JP5162897B2 - Bearing device with pulley - Google Patents

Description

  The present invention relates to a bearing device with a pulley that is suitable for an idler bearing, a tensioner bearing, and the like that are used for adjusting the tension of a belt and changing a traveling path in, for example, a timing belt of an automobile and an accessory driving belt.

  Conventionally, a metal outer ring of a rolling bearing has been used as a bearing used in a drive system for transmitting rotational power of an engine to an auxiliary machine of an automobile via an auxiliary machine drive belt or the like in order to reduce its weight and cost. In some cases, a pulley-equipped bearing device in which a synthetic resin pulley is integrally formed on the outer peripheral surface of the pulley is used.

  FIG. 4 is a cross-sectional view of a conventional bearing device with a pulley. The bearing device with a pulley includes a ball bearing 10 having an outer ring 11, an inner ring 12, and a ball 13 disposed between the two rings, and a resin pulley 20 ′ attached to the outer ring 11.

  Here, when the pulley 20 ′ is formed by insert molding using nylon or the like on the outer periphery of the outer ring 11, the bearing material (steel material) is used when used in a high temperature environment such as an engine room. There is a risk that creep (slip) will occur in the pulley 20 ′ due to the difference in linear expansion coefficient between the resin and the resin, making continuous use difficult.

Therefore, in the bearing device with a pulley shown in FIG. 4, a peripheral groove 11a is provided on the outer periphery of the outer ring 11, and the resin is poured into the peripheral groove 11a and solidified to suppress separation between the outer ring 11 and the pulley 20 '. Like to do. However, if such a circumferential groove 11a must be formed in the outer ring 11, an inexpensive general-purpose bearing cannot be used, resulting in an increase in cost.
JP 2002-266990 A

  On the other hand, Patent Document 1 discloses an example in which a resin pulley is formed on an outer ring of a ball bearing by insert molding. According to the technique of Patent Document 1, since the resin is formed so as to go around from the outer periphery of the outer ring to both ends in the axial direction, there is little possibility of dropping from the ball bearing even if creep occurs in the resin pulley. However, when a resin pulley is insert-molded into the outer ring of a ball bearing, since it is performed after the outer ring has been processed, care must be taken so that scratches or the like do not occur on the precisely processed raceway surface. May take time.

  The present invention has been made in view of the problems of the prior art, and an object thereof is to provide a pulley-equipped bearing device that can be easily assembled and handled.

The pulley bearing device of the present invention is
A ball bearing having an outer ring, an inner ring, a rolling element disposed between the two rings, a cage that holds the rolling element, and a seal that seals between both wheels on both axial sides of the rolling element;
In a bearing device with a pulley comprising a pulley attached to the outer ring,
The pulley has a metal attachment member that fits into the outer ring, and a resin hollow annular pulley body fixed to the attachment member,
The mounting member includes a hollow cylindrical portion having rectangular openings arranged at equal intervals in the circumferential direction on the outer periphery, and extends radially inward from the one end of the hollow cylindrical portion to the vicinity of the outer peripheral surface of the inner ring. standing, and a flange portion having a suppressing shielding function damage of the seal due to foreign matter scattered, which is integrally formed a metal plate by pressing,
The pulley main body is insert-molded on the outer periphery of the attachment member, and the inner peripheral side of the pulley main body is solidified by the resin melted at the time of molding entering the opening, and the flange portion and the It is solidified to go around the side of the hollow cylindrical part and sandwich it in the axial direction,
The hollow cylindrical portion is press-fitted into the outer ring so that the flange portion is in contact with the end surface of the outer ring,
The pulley main body that wraps around the side surface of the hollow cylindrical portion is in contact with the outer periphery of the end of the ball bearing opposite to the flange portion, and does not hinder press-fitting of the hollow cylindrical portion and the outer ring. As described above, the outer ring does not wrap around to the smaller diameter side than the outer shape .

  According to the present invention, the pulley has a metal attachment member that fits into the outer ring and a pulley body fixed to the attachment member. Therefore, after the pulley body is insert-molded into the attachment member, etc. The outer ring only needs to be fitted and attached by press fitting or the like, so that it is easy to handle and there is little risk of damaging the outer ring.

  Incidentally, in the case of the conventional example shown in FIG. 4, the ball bearing is a bearing with a seal. However, in order to avoid, for example, pebbles scattered from the road surface coming into contact with the seal, the cover member 40 is provided separately. . Therefore, the number of parts increases, and the labor and cost of assembling increase.

  On the other hand, if the attachment member made of metal has a flange-like dust seal portion extending radially inward from the outer ring side, the dust seal portion also has a cover member function. Therefore, the number of parts is reduced, and the labor and cost of assembly are reduced.

  It is preferable that the attachment member is easily and surely assembled when it is press-fitted into the outer ring.

  The attachment member forms an opening, and it is preferable that the pulley main body is fitted in the opening because the pulley main body can be prevented from coming off from the attachment member.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a bearing device with a pulley according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a part of an internal combustion engine in which a pulley-equipped bearing device according to the present embodiment is incorporated. FIG. 2 is a cross-sectional view of the pulley bearing device according to the present embodiment. FIG. 3 is a perspective view of the attachment member.

  In FIG. 1, a crank gear 101a is attached to an end portion of a crankshaft 101 that is rotatably arranged with respect to an internal combustion engine (not shown). In parallel with the crankshaft 101, camshafts 102 and 103 are rotatably arranged. Cam gears 102a and 103a are attached to end portions of the camshafts 102 and 103, respectively. A toothed belt 105 is arranged so as to be spanned over the crank gear 101a, the cam gears 102a and 103a, and the water pump pulley gear 104. The back surface of the toothed belt 105 is pressed by a spring (not shown) via two pulley bearing devices 106 and 106 which are idler pulleys, thereby applying a predetermined tension.

  When the crankshaft 101 is rotated via the connecting rod 108 by the explosive force applied to the piston 107, the toothed belt 105 is driven via the crank gear 101a, whereby the water pump is driven via the water pump pulley gear 104. The camshafts 102 and 103 are rotationally driven via the cam gears 102a and 103a, and the valve 109 is reciprocated by the cams 102b and 103b formed around the camshafts 102a and 103a. At this time, the bearing devices 106 and 106 with pulleys have a function of moving outward as the tension increases while contacting the moving toothed belt 105 and maintaining the tension substantially constant. Hereinafter, the bearing device 106 with a pulley will be described. However, since the two bearing devices with a pulley have the same configuration, only one of them will be described.

  In FIG. 2, the bearing device 106 with a pulley includes an outer ring 11, an inner ring 12, a ball 13 that is a rolling element disposed between both wheels, a cage (not shown) that holds the ball 13, and an axis of the ball 13. It consists of a ball bearing 10 having seals 14 and 15 for sealing between both wheels on both sides in the direction, and a pulley 20 attached to the outer ring 11. The pulley 20 includes a metal attachment member 21 that is fitted to the outer ring 11 and a pulley body 22 that is fixed to the attachment member 21. A toothed belt 105 (FIG. 1) comes into contact with the outer periphery of the pulley body 22.

  More specifically, as shown in FIG. 3, the attachment member 21 has a hollow cylindrical portion 21a and a flange portion 21b extending radially inward from one end of the hollow cylindrical portion 21a, and is made of a metal plate. Are formed integrally. On the outer periphery of the hollow cylindrical portion 21a, rectangular openings 21c are formed at equal intervals in the circumferential direction.

  In FIG. 2, a hollow annular pulley body 22 is insert-molded on the outer periphery of the attachment member 21, and the inner peripheral side of the resin melted at the time of molding penetrates into the opening 21c and solidifies, that is, is inserted (A Thus, separation from the attachment member 21 is suppressed. In addition, since a part of the molten resin on the inner peripheral side turns to the outside of the flange portion 21b and is solidified at the time of molding (B), this suppresses separation between the pulley body 22 and the mounting member 21. It is like that.

  When the bearing device with pulley 106 is assembled, the hollow cylindrical portion 21 a of the mounting member 21 is press-fitted into the outer ring 11 of the ball bearing 10 so that the flange portion 21 b abuts on the end surface of the outer ring 11. Further, a spacer 30 is fitted to the inner periphery of the inner ring 12 and is attached to a holder (not shown) (movable with respect to the cylinder block) with a bolt 31.

  According to the present embodiment, since the resin pulley body 22 is insert-molded with respect to the mounting member 21 made of metal, the occurrence of creep is suppressed even in a high temperature environment, and the pulley-equipped bearing device 106 is provided. Can improve the reliability. Further, since the mounting member 21 is press-fitted into the outer ring 11 of the ball bearing 10, the handleability is excellent as compared with the case where insert molding is directly performed on the outer ring 11. Since the pulley body 22 is made of resin, it easily expands / shrinks in response to environmental temperature changes. For example, when used in a high temperature environment, the pulley body 22 expands if the attachment member 21 is too thin. There is also a possibility that the resin inserted in the opening 21c may come out at room temperature. Therefore, for example, when it is known in advance that it will be used in a high temperature environment, by combining the thick attachment member 21, it is possible to ensure a sufficient insertion allowance for the resin even when the pulley body 22 expands. It is preferable.

  Furthermore, since the mounting member 21 made of metal has a flange portion (flange-shaped dust seal portion) 21b extending radially inward from the outer ring 11 side of the ball bearing 10, foreign matter scattered is prevented. It is possible to suppress damage to the seal 14 of the ball bearing 10, thereby having a shielding function, so that it is not necessary to provide a separate cover member, the number of parts is reduced, and labor and cost for assembly are reduced. .

  As described above, the present invention has been described in detail with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be appropriately changed and improved without departing from the spirit thereof. Of course there is. The pulley-equipped bearing device of the present invention is not limited to use in a drive system of auxiliary machinery for an internal combustion engine, and is also used in various industrial machines.

It is a perspective view which shows a part of internal combustion engine incorporating the bearing apparatus with a pulley concerning this Embodiment. It is sectional drawing of the bearing apparatus with a pulley concerning this Embodiment. It is a perspective view of an attachment member. It is sectional drawing of the bearing apparatus with a pulley which is a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Ball bearing 11 Outer ring 11a Circumferential groove 12 Inner ring 13 Ball 14, 15 Seal 20 Pulley 21 Mounting member 21a Hollow cylindrical part 21b Flange part 21c Opening 22 Pulley main body 30 Spacer 31 Bolt 40 Cover member 101 Crankshaft 101a Crank gear 102, 103 Camshaft 102a, 103a Cam gear 102b, 103b Cam 104 Water pump pulley gear 105 Toothed belt 106 Pulley bearing device 107 Piston 108 Connecting rod 109 Valve

Claims (2)

A ball bearing having an outer ring, an inner ring, a rolling element disposed between the two rings, a cage that holds the rolling element, and a seal that seals between both wheels on both axial sides of the rolling element;
In a bearing device with a pulley comprising a pulley attached to the outer ring,
The pulley has a metal attachment member that fits into the outer ring, and a resin hollow annular pulley body fixed to the attachment member,
The mounting member includes a hollow cylindrical portion having rectangular openings arranged at equal intervals in the circumferential direction on the outer periphery, and extends radially inward from the one end of the hollow cylindrical portion to the vicinity of the outer peripheral surface of the inner ring. standing, and a flange portion having a suppressing shielding function damage of the seal due to foreign matter scattered, which is integrally formed a metal plate by pressing,
The pulley main body is insert-molded on the outer periphery of the attachment member, and the inner peripheral side of the pulley main body is solidified by the resin melted at the time of molding entering the opening, and the flange portion and the It is solidified to go around the side of the hollow cylindrical part and sandwich it in the axial direction,
The hollow cylindrical portion is press-fitted into the outer ring so that the flange portion is in contact with the end surface of the outer ring,
The pulley main body that wraps around the side surface of the hollow cylindrical portion is in contact with the outer periphery of the end of the ball bearing opposite to the flange portion, and does not hinder press-fitting of the hollow cylindrical portion and the outer ring. The pulley-equipped bearing device according to claim 1, wherein the bearing device does not go around to a smaller diameter side than an outer shape of the outer ring .   2. The bearing device with a pulley according to claim 1, wherein a part of the pulley main body fitted into the opening is in contact with an outer ring of the ball bearing.

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