JP2013024308A - Constant-velocity joint device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain space saving by shortening a total length of boots, and to prevent abnormal wear of the boots.SOLUTION: A large-diameter fixed part 4 is fixed to a position 8b pulled in from an axial center direction terminal portion 8a of a joint outer ring 8 to a shaft body side of the joint outer ring 8 by the total or more of thickness of a C-shaped groove 6, thickness of a first valley portion 3b-1 and thickness of a second valley portion 3b-2. Also, an inner diameter of the first valley portion 3b-1 and an inner diameter of the second valley portion 3b-2 are adjusted, and thereby, when a constant-velocity joint 2 is subjected to bent operation at a maximum operation angle, at a compression side of a bellows part 3, the first valley portion 3b-1 and the second valley portion 3b-2 ride on an outer circumferential surface 8d of the joint outer ring 8.

Description

  The present invention relates to a constant velocity joint device. More specifically, the present invention relates to a constant velocity joint device equipped with a flexible boot for retaining grease or preventing dust.

  For example, as shown in FIG. 5, a conventional constant velocity joint device to which a flexible boot is attached includes an outer member 101 and an inner member 102 housed in a receiving hole provided in the outer member 101. A driving shaft 104 is integrally formed at one end of the member 101 and one end of the shaft main body 105 in the axial direction is coupled to the inner member 102 so as to cover the opening of the accommodation hole between the shaft main body 105 and the outer member 101. A boot 106 for storing the joint portion of the constant velocity joint 103 in a sealed manner is provided. The boot 106 is of a bellows type that can be elastically expanded and contracted, and has an outer member 101 and a shaft main body 105 at both longitudinal ends. The band members 107A and 107B are fitted into the fitting grooves 101a and 105a formed on the outer peripheral surfaces of It is intended to be fixed Te (Patent Document 1). In FIG. 5, reference numeral 108 denotes a driving wheel assembled to the driving shaft portion 104, and the driving wheel 108 is rotatably supported by a knuckle arm 109 supported on the body side via a constant velocity joint 103.

JP-A-10-9248

  However, in the constant velocity joint device of Patent Document 1, when the constant velocity joint 103 is operated and the shaft main body 105 is bent with respect to the outer member 101, the bellows portion (three peaks and three peaks) is formed on the compression side of the boot 106. The valley portion) must be accommodated between the end portion (end surface) of the outer member 101 on the fitting groove 101a side and the band member 107B of the shaft body 105, so that at least the total thickness of the bellows portion ( It is necessary to secure the dimension between the end portion of the outer member 101 and the band member 107B by an amount equivalent to the seven membranes of the boot 106, and the length of the boot 106 is required by that amount, so that the space of the boot 106 is saved. There is a problem that it cannot be achieved. This is considered to be a restriction on the installation of the constant velocity joint device, and therefore it is difficult to say that the versatility is high.

  Further, in the constant velocity joint device of Patent Document 1, as described above, the bellows portion of the boot 106 is held between the end portion of the outer member 101 and the band member 107B, so that the constant velocity joint 103 is bent and operated. The bellows trough 106a near the outer member 101 of the boot 106 (in other words, the immediate vicinity of the outer member 101) is pressed against the end of the outer member 101, and there is a problem that early breakage occurs due to abnormal wear in the bellows trough 106a. is there.

  Accordingly, an object of the present invention is to provide a constant velocity joint device that can save space by shortening the overall length of the boot and can prevent abnormal wear of the boot.

  In order to achieve this object, a constant velocity joint device according to claim 1 includes a constant velocity joint having a joint outer ring and a shaft, and a constant velocity joint having a flexible boot mounted so as to cover a joint portion of the constant velocity joint. The flexible boot includes a bellows portion having a plurality of bellows and valley portions, a large-diameter fixing portion and a small-diameter fixing portion for attaching both ends of the bellows portion to a joint outer ring or a shaft, and a large-diameter fixing portion. A C-shaped groove connected to the large-diameter fixed portion and a first peak rising from the end of the C-shaped groove, and the large-diameter fixed portion is fitted to the joint outer ring and the small-diameter fixed portion. Is fitted to the shaft and fixed to the constant velocity joint, and the large-diameter fixed portion extends from the axial end of the joint outer ring to the thickness of the C-shaped groove and the first peak. The first trough is fixed at a position where it is drawn into the shaft body side of the joint outer ring more than the sum of the thickness of the first trough connected to the part and the thickness of the second trough adjacent to the first trough. The point A1 on the outer peripheral surface of the joint outer ring whose inner diameter has moved to the bellows part side by the sum of the thickness of the C-shaped groove and the thickness of the first valley from the end of the large diameter fixing part on the bellows part side And the unfolded length of the flexible boot membrane from the bellows side end of the large-diameter fixing portion to the center of the valley bottom of the first valley portion from the bellows-side end of the large-diameter fixing portion on the side facing the point A1 The chord length d1 or more at the position C1 where the line connecting the point B1 parallel to the shaft axis when the constant velocity joint is bent at the maximum operating angle and the end surface in the axial direction of the joint outer ring intersect. In addition, the inner diameter of the second valley portion is the same as the thickness of the C-shaped groove from the end of the large-diameter fixed portion on the bellows portion side. The point A2 on the outer peripheral surface of the joint outer ring moved to the bellows side by the sum of the thickness of the valley and the thickness of the second valley and the second valley from the bellows side end of the large-diameter fixed portion The axis of the shaft when the constant velocity joint bends to the maximum operating angle from the end of the bellows side of the large-diameter fixing portion on the side facing the point A2 with the deployment length of the flexible boot membrane up to the center of the valley bottom Is set to be equal to or longer than the chord length d2 of the position C2 at which the line connecting the point B2 parallel to the point B2 and the end face of the joint outer ring in the axial direction end, and the position C1 is viewed from the point A1 and the joint outer ring. In the case of the opposite side across the radial position, the inner diameter of the first trough is set not to be the chord length d1 but to the outer diameter of the joint outer ring, and the bellows portion when the constant velocity joint is bent to the maximum operating angle. The first trough and the second trough join on the compression side It rides on the outer peripheral surface of the outer ring.

  The constant velocity joint apparatus according to claim 3 is a constant velocity joint apparatus having a constant velocity joint having a joint outer ring and a shaft, and a flexible boot mounted so as to cover a joint portion of the constant velocity joint. The flexible boot includes a bellows portion having a plurality of bellows mountain valley portions, a large-diameter fixing portion and a small-diameter fixing portion for attaching both ends of the bellows portion to the joint outer ring or the shaft, and a large-diameter fixing portion and a bellows portion. It has a C-shaped groove connected to the large-diameter fixed portion and a first peak rising from the end of the C-shaped groove, and the large-diameter fixed portion is fitted to the joint outer ring and the small-diameter fixed portion is fitted to the shaft. Fixed to the constant velocity joint, and the large-diameter fixed part rides on the wall thickness of the C-shaped groove and the outer peripheral surface of the joint outer ring from the axial direction end of the joint outer ring. The bellows portion of the large-diameter fixed portion is fixed at a position that is more than the sum of the thickness of the bellows bellows portion and pulled into the shaft body side of the joint outer ring, and the inner diameter of the first valley portion connected to the end of the first peak is Point A1 on the outer peripheral surface of the joint outer ring moved to the bellows side by the sum of the thickness of the C-shaped groove and the thickness of the first valley from the end on the side, and the bellows side end of the large-diameter fixed portion The constant velocity joint bends to the maximum operating angle from the end of the bellows portion side of the large diameter fixing portion on the side facing the point A1 with the developed length of the flexible boot membrane from the center to the center of the bottom of the first valley Is set to be equal to or longer than the chord length d1 of the position C1 where the line segment connecting the point B1 parallel to the shaft center of the shaft intersects with the end surface in the axial direction of the joint outer ring, and the first valley The inner diameter of the adjacent second valley portion is equal to the thickness of the C-shaped groove from the end of the bellows portion side of the large-diameter fixed portion and the first Of the second valley portion from the point A2 on the outer peripheral surface of the joint outer ring moved to the bellows portion side by the total thickness of the wall portion and the wall thickness of the second valley portion and the end portion on the bellows portion side of the large diameter fixing portion. The deployment length of the flexible boot membrane up to the center of the valley bottom is the axis of the shaft when the constant velocity joint bends to the maximum operating angle from the end of the bellows side of the large diameter fixing portion on the side facing the point A2. It is set to the chord length d2 or more at the position C2 where the line segment connecting the point B2 taken in parallel and the end face of the joint outer ring in the axial center direction intersect, and further, the third trough after the second trough Also, when riding on the outer peripheral surface of the joint outer ring, the inner diameter after the third valley is set in the same manner as described above, and then the position C1 is the opposite side across the radial position of the joint outer ring as seen from the point A1. In some cases, the inner diameter of the first valley is not a chord length d1, but a joint When the constant velocity joint is set to be larger than the outer diameter of the outer ring and bends to the maximum operating angle, in addition to the first valley and the second valley on the compression side of the bellows, the valley after the third valley is a joint. It rides on the outer peripheral surface of the outer ring.

  Therefore, according to these constant velocity joint devices, the large-diameter fixed portion is fixed at a position drawn from the axial center end portion of the joint outer ring toward the shaft body side, and the bellows portion is bent when the constant velocity joint is bent to the maximum operating angle. Since at least one bellows valley portion runs on the outer peripheral surface of the joint outer ring on the compression side, the bellows portion on the compression side of the flexible boot is sandwiched between the axial end of the joint outer ring and the small diameter fixing portion. Therefore, it is not necessary to secure the dimensions to be accommodated, and the overall length of the flexible boot can be shortened.

  Further, according to these constant velocity joint devices, the large-diameter fixing portion is fixed at a position drawn from the axial center end portion of the joint outer ring toward the shaft body side, and the bellows portion is bent when the constant velocity joint is bent to the maximum operating angle. Since at least one bellows valley on the compression side of the joint runs on the outer peripheral surface of the joint outer ring, the bellows of the flexible boot close to the joint outer ring (in other words, close to the joint outer ring) at the axial direction end of the joint outer ring. The trough is not pressed and abnormal wear of the bellows trough is prevented.

  According to a second aspect of the present invention, in the constant velocity joint device according to the first aspect, the number of bellows valley portions of the flexible boot is two, three, or four in total.

  The invention according to claim 4 is the constant velocity joint device according to claim 3, wherein the number of bellows valley portions of the flexible boot is four or more in total, and more than half of the four or more bellows valley portions are included. It rides on the outer peripheral surface of the joint outer ring.

  In these cases, more than half of all the bellows valley portions of the flexible boot ride on the outer peripheral surface of the joint outer ring, so that the overall length of the flexible boot can be further shortened.

  According to the constant velocity joint device of the present invention, since the overall length of the flexible boot can be shortened, it becomes possible to save the space of the flexible boot and the constant velocity joint device, thereby reducing the installation space. It becomes possible to improve versatility by flexibly responding to constraints.

  Furthermore, according to the constant velocity joint device of the present invention, abnormal wear of the bellows valley portion of the flexible boot near the joint outer ring (near the joint outer ring) can be prevented. It becomes possible to extend the service life, and in addition, it becomes possible to improve versatility by flexibly responding to restrictions on inspection and maintenance.

It is a figure which shows an example of embodiment of the constant velocity joint apparatus of this invention, and is an axial center direction sectional view in the state where the constant velocity joint is not carrying out bending operation. It is a figure which shows an example of embodiment of the constant velocity joint apparatus of this invention, and is an axial center direction sectional drawing of the state in which the constant velocity joint is bending-actuated and has become the maximum operating angle. It is a figure explaining the interference relationship of the internal diameter of a bellows valley part, and a joint outer ring | wheel. (A) is an axial center direction sectional view of the state where the constant velocity joint is not bending. (B) is a perspective view of a state where the constant velocity joint is bent to a maximum operating angle. It is a figure explaining the method to determine the internal diameter of a bellows valley part based on the interference relationship of the internal diameter of a bellows valley part, and a joint outer ring | wheel. It is an axial center direction sectional view showing the conventional constant velocity joint device.

  Hereinafter, the configuration of the present invention will be described in detail based on an example of an embodiment shown in the drawings.

  1 to 4 show an example of an embodiment of the constant velocity joint device of the present invention. The constant velocity joint device includes a constant velocity joint 2 having a joint outer ring 8 and a shaft 9, and a flexible boot 1 mounted so as to cover a joint portion of the constant velocity joint 2.

  As the constant velocity joint 2 in the present invention, the same one as the conventional one can be used. Since the structure of the constant velocity joint is a well-known technique, the details are omitted here.

  The flexible boot 1 includes a bellows portion 3 having a plurality of bellows valley portions 3b, a large-diameter fixing portion 4 and a small-diameter fixing portion 5 for attaching both ends of the bellows portion 3 to the joint outer ring 8 to the shaft 9, respectively. Between the fixing part 4 and the bellows part 3, there is a C-shaped groove 6 connected to the large-diameter fixing part 4 and a first mountain 7 rising from the end of the C-shaped groove 6, and the large-diameter fixing part 4 is a joint The constant velocity joint 2 is mounted by being fitted to the outer ring 8 and the small diameter fixing portion 5 is fitted to the shaft 9 and fixed by fastening the fastening bands 10A and 10B.

  In the present embodiment, the bellows portion 3 is connected to the first mountain 7 and is provided with a first valley portion 3b-1 and, in turn, toward the small-diameter fixed portion 5, a second valley portion 3b-2 and a third valley portion. There are a total of three bellows valley portions 3b of the portion 3b-3.

  In addition, the material of the flexible boot 1 may be any material as long as it is a material normally used as a boot to be attached to the constant velocity joint device.

  1 to 4 are cross sections in the axial direction of the constant velocity joint device (that is, in the direction of the axial center 8e of the joint outer ring 8 and the axial center 9a of the shaft 9 when the operating angle of the constant velocity joint 2 is zero). For example, the shaft 9 is actually a columnar body, and the large-diameter fixing portion 4 is an annular belt-shaped body. In the following description, unless otherwise specified, the axial cross section shown in FIGS. The shape will be described. In other words, in practice, the shapes appearing in FIGS. 1 to 4 are annularly continuous with the same shape, or gradually between the boot compression side (symbol -com) and the boot extension side (symbol -ext). It is continuous in a ring while changing. Further, with respect to the bellows portion 3, the “mountain” refers to a shape projecting outward in the radial direction of the constant velocity joint device (that is, in a direction perpendicular to the direction of the axis (8e, 9a) and away from the axis). The “valley” refers to a shape protruding inward in the radial direction (that is, a direction approaching the axis in a direction orthogonal to the direction of the axis (8e, 9a)).

  In the constant velocity joint device according to the present embodiment, as shown mainly in FIGS. 3 and 4, the large-diameter fixing portion 4 has the thickness of the C-shaped groove 6 and the thickness of the C-shaped groove 6 from the axial end 8 a of the joint outer ring 8. Fixed to the position 8b (withdrawal amount L0) drawn into the shaft body side of the joint outer ring 8 by the sum of the thickness of the first valley 3b-1 connected to the mountain 7 and the thickness of the second valley 3b-2. In addition, the inner diameter D1 of the first valley portion 3b-1 is such that the thickness of the C-shaped groove 6 from the end portion 4a on the bellows portion 3 side of the large-diameter fixed portion 4 and the thickness of the first valley portion 3b-1. The central position of the valley bottom of the first valley portion 3b-1 from the point A1 on the outer peripheral surface 8d of the joint outer ring 8 moved to the bellows portion 3 side by the total t1 and the end portion 4a on the bellows portion 3 side of the large diameter fixing portion 4 From the end 4a on the bellows part 3 side of the large-diameter fixing part 4 on the side facing the point A1, the development length l1 of the membrane of the flexible boot 1 up to (section L1 in FIG. 3) A line segment connecting the point B1 parallel to the axis 9a ′ of the shaft 9 when the constant velocity joint 2 is bent at the maximum operating angle θ intersects the end surface 8c in the axial direction end portion of the joint outer ring 8. The chord length d1 of the position C1 is set, and the inner diameter D2 of the second valley portion 3b-2 is changed from the end 4a on the bellows portion 3 side of the large diameter fixing portion 4 to the thickness of the C-shaped groove 6 and the first valley. The point A2 on the outer peripheral surface 8d of the joint outer ring 8 and the bellows of the large-diameter fixing part 4 moved to the bellows part 3 side by the total amount t2 of the thickness of the part 3b-1 and the thickness of the second valley part 3b-2. Large-diameter fixing portion on the side facing the point A2 of the unfolded length l2 of the flexible boot 1 from the end 4a on the side of the portion 3 to the center of the bottom of the second valley portion 3b-2 (section L2 in FIG. 3) 4 is parallel to the axis 9a 'of the shaft 9 when the constant velocity joint 2 is bent from the end 4a on the bellows portion 3 side to the maximum operating angle θ. The chord length d2 of the position C2 where the line segment connecting the point B2 and the end surface 8c in the axial direction of the joint outer ring 8 intersect is set, and the position C1 of the joint outer ring 8 is viewed from the point A1. In the case of the opposite side across the radial position O, the inner diameter D1 of the first valley 3b-1 is set not to the chord length d1 but to the outer diameter D0 of the joint outer ring 8, and the constant velocity joint 2 is set to the maximum operating angle θ. The first valley portion 3b-1 and the second valley portion 3b-2 are configured to ride on the outer peripheral surface 8d of the joint outer ring 8 on the compression side (3-com) of the bellows portion 3 when the bending operation is performed. Here, if the inner diameter D1 of the first valley 3b-1 is set to be longer than the chord length d1 or the outer diameter D0, and the inner diameter D2 of the second valley 3b-2 is set to be longer than the chord length d2, the first valley 3b- 1 and the second valley portion 3b-2 ride on the outer peripheral surface 8d of the joint outer ring 8, but considering the reduction in the radial direction, the inner diameter D1 of the first valley portion 3b-1 is preferably as the chord length. The inner diameter D2 of the second valley portion 3b-2 should be approximately equal to the chord length d2, and preferably within 120% of each of the chord length d1, the outer diameter D0, and the chord length d2. Preferably, each is within 110%.

  The operating angle of the constant velocity joint 2 is an angle formed by the direction of the axis 8e of the joint outer ring 8 and the direction of the axis 9a (9a ′) of the shaft 9. Further, the outer peripheral surface 8d of the joint outer ring 8 is a side peripheral surface that is not the axial end portion end surface 8c.

  In the present embodiment, the large-diameter fixing portion 4 is fixed at a position 8b where the end portion 4a on the bellows portion 3 side is retracted from the end portion 8a in the axial direction of the joint outer ring 8 to the shaft body side by the amount of retraction L0. In this embodiment, when the constant velocity joint 2 is bent, the first valley portion 3b-1 and the second valley portion 3b-2 are joints among the three bellows valley portions 3b of the bellows portion 3-com on the boot compression side. It rides on the outer peripheral surface 8d of the outer ring 8 (see FIG. 2), and the thickness of the C-shaped groove 6 (for one boot membrane) and the thickness of the first valley 3b-1 (for two boot membranes). The pull-in amount L0 is set to be slightly larger than the sum of the thickness of the second valley portion 3b-2 (for two boot membranes). The pull-in amount L0 may be at least the sum of the thickness of the C-shaped groove 6 and the thickness of the bellows valley portion 3b that rides on the outer peripheral surface 8d of the joint outer ring 8, and is the same as the sum. Also good.

  The C-shaped groove 6 is provided so as to be connected to the bellows portion 3 side of the large-diameter fixed portion 4 and is formed with the opening portion facing the outside of the joint outer ring 8 (in other words, radially outward of the joint outer ring 8). The The C-shaped groove 6 makes the first mountain 7 easier to deform as the C-shaped groove 6-com on the boot compression side, and the first mountain 7-com becomes the large-diameter fixing portion 4 by contacting both ends of the opening. The C-shaped groove 6-ext on the boot extension side opens to assist the deployment of the flexible boot 1.

  The first mountain 7 is provided so as to rise from the end of the C-shaped groove 6 on the bellows portion 3 side, and is formed in a mountain shape having a vertex protruding toward the outside of the joint outer ring 8, and toward the outside of the joint outer ring 8. It is configured to be bendable. In addition, the 1st mountain 7 is formed so that it may have a gentle inclined surface compared with the trough part and peak part of the bellows part 3, and the expansion-contraction amount is large compared with the valley part and peak part of the bellows part 3 for that. And the inner storage space is large.

  In the present embodiment, the first peak 7 is located on the large-diameter fixed part 4 side of the end face 8c in the axial direction of the joint outer ring 8 when the operating angle of the constant velocity joint 2 is zero. The end portion on the bellows portion 3 side is closer to the small-diameter fixed portion 5 side than the end surface 8c in the axial direction (the first trough portion 3b-1 does not ride on the outer peripheral surface 8d of the joint outer ring 8). It is formed.

  For this reason, when the constant velocity joint 2 is bent, the first crest 7-com on the boot compression side greatly draws the bellows portion 3-com toward the large-diameter fixed portion 4 side and the bellows portion 3b (of the bellows portion 3). The first mountain 7-ext on the boot extension side is the inner surface of the first mountain 7-ext and the end of the joint outer ring 8 in the axial direction. It works to prevent contact with the portion 8a (see FIG. 2). On the boot compression side, the bellows portion 3-com is ridden on the outer peripheral surface 8d of the joint outer ring 8, and on the boot extension side, the axial end portion 8a (and its surroundings) of the joint outer ring 8 is within the first mountain 7-ext. As a result, the entire flexible boot 1 is reduced in size and space saving is realized.

  Due to the configuration of the C-shaped groove 6 and the first peak 7, when the operating angle of the constant velocity joint 2 increases, the first peak 7 -com on the boot compression side that receives the compressive force is directed to the outside of the joint outer ring 8. The C-shaped groove 6-com that receives the compression force is also bent while closing the opening.

  Accordingly, when the operating angle of the constant velocity joint 2 is increased, the joint of the first bellows 7-com on the boot compression side and the bellows valley portion 3b of the bellows portion 3 connected to the first peak 7-com. A plurality of bellows valley portions (the first valley portion 3b-1 and the second valley portion 3b-2 in the example of FIG. 2) near the outer ring 8 or near the joint outer ring 8 can easily ride on the outer peripheral surface 8d of the joint outer ring 8. Become.

  As described above, the pull-in amount L0 is ensured between the axial end 8a of the joint outer ring 8 and the large-diameter fixed part 4, and the bellows valley part 3b near the joint outer ring 8 of the bellows part 3-com on the boot compression side. Is mounted on the outer peripheral surface 8d of the joint outer ring 8, so that it is more flexible than the case where the accommodation space of the bellows portion 3-com on the boot compression side is secured between the end surface 8c in the axial direction and the small diameter fixing portion 5. The overall length of the boot 1 can be shortened. Further, the bellows valley portion 3b near the joint outer ring 8 (closest to the joint outer ring 8) of the bellows portion 3-com on the compression side of the boot may be pressed against the end surface 8c in the axial direction of the joint outer ring 8 to be worn. Is prevented.

  Further, the inner diameter of the bellows valley portion 3b is set as follows in the present embodiment so as not to come into contact with the joint outer ring 8 when the constant velocity joint 2 is bent.

  First, in order to determine the inner diameter D1 of the first valley portion 3b-1, the thickness of the C-shaped groove 6 from the end portion 4a on the bellows portion 3 side of the large-diameter fixing portion 4 of the flexible boot 1 (one boot membrane) And the point A1 on the outer peripheral surface 8d of the joint outer ring 8 moved to the bellows part 3 side by the total amount t1 of the thickness of the first trough part 3b-1 (two boot membranes) and the large-diameter fixing part 4 Large diameter fixing on the side facing the point A1 of the unfolded length l1 of the flexible boot 1 from the end 4a on the bellows portion 3 side to the center of the bottom of the first valley portion 3b-1 (section L1 in FIG. 3) A point B1 parallel to the axis 9a 'of the shaft 9 when the constant velocity joint 2 is bent at the maximum operating angle θ is connected from the end 4a on the bellows part 3 side of the part 4 to the point A1. The chord length d1 of the position C1 where the line segment connecting B1 and the end surface 8c in the axial direction of the joint outer ring 8 intersect is derived.

  Further, in order to determine the inner diameter D2 of the second valley portion 3b-2, the thickness of the C-shaped groove 6 from the end portion 4a on the bellows portion 3 side of the large-diameter fixing portion 4 of the flexible boot 1 (one boot membrane) Joint outer ring moved to the bellows part 3 side by a total amount t2 of the wall thickness of the first valley part 3b-1 (for two boot membranes) and the wall thickness of the second valley part 3b-2 (for two boot membranes) 8 from the point A2 on the outer peripheral surface 8d and the end portion 4a on the bellows portion 3 side of the large-diameter fixing portion 4 to the center of the valley bottom of the second valley portion 3b-2 (section L2 in FIG. 3). The axial center 9a of the shaft 9 when the constant velocity joint 2 is bent to the maximum operating angle θ from the end 4a on the bellows portion 3 side of the large-diameter fixed portion 4 on the side facing the point A2 with the developed length l2 of the film 9 And a line segment connecting the point A2 and the point B2 and the end surface 8c in the axial direction of the joint outer ring 8 intersect with each other. To derive a chord length d2 of the position C2 to be.

  In addition, in the present embodiment, the position C1 at which the line segment connecting the point A1 and the point B1 intersects the axial end portion end surface 8c of the joint outer ring 8 is the radial position O of the joint outer ring 8 as viewed from the point A1. Since it is on the opposite side, the inner diameter D1 of the first valley 3b-1 is set not to the chord length d1 derived as described above but to the outer diameter D0 of the joint outer ring 8. This is because when the intersecting position C1 is on the opposite side across the radial position O, the first trough 3b-1 accommodates the radial position O of the joint outer ring 8, so the first trough 3b- This is because the inner diameter of 1 must be equal to or greater than the outer diameter D0 of the joint outer ring 8.

  On the other hand, the position C2 where the line segment connecting the point A2 and the point B2 intersects the axial end portion end surface 8c of the joint outer ring 8 is closer to the front side than the radial position O of the joint outer ring 8 as viewed from the point A2 (in other words, Therefore, the inner diameter D2 of the second valley 3b-2 is set to the chord length d2 derived as described above.

  In the present embodiment, the third valley portion 3b-3 of the bellows portion 3 is configured not to ride on the outer peripheral surface 8d of the joint outer ring 8. For this reason, the inner diameter D3 of the third valley portion 3b-3 is not limited to the contact with the joint outer ring 8 when the constant velocity joint 2 is bent, and the dimension of the normal boot bellows portion is considered. For example, the dimensions of the adjacent second valley 3b-2, the dimensions of the small-diameter fixed part 5, the folding dimension on the boot compression side (3-com), the extension (deployment) dimension on the boot extension side (3-ext), etc. To be determined.

  According to the constant velocity joint device of the present invention configured as described above, the large-diameter fixing portion 4 is fixed to the position 8b (retraction amount L0) drawn from the axial center end portion 8a of the joint outer ring 8 toward the shaft body. In addition, when the constant velocity joint 2 is bent to the maximum operating angle θ by the action of the C-shaped groove 6 and the first mountain 7 and the adjustment of the inner diameter of the bellows valley portion 3b, on the compression side (3-com) of the bellows portion 3 Since the bellows valley portion (a part thereof) rides on the outer peripheral surface 8 d of the joint outer ring 8, the axial side end portion 8 a of the joint outer ring 8 and the small-diameter fixing portion 5 are on the compression side of the flexible boot 1. It is not necessary to secure the dimensions for accommodating the bellows portion 3-com and the overall length of the flexible boot 1 can be shortened. Further, the bellows valley portion 3b-1 near the joint outer ring 8 of the flexible boot 1 (closest to the joint outer ring 8) is not pressed against the axial end 8a of the joint outer ring 8, and the bellows valley portion 3b-1 is not pressed. Abnormal wear is prevented.

  In addition, although the above-mentioned form is an example of the suitable form of this invention, it is not limited to this, A various deformation | transformation implementation is possible in the range which does not deviate from the summary of this invention. For example, in the present embodiment, the bellows portion 3 has three bellows valley portions 3b-1, 3b-2, 3b-3, and among these bellows valley portions 3b, the first valley portion 3b-1 and the second valley portion 3b-. 2 is made to run on the outer peripheral surface 8d of the joint outer ring 8, but only the first valley portion 3b-1 may be made to ride on the outer peripheral surface 8d, or the three bellows valley portions 3b-1, 3b. -2 and 3b-3 may all run on the outer peripheral surface 8d. In order to shorten the overall length of the flexible boot 1, it is preferable that more than half of the plurality of bellows valley portions 3b ride on the outer circumferential surface 8d, while all the plurality of bellows valley portions 3b are disposed on the outer circumferential surface 8d. If it is made to ride, the first mountain 7 becomes excessively large and space saving may be adversely affected.

  Moreover, although the case where the bellows part 3 has three bellows valley parts 3b-1, 3b-2, 3b-3 is given as an example in the present embodiment, the number of bellows valley parts 3b is limited to three. Rather, it may be two or four or more.

  When there are two bellows valley portions 3b (first valley portion 3b-1 and second valley portion 3b-2 in order from the first mountain 7 side), bellows valley portions 3b-1, 3b-2 are provided. May be made to ride on the outer peripheral surface 8d of the joint outer ring 8, but only the first valley portion 3b-1 is made to ride on the outer peripheral surface 8d for the above-described reason of suppressing the maximization of the first mountain 7. It is preferable to make it.

  Further, there are four bellows valley parts 3b (in order from the first mountain 7 side, the first valley part 3b-1, the second valley part 3b-2, the third valley part 3b-3, and the fourth valley part 3b-4). ), All of the bellows valleys 3b-1, 3b-2, 3b-3, 3b-4 may ride on the outer peripheral surface 8d of the joint outer ring 8, but the maximum of the first mountain 7 For the above-described reason of suppression of conversion, only the first valley 3b-1 and the second valley 3b-2, or the first valley 3b-1, the second valley 3b-2, and the third valley 3b-3 It is preferable that only the hill is run on the outer peripheral surface 8d.

  Further, when the number of bellows valley portions 3 b is five or more, the number of bellows valley portions 3 b in a range that is not less than half of the plurality of bellows valley portions 3 b and not the total number is run on the outer peripheral surface 8 d of the joint outer ring 8. It is preferable to do so.

DESCRIPTION OF SYMBOLS 1 Flexible boot 2 Constant velocity joint 3 Bellows part 3b Bellows valley part 3b-1 1st valley part 3b-2 2nd valley part 4 Large diameter fixed part 5 Small diameter fixed part 6 C-shaped groove 7 First mountain 8 Joint outer ring 8a Axis End in the direction of the heart 8b Pull-in position 8d Outer peripheral surface

Claims (4)

  A constant velocity joint device having a constant velocity joint having a joint outer ring and a shaft and a flexible boot mounted so as to cover the joint portion of the constant velocity joint, wherein the flexible boot has a plurality of bellows and valley portions. A bellows portion, a large-diameter fixing portion and a small-diameter fixing portion for attaching both ends of the bellows portion to the joint outer ring or the shaft, and the large-diameter fixing portion between the large-diameter fixing portion and the bellows portion; A C-shaped groove that is connected and a first peak that rises from an end of the C-shaped groove, and the large-diameter fixing portion is fitted to the joint outer ring and the small-diameter fixing portion is fitted to the shaft and fixed. Is attached to the constant velocity joint, and the large-diameter fixed portion extends from the axial direction end of the joint outer ring to the thickness of the C-shaped groove and the end of the first peak. The first trough portion connected to the first trough portion and the second trough portion adjacent to the first trough portion are fixed to a position drawn to the shaft body side of the joint outer ring for a total amount or more. The joint in which the inner diameter of the valley portion has moved to the bellows portion side by the sum of the thickness of the C-shaped groove and the thickness of the first valley portion from the end portion on the bellows portion side of the large-diameter fixed portion On the side facing the point A1, the development length of the membrane of the flexible boot from the point A1 on the outer peripheral surface of the outer ring and the end on the bellows part side of the large-diameter fixed part to the center of the valley bottom of the first valley part A line segment connecting a point B1 parallel to the axis of the shaft when the constant velocity joint is bent at the maximum operating angle from the end of the large diameter fixing portion on the bellows portion side and the axis of the joint outer ring. It is set to be longer than the chord length d1 of the position C1 where the end face in the central direction intersects, and The inner diameter of the second valley portion is the sum of the thickness of the C-shaped groove, the thickness of the first valley portion, and the thickness of the second valley portion from the end portion on the bellows portion side of the large-diameter fixed portion. The point A2 on the outer peripheral surface of the joint outer ring that has moved to the bellows part side and the end of the large diameter fixing part on the bellows part side to the center of the valley bottom of the second valley part. A point where the unfolded length is parallel to the axis of the shaft when the constant velocity joint is bent at the maximum operating angle from the end of the large-diameter fixed portion on the side facing the point A2 on the bellows portion side. The line segment connecting B2 and the axial length end face of the joint outer ring are set to be longer than the chord length d2 of the position C2, and then the position C1 is a radius of the joint outer ring as viewed from the point A1. In the case of the opposite side across the position, the inner diameter of the first trough is the string The first trough and the second trough are set on the compression side of the bellows portion when the constant velocity joint is bent to the maximum operating angle, not the length d1, and larger than the outer diameter of the joint outer ring. A constant velocity joint device that rides on the outer peripheral surface of the outer ring.   The constant velocity joint device according to claim 1, wherein the flexible boot has two, three, or four bellows valley portions in total.   A constant velocity joint device having a constant velocity joint having a joint outer ring and a shaft and a flexible boot mounted so as to cover the joint portion of the constant velocity joint, wherein the flexible boot has a plurality of bellows and valley portions. A bellows portion, a large-diameter fixing portion and a small-diameter fixing portion for attaching both ends of the bellows portion to the joint outer ring or the shaft, and the large-diameter fixing portion between the large-diameter fixing portion and the bellows portion; A C-shaped groove that is connected and a first peak that rises from an end of the C-shaped groove, and the large-diameter fixing portion is fitted to the joint outer ring and the small-diameter fixing portion is fitted to the shaft and fixed. Is attached to the constant velocity joint, and the large-diameter fixed portion extends from the axial end of the joint outer ring to the thickness of the C-shaped groove and the joint. The inner diameter of the first valley portion connected to the end portion of the first peak is fixed to a position drawn to the shaft body side of the joint outer ring over the total thickness of the bellows valley portion riding on the outer peripheral surface of the ring, On the outer peripheral surface of the joint outer ring moved to the bellows part side by the total thickness of the C-shaped groove and the thickness of the first valley from the end of the large diameter fixing part on the bellows part side. The development length of the membrane of the flexible boot from the point A1 and the end of the bellows portion side of the large-diameter fixing portion to the central position of the valley bottom of the first trough portion of the large-diameter fixing portion on the side facing the point A1 A line segment connecting a point B1 taken parallel to the shaft center of the shaft when the constant velocity joint bends to the maximum operating angle from the end of the bellows side, and an end surface in the axial direction of the joint outer ring Is set to be longer than the chord length d1 of the position C1 where The inner diameter of the second valley portion adjacent to the first valley portion is such that the thickness of the C-shaped groove, the thickness of the first valley portion, and the second valley from the end of the bellows portion side of the large-diameter fixed portion. From the point A2 on the outer peripheral surface of the joint outer ring moved to the bellows portion side by the total thickness of the portion and the end portion on the bellows portion side of the large-diameter fixed portion to the center of the valley bottom of the second valley portion The shaft of the shaft when the constant velocity joint bends to the maximum operating angle from the end of the large-diameter fixed portion on the side facing the point A2 on the side facing the point A2 It is set to be longer than the chord length d2 of the position C2 where the line segment connecting the point B2 parallel to the center and the end face of the joint outer ring in the axial direction end, and further adjacent to the second trough. When riding on the outer peripheral surface of the joint outer ring after the third trough, the same as above An inner diameter after the third valley is set, and when the position C1 is on the opposite side across the radial position of the joint outer ring as viewed from the point A1, the inner diameter of the first valley is It is set not to the chord length d1 but to the outer diameter of the joint outer ring, and when the constant velocity joint is bent to the maximum operating angle, the first valley portion and the second valley portion are arranged on the compression side of the bellows portion. In addition, the constant velocity joint device is characterized in that a valley portion after the third valley portion rides on an outer peripheral surface of the joint outer ring.   4. The constant velocity according to claim 3, wherein the number of bellows valley portions of the flexible boot is four or more in total, and more than half of the four bellows valley portions ride on the outer peripheral surface of the joint outer ring. Joint device.

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