sun roller 102. Here, a case is shown in which three planetary rollers 104 are in contact with the sun roller 102. The bearings 114 of the planetary rollers 104 are fixed on the carrier 106. In other words, the relative positions of the planetary rollers 104 do not change. An output shaft 110 is fixed to the carrier 106. The output shaft 110 is then connected to a driven machine (not shown). The inner surface of the ring roller 108 is in contact with the planetary rollers 104.

[0006] When the sun roller 102 rotates in this state, the planetary rollers 104 rotate on their axes. And because the planetary rollers 104 are in contact with the ring roller 108, they rotate along the ring roller 108. That is, the planetary rollers 104 also revolve around the center of the ring roller 108 as their axis. As the planetary rollers 104 revolve, the carrier 106 to which the planetary rollers 104 are fixed also rotates, and the output shaft 110 fixed to the carrier 106 also rotates.

[0007] Here, if the diameter of the sun roller 102 is smaller than the diameter of the planetary rollers 104, the rotation speed of the carrier 106 will be lower than the rotation speed of the sun roller 102, and the output shaft 110 will rotate at a lower rotation speed than the sun roller 102. Patent Document 1 discloses such a traction drive type transmission connected in three stages. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 10-061738 Summary of the Invention [Problem to be solved by the invention]

[0009] In the invention of Patent Document 1, since there is no contact between gears, problems such as vibration and noise are suppressed, but since the planetary roller bearings are fixed to the carrier, there is a problem in that there is no appropriate lubrication method.

[0010] In addition, because the planetary rollers themselves revolve, they are subjected to centrifugal force, which places excessive force on the ring roller and the bearings of the planetary rollers, making them difficult to support. Also, because the rotational moment increases by the amount of centrifugal force of the planetary rollers, a large torque is required to increase the rotational speed of the drive unit (sun roller side), making it difficult to achieve high rotational speeds.

[0011] Furthermore, when using a traction drive, the rollers do not mesh like gears and do not come into direct contact with each other when driven, which causes the rollers to move in the axial direction. [Means for solving the problem]

[0012] The present invention has been devised to solve the above problems, and provides a high-speed transmission that has high lubrication and operates safely and reliably even when the drive machine rotates at high speeds.

[0013] More specifically, the high rotation speed compatible transmission according to the present invention includes: With the solar roller, a planetary roller in contact with the sun roller; a sun roller bearing through which the sun roller passes and supports the sun roller; a carrier to which the sun roller bearing and a planetary roller bearing supporting the planetary roller are fixed; a ring roller in which the planetary rollers are inscribed and to which an output shaft is fixed; a ring roller bearing that supports the ring roller from the outside; The invention is characterized in that it comprises a case that fixes the ring roller bearing from the outside, is connected to the carrier, and has an output shaft hole through which the output shaft extends. [Effects of the Invention]

[0014] The high-speed transmission of the present invention has openings in the carrier that is fixed and exposed to the drive side for providing bearings for the sun roller and planetary rollers, making it easy to supply lubricating oil to the sun roller and planetary rollers.

[0015] Furthermore, since the planetary rollers are supported by a fixed carrier, they do not revolve, making them suitable for the high-speed rotation of the sun roller.

[0016] In addition, since the bearings that support the sun roller and planetary rollers are fixed to a fixed carrier, the use of collars and covers prevents the rollers from moving in the axial direction. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a cross-sectional view showing the configuration of a high rotation speed compatible transmission according to the present invention. [Figure 2] 1 is an assembly diagram of a high rotation speed compatible transmission according to the present invention. [Figure 3] 1A and 1B are perspective views of a high rotation speed transmission according to the present invention as viewed from two directions. [Figure 4] FIG. 2 is an enlarged view of a part of FIG. [Figure 5] FIG. [Figure 6] FIG. 1 is a diagram showing the basic configuration of a conventional traction drive. [Figure 7] FIG. 7 is a side cross-sectional view of FIG. 6. DETAILED DESCRIPTION OF THE INVENTION

[0018] A high rotation speed transmission (hereinafter simply referred to as "transmission") according to the present invention will be described below with reference to drawings and examples. Note that the following description illustrates one embodiment of the present invention and one example, and the present invention is not limited to the following description. The following description can be modified within the scope of the present invention. Furthermore, embodiments and examples obtained by appropriately combining the technical means disclosed in different embodiments and examples are also included in the technical scope of the present invention. Furthermore, all documents described in this specification are incorporated herein by reference. In this specification, when a numerical range is described as "A to B," this means "greater than or equal to A and less than or equal to B."

[0019] Fig. 1 shows a cross-sectional view of a transmission 1 according to the present invention. Fig. 2 shows an assembly diagram of the transmission 1, and Fig. 3 shows a perspective view of the assembled transmission 1. Fig. 3(a) shows the side from which the input shaft (sun roller 2) of the transmission 1 protrudes, and Fig. 3(b) shows the side from which the output shaft 18b protrudes. Please refer to Figs. 1, 2, and 3. The transmission 1 has a sun roller 2, planetary rollers 4, a carrier 6, a ring roller 8, and a case 10.

[0020] The sun roller 2 is a rod-shaped member, one end of which is connected to a driver (not shown). The other end of which is in contact with the planetary roller 4. The sun roller 2 can be said to be the input shaft of the transmission 1. The sun roller 2 is supported by a sun roller bearing 12. The sun roller bearing 12 is fixed to the carrier 6.

[0021] In this specification, when rollers are in contact with each other, it does not only mean that the rollers are actually pressed against each other and come into contact, but also includes a state in which an oil film is formed at the contact point when the rollers are in driving mode and they are not in direct contact.

[0022] The planetary roller 4 is a roller member having a rotation axis (referred to as the "planetary roller rotation axis 4c"), and one or more planetary rollers 4 are provided. Here, the explanation will continue with the case where there are three planetary rollers 4. The planetary rollers 4 are in contact with the sun roller 2. The planetary rollers 4 are supported by planetary roller bearings 14. The planetary roller bearings 14 are fixed to the carrier 6. In other words, the planetary rollers 4 are supported on one side with respect to the carrier 6.

[0023] The carrier 6 is a roughly disc-shaped member that has a sun roller hole 6a in its center through which the sun roller 2 extends and a planetary roller hole 6b to which the planetary roller bearing 14 is fixed. The sun roller bearing 12 is fixed in the sun roller hole 6a.

[0024] The ring roller 8 is a ring-shaped member, with the three planetary rollers 4 in contact with its inner surface. The ring roller 8 is supported from the outside by a ring roller bearing 16. Here, the "outside" refers to the outer peripheral surface side of the ring roller 8. The outer peripheral surface side of the ring roller 8 also refers to the surface farther from the rotation axis of the ring roller 8, and the rotation axis of the ring roller 8 coincides with the rotation axis of the sun roller 2.

[0025] An output shaft member 18, which has an output shaft 18b formed at the center of a disk-shaped member 18a, is screwed to the ring roller 8. That is, the output shaft member 18 is composed of the disk-shaped member 18a fastened to the ring roller 8 and the output shaft 18b, and the rotation of the ring roller 8 can be taken out from the output shaft 18b. The disk-shaped member 18a and the output shaft 18b may be separate members, or may be an integrated member machined from the same material. The disk-shaped member 18a may be hollowed out to reduce the rotational moment.

[0026] The case 10 is a cylindrical member closed on one side, with an output shaft hole 10a provided in the center of the bottom surface. An output bearing 24 is fixed in the output shaft hole 10a. The open end is fixed with the carrier 6 acting as a lid. That is, the planetary rollers 4, ring roller 8, ring roller bearing 16, and disk-shaped member 18a of the output shaft member 18 are housed inside the carrier 6 and case 10. The ring roller bearing 16 is fixed from the outer circumferential surface side by the edges of the carrier 6 and case 10.

[0027] With this structure, when the sun roller 2 rotates at high speed, the planetary rollers 4 do not revolve around the sun roller 2, so no centrifugal force is generated by the planetary rollers 4. Furthermore, the ring roller 8 that rotates the output shaft 18b rotates, but because it rotates while being supported by the ring roller bearing 16 that is supported from the outside by the case 10 and the carrier 6, the force does not escape to the outside, and stable rotation can be maintained.

[0028] Figure 4 shows an enlarged view of the carrier 6, sun roller bearing 12, and planetary roller bearing 14 in Figure 1. Figure 5 shows a more detailed assembly diagram of the carrier 6. Note that the sun roller 2 and planetary rollers 4 have been omitted from Figure 5. When viewed as part of the transmission 1, the side of the carrier 6 from which the sun roller 2 protrudes is called the front side of the carrier 6, and the opposite side is called the back side of the carrier 6.

[0029] The sun roller bearing 12 is inserted into the sun roller hole 6a from the front side of the carrier 6. The sun roller hole 6a is formed so that its inner diameter becomes small when it is pushed in by the height of the sun roller bearing 12. Therefore, any further movement of the sun roller bearing 12 from the front side to the back side of the carrier 6 is restricted.

[0030] Meanwhile, a sun roller bearing lid 30 having a through hole (sun roller shaft lid hole 30a) smaller in diameter than the sun roller bearing 12 is fastened to the carrier 6 around the sun roller hole 6a on the front side of the carrier 6. This sun roller bearing lid 30 restricts movement of the sun roller bearing 12 from the back side to the front side of the carrier 6. In other words, the movement of the sun roller bearing 12 is restricted by the carrier 6 and the sun roller bearing lid 30.

[0031] The sun roller 2 is formed so that when it is inserted into the sun roller bearing 12 from the back side of the carrier 6, the diameter on the side that comes into contact with the planetary roller 4 is larger than the protruding tip (2b). Therefore, movement is restricted from the sun roller bearing 12, whose movement is restricted, to the front side of the carrier 6. In addition, the sun roller 2 has a sun roller shaft collar 32 fixed at a point on the front side of the carrier 6, further than the sun roller bearing cover 30.

[0032] The outer diameter 32φ of the sun roller shaft collar 32 is larger than the hole diameter 30aφ of the sun roller shaft cover hole 30a. Therefore, the movement of the sun roller 2 is restricted to the back side of the carrier 6 due to interference between the sun roller shaft collar 32 and the sun roller shaft cover hole 30a. In other words, the movement of the sun roller 2 is restricted by the sun roller bearing 12 and the sun roller shaft collar 32.

[0033] Next, the planetary roller bearings 14 are inserted into the planetary roller holes 6b from the back side of the carrier 6. The planetary roller holes 6b are formed so that their diameter decreases midway from the back side to the front side of the carrier 6 (at the point indicated by the symbol 6ba). Therefore, movement of the planetary roller bearings 14 toward the front side is restricted at this point. Meanwhile, a planetary roller bearing cover 34 with a through hole (planetary roller shaft cover hole 34a) is arranged around the planetary roller hole 6b on the back side of the carrier 6. The planetary roller rotation shaft 4c can pass through this planetary roller shaft cover hole 34a, but since it is smaller than the outer diameter 14φ of the planetary roller bearing 14, the planetary roller bearing 14 cannot pass through it.

[0034] A planetary roller shaft collar 36 is fixed to the end of the planetary roller rotation shaft 4c. The outer diameter of the planetary roller shaft collar 36 is formed to be larger than the inner diameter of the planetary roller bearing 14. In other words, the planetary roller shaft collar 36 interferes with the planetary roller bearing 14, restricting the movement of the planetary roller 4 to the back side of the carrier 6.

[0035] Furthermore, movement of the planetary rollers 4 toward the front side of the carrier 6 is restricted by the planetary roller bearing cover 34. Therefore, the movement of the planetary rollers 4 is restricted by the planetary roller shaft collar 36 and the planetary roller bearing cover 34.

[0036] As described above, the axial movement of the sun roller 2, planet roller 4, sun roller bearing 12, and planet roller bearing 14 is restricted by the sun roller hole 6a and planet roller hole 6b, which are provided in the carrier 6 and whose diameter changes along the way, the sun roller bearing cover 30, the sun roller shaft collar 32, the planet roller bearing cover 34, and the planet roller shaft collar 36.

[0037] Furthermore, since the sun roller holes 6a and the planetary roller holes 6b are provided in the carrier 6, which is fixed and does not rotate, it becomes extremely easy to supply lubricating oil from the front side of the carrier 6. [Industrial Applicability]

[0038] The transmission according to the present invention can be suitably used to reduce the rotation speed of a high-speed rotating driving machine such as an electric motor. [Explanation of symbols]

[0039] 1. Transmission 2 Sun roller (input shaft) 4 Planetary Rollers 4c Planetary roller rotating shaft 6. Career 6a Solar roller hole 6b Planetary roller hole 8 Ring Roller 10 cases 12. Sun Roller Bearing 14 Planetary roller bearing 16 Ring roller bearing 18a Disk-shaped member 18b Output shaft 18 output shaft member (disk-shaped member 18a + output shaft 18b) 10a (of the output shaft member 18) output shaft hole 24 Output bearing 30 Solar roller bearing cover 30a Cover hole for solar roller shaft 32 Sun roller with shaft collar 34 Planetary roller bearing cover 34a Planetary roller shaft cover hole 36 Planetary roller with shaft collar

Claims

1. With the solar roller, a planetary roller in contact with the sun roller; a sun roller bearing through which the sun roller passes and supports the sun roller; a carrier to which the sun roller bearing and a planetary roller bearing supporting the planetary roller are fixed; a ring roller in which the planetary rollers are inscribed and to which an output shaft is fixed; a ring roller bearing that supports the ring roller from the outside; a case that fixes the ring roller bearing from the outside, is coupled to the carrier, and has an output shaft hole through which the output shaft extends.

2. a sun roller bearing cover that is fixed between the sun roller bearing and the carrier and has a cover hole for a sun roller shaft; 2. A high rotation speed transmission according to claim 1, further comprising: a sun roller shaft collar fixed to said sun roller and larger than said sun roller shaft cover hole.

3. a planetary roller bearing cover that is fixed between the planetary roller bearing and the carrier and has a cover hole for a planetary roller shaft; 2. A high rotational speed transmission according to claim 1, further comprising: a planetary roller shaft-mounted collar fixed to said planetary roller and having a diameter larger than an inner diameter of said planetary roller bearing.

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