JP2018071720A - Corrugated holder and ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a corrugated holder capable of reducing friction loss between itself and a ball, and a ball bearing including the corrugated holder.SOLUTION: A corrugated holder is configured such that a pair of annular members includes a plurality of concave pocket parts for holding a ball, and a flat plate part connecting between the pocket parts, wherein the pocket parts and the flat plate parts are alternately formed in a circumferential direction; and the flat plates are connected to each other in a state where the concave pocket parts are opposite to each other. In the concave pocket part, formed is a plurality of open holes disposed through a connection part extending in a radial direction of the holder.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a corrugated cage and a ball bearing including the corrugated cage, and more particularly to a corrugated cage suitable for automobile transmission and a ball bearing including the corrugated cage.

  The transmission mounted on the automobile is provided for shifting the rotation of the engine and transmitting it to the drive wheels in order to drive the automobile in accordance with the speed desired by the driver. As one type of transmission, a dual clutch transmission (DCT) having two clutches is known.

  FIG. 5 is a diagram showing a configuration of a dual clutch transmission (hereinafter also referred to as “DCT”) disclosed in Patent Document 1. The rotational power of the engine 104 is transmitted to the first input shaft 121 and the second input shaft 122 via the first clutch disk 141 and the second clutch disk 142 constituting the dual clutch, respectively. A plurality of gears 151, 153, 155, and 157 with different numbers of teeth are fixed to the first input shaft 121, and a plurality of gears 152, 154, and 156 are fixed to the second input shaft 122.

The first countershaft 131 is provided with gears 161 and 163 that can mesh with a gear fixed to the first input shaft 121, and gears 164 and 170 that can mesh with a gear fixed to the second input shaft 121, The second counter shaft 132 is provided with gears 162 and 166 that can mesh with a gear fixed to the second input shaft 122 and gears 165 and 167 that can mesh with a gear fixed to the first input shaft 121. Yes. Since the final reduction gear 158 attached to the first countershaft 131 and the final reduction gear 168 attached to the second countershaft 132 are always meshed with the ring gear 180, the rotational power of the engine 104 is increased. The ring gear 180 is finally transmitted to drive wheels (not shown). This detects the driver's accelerator depressing speed, etc., selects the optimum clutch and gear, and enables traveling at a desired speed.

Incidentally, in the DCT, as is apparent from FIG. 5, at least concentric input shafts 121 and 122, a first counter shaft 131, and a second counter shaft 132 are required, and these three shafts are rotatably supported by the vehicle body. As shown in the drawing, at least six bearings are required for the purpose.

This is the case with an automatic transmission (AT) in which a planetary gear train, a friction plate, etc. are arranged around one shaft to change the speed, and two input shafts and output shafts with different numbers of teeth. Compared to the case of manual transmission (MT: Manual Transmission) in which gears of different stages are arranged to change gears, the number of bearings supporting the shafts is increased by the number of shafts. As the number of bearings increases, friction loss at the bearing portion increases.

In recent years, as a response to global environmental problems, in order to achieve fuel savings in automobiles, there has been an increasing demand for lower torque for transmission bearings. To achieve this lower torque, There is a need for efforts to reduce friction losses in the bearing portion.

FIG. 6 shows an example of a deep groove ball bearing described in Patent Document 2. The deep groove ball bearing 201 includes an inner ring 202, an outer ring 203, a ball 204 as a rolling element, and a cage 205 for holding the ball 204 at a predetermined interval in the circumferential direction. The cage 205 includes a pair of annular members 205a and 205a each having a flat portion 205c and a concave pocket portion 205b, and rivets 206 are caulked to the flat portions 205c and 205c with the pocket portions 205b and 205b facing each other. It is the waveform holder formed by giving. Each annular member 205a is obtained by press-forming a thin steel plate.

This deep groove ball bearing is capable of reducing friction loss in that it is a rolling bearing relative to a sliding bearing. For roller bearings, the friction loss can be reduced due to the small contact area between the ball as the rolling element and the inner ring and outer ring as the races. In this case, the torque of the bearing can be reduced.

JP2013-63719A JP 2008-15610 A

  However, in the deep groove ball bearing 201 shown in FIG. 6, the cage 205 that holds the ball 204 is held in such a manner that the pockets 205 b and 205 b of the pair of annular members 205 a and 205 a wrap the ball 204. As a result, the contact area between each annular member 205a and the ball 204 is increased, which leads to friction loss. For this reason, in order to reduce the weight by reducing the size of the engine or the like and to realize a reduction in fuel consumption as much as possible, it is desired that the friction loss between the cage and the ball can be reduced as much as possible.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a corrugated cage capable of reducing a friction loss between the corrugated cage and the ball, and a ball bearing provided with the corrugated cage. There is to do.

The above object of the present invention can be achieved by the following constitution.
(1) A plurality of concave pocket portions for holding balls and flat plate portions connecting the pocket portions are provided, and the pocket portions and the flat plate portions are alternately formed in the circumferential direction. A pair of annular members are corrugated cages that combine the flat plate portions with the concave pocket portions facing each other,
The corrugated cage in which the concave pocket portion is formed with a plurality of through-holes arranged via a connecting portion extending in the radial direction of the cage.
(2) The corrugated cage according to (1), wherein at least a peripheral portion of the through hole in the circumferential direction side is chamfered.
(3) An inner ring having an inner ring raceway surface on an outer peripheral surface, an outer ring having an outer ring raceway surface on an inner peripheral surface, and a plurality of balls arranged to be freely rollable between the outer ring raceway surface and the inner ring raceway surface; A ball bearing that holds the plurality of balls in the circumferential direction at substantially equal intervals,
A ball bearing, wherein the corrugated cage is the corrugated cage according to (1) or (2).

  According to the present invention, the pocket portions of the pair of annular members are formed with a plurality of through holes that are divided from each other by the connecting portion extending in the radial direction of the cage. The contact area is reduced by the amount of the plurality of through holes, and friction loss due to frictional contact can be reduced.

It is an expanded sectional view explaining the ball bearing by which 1st Embodiment of the waveform holder which concerns on this invention was employ | adopted. It is a perspective view of the waveform holder shown in FIG. It is the perspective view which looked at the annular member of the waveform holder shown in Drawing 2 from the inside of the pocket part. It is sectional drawing of 2nd Embodiment of the waveform holder which concerns on this invention. It is a skeleton figure which shows an example of a dual clutch transmission. It is the perspective view which fractured | ruptured a part which shows an example of a deep groove ball bearing.

Embodiments of the present invention will be described below with reference to the drawings as appropriate.
(First embodiment)

  1 to 3 show a first embodiment. As shown in FIG. 1, a ball bearing 1 according to this embodiment includes an inner ring 2 having an inner ring raceway 2a on an outer peripheral surface and an outer ring 3 having an outer ring raceway 3a on an inner peripheral surface. And a plurality of balls 4 that are provided between the inner ring raceway 2a and the outer ring raceway 3a so as to be freely rollable, and a cage 5 that holds the balls 4 in a freely rollable manner.

  The inner ring 2 is preferably made of bearing steel (for example, SUJ2), and an inner ring raceway groove 2a is formed on the outer peripheral surface. The inner peripheral surface has a cylindrical shape and is attached to the shaft 11.

  The outer ring 3 is preferably made of bearing steel (for example, SUJ2), and an outer ring raceway groove 3a facing the inner ring raceway groove 2a is formed on the inner peripheral surface. The outer peripheral surface of the outer ring is fixed to the housing 12.

  The balls 4 as rolling elements are preferably made of bearing steel (for example, SUJ2), and are disposed between the inner ring raceway groove 2a and the outer ring raceway groove 3a so as to be able to roll.

  The retainer 5 is called a corrugated retainer, and is formed by joining a pair of annular members 5 a and 5 a with a plurality of rivets 6 as shown in FIG. 2.

  The two annular members 5a and 5a are formed into a corrugated annular shape by punching and bending a metal plate material such as a steel plate and a stainless steel plate. Such an annular member 5a includes a partially spherical shell-shaped concave pocket portion 5b and a flat plate portion 5c connecting adjacent pocket portions 5b and 5b, and the pocket portion 5b and the flat plate portion 5c are connected to each other. Are alternately formed in the circumferential direction.

Further, as shown in detail in FIG. 3, the central portion of the pocket portion 5b is disposed via a connecting portion 5d extending in the radial direction of the cage 5 (the direction crossing the pocket portion 5b in the width direction). A plurality of through holes 5e are formed. In the present embodiment, the number of connecting portions 5d is one and the number of through holes 5e is two. However, by providing a plurality of connecting portions, the number of connecting holes may be one plus one connecting portion.

  The rivet 6 is made of a metal such as steel or stainless steel, and sandwiches the flat plate portions 5c and 5c between the head portion 6a and the crimped portion (invisible in the back side of the annular member 5a in FIG. 2). Thus, the pair of annular members 5a and 5a are connected to each other.

  Next, the operation of this embodiment will be described.

  The ball bearing 1 is used for supporting an input shaft, a first counter shaft, and a second counter shaft in a DCT as shown in FIG. 5, for example. When the rotational force from the engine is transmitted to the drive wheels via the transmission, the inner ring 2 rotates with the rotation of the shaft 11 (FIG. 1). By this rotation of the inner ring, the balls 4 that are in contact with the inner ring 2 and the cage 5 that holds the balls 4 also rotate around the shaft 11.

At this time, since the through hole 5e (FIGS. 2 and 3) is formed in the cage 5 of the present embodiment, the contact area between the balls 4 and the cage 5 is reduced, and the friction loss during rotation of the bearing is reduced. Can be reduced. Moreover, by forming the through hole 5e, the weight of the cage 5 itself is reduced, leading to fuel saving. Furthermore, the through hole 5e is provided with a connecting portion 5d extending in the radial direction of the cage 5, so that the strength of the cage can be secured.

  As described above, according to the ball bearing 1 of the present embodiment, the pocket portions 5b and 5b of the pair of annular members 5a and 5a are arranged via the connecting portions 5d extending in the radial direction of the cage 5. Since the plurality of through holes 5e are formed, the contact area between the cage 5 and the balls 4 is reduced by the amount of the plurality of through holes 5e, and friction loss due to frictional contact can be reduced.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG. In addition, about the structure same or similar to 1st Embodiment, the same or similar code | symbol is attached | subjected and detailed description is abbreviate | omitted. FIG. 4 is a cross-sectional view of the cage 25 as viewed from the outer diameter side of the bearing. The difference from the first embodiment is that at least a circumferential edge 25f of the annular member 25a of the through hole 25e is smoothly rounded with a chamfer.

By such chamfering, the flow of the lubricating oil passing through the through hole 25e becomes smooth, and the lubrication state in the bearing can be kept good. The chamfering process may be a C chamfering process. Further, the chamfering process may be performed on the entire circumference of the through hole 25e including the radial side edge of the cage 25.

  In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably. For example, the example in which the ball bearing is used to support the shaft of the DCT has been described. However, the ball bearing may be used to support the shaft of the MT or AT, and supports the rotating shaft of the motor, for example. May be used to Furthermore, it is not limited to the case of inner ring rotation, and may be used for outer ring rotation.

DESCRIPTION OF SYMBOLS 1 Ball bearing 2 Inner ring 3 Outer ring 4 Ball 5, 25 Corrugated cage 5a, 25a Annular member 5b, 25b Pocket part 5c, 25c Flat plate part 5d, 25d Connection part 5e, 25e Through hole 25f Peripheral part

Claims (3)

A pair of annular portions each having a plurality of concave pocket portions for holding balls and flat plate portions connecting the pocket portions, wherein the pocket portions and the flat plate portions are alternately formed in the circumferential direction. A corrugated holder that joins the flat plate parts to each other in a state where the concave pocket parts face each other,
The corrugated cage in which the concave pocket portion is formed with a plurality of through-holes arranged via a connecting portion extending in the radial direction of the cage.   The corrugated cage according to claim 1, wherein at least a peripheral edge portion of the through hole on a circumferential side of the cage is chamfered. An inner ring having an inner ring raceway surface on an outer peripheral surface, an outer ring having an outer ring raceway surface on an inner peripheral surface, a plurality of balls arranged to roll between the outer ring raceway surface and the inner ring raceway surface, and the plurality A ball bearing comprising: a corrugated cage that holds the balls in the circumferential direction at substantially equal intervals,
A ball bearing, wherein the corrugated cage is the corrugated cage according to claim 1.

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