JP2000240661A - Roller with retainer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a roller with a retainer capable of stably guiding a roller, obtaining high load capacity, excellent in lubricity and preventing the roller from slipping off to the outside. SOLUTION: A retainer 1 is cylindrical and provided with pockets 3 formed in plural places in the circumferential direction. A column part 4 between pockets 3, 3 is formed thin by an inner peripheral groove 5 having a diameter larger than the pitch circle diameter PCD of roller array. The thin part 4a is provided with a projection 6 formed to prevent a roller 2 from slipping off to the outside. Both side portions of the thin part 4a in the column part 4 are taken as roller guide parts 4b. The inside diameter D1 of the roller guide part 4b is a little larger than the pitch circle diameter PCD.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller with a cage suitable for a part requiring a high load capacity such as a planetary reduction gear.

[0002]

2. Description of the Related Art FIG. 8 shows a conventional bearing for a portion requiring a high load capacity such as a planetary reduction gear. This is an annular cage 5 having flanges 51b at both ends in the axial direction.
1 and a roller 52 placed in a pocket 53 of the retainer 51. Pillar 57 between pockets 53
In order to increase the number of rollers 52 as much as possible, they are provided only in the outer diameter portion of the cage, and are formed to be thin in the radial direction. That is, on the outer diameter side of the retainer, since the interval between the adjacent rollers 52 is relatively large, the column portion 57 is provided so as to be located only at the outer diameter side portion. Further, the roller stopper projections 54 are provided only on the outer diameter side.

[0003]

In the retainer 51 shown in FIG. 1, the rollers 52 are guided by the side surfaces (guide portions A) of the pillars 57. However, as described above, the number of the rollers is increased. 5
Since 7 is formed thin, the rollers 52 are guided only at the upper part. For this reason, the guide is insufficient, and the rollers 52 are easily inserted into the retainer 51. It is difficult to provide the column portion 57 up to the inner diameter side for stable guidance because of processing limitations, and it is not preferable from the viewpoint of ensuring the flow of lubricating oil.

SUMMARY OF THE INVENTION An object of the present invention is to provide a roller with a cage capable of guiding rollers stably, obtaining a high load capacity, excellent in lubricity, and capable of preventing the rollers from coming off to the outer diameter side. To provide. Another object of the present invention is to prevent a roller from interfering with an adjacent planetary gear even when used in a planetary gear reduction device with a crank.

[0005]

A roller with a retainer according to the present invention comprises a retainer and a plurality of rollers. The retainer has a cylindrical shape and has pockets formed at a plurality of positions in a circumferential direction.
The axial center part of the pillar between the pockets is formed thin by an inner circumferential groove having a diameter larger than the pitch circle diameter of the roller arrangement, and a protrusion for preventing the roller from coming off outward is formed on the thin part. It is formed. The portions on both sides of the thin portion in the pillar portion,
Roller guides are provided, and the inner diameter of each roller guide is slightly larger than the pitch circle diameter. According to this configuration, each roller in the pocket is guided by the roller guides on both sides of the thin portion. The roller guide section is formed to have an inner diameter slightly larger than the pitch circle diameter of the roller array, has a certain thickness, and is provided at both ends of the roller, so that stable roller guideability is obtained. Can be In addition, since the inner diameter of the roller guides is larger than the pitch circle diameter of the roller arrangement, the roller guides are located at locations where the gap between adjacent rollers is relatively large. As much as possible, a load capacity as large as possible can be obtained in a limited space. Since the space between the roller guides on both sides is a thin portion, unlike the one that forms a thick roller guide over the entire length of the column, a space through which lubricating oil flows is easy to obtain,
Good lubricity. A retainer projection is provided on the outer diameter side of the retainer to prevent the roller from coming off. However, since this projection is provided in the thin portion, it is unlikely to hinder the flow of the lubricating oil. For these reasons, loss of rotation torque can be prevented.

In the present invention, the roller diameter is dw, the number of rollers is n, the pitch circle diameter of the roller array is PCD, and when (dw × n) / (π × PCD) ≧ 0.8, the roller guide portion is The inner diameter may be larger than the roller pitch circle diameter. When the product of the roller diameter dw and the number n becomes equal to or more than 80% of the pitch circle diameter, the width of the pillar portion becomes narrower and processing becomes difficult, but the portion larger than the pitch circle diameter compares the width of the pillar portion. You can get big. Therefore, in the case of the above-described condition of the roller diameter and the number of rollers, if the inner diameter of the roller guide portion is larger than the pitch circle diameter of the roller arrangement,
There is an effect that processing becomes easy.

In the present invention, an annular outer peripheral groove may be formed in the axially central portion of the thin portion. By forming the outer peripheral groove in this way, the flow of the lubricating oil becomes good, and the lubricity is improved. Therefore, torque loss is small. Since the width of the outer circumferential groove is shorter than the width of the inner circumferential groove, a decrease in strength of the column portion can be suppressed.

In the present invention, the thin portion of the pillar portion and the length portions serving as the roller guide portions on both sides of the pillar portion are formed such that the pocket opening edge side of the outer diameter side has a pitch circle larger than the outer diameter surface position of the retainer annular portion. It may be located on the side. Thereby, the action of scraping the lubricating oil by the edge of the pocket opening edge is reduced, and torque loss during rotation is prevented.

In the present invention, a surface pushing portion having an inclination angle of 30 to 100 ° may be formed in the roller guide portion and the thin portion of the pillar portion. In this way, by forming the surface pushing portion having a shape along the outer diameter surface of the roller, the stable guideability of the roller is further improved. In the present invention, the gap between the thin portion of the pillar portion and the outer diameter surface and the gap between the roller guide portions on both sides of the thin portion and the outer diameter surface may be substantially equal to each other.

In the present invention, the retainer may be cylindrical and have a gate-shaped cross-sectional shape having flanges extending radially inward at both axial ends. Providing the retainer with the flange in this way prevents the rollers from interfering with the adjacent planetary gears even when used in, for example, a planetary gear reduction device with a crank.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. The roller with a cage includes a cage 1 and a plurality of rollers 2. The retainer 1 is cylindrical, has a portal-shaped cross-sectional shape having flanges 8 extending radially inward at both ends in the axial direction, and has pockets 3 formed at a plurality of positions in the circumferential direction. The pillar portion 4 between the pockets 3 is formed at its axial center portion to be thin by an inner circumferential groove 5 having a diameter larger than the pitch circular diameter PCD of the roller arrangement. Protrusions 6 are formed to prevent the protrusions from coming off. The pillar portion 4 has a roller guide portion 4 on both sides except the thin portion 4a.
b. The inner diameter D1 of the roller guide 4b is slightly larger than the pitch circle diameter PCD. In this example, the number of the protrusions 6 is one, and is provided at the center of the thin portion 4a so as to extend to near both ends thereof. However, a plurality of protrusions 6 may be provided as shown in FIG. An annular outer circumferential groove 7 having a width shorter than that of the inner circumferential groove 5 is formed at the axial center of the thin portion 4a.

The relationship among the roller diameter dw, the number of rollers n, and the pitch circle diameter PCD is such that (dw × n) / (π × PCD) ≧ 0.8.

As shown in the enlarged view of FIG. 3, the length of the pillar guide 4b of the column 4 is a so-called chamfer on the side 4ba of the pocket opening on the outer diameter side. 1a is located closer to the pitch circle than the outer diameter surface position S. The length of the thin portion 4a of the pillar portion 4 including the tip edge 6a of the projection 6 is also the pocket opening edge side 4aa on the outer diameter side surface.
(FIG. 2) is a chamfered portion and is located on the pitch circle side of the outer diameter surface position S of the retainer annular portion 1a. As described above, the processing of making each edge 4aa, 4ba, 6a a chamfered part is performed by face pressing by a press or tumbling. Note that the retainer 1 in this embodiment is made of metal. The gap α between the thin portion 4a of the pillar portion 4 and the outer diameter surface (FIG. 3A), and the roller guide portions 4b on both sides of the thin portion 4a
However, the gap β with the outer diameter surface may be substantially equal to each other.

According to this configuration, each roller 2 in the pocket 3 is guided by the thin portion 4a and the roller guide portions 4b on both sides of the thin portion 4a. The roller guide portion 4b is formed so that the inner diameter D1 is slightly larger than the pitch circular diameter PCD of the roller arrangement, has a certain thickness in the radial direction, and is provided at both ends of the roller 2, Stable roller guidance is obtained. Since the inner diameter D1 of the roller guide 4b is larger than the pitch circle diameter PCD, the roller guide 4b is located at a position where the gap between the adjacent rollers 2 is relatively large. Therefore, increase the number of rollers 2 as much as possible,
A load capacity as large as possible can be obtained in a limited space. That is, as the number of rollers increases, the column width decreases. In particular, when the relationship among the roller diameter dw, the number of rollers n, and the pitch circle diameter PCD becomes (dw × n) / (π × PCD) ≧ 0.8. However, there is a problem of processing limit. Therefore, in the case of the above-mentioned relation, the roller guide portion 4 of the inner diameter D1 is used.
The effect of providing b is great. If the relation of the above formula is not satisfied, the roller guides 4
The inner diameter D1 of b may be equal to or less than the pitch circle diameter PCD.

In the present invention, the roller guides 4 on both sides are provided.
Since the portion between b and 4b is a thin portion 4a, unlike the one forming a thick roller guide portion over the entire length of the column portion 4,
Easy to obtain space for lubricating oil flow and good lubricity. Cage 1
A protrusion 6 is provided on the outer diameter side to prevent the rollers from coming off. However, since the protrusion 6 is provided on the thin portion 4a, it is unlikely to hinder the flow of the lubricating oil. Since the outer peripheral groove 7 is provided in the thin portion 4a, the flow of the lubricating oil can be favorably obtained. Further, as shown in FIG. 3 (A), since the respective edge portions 4aa, 4ba, 6a of the pillar portion 4 are located on the pitch circle side from the outer diameter surface position S of the retainer annular portion 1a, the pocket opening edge The effect of scraping off the lubricating oil by the edge of is reduced. For these reasons, loss of rotation torque can be prevented.

In the above embodiment, as shown in FIG. 3 (B), the roller guide portion 4b and the thin portion 4a of the column portion 4 are provided with a surface pressing portion 4bb having an inclination angle of 30 to 100 °.
May be formed. Thereby, the stability and smoothness of the guide of the roller 2 are further improved. In each of the above embodiments, the flange 8 may not necessarily be provided depending on the purpose of use. For example, as shown in FIG. 5, the inner diameter of the retainer annular portion 1a is made equal to the inner diameter of the roller guide portion 4b. Is also good. The flange 8 of the retainer 1 has a function of preventing the rollers from interfering with the adjacent planetary gears when used in the following planetary gear reduction device with a crank.

FIGS. 6 and 7 show an example of a planetary gear reduction device to which the roller with a cage according to the present invention is applied. The planetary gear reduction device includes an internal gear sun gear 21, a carrier 22 serving as a rotation output unit, and a crankshaft 23 rotatably supported by the carrier 22 and having a plurality of eccentric shaft portions 23a and 23b adjacent thereto. , Each eccentric shaft portion 2 of this crankshaft 23
It has a plurality of planetary gears 24 and 25 rotatably mounted on the sun gears 3 a and 23 b and meshes with the sun gear 21, and a rotation input unit 26 for inputting rotation to the crankshaft 23. Sun gear 2
1 is fixed to a housing 27, and the carrier 22 is mounted on the housing 27 via a bearing 28 (FIG. 7) so as to be rotatable concentrically with the sun gear 21. Rotation input unit 2
Reference numeral 6 denotes an input shaft 29 concentric with the sun gear 21 and a transmission gear 30 provided on each crankshaft 23 and meshing with a gear portion of the input shaft 29. The crankshafts 23 are provided at a plurality of positions (for example, three positions) in the circumferential direction of the carrier 22. As shown in FIG. 7, the planetary gears 24 and 25 are respectively mounted on eccentric shaft portions 23a and 23b of the crankshaft 23 via rollers 31 with retainers. The roller with a cage of the present invention, for example, the roller with a cage of the embodiment of FIG. 1 is used as the roller with a cage 31.

The operation of the planetary gear reduction device will be described.
When the input shaft 29 at the center is rotated, the three crankshafts 23 rotate via the transmission gear 30 in synchronization with each other. Here, the first-stage deceleration is performed. The crankshaft 23 and the planetary gears 24 and 25 are connected via a roller 31 with a retainer.
4 and 25 synchronize with the combined motion of the revolution and the rotation when the inner gear rotates inside the sun gear 21 having the internal teeth. The two planetary gears 24 and 25 arranged in the axial direction revolve around the inner periphery of the internal sun gear 21 with a phase shift of 180 ° from each other. Therefore, the inertial force due to the whirling of the two planetary gears 24 and 25 cancels each other. The internal gear sun gear 21 is fixed, and the planet gear 2
Reference numerals 4 and 25 rotate around the inner periphery of the internal gear sun gear 21. The three crankshafts 23 are sandwiched between two disk portions 22a and 22b of the carrier 22 serving as an output member. Therefore,
The revolution of the planetary gears 24 and 25 reaches the carrier 22 through the revolution of the crankshaft 23, and a reduced rotational motion is obtained.

In the planetary gear reduction device of this configuration, a large load acts on the rollers 31 with cages interposed between the planetary gears 24 and 25 and the crankshaft 23, and the installation space for the rollers 31 with cages is small. However, the space is limited in order to avoid an increase in the size of the entire reduction gear transmission. In addition, the cage of the roller 31 with the cage is formed by the adjacent planetary gears 24 and 2
5 in sliding contact. However, according to the rollers with cages of the above embodiments, a large load capacity can be obtained in a limited space, and since the cage 1 has the flange 8, adjacent planets eccentric to each other. The sliding contact of the gears 24, 25 with the width surfaces does not cause a problem of interference with the inner diameter surfaces of the planetary gears 24, 25.

[0020]

According to the roller with cage of the present invention, the axial center portion of the column between the pockets is formed thin by an inner circumferential groove having a diameter larger than the pitch circle diameter of the roller arrangement. ,
Protrusions are formed to prevent the rollers from slipping outward, and the portions on both sides of the thin portion in the pillar portion serve as roller guides, and the inner diameter of the roller guides is slightly smaller than the pitch circle diameter. Since the roller is made large, stable guidance of the roller is possible, a high load capacity can be obtained, excellent lubricity, and the roller can be prevented from coming off to the outer diameter side.
If the cage has a portal-shaped cross section having flanges extending radially inward at both ends in the axial direction, the rollers interfere with the adjacent planetary gears even when used in a planetary gear reduction device with a crank. Never do.

[Brief description of the drawings]

FIG. 1A is a partially cutaway side view of a roller with a cage according to an embodiment of the present invention, and FIG. 1B is a partially cutaway front view thereof.

FIG. 2 is a partial perspective view of the cage in the roller with the cage.

3A is an enlarged cross-sectional view of a portion serving as a roller guide portion of a pillar portion, and FIG. 3B is a partially broken front view of a modified example of a roller with a cage.

FIG. 4 is a partially omitted cutaway side view of another embodiment of the present invention.

FIG. 5 is a partially omitted cutaway side view of still another embodiment of the present invention.

FIG. 6 is a schematic diagram of a planetary gear reduction device using the roller with the cage.

FIG. 7 is a partially cutaway side view of the planetary gear reduction device.

8A is a partially broken front view of a conventional roller with a cage, and FIG. 8B is a partially broken side view thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cage 2 ... Roller 3 ... Pocket 4 ... Column part 4a ... Thin part 4b ... Roller guide part 4ba ... Pocket opening edge side 4bb ... Surface pressing part 5 ... Inner peripheral groove 6 ... Projection 7 ... Outer peripheral groove 8 ... Flange part D1 … Inner diameter of roller guide PCD… Pitch circle diameter

Claims (7)

[Claims] 1. A cage comprising a cage and a plurality of rollers, wherein the cage has a cylindrical shape, and pockets are formed at a plurality of positions in a circumferential direction. It is formed thin by an inner circumferential groove having a diameter larger than the pitch circle diameter of the pitch circle, and a protrusion for preventing the roller from coming off outward is formed on the thin portion, and both sides of the thin portion in the pillar portion are formed. A roller with a retainer, which is a roller guide portion and the inner diameter of each roller guide portion is slightly larger than the pitch circle diameter. 2. The roller diameter is dw, the number of rollers is n, the pitch circle diameter of the roller array is PCD, and when (dw × n) / (π × PCD) ≧ 0.8, the inner diameter of the roller guide is The roller with a retainer according to claim 1, wherein the roller pitch diameter is larger than the roller pitch circle diameter. 3. The roller with a retainer according to claim 1, wherein an annular outer peripheral groove is formed at a central portion in the axial direction of the thin portion. 4. A thin portion of the pillar portion and a length portion serving as a roller guide portion on both sides of the thin portion are such that the pocket opening edge side of the outer diameter side has a pitch circle larger than the outer diameter surface position of the retainer annular portion. The roller with a retainer according to any one of claims 1 to 3, which is located on a side of the cage. 5. The roller guide portion and the thin portion have a thickness of 3
The roller with a retainer according to any one of claims 1 to 4, wherein a surface pressing portion having an inclination angle of 0 to 100 is formed. 6. The gap between the thin portion of the pillar portion and the outer diameter surface and the gap between the roller guide portions on both sides of the thin portion and the outer diameter surface are substantially equal to each other. Rollers with retainers as described in any of them. 7. A retainer and a plurality of rollers, wherein the retainer has a cylindrical cross-sectional shape having flanges extending inwardly at both ends in an axial direction, and a plurality of rollers in a circumferential direction. A pocket is formed in the place, and the axial center part of the pillar between the pockets is formed thin by an inner circumferential groove having a diameter larger than the pitch circle diameter of the roller arrangement, and the thin part, outward of the roller A retainer in which protrusions are formed to prevent the thin portion from being pulled out, and both side portions of the thin portion in the pillar portion serve as roller guide portions, and the inner diameter of both roller guide portions is slightly larger than the pitch circle diameter. Around time.