JPH0674831B2 - Traction type transmission - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traction type transmission, and more particularly to a traction type transmission capable of smoothly performing a high gear ratio shift.

[0002]

2. Description of the Related Art There are various difficulties in shifting power of high speed rotation by a gear transmission. That is, it is inevitable that an error will occur in the machining of the gear, and the machining error of the gear causes larger vibration and noise as the rotation speed increases.

As a measure for preventing such a gear defect,
Not only precision machining of gears but also various means such as post-machining tooth profile modification, use of expensive ultra-high speed bearings, devising of lubrication method, etc. are required. However, trying to meet all these conditions will lead to higher costs,
It is inevitable that the device will be very expensive.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the problems of the gear transmission described above and to adopt a so-called traction system so that high speed power can be changed smoothly and at a high gear ratio. Another object of the present invention is to provide a traction type speed change device.

[0005]

[Means for Solving the Problems] According to recent research on tribology, in particular, research on elast hydraulic lubrication, when extreme pressure is applied between two surfaces contacting each other in the presence of a special lubricating oil, It has been found that the coefficient of friction momentarily increases by a factor of 2-3.
As a lubricating oil suitable for such an action, for example, "Santork" (trade name) manufactured by Nippon Oil Co., Ltd. has been proposed.

The present invention can achieve the above object by applying such a tribology theory to a planetary roller mechanism having a special structure. That is, the present invention comprises a planetary roller mechanism composed of a sun roller, a plurality of planetary rollers evenly arranged around the sun roller, and an outer ring arranged outside the plurality of planetary rollers. While connecting the roller to the high speed shaft, either one of the outer ring or the planet shaft supporting the planet roller is connected to the low speed shaft, and the planet roller is provided with a large outer diameter portion and small outer diameter portions on both left and right sides thereof. And having a configuration in which the planetary shaft is supported through a gap or is divided into a roller portion on the planetary shaft side and a ring portion on the outer peripheral side concentrically with a gap, The large outer diameter portion is strongly pressed against the outer circumference of the sun roller in the presence of oil, and the outer peripheral surfaces of the small outer diameter portions on the left and right sides are respectively strongly pressed against the inclined surfaces of the outer ring in the presence of oil, thereby Screw one It is characterized in that it has a configuration to press axially towards the small diameter portion by structure.

In the present invention, as a planetary roller mechanism, the planetary roller is revolved without rotating the outer ring, and the planetary shaft is connected to the high speed shaft. There is a case of a so-called star type in which the exterior ring is rotated without being revolved and the exterior ring is connected to a high speed shaft. In the device of the present invention, since the extreme pressure is applied between the sun roller and the planetary roller and between the planetary roller and the exterior ring in the presence of oil, respectively, a large frictional force based on the tribology theory is generated, and thereby a large traction force is generated. Generate. In addition, the planetary roller is supported by a gap with respect to the planetary shaft, or is divided into a roller portion on the planetary shaft side and a ring portion on the outer peripheral side concentrically with a gap. Since the pressing force applied to the planetary roller from does not act on the planetary shaft but only on the sun roller, a large extreme pressure can be efficiently generated.

Further, the planetary roller has a stepped shape having a large outer diameter portion and a small outer diameter portion, and the large outer diameter portion is brought into contact with the sun roller and the small outer diameter portion is brought into contact with the exterior ring. Therefore, a large gear ratio can be obtained at a stretch. Since the small outer diameter portion of the planetary roller and the exterior ring are formed so that their mutual contact surfaces are inclined surfaces, a large extreme pressure can be generated by the wedge action of the inclined surfaces. In this case, the inclined surface of the small outer diameter portion is preferably a crowning surface. In order to generate a pressing force due to the wedge action on this exterior ring, one of the exterior rings on the left and right sides is formed into a ring-shaped piston, and it is pressed by the screw mechanism toward the small outer diameter part of the planetary roller. Has become. It is more preferable that the biasing force of the spring mechanism is further added to the pressing force of the screw mechanism.

The transmission of the present invention does not use a gear mechanism,
Since it is configured based on the roller mechanism, the roundness and smoothness (surface roughness) of the roller are simply used for machining.
It should be processed to raise. Therefore, the occurrence of an error such as gear tooth profile processing is extremely small, and the occurrence of vibration can be easily suppressed even at an extremely high speed rotation. Plural planet rollers are provided, but the number is at least 3
It is advisable to evenly distribute the pieces around the sun roller.
By squeezing the outer circumference of the sun roller with at least three planet rollers, the high-speed shaft connected to the sun roller is inevitably positioned in the center, and the high-speed bearing of the gear transmission, which has been the most difficult to achieve The use can be completely eliminated.

[0010]

1 and 2 show an example of a traction type transmission according to the present invention. In the figure, 10
Reference numeral 0 is a prime mover such as a motor or engine, and 200 is a traction type transmission according to the present invention. Prime mover 100
The drive shaft 13 corresponds to a high speed shaft, and the output shaft 14 of the transmission 200 corresponds to a low speed shaft.

In the above-mentioned device, the sun roller 2 is fixed to the drive shaft 13 and is pressed against the outer periphery of the planetary roller 3 so that the three planetary rollers 3 are evenly arranged. Are arranged so as to come into contact with each other to form a planetary roller mechanism. One of the two exterior rings 4, 40 is integrally formed with the casing 1. On the other hand, the other outer ring 4 is formed as a ring-shaped piston and is movable in the axial direction with respect to the casing 1.

In the planetary roller mechanism described above, each planetary roller 3 is rotatably supported by a planetary shaft 7 via bearings 9. In this shaft support, a small gap 8 is interposed between the bearing surface of the planetary roller 3 and the outer peripheral surface of the retainer of the bearing 9. Each planet shaft 7 is fixed to a carrier 15, and the carrier 15 is integrally connected to an output shaft (low speed shaft) 14. Also, planetary roller 3
Is formed in a stepped shape having a large outer diameter portion 5 and a small outer diameter portion 6, and the small outer diameter portion 6 is formed on both left and right sides of the large outer diameter portion 5.

The planetary roller 3 is arranged so that the large outer diameter portion 5 is pressed against the sun roller 2 with oil interposed therebetween. Further, the outer rings 4 and 40 are pressed against the small outer diameter portions 6 and 6 on both sides so that the inclined surfaces thereof are sandwiched with oil. The outer peripheral surface of the large outer diameter portion 5 has a cylindrical shape parallel to the axial direction, but the outer peripheral surface of the small outer diameter portion 6 is formed into an inclined surface whose radius gradually decreases toward the outer side in the axial direction. Preferably, and more preferably crowned. As the oil interposed between the pressure contact surfaces of the respective rollers, oil having the property of instantaneously increasing the friction coefficient by extreme pressure such as the above-mentioned "Sant track" is used.

An adjusting bolt 10 is screwed into the side wall of the casing 1 so as to penetrate inward and outward, and a pin 11 at the tip of the adjusting bolt 10 is fitted in a fitting hole 12 on the back surface of the piston-shaped exterior ring 4. I am fit. This adjustment bolt 10
Is adapted to press the inclined surface of the exterior ring 4 against the inclined surface of the small outer diameter portion 6 of the planetary roller 3 by adjusting the screw advancement thereof. A spring washer 16 is interposed between the end surface of the adjusting bolt 10 and the back surface of the exterior ring 4, and the biasing force of the spring washer 16 is also applied to the exterior ring 4.

As described above, the pressing force of the outer ring 4 (piston) and the urging force of the spring washer 16 press the small outer diameter portion 6 of the planetary roller 3, so that the outer rings 4 and 40 on the left and right sides are inclined. The surface causes a wedge action on the inclined surfaces of the small outer diameter portions 6 on both sides of the planetary roller 3, so that the large outer diameter portion 5 of the planetary roller 3 is strongly pressed against the sun roller 2. It is desirable that a plurality of such adjusting bolts 10 be provided so as to be evenly arranged on the back surface of the exterior ring 4.

According to the above-described traction-type transmission of the present invention, when the power of the prime mover 100 is transmitted from the drive shaft 13 to the output shaft 14 of the transmission 200 at a variable speed, the large outer portion 5 of the sun roller 2 and the planetary roller 3 is transmitted. Since a large extreme pressure is generated in the presence of oil between the small outer diameter portion 6 of the planetary roller 3 and the outer rings 4 and 40, a large frictional force is instantaneously generated by the tribology theory, and extremely large frictional force is generated. It will generate a large traction force. Further, the planetary roller 3 has a stepped shape with a large outer diameter portion 5 and a small outer diameter portion 6, and the sun roller 2 comes into contact with the large outer diameter portion 5 of the planetary roller 3 to further reduce the small outer diameter portion. Since the exterior rings 4 and 40 are in contact with each other at 6, the high speed power output from the output shaft 13 of the prime mover is output from the output shaft 1
4 is transmitted with a very large reduction ratio.

Moreover, since the above-mentioned transmission is composed of a roller mechanism, a complicated device such as a gear is not required, and a precise device can be easily manufactured. Also,
Since the planetary roller 3 is axially supported by the planetary shaft 7 with a gap 8 therebetween, the pressing force applied in the radial direction from the outer rings 4 and 40 is not applied to the planetary shaft 7. It is possible to directly act on the outer peripheral surface of the sun roller 2. Therefore, a large extreme pressure is easily generated, and a large traction is generated.

In the above-described embodiment, the planetary roller mechanism is a planetary type in which the planetary roller revolves and the outer ring is stationary, but the planetary shaft is fixed and the outer ring is fixed so as not to revolve the planetary roller. It can also be applied to a star type in which a ring is connected to an output shaft so as to rotate. Further, in the above embodiment,
As a structure in which the gap 8 is provided between the planetary roller 3 and the planetary shaft 7, a structure in which the gap between the bearing 9 and the outer periphery of the retainer is used has been exemplified, but this may be configured as shown in FIG. That is, the planetary roller 3 is divided into a central roller portion 3a and an outer peripheral ring portion 3b,
Moreover, a gap 8 is formed between the roller portion 3a and the ring portion 3b.
Is a structure that interposes. With such a configuration, it is possible to advantageously perform power transmission with a higher load.

In each of the above-mentioned embodiments, the case of the reduction gear has been described. However, if the output shaft 14 side is the input shaft and the drive shaft 13 side is the output shaft,
It can be used as a speed increasing device.

[0020]

As described above, according to the present invention, the planetary roller mechanism having a special shape is used, and the extreme pressure according to the tribology theory is generated in the contact portion of the roller to generate a large frictional force. The power of high-speed rotation can be efficiently transmitted at a high gear ratio. Moreover, since it is configured based on rollers without using gears, it does not generate machining errors like gear machining, and it generates vibration even with ultra-high speed power of tens of thousands of revolutions. It is possible to shift smoothly without performing.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a traction type transmission according to an embodiment of the present invention.

FIG. 2 is a view on arrow AA of FIG.

FIG. 3 is a vertical sectional view showing another embodiment of the planetary roller.

[Explanation of symbols]

 100 prime mover 200 traction type transmission 2 sun roller 3 planetary roller 3a roller part 3b ring part 4,40 exterior ring 5 large outer diameter part 6 small outer diameter part 7 planetary shaft 8 clearance 10 adjusting bolt (screw mechanism) 12 fitting hole 16 Spring washer 13 Drive shaft of motor (high speed shaft) 14 Output shaft of reduction gear (low speed shaft)

Claims (1)

[Claims] 1. A planetary roller mechanism comprising a sun roller, a plurality of planetary rollers equally arranged around the sun roller, and an outer ring arranged outside the plurality of planetary rollers. Is connected to a high-speed shaft, and either one of the outer ring or the planet shaft supporting the planet roller is connected to the low-speed shaft, and the planet roller has a large outer diameter portion and small outer diameter portions on both left and right sides thereof. In addition to having the shape
The planetary shaft is supported by a gap, or the roller part on the planetary shaft side and the ring part on the outer peripheral side are concentrically divided by a gap, and the large outer diameter part of the planetary roller is divided by the sun. The outer circumference of the roller is strongly pressed in the presence of oil, and the inclined surfaces of the outer ring are respectively strongly pressed in the presence of oil on the outer circumferences of the small outer diameter portions on both the left and right sides, and one of the outer rings is pressed by the screw mechanism. A traction-type transmission that is configured to press in the axial direction toward the outer diameter portion.