JP2000179544A - Needle roller having holder, and reduction gear using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a needle roller having a holder capable of obtaining a large load capacity in a limited space, excellent in the roller guide function, the strength and the accuracy, and free from any troubles when the holder is brought into slidable contact with adjacent parts such as a planetary gear on a crank shaft. SOLUTION: A needle roller having a holder is provided a holder 1 comprising an external member 3 and an internal member 4, and a roller 2. The external member 3 is provided with an annular part 3a whose diameter is larger than a pitch circle diameter PCD of the roller array, and a flange part 3b both end parts of which are folded inwardly. The internal member 4 is formed annular and smaller in diameter than the pitch circle diameter PCD of the roller array. Pockets 5, 6 are provided in the external and internal members 3, 4 to accommodate the roller 2. The flange part 3b may be provided on the internal member 4 instead of the external member 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a needle roller with a retainer for obtaining a maximum load capacity in a certain space, and a planetary gear reduction device using the same.

[0002]

2. Description of the Related Art There is a full-roller type as a bearing for obtaining the maximum load capacity within a certain space. However, there is a problem in handling, that is, poor handling during assembly and disassembly. Functional problems due to roller skew are inherent. In order to solve these problems, various needle rollers with retainers have been proposed. In order to hold the rollers, the retainer needs to prevent the rollers from falling out and the rollers from stopping inward.

FIG. 7 shows an example of the cage.
The retainer 70 shown in the figure has a M-shaped cross section, a central annular portion 71 smaller in diameter than the roller pitch diameter PCD, and a roller pitch diameter P.
The outer annular portion 72 has a diameter larger than that of the CD, and the flange portions 73 are bent from the outer annular portion 72 toward the inner diameter side. In this retainer 70, the rollers 74 are prevented from falling out by the outer annular portion 72, and the rollers 74 are prevented from falling out by the central annular portion 71. That is, the pockets 75 for accommodating the rollers 74 are formed at equal circumferential positions of the annular portions 71 and 72, and the width of the locking pieces 76 protruding from the pockets 75 is determined by the outer diameter of the rollers 74. Is also slightly smaller. The roller 74 is mounted from the outer diameter side of the locking piece 7 of the pocket 75.
6 is elastically deformed.

[0004]

As the number of rollers 74 incorporated in the retainer 70 is increased within a certain space (a certain inner diameter and an outer diameter), the column width dimension a in FIG. This not only limits the processing but also reduces the strength of the cage. Therefore, the retainer 70 as shown in FIG.
In this case, a cage having a basically different configuration is required. Further, in a needle roller with a retainer interposed between a planetary gear and a crankshaft in a planetary gear reduction device, there is a demand for a flange area of the retainer. That is, in the case where two planetary gears are arranged side by side on the eccentric shaft portion adjacent to the crankshaft, the flange portion of the cage slides on the width surface of the adjacent planetary gear as the eccentric shaft portions rotate eccentrically. Therefore, if the area of the flange portion is not enough, it may interfere with the inner diameter of the adjacent planetary gear.

An object of the present invention is to obtain a large load capacity in a certain space, to be excellent in a roller guide function, strength and accuracy, and to have no problem even when the cage slides against an adjacent part. It is to provide a needle roller with a retainer. Another object of the present invention is to facilitate formation of a roller guide surface and improve productivity. Still another object of the present invention is to provide a needle roller with a retainer interposed between a planetary gear and a crankshaft without causing a problem of interfering with an inner diameter of an adjacent planetary gear, and also having a roller guide function, a strength surface, and an accuracy surface. However, it is an object of the present invention to provide a planetary gear reduction device which is excellent and can obtain a large load capacity in a certain space, and can make the entire device compact.

[0006]

SUMMARY OF THE INVENTION The present invention is based on a needle roller with a retainer comprising a retainer and a retainer, wherein the retainer is formed of two parts, an outer member and an inner member. In addition, it has the following features. In the needle roller with the retainer according to the first aspect of the invention, the outer member has an annular portion having a diameter larger than the pitch circle diameter of the roller array, and a flange portion having both ends in the axial direction of the annular portion bent toward the inner diameter side. And The inner member is formed in an annular shape having a smaller diameter than the pitch circle diameter of the rollers. Pockets are provided at a plurality of locations in the circumferential direction of the annular member and the inner member of the outer member, and the rollers are accommodated over the pockets of the outer member and the inner member. In the needle roller with the retainer according to the second aspect of the invention, the outer member is formed in an annular shape having a diameter larger than the pitch circle diameter of the roller array. The inner member has an annular portion having a diameter smaller than the pitch circle diameter of the rollers, and a flange portion having both ends in the axial direction of the annular portion bent outward. Pockets are provided at a plurality of circumferential positions of the annular portion of the outer member and the inner member, and the rollers are accommodated over the pockets of the outer member and the inner member.

The first and second aspects of the present invention provide
In any case, since the retainer is made up of two parts, an outer member and an inner member, it is possible for the outer member and the inner member to share the function of preventing the roller from falling out and the roller from moving inward. The function of each member can be simplified. For this reason, the shapes of the outer member and the inner member are simplified, manufacturing is facilitated, and it is possible to increase the processing limit of how narrow the column portion between the pockets can be.
As a result, the number of rollers can be increased as much as possible in a fixed space, and the load capacity can be maximized.
In addition, since the shapes of the outer member and the inner member are simplified as described above, the roller guide function is also improved, and the strength is reduced.
Excellent in accuracy. In particular, when the strength of the pillars of the inner member where the width of the pillars is strict is reduced, the thickness of the inner member can be made thicker than that of the outer member.
The degree of freedom of the optimal design increases. In addition, since a flange protruding toward the other member is provided on one of the outer member and the inner member, a certain area can be secured in the flange, and therefore, the retainer is provided with a planetary gear supporting crank. Even in the case where it is installed on a shaft or the like and comes into sliding contact with an adjacent component, trouble such as interference of the retainer with the inner diameter surface of the adjacent component such as the planetary gear is eliminated.

In the present invention, of the outer member and the inner member, the pocket shape of the member without the flange may be a roller guide shape. In this way, by adopting the roller guide shape, the rolling element guide of the cage can be performed. In this case, since the roller guide shape is a member without the flange portion, the flange portion does not hinder the formation of the roller guide shape, and the roller guide shape can be easily formed.

In the present invention, of the outer member and the inner member, the member having no flange may be a member obtained by rounding a band plate and welding both ends. Since the member on the side without flange is a simple annular body, it can be easily processed by using a band plate and the column width can be narrowed, and the number of rollers and roller diameter can be increased even more in a limited space be able to.

In the present invention, of the outer member and the inner member, the member without the flange may be made of a synthetic resin, and the member with the flange may be made of a metal material.
By using a synthetic resin as described above, the shape of the column can be freely designed, for example, the roller guide surface can be formed along the outer diameter of the roller, and the guideability can be improved. Further, since the member made of synthetic resin is a member without the flange, the shape of the pillar portion is not limited for forming the flange portion. further,
Since the member on the side with the flange is made of metal, the strength against sliding contact with the adjacent member can be secured.

[0011] The needle roller with a retainer of each of the above structures of the present invention may be provided between a planetary gear in a planetary gear reduction device and a crankshaft supporting the planetary gear.

[0012] The planetary gear reduction device of the present invention comprises a sun gear having internal teeth or external teeth, a carrier rotatably provided concentrically with the sun gear, and a plurality of rotatably supported adjacent to the carrier. A crankshaft having an eccentric shaft portion,
A planetary gear reduction device comprising: a plurality of planetary gears rotatably mounted on the respective eccentric shaft portions of the crankshaft via needle rollers with retainers and meshing with the sun gear;
The needle roller with the retainer has the following configuration.
The needle roller with the retainer includes a retainer including an outer member and an inner member, and the planetary gear and the crankshaft accommodated in pockets provided at a plurality of circumferential positions of the outer member and the inner member. It consists of a plurality of rollers rolling between the rollers. The outer member and the inner member are each formed of an annular portion having a larger diameter and an annular portion having a smaller diameter than the pitch circle diameter of the roller arrangement, and one of the outer member and the inner member is formed of the annular member. Are provided at both ends in the axial direction with a flange extending radially toward the other member. As described above, the planetary gear reducer in which the planetary gear is installed on the crankshaft,
It is necessary to prevent a needle roller with a retainer interposed between a planetary gear and a crankshaft from interfering with the inner diameter of an adjacent planetary gear. This prevention function can be obtained by the collar of the retainer. Further, in such a planetary gear reduction device, a large load is required to support the planetary gears, and the supporting portion has a limited space, but is divided into the above-described outer member and the inner member. According to the cage, the number of rollers and the diameter of the rollers can be increased in such a limited space, and a large load capacity can be obtained.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A needle roller with a retainer according to a first embodiment of the present invention will be described with reference to FIGS.
This needle roller with a retainer is composed of a retainer 1 and a needle roller 2, and the retainer 1 is composed of an outer member 3 and an inner member 4. The outer member 3 is a roller arrangement pitch circle PCD.
And a flange 3b formed by bending both ends in the axial direction of the annular portion 3a toward the inner diameter side. The inner member 4 is formed in an annular shape having a smaller diameter than the diameter of the pitch circle PCD in the roller arrangement. The annular portion 3a and the inner member 4 of the outer member 3 are cylindrical, and pockets 5 and 6 are provided at a plurality of positions in the circumferential direction at equal intervals. The rollers 2 are accommodated over the pockets 5 and 6 of the outer member 3 and the inner member 4. The portions between the adjacent pockets 5 and between the pockets 6 of the outer member 3 and the inner member 4 become pillars 7 and 8, respectively.

In the outer member 3 on the side with the flange, the width m of the pocket 5 is slightly smaller than the outer diameter Da of the roller 2.
To prevent it from falling out. Inner member 4 without flange
Similarly, the width n of the pocket 6 is formed to be slightly smaller than the outer diameter Da of the roller 2 to prevent the roller 2 from dropping inward. The pocket 6 of the inner member 4 has a roller guide shape. That is, in the pocket 6, the inner surfaces of the pockets on both sides in the circumferential direction are formed on the inclined surface 6a holding the rollers 2. As shown in FIG. 2A, the inclined surface 6a is formed by pressing the pocket 6 by pressing after the punching is performed by pressing or the like as shown in FIG.
Is formed on the inclined surface 6a as shown in FIG. Also, the inner member 4
Is made in an annular shape by rolling a strip such as a steel plate and welding both ends. The pocket 6 is machined before rolling. The outer member 3 is a press-processed product formed by drawing a metal plate such as a steel plate. Further, the outer member 3 is an outer diameter guide.

By configuring the cage 1 as described above, it is possible to accommodate the maximum roller diameter and the maximum number of rollers in a limited space.

FIG. 3 shows a second embodiment. The needle roller with a retainer of this embodiment is the same as the first roller except for the inner member 4A.
Therefore, the same reference numerals are given to the corresponding parts, and the description is omitted. The inner member 4A is formed by injection molding a synthetic resin, and the pocket 6A is formed in a curved surface 8b having an arc-shaped cross section along the outer diameter surface of the roller 2. The pillar portion 8A of the inner member 4A is provided with a protruding portion 8a that protrudes to the outer diameter side from the both side edges in the width direction, and the side surface 8b of the protruding portion 8a has Is formed. Note that not only the protruding portion 8a but also the entire surface of both sides of the pocket 6A
May be formed into a curved surface having an arc-shaped cross-section along the outer diameter surface of.

FIG. 4 shows a third embodiment. The needle roller with a retainer of this embodiment has a configuration in which the outer member 3 and the inner member 4 of the first embodiment are reversed.
The outer member 3B is formed in an annular shape having a diameter larger than the diameter of the pitch circle PCD in the roller arrangement. The inner member 4B includes an annular portion 4Ba having a smaller diameter than the pitch circular diameter PCD of the roller arrangement, and an annular portion 4Ba.
And a flange 4Bb formed by bending both ends in the axial direction of Ba toward the inner diameter side. The annular portions 4Ba of the outer member 3B and the inner member 4B have pockets 5 at a plurality of positions in the circumferential direction at regular intervals.
B and 6B are provided, respectively, and the roller 2 is accommodated in both pockets 5B and 6B. The inner member 4B on the flanged side is an inner diameter guide (guide ring guide), and the outer member 3B on the flangeless side is
The inner surface of the pocket 5B is formed on an inclined surface 5Ba, and is of a rolling element guide type.

FIGS. 5 and 6 show an example of a planetary gear reduction device to which the needle 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. The sun gear 21 is rotatably mounted on each of the eccentric shaft portions 23a and 23b of the crankshaft 23.
Planetary gears 24 and 25 that mesh with the crankshaft 2
3 has a rotation input unit 26 for inputting rotation. The sun gear 21 is fixed to the housing 27, and the carrier 22 is mounted on the housing 27 via a bearing 28 (FIG. 6) so as to be rotatable concentrically with the sun gear 21. The rotation input unit 26 includes 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. 6, the planetary gears 24 and 25 are connected to the crankshaft 2 via needle rollers 31 with retainers, respectively.
3 are mounted on the eccentric shaft portions 23a and 23b. The needle roller with a cage of the present invention, for example, the needle roller with a cage according to any of the first to third embodiments, is used as the needle roller with a holder 31.

The operation of this 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 needle roller 31 with a retainer, and the whirling of the crankshaft 23 is such that the planetary gears 24 and 25 move inside the sun gear 21 having the internal teeth. Synchronizes with the combined motion of revolution and rotation when turning. 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, 2
The inertial forces due to whirling of the planetary gears 24 and 25 cancel each other. The internal gear sun gear 21 is fixed, and the planetary gears 24 and 25 move around the internal circumference 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 needle roller 31 with the retainer interposed between the planetary gears 24 and 25 and the crankshaft 23, and the needle roller 31 with the retainer is also used. Is limited in order to avoid an increase in the size of the entire reduction gear transmission. Also,
The cage of the needle roller 31 with the cage is in sliding contact with the width surfaces of the adjacent planetary gears 24 and 25. However, according to the needle rollers with cages of the above embodiments, a large load capacity can be obtained in a limited space, and the outer member 3
Alternatively, since one of the inner members 4 has the flange portion 3b protruding toward the other member, the planetary gear 24 can be brought into sliding contact with the width surfaces of the adjacent eccentric planetary gears 24 and 25. , 25 do not interfere with each other.

[0021]

According to the needle roller with a retainer of the present invention, the retainer is composed of two independent members, an outer member and an inner member.
The functions of preventing the rollers from falling out and inward are assigned to the respective members, so that manufacturing is easy and the limitations on processing are eased, and within a certain space, the number of rollers and the diameter of the rollers are increased. To obtain the maximum load capacity.
The roller guide function is also improved, and strength and accuracy can be improved. In addition, since the flange portion is provided on one of the outer member and the inner member, even when the retainer slides on the adjacent component, it does not interfere with the inner surface of the adjacent component.
The planetary gear reduction device of the present invention has a configuration in which a needle roller with a retainer is interposed between a planetary gear and a crankshaft, but has no problem that the retainer interferes with the inner diameter of an adjacent planetary gear, and The roller guide function, the strength and the accuracy of the needle roller with the container are excellent, and a large load capacity can be obtained in a certain space, so that the entire device can be made compact.

[Brief description of the drawings]

FIG. 1A is a partially broken side view of a needle roller with a retainer according to a first embodiment of the present invention, and FIG. 1B is a partially broken front view thereof.

FIG. 2 is an explanatory view showing a process of forming a roller guide shape of the cage.

FIG. 3A is a partially cutaway side view of a needle roller with a retainer according to a second embodiment of the present invention, and FIG. 3B is a partially cutaway front view of the same.

FIG. 4A is a partially cutaway side view of a needle roller with a retainer according to a third embodiment of the present invention, and FIG. 4B is a partially cutaway front view of the same.

FIG. 5 is a schematic diagram of a planetary gear reduction device using the needle rollers with the cage.

FIG. 6 is a partially cutaway side view of the planetary gear reduction device.

FIG. 7A is a partial perspective view of a conventional needle roller with a retainer, and FIG. 7B is a partial cross-sectional view of the needle roller with the retainer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cage 2 ... Roller 3, 3B ... Outer member 3a ... Annular part 3b ... Flange part 4, 4A ... Inner member 5, 6 ... Pocket 6a ... Inclined surface 21 ... Sun gear 22 ... Carrier 23 ... Crank shaft 23a , 23b eccentric shaft part 24, 25 planetary gear 26 input part 31 needle roller with retainer PCD pitch circle diameter

Claims (7)

[Claims] 1. A cage comprising an outer member and an inner member, and a roller, wherein the outer member has an annular portion having a diameter larger than a pitch circle diameter of a roller array, and both ends in the axial direction of the annular portion. The inner member is formed in an annular shape having a smaller diameter than the pitch circle diameter of the roller array, and the annular portion of the outer member and the plurality of circumferential members of the inner member are formed. A needle roller with a retainer which has a pocket at a location and accommodates the roller over the pockets of the outer member and the inner member. 2. A retainer comprising an outer member and an inner member, and a roller, wherein the outer member is formed in an annular shape having a diameter larger than a pitch circle diameter of a roller array, and the inner member includes a roller. An annular portion having a diameter smaller than the pitch circle diameter of the array, and a flange portion having both ends in the axial direction of the annular portion bent toward the outer diameter side, the circumferential direction of the annular portion of the outer member and the inner member. Needle rollers with retainers that have pockets at a plurality of locations and accommodate the rollers over pockets of the outer member and the inner member. 3. The retainer according to claim 1, wherein, of the outer member and the inner member, a pocket shape of a member having no flange portion is a roller guide shape. With needle rollers. 4. The holding device according to claim 1, wherein, of the outer member and the inner member, a member having no flange portion is formed by rolling a strip and welding both ends. Needle roller with bowl. 5. The outer member and the inner member, wherein a member without a flange portion is made of synthetic resin, and a member with a flange portion is a metal material. Needle rollers with retainers according to 1. 6. The needle roller with a retainer according to claim 1, which is installed between a planetary gear in a planetary gear reduction device and a crankshaft supporting the planetary gear. 7. A crankshaft having a sun gear having internal teeth or external teeth, a carrier rotatably provided concentrically with the sun gear, and a plurality of eccentric shaft portions rotatably supported by and adjacent to the carrier. And a plurality of planetary gears installed on each of the eccentric shaft portions of the crankshaft via a needle roller with a retainer and meshing with the sun gear, wherein the needle roller with a retainer is provided. And a plurality of cages formed of an outer member and an inner member, and a plurality of rollers which are accommodated in pockets provided at a plurality of circumferential positions of the outer member and the inner member and roll between the planetary gear and the crankshaft. And the outer member and the inner member each include an annular portion having a larger diameter and an annular portion having a smaller diameter than the pitch circle diameter of the roller array, and one of the outer member and the inner member. The members of A planetary gear reduction device having a flange portion extending radially toward the other member at both axial ends of the annular portion.