JP2010064093A - Caulking holding structure, caulking holding method, caulking roller and caulking machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the holding force for holding a bearing by increasing the remaining axial force of a bearing holder after caulking the bearing. <P>SOLUTION: The plastic flow of a caulked portion 8b to a fore end side of an end of the bearing holder 8 is suppressed by the caulking performed by a roller 24 having a pressing circumferential surface 26b of the conical shape, and the plastic flow is promoted on a circumferential wall part on the opposite side without any folding. Thus, the axial elastic deformation of the bearing holder 8 can be reduced, and the difference between the axial elastic deformation and the elastic deformation of an outer race 14a can be increased in comparison with that in the conventional caulking. After completing the caulking, the remaining axial force at the bearing holder 8 is increased more than that in the regular caulking. Thus, the holding force for holding the outer race 14a can be increased. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a caulking holding structure and a caulking holding method for holding and holding a member to be held in the axial direction of a cylinder by an abutting surface inside the cylinder and a caulking part at the end of the cylinder, and further to the caulking holding method. The present invention relates to a caulking roller and a caulking machine to be used.

  2. Description of the Related Art A rotation-linear motion conversion actuator is known that has an internal combustion engine or the like as a driving target device and is attached to apply a linear motion driving force thereto (see, for example, Patent Documents 1 and 2). These patent documents 1 and 2 are disclosing the rotation-linear motion conversion actuator which drives the valve lift apparatus of an internal combustion engine. A rotation shaft is rotatably supported through a bearing in the main body case of the rotation-linear motion conversion actuator. The rotary shaft is rotated by a motor drive, whereby the screw shaft moves linearly and moves in the axial direction, thereby driving the valve lift device.

  In Patent Documents 1 and 2, in order to fix a bearing for rotatably supporting the rotating shaft in the housing, an annular support member is arranged inside the housing, and this support member is bolted to the inner surface of the housing. Yes.

Since the annular support member for fixing the bearing is arranged inside the housing and fastened with bolts in this way, the physique of the housing is easily increased in size. A method of supporting the bearing by combining this with caulking (see, for example, Patent Documents 3, 4, and 5) can be considered.
Japanese Unexamined Patent Publication No. 2007-303408 (5th page, FIG. 1) JP 2007-303479 A (5th page, FIG. 2) Japanese Patent Laying-Open No. 2001-50291 (page 3-4, FIG. 2) JP 2000-6610 (page 6, FIG. 1) Japanese Patent Laid-Open No. 2002-21867 (page 3, FIG. 3)

  However, when holding a member to be held such as a bearing that requires a certain level of clamping force with the housing, the holding force for holding may be insufficient if the housing is simply crimped and clamped. That is, even if the pressure during caulking is increased to increase the clamping force by the caulking portion of the housing, most of this increase in pressure is caused by the plastic flow component in the radial direction perpendicular to the axial direction at the caulking portion. Contributed to the increase. This has caused a problem that the residual axial force of the housing, which should finally play a role of generating the clamping force, cannot be sufficiently increased.

  An object of the present invention is to improve a clamping force for holding a held member by increasing a residual axial force after caulking.

In the following, means for achieving the above object and its effects are described.
In the caulking holding structure according to claim 1, the held member is formed in the axial direction of the cylinder by the contact surface provided inside the cylinder and the caulking part formed by bending the end of the cylinder. A caulking holding structure that is held inside the cylindrical body in a sandwiched state, wherein the caulking portion is caulked at an end portion of the cylindrical body in a state in which plastic flow toward the distal end side of the end portion of the cylindrical body is suppressed. It is formed by being processed.

The caulking portion is not formed by simply bending the end portion of the cylinder by caulking, but is formed by bending in a state in which the plastic flow toward the end of the end portion of the cylinder is suppressed.
Thus, the plastic flow generated by caulking while the plastic flow toward the end of the end portion is suppressed is directed to the side opposite to the end of the end portion, i.e., the region that is not bent. Will increase.

  As described above, in the present invention, when the crimping pressure bends the end portion of the cylindrical body, the plastic flow in the portion that is not bent on the side opposite to the tip end side of the end portion becomes larger than usual. Therefore, the proportion of elastic deformation is reduced in the deformation in the portion that is not bent during caulking.

  For this reason, the caulking process is completed and the held member returns from the compressed state due to the elastic deformation at the time of pressurization, and at the same time, the unfolded portion of the cylinder also tries to recover from the compressed state. The plastic deformation of the cylinder does not return. In the present invention, the portion that is not bent as described above has a larger plastic deformation than usual, and the elastic deformation is smaller accordingly.

  Therefore, the difference in the amount of elastic deformation in the axial direction between the held member and the cylinder holding the member is enlarged, and after the caulking process is completed, the remaining shaft in the cylinder is compared with the normal caulking process. The power can be increased. Thus, the caulking holding structure of the present invention can improve the clamping force for holding the held member.

  In the caulking holding structure according to claim 2, in the first aspect, the end portion of the cylindrical body is prevented from extending toward the distal end side of the end portion. It is characterized by realizing a state in which plastic flow is suppressed.

In this way, suppression of plastic flow toward the end of the end of the cylinder during caulking can be achieved by suppressing the end of the cylinder from extending toward the end of the end.
By suppressing the extension toward the tip end side of the end portion, the plastic flow moves to the unfolded portion, and the plastic flow in this portion can be increased. As a result, the difference in the amount of elastic deformation in the axial direction between the held member and the cylinder is enlarged as described above, and after the caulking process is completed, the cylinder has a residual axial force compared to the normal caulking process. Will be big. Therefore, the clamping force for holding the held member can be improved.

  In the caulking holding structure according to claim 3, in claim 1 or 2, the cylindrical body is cylindrical, and the caulking portion is formed by caulking the end of the cylindrical body with a roller. In addition, the roller prevents the tilting of the pressurizing peripheral surface that bends and presses the end of the cylindrical body and the region adjacent to the pressurizing peripheral surface and the region that is bent at the end of the cylindrical body. And a plastic flow toward the tip end side of the cylindrical body is suppressed by reducing the distance between the pressurizing circumferential surface and the held member on the bent tip side. It is characterized by realizing the state.

  By setting the shape of the caulking roller and the distance between the pressure peripheral surface and the member to be held in this way, it is possible to suppress the plastic flow toward the end of the end of the cylindrical body during caulking. The plastic flow can be increased and the residual axial force in the cylinder can be increased. Therefore, the clamping force for holding the held member can be improved.

  In the caulking holding structure according to claim 4, in claim 3, the pressure peripheral surface of the roller has a shape in which a peripheral diameter is gradually increased on the bending leading end side, so that the pressure peripheral surface of the roller and the roller The present invention is characterized in that a state in which the distance between the held member and the held member is reduced on the bent tip side is realized.

  In this way, by using a roller with a circumferential surface whose diameter is gradually increased on the bent tip side, it is opposite to the suppression of plastic flow toward the tip end of the cylinder during caulking. The plastic flow to the side can be increased. Therefore, the residual axial force in the cylinder can be increased, and the clamping force for holding the held member can be improved.

The caulking holding structure according to claim 5 is characterized in that, in claim 4, the pressure peripheral surface is a conical surface.
In this way, by forming the pressure peripheral surface of the roller as a conical surface, it is possible to realize a shape in which the peripheral diameter of the pressure peripheral surface gradually increases on the bending tip side.

  The caulking holding structure according to claim 6 is characterized in that, in claim 5, the angle of the conical surface is formed at an angle of 5 ° or less and greater than 0 ° with respect to the axial direction of the roller. .

  The angle of the conical surface, that is, the angle between the axis of the cone and the generatrix is 5 ° or less and greater than 0 °, so that the roller is a conical surface. It is possible to increase the plastic flow to the opposite side of the plastic flow suppression.

The caulking holding structure according to claim 7 is characterized in that, in claim 5, the angle of the conical surface is formed in the range of 2 ° to 5 ° with respect to the axial direction of the roller. .
As the angle of the conical surface, by using a roller having a conical surface inclined in the range of 2 ° to 5 °, the plastic flow to the opposite end and the plastic flow to the end of the end of the cylinder during caulking are suppressed. A caulking holding structure in which the increase in flow is particularly effective can be obtained.

  The caulking holding structure according to claim 8, wherein the end surface of the member to be held is in a state of being close to the pressurizing circumferential surface on the bent distal end side, so that the pressurizing circumference of the roller is increased. The present invention is characterized in that a state is realized in which the distance between the surface and the held member is reduced on the bent tip side.

  It is good also as a structure which the end surface side of the to-be-held member is approaching with respect to a pressurization surrounding surface in the bending front end side. This also makes it possible to suppress plastic flow toward the end of the end of the cylindrical body during caulking and increase plastic flow toward the opposite side. Therefore, the caulking holding structure of the present invention can be formed without using a roller deformed so that the shape of the pressurizing peripheral surface bends closer to the held member at the tip end side, and is used for holding the held member. The power can be improved.

  The caulking holding structure according to claim 9, wherein the end surface of the member to be held has a shape having a step which becomes higher on the bent leading end side, so that the pressing peripheral surface of the roller and the to-be-held portion are held. The present invention is characterized in that a state in which the distance from the member is reduced on the bent front end side is realized.

  Thus, it is good also as a structure which the end surface side of the to-be-held member approached with respect to the pressurization surrounding surface by the bending front end side by the level | step difference of to-be-held member. This also makes it possible to suppress plastic flow toward the end of the end of the cylindrical body during caulking and increase plastic flow to the opposite side.

  The caulking holding structure according to claim 10, wherein the held member is a bearing according to any one of claims 1 to 9, and the cylindrical body includes a rotating member arranged rotatably by the bearing. Or a bearing holder disposed in the housing.

  Thus, the present invention can be applied to the relationship between the housing or the bearing holder and the bearing. Therefore, in the configuration in which the bearing is clamped between the contact surface of the housing or the bearing holder and the caulking portion, the difference in the amount of elastic deformation in the axial direction between the bearing and the housing or the bearing holder can be increased more than usual. For this reason, after the caulking process is completed, the residual axial force in the housing or the bearing holder becomes larger than that in the normal caulking process, and the clamping force for holding the bearing can be improved.

  In order to improve the clamping force in this way, it is not necessary to prepare a separate mechanism for attaching the bearing to the housing or the bearing holder with a bolt or the like, so that the housing or the bearing holder can be reduced in size.

  The caulking holding structure according to claim 11, wherein the bearing and the housing or the bearing holder are a bearing and a housing or a bearing holder in a rotation-linear motion conversion actuator, and the rotation-linear motion conversion actuator The rotating member is disposed in the housing or the bearing holder attached to the device to be driven so as to be rotatable via the bearing, and an output shaft that moves in the axial direction of the cylinder by the rotation of the rotating member is removed from the housing. It arrange | positions in the state protruded outside, and transmits a driving force from this output shaft to the said drive target apparatus, It is characterized by the above-mentioned.

  The present invention can be applied to such a rotation-linear motion conversion actuator. As a result, a large residual axial force can be set in the housing or the bearing holder, and the bearing can be held securely. For this reason, a rotation-linear motion conversion actuator can be reduced in size. Furthermore, the entire drive target device can also contribute to downsizing.

  In the caulking holding structure according to claim 12, in claim 11, the rotating member is a nut of a planetary differential screw type rotation-linear motion conversion mechanism, the output shaft is a sun shaft, and the nut and the sun shaft Since a planetary shaft is disposed between them, rotation-to-linear motion conversion is performed by a meshing mechanism between the sun shaft, the planetary shaft, and the nut formed in the nut.

  The rotation-linear motion conversion actuator may be configured as such a planetary differential screw type rotation-linear motion conversion mechanism. With such a rotation-linear motion conversion actuator, a large residual axial force can be set on the housing or bearing holder, the bearing can be held securely, the rotation-linear motion conversion actuator can be downsized, and the entire drive target device can also be reduced. Contributes to downsizing.

The caulking holding structure according to claim 13 is characterized in that, in claim 11 or 12, the drive target device is an internal combustion engine.
As a result, the entire internal combustion engine can be reduced in size.

  In the caulking and holding method according to claim 14, the member to be held is inserted and arranged up to the contact surface installed inside the cylinder, and the end of the cylinder is bent by caulking to form a caulking portion. A caulking holding method in which a held member is clamped between a caulking portion and a contact surface in the cylinder axis direction and held in the cylinder, and the plastic flow toward the tip end side of the cylinder during the caulking process is performed. It is characterized by suppressing.

  Plastic flow occurs by being bent during caulking. However, in this case, since the plastic flow to the tip end side of the cylindrical body is suppressed, the plastic flow in this portion is increased toward the side opposite to the tip end side of the end, that is, the unbent region. Become.

  As described above, when the crimping pressure bends the end of the cylindrical body, the plastic flow in the portion that is not bent on the side opposite to the end of the end can be made larger than usual. Therefore, the proportion of elastic deformation can be reduced by that amount in the deformation in the unfolded portion.

  Therefore, the caulking process is completed and the held member returns from the compressed state due to the elastic deformation at the time of pressurization, and at the same time, the unfolded portion of the cylindrical body is restored from the compressed state, so that the held member is A holding state is established between the contact surface and the caulking portion. In this holding state, the plastic deformation is not restored. That is, as described above, the portion that is not bent is larger in plastic deformation than usual, and the elastic deformation is smaller by that amount.

  Therefore, the difference in the amount of elastic deformation in the axial direction between the held member and the cylindrical body is enlarged, and the residual axial force in the cylindrical body is increased as compared with the normal caulking process. As a result, a caulking holding structure that improves the clamping force for holding the member to be held can be formed by the caulking holding method of the present invention.

  In the caulking holding method according to claim 15, in the caulking process according to claim 14, the plastic flow toward the end tip side is suppressed by suppressing the end portion of the cylindrical body from extending toward the end tip side. It is characterized by that.

  By suppressing the extension toward the tip end side of the end portion, the plastic flow moves to the unfolded portion, and the plastic flow in this portion can be increased. As a result, the difference in the amount of elastic deformation in the axial direction between the held member and the cylindrical body is enlarged, and the residual axial force of the cylindrical body becomes larger than that of normal caulking. Thus, a caulking holding structure that improves the clamping force for holding the held member can be realized.

  In the caulking holding method according to claim 16, in claim 14 or 15, the cylinder is cylindrical, and the caulking process is caulking with a roller, and the roller bends an end of the cylinder. And a supporting surface for preventing tilting of a region adjacent to the region bent at the end of the cylindrical body adjacent to the pressing peripheral surface. The distance between the peripheral surface and the held member is reduced on the bent tip side to suppress plastic flow toward the end tip side.

  By setting the shape of the caulking roller and the distance between the pressure peripheral surface and the member to be held in this way, the plastic flow is suppressed to the tip end side of the cylinder and the plastic flow is increased to the opposite side. This makes it possible to realize a caulking holding structure that increases the residual axial force in the cylinder and improves the clamping force for holding the held member.

  The caulking and holding method according to claim 17 is characterized in that, in claim 16, the roller has a pressing peripheral surface having a shape in which a peripheral diameter is gradually increased on the bending tip side.

  As described above, by using a roller having a pressure peripheral surface having a shape in which the peripheral diameter gradually increases on the bending tip side, plastic flow suppression to the end tip side of the cylindrical body and plasticity to the opposite side are performed. It is possible to increase the flow, increase the residual axial force in the cylinder, and realize a caulking holding structure that improves the clamping force for holding the held member.

The caulking holding method according to claim 18 is characterized in that, in claim 17, the pressurizing peripheral surface is a conical surface.
Thus, by making the pressure peripheral surface of the roller a conical surface, the peripheral diameter of the pressure peripheral surface can be gradually increased on the bent tip side, and the plastic flow toward the tip end side of the cylindrical body It is possible to increase the plastic flow to the opposite side of suppression.

  In the caulking and holding method according to claim 19, in claim 18, the angle of the conical surface is formed at an angle of 5 ° or less and greater than 0 ° with respect to the axial direction of the roller. .

  By using a conical roller inclined at a conical surface angle, that is, an angle formed between a cone axis and a generatrix and not larger than 5 ° and larger than 0 °, it is possible to move the end of the cylinder toward the distal end side during caulking. The plastic flow can be increased to the opposite side of the plastic flow suppression.

  In the caulking holding method according to claim 20, in claim 18, the angle of the conical surface is formed in an angle range of 2 ° to 5 ° with respect to the axial direction of the roller. .

  By using a conical roller inclined in the range of 2 ° to 5 ° as the angle of the conical surface, the suppression of plastic flow toward the end of the end of the cylinder is particularly effective. A sufficient increase in plastic flow is obtained.

  The caulking and holding method according to claim 21, wherein the member to be held has an end surface in a shape close to the pressurizing circumferential surface on the bent leading end side. What is used is that the space between the pressure peripheral surface of the member and the held member is reduced on the bent tip side.

  Instead of the pressure peripheral surface side of the roller, a held member whose end surface side is bent and is close to the pressure peripheral surface of the roller may be used. This also makes it possible to suppress plastic flow toward the end of the end of the cylinder and increase plastic flow toward the opposite side.

  23. The caulking and holding method according to claim 22, wherein the held member has an end surface formed with a step which becomes higher on the bent leading end side, so that the pressure is applied on the bent leading end side. What used the end surface of the shape brought close to the peripheral surface is used.

By caulking using the held member having the step as described above, the plastic flow toward the end of the end of the cylindrical body can be sufficiently suppressed, and an increase in the plastic flow toward the opposite side can be sufficiently obtained.
The caulking and holding method according to claim 23, wherein the member to be held is a bearing according to any one of claims 14 to 22, and the cylindrical body includes a rotating member disposed rotatably by the bearing. Or a bearing holder disposed in the housing.

  Thus, the present invention can be applied to hold the bearing in the housing or the bearing holder, and the difference in the amount of elastic deformation in the axial direction between the bearing and the housing or the bearing holder can be increased more than usual. For this reason, the residual axial force in the housing or the bearing holder is increased as compared with a normal caulking process, and a caulking holding structure that improves the clamping force for holding the bearing can be realized.

  Thus, the caulking holding structure with improved clamping force can be formed without preparing a separate mechanism for mounting the bearing in the housing or bearing holder with a bolt or the like, so that the entire housing or bearing holder can be reduced in size.

  25. The caulking and holding method according to claim 24, wherein, in claim 23, the bearing and the housing or the bearing holder are a bearing and a housing or a bearing holder in a rotation-linear motion conversion actuator, and the rotation-linear motion conversion actuator. The rotating member is disposed in the housing or the bearing holder attached to the device to be driven so as to be rotatable via the bearing, and an output shaft that moves in the axial direction of the cylinder by the rotation of the rotating member is removed from the housing. It arrange | positions in the state protruded outside, and transmits a driving force from this output shaft to the said drive target apparatus, It is characterized by the above-mentioned.

  The present invention can be applied to the manufacture of such a rotation-linear motion conversion actuator. As a result, a large residual axial force can be set in the housing or the bearing holder, and a caulking holding structure in which the bearing can be reliably held can be realized. Therefore, it is possible to reduce the size of the rotation / linear motion conversion actuator, and it is also possible to contribute to the size reduction of the entire drive target device.

  In the caulking holding method according to claim 25, in claim 24, the rotating member is a nut of a planetary differential screw type rotation-linear motion converting mechanism, the output shaft is a sun shaft, Since a planetary shaft is disposed between them, rotation-to-linear motion conversion is performed by a meshing mechanism between the sun shaft, the planetary shaft, and the nut formed in the nut.

The rotation-linear motion conversion actuator may be configured as such a planetary differential screw type rotation-linear motion conversion mechanism, and the same actions and effects as in the twenty-fourth aspect are produced.
In the caulking and holding method according to a twenty-sixth aspect, in the twenty-fourth or twenty-fifth aspect, the drive target device is an internal combustion engine.

As a result, the entire internal combustion engine can be reduced in size.
According to a 27th aspect of the present invention, there is provided a caulking roller that is formed by bending an end portion of a cylindrical tubular body to form a caulking portion, so that a contact surface installed inside the tubular body and the caulking portion A roller used for caulking to hold the holding member in the cylinder axial direction, wherein the roller bends an end of the cylinder and pressurizes the pressure circumferential surface, and is adjacent to the pressure circumferential surface. A support surface that prevents tilting of a region adjacent to the region that is bent at the end of the cylindrical body, and the pressure peripheral surface is a conical surface, whereby the pressure peripheral surface is bent and held by the tip side. It is characterized by being close to the member.

  By using this roller for caulking, it is possible to suppress the plastic flow toward the end of the end of the cylinder during caulking and increase the plastic flow to the opposite side, thereby increasing the residual axial force in the cylinder. The clamping force for holding the held member can be improved.

  The caulking roller according to claim 28 is characterized in that, in claim 27, the angle of the conical surface is 5 ° or less and greater than 0 ° with respect to the axial direction of the roller.

  The angle of the conical surface, that is, the angle between the axis of the cone and the generatrix is 5 ° or less and greater than 0 °, so that the roller is a conical surface. It is possible to increase the plastic flow to the opposite side of the plastic flow suppression.

A caulking roller according to a twenty-ninth aspect is characterized in that, in the twenty-seventh aspect, the angle of the conical surface is an angle in a range of 2 ° to 5 ° with respect to the axial direction of the roller.
As the angle of the conical surface, by using a roller having a conical surface inclined in the range of 2 ° to 5 °, the plastic flow to the opposite end and the plastic flow to the end of the end of the cylinder during caulking are suppressed. Increased flow can be particularly effective.

  A caulking machine according to a thirty-third aspect is provided with the caulking roller according to any one of the twenty-seventh to twenty-ninth aspects, and an end of the cylinder is added in a direction perpendicular to the axis of the caulking roller. The caulking portion is formed by pressing and bending.

  Use of the caulking roller according to any one of claims 27 to 29 as a caulking machine enables suppression of plastic flow to the tip end side of the cylindrical body and increase of plastic flow to the opposite side during caulking. Thus, it is possible to perform caulking that can increase the residual axial force in the cylinder, and this can improve the clamping force that holds the member to be held in the cylinder.

[Embodiment 1]
The longitudinal cross-sectional view shown in FIG. 1 represents the structure of the rotation-linear motion conversion actuator (henceforth an "actuator") 2 to which the invention mentioned above was applied. The actuator 2 is attached to the outer surface of a cylinder head or a cam carrier using an internal combustion engine as a device to be driven. In particular, the actuator 2 drives a control shaft provided in the variable valve mechanism in the axial direction in order to drive the variable valve mechanism on the cylinder head. Here, the actuator 2 is attached to the outer peripheral surface 4a of the cam carrier 4 as shown by a one-dot chain line.

  In the housing 6 of the actuator 2, a bearing holder 8 is bolted to the front side (F side in the drawing), and a stator 10 is bolted to the rear side (B side in the drawing). The rear end side of the housing 6 is closed by the control panel 12.

  A bearing 14 is attached to the rear end side inside the bearing holder 8. The bearing holder 8 rotatably supports a nut 16 a constituting the outer periphery of the planetary differential screw type rotation-linear motion conversion mechanism 16 via the bearing 14.

  The planetary differential screw type rotation-linear motion conversion mechanism 16 is disposed in the inner space of the housing 6 over the entire length in the axial direction. As shown in the partially broken perspective view of FIG. 2, the planetary differential screw type rotation-linear motion converting mechanism 16 includes a nut 16a as a rotating member, an output shaft 16b as a sun shaft, and between the nut 16a and the output shaft 16b. Is provided with a planetary shaft 16c. The nut 16a and the planetary shaft 16c are engaged with each other by a gear and a screw. Similarly, the planetary shaft 16c and the output shaft 16b are also engaged by a gear and a screw.

  A rotor 18 is attached to the rear end of the nut 16a by press-fitting as shown in FIG. 1, and the rotor 18 is rotationally driven through the stator 10 by the drive signal from the control panel 12, thereby the nut. 16a rotates around the axis. The rotation of the nut 16a causes the planetary shaft 16c to revolve around the output shaft 16b while rotating. Due to the differential action of the screws generated by the rotation and revolution of the planetary shaft 16c, the output shaft 16b, which is spline-fitted with the tip of the bearing holder 8 and is prevented from rotating around the axis, moves in the axial direction. . In conjunction with the axial movement of the output shaft 16b, the control shaft of the variable valve mechanism existing in the space in the cam carrier 4 moves in the axial direction (arrow FB direction). The maximum valve lift amount of the intake valve is continuously adjusted in each cylinder.

  The bearing 14 that supports the entire planetary differential screw type rotation-linear motion conversion mechanism 16 has an outer race 14a, which has a contact surface 8a installed inside the bearing holder 8 by a step, and a caulking portion 8b at the rear end. And are held in the axial direction. As a result, the entire planetary differential screw type rotation / linear motion conversion mechanism 16 is held at the reference position in the housing 6 via the bearing holder 8.

  Here, the caulking process for forming the caulking portion 8b will be described. FIG. 3 shows the assembled state immediately before caulking. Immediately before the caulking process, the rear end side of the bearing holder 8 (corresponding to a cylindrical cylindrical body) is an unprocessed portion 8x having a cylindrical shape. Therefore, the rear end side is open, and the planetary differential screw type rotation-linear motion converting mechanism 16 is inserted into the bearing holder 8 from the rear end side. Prior to insertion, the planetary differential screw type rotation-linear motion conversion mechanism 16 is in a state of being fitted with a bearing 14 on the outer periphery of a nut 16a and fixed by a snap ring 20 or the like. In addition, the seal ring 22 is also inserted in advance from the rear end side and disposed at a predetermined position. The seal ring 22 may be disposed at the same time when the planetary differential screw type rotation-linear motion conversion mechanism 16 is inserted by being fitted to the planetary differential screw type rotation-linear motion conversion mechanism 16 in advance.

  The configuration shown in FIG. 3 is arranged in a roll caulking machine, and caulking is performed on the unprocessed portion 8x by the caulking roller 24 as shown in FIG. In FIG. 4, the rotation axis A of the caulking roller 24 is shown in a state parallel to the paper surface.

  The roller 24 is rotated on the rotation axis A and simultaneously revolved around the axis B of the bearing holder 8, and the unprocessed portion 8 x is pressed by the caulking surface 26 formed on the roller 24. As a result, the unprocessed portion 8x is bent along the end surface 14b of the outer race 14a to form a crimped portion 8b as shown in FIG. As a result, the outer race 14 a receives a clamping pressure from the contact surface 8 a and the caulking portion 8 b, and the entire bearing 14 is held in the bearing holder 8. As a result, the planetary differential screw type rotation-linear motion conversion mechanism 16 is rotatably supported in the bearing holder 8.

  Here, both the bearing holder 8 and the outer race 14a are made of steel, but the outer race 14a is made of a harder steel than the bearing holder 8. For example, the bearing holder 8 is made of general stainless steel or the like, and the outer race 14a is made of high hardness steel such as high carbon chrome steel.

  Here, FIG. 6 shows a partially enlarged shape of the caulking surface 26 of the roller 24. 6A is an enlarged view of the main part of the roller 24, and FIG. 6B is an enlarged view of the main part during caulking. As shown in the drawing, in the caulking surface 26, the peripheral wall support surface 26a has an outer region 8c adjacent to the unprocessed portion 8x in the peripheral wall portion that is not bent when the unprocessed portion 8x is caulked. It is the side which prevents falling down. Therefore, the peripheral wall support surface 26 a is an annular flat surface that is perpendicular to the rotation axis A and parallel to the axis B of the bearing holder 8. Further, a pressurizing peripheral surface 26b formed around the rotation axis A and bending the unprocessed portion 8x toward the end surface 14b of the outer race 14a is connected to the caulking surface 26, and the pressurizing peripheral surface 26b and the peripheral wall support surface 26a are connected. A round pressure-shaped peripheral surface 26c is formed. Of these, the pressurizing peripheral surface 26b is not a cylindrical surface parallel to the rotation axis A, but forms a conical surface that expands toward the tip side. Here, the diameter of the pressurizing peripheral surface 26b is increased at an inclination angle θ. Here, the inclination angle θ is a value larger than 0 ° and not larger than 5 °. Particularly effective in the present embodiment is a range of θ = 2 ° to 5 °.

  Therefore, at the time of caulking, when the unprocessed portion 8x is bent toward the end surface 14b of the outer race 14a, as shown in FIG. 6B, the bent unprocessed portion 8x, that is, the tip of the caulking portion 8b. The distance (d1, d2) between the end surface 14b of the outer race 14a and the pressure peripheral surface 26b of the roller 24 becomes smaller (d1> d2).

  For this reason, at the time of caulking, the caulking portion 8b causes plastic flow as indicated by the broken line in FIG. 6B, but the plastic flow toward the tip side of the caulking portion 8b is suppressed. As a result of this plastic flow suppression to the tip side, the plastic flow to the opposite side, that is, the peripheral wall portion that is not bent, increases as indicated by the solid line.

  That is, of the deformation in the bearing holder 8 that occurs during the caulking process, the plastic deformation in the axial direction of the peripheral wall portion including the adjacent region 8c of the caulking portion 8b increases, and the axial direction of the peripheral wall portion corresponding to this increases. The amount of elastic deformation at will decrease. The outer race 14a of the bearing 14 is a hard material and is only elastically deformed.

  As a result, the elastic deformation amount of the outer race 14a of the bearing 14 is the same as that of θ = 0 °, that is, when the outer race 14a of the bearing 14 is caulked, but the elastic deformation amount of the bearing holder 8 is reduced. Can be reduced.

According to the first embodiment described above, the following effects can be obtained.
(I). By performing the caulking process using the caulking machine provided with the roller 24 as described above, the plastic flow toward the end of the end of the bearing holder 8 is suppressed during caulking, and this prevents the other side from being bent. The plastic flow is promoted in the peripheral wall portion. Therefore, since the amount of elastic deformation in the axial direction of the bearing holder 8 can be reduced during the caulking process, the difference from the amount of elastic deformation of the outer race 14a can be enlarged as compared with the conventional caulking process.

  When the caulking process is completed, the outer race 14a returns from the compressed state due to the elastic deformation at the time of pressurization, and at the same time, the peripheral wall portion of the bearing holder 8 tries to recover from the compressed state. In this case, since the amount of plastic deformation does not return to the original value, the residual axial force in the bearing holder 8 becomes larger after the caulking process than in the normal caulking process. Thereby, the clamping force for holding the outer race 14a can be improved.

  (B). The pressurizing peripheral surface 26b of the caulking roller 24 forms a peripheral surface that is enlarged toward the tip end side of the caulking portion 8b, here a conical surface. Thereby, the space | interval of the pressurization surrounding surface 26b of the roller 24 and the outer race 14a is made small by the bending front end side. In this way, the plastic flow suppression as described above can be easily performed during the caulking process by the peripheral surface shape of the roller 24.

  In particular, by setting the angle of the conical surface, that is, the angle formed between the axis of the cone and the generatrix within a range of 5 ° or less and greater than 0 °, the plastic flow toward the end of the end of the bearing holder 8 during caulking is performed. Suppression takes place. Among these, by setting in the range of 2 ° to 5 °, the suppression of plastic flow toward the end of the end becomes particularly effective. As a result, as described above, the residual axial force at the bearing holder 8 is increased, and the clamping force for holding the outer race 14a can be improved.

  (C). With the caulking machine using the roller 24 of the present embodiment, a large residual axial force can be obtained even by caulking, and the bearing 14 can be held in the bearing holder 8 with a sufficient fastening force. For this reason, the bolt fastening of the bearing 14 becomes unnecessary, the bearing holder 8 can be reduced in size, and the housing 6 itself of the actuator 2 can also be reduced. Therefore, the whole internal combustion engine using the actuator 2 that employs this planetary differential screw type rotation-linear motion conversion mechanism can also be reduced in size.

[Embodiment 2]
FIG. 7 shows the roller 124 of the present embodiment and the caulking process using the caulking machine using the roller 124. As shown in FIG. 7A, the caulking surface 126 formed on the roller 124 has the same shape as that of the first embodiment with respect to the peripheral wall support surface 126a and the rounded pressure peripheral surface 126c. The pressurizing peripheral surface 126b formed continuously with the rounded pressurizing peripheral surface 126c is not a conical surface as in the first embodiment, but is a cylindrical surface, and the peripheral diameter is the same in the axial direction.

  For the outer race 114a of the bearing, a step 114c that is raised by one step is formed on the end surface 114b that is in contact with the caulking portion 108b. Thereby, the space | interval of the end surface 114b and the pressurization surrounding surface 126b is the state made small on the bending front end side.

The other configuration is the same as that of the first embodiment.
When caulking is performed on the outer race 114a of the bearing using the roller 124, the plastic flow toward the bending tip side of the caulking portion 108b is suppressed by the step surface 114d. As a result, the amount of plastic deformation in the axial direction at the partition wall portion of the bearing holder 108 including the adjacent region 108c of the caulking portion 108b increases, and the amount of elastic deformation decreases accordingly.

According to the second embodiment described above, the following effects can be obtained.
(I). On the roller 124 side, even if the pressurizing peripheral surface 126b has a cylindrical shape, that is, has a shape that does not approach the end surface 114b, the plastic flow is bent by approaching the end surface 114b side as described above. It can be promoted at the peripheral wall portion of the bearing holder 108 that is not. As a result, the amount of elastic deformation in the axial direction of the bearing holder 108 can be reduced, and the difference from the amount of elastic deformation of the outer race 114a can be enlarged as compared with the conventional caulking process.

  Accordingly, after the caulking process is completed, the residual axial force in the bearing holder 108 is increased as compared with the normal caulking process, so that the clamping force for holding the outer race 114a can be improved.

  (B). With such a shape on the bearing 114 side, it is possible to promote plastic deformation of a portion that is not bent by the bearing holder 108. Therefore, the residual axial force at the bearing holder 108 can be increased without changing the caulking surface 126 of the roller 124 from the conventional shape.

(C). The effect (c) of the first embodiment is produced.
[Other embodiments]
(A). In each of the above embodiments, the outer race of the bearing is clamped by the bearing holder, but without using the bearing holder, a caulking portion is formed directly on the housing by caulking and is held directly by the housing. Also good. Also in this case, the effects as described above are produced.

  (B). In the second embodiment, the stepped surface 114d (FIG. 7) rises perpendicularly at the end surface 114b. However, the caulking process is performed in a state where the distance between the end surface 114b and the pressurizing peripheral surface 126b is reduced at the bent front end side. The step surface 114d may be formed in an inclined state.

  In the first embodiment as well, the pressure peripheral surface 26b of the roller 24 is inclined as a conical surface. However, the pressure peripheral surface 26b of the roller 24 has a step at the bent tip side, so that the end surface and the pressure peripheral surface are Caulking may be performed in a state in which the distance from the surface is small on the bent tip side.

  (C). In each of the above embodiments, the mechanism driven by the actuator is a variable valve mechanism that can continuously adjust the maximum valve lift amount of the intake valve provided in the internal combustion engine, but is provided in the internal combustion engine. Alternatively, a variable valve mechanism that can continuously adjust the maximum valve lift of the exhaust valve may be used. Furthermore, the mechanism driven by the actuator is not limited to the variable valve mechanism, and may be another mechanism.

  (D). In the above embodiment, the planetary differential screw type rotation-linear motion conversion mechanism is adopted as the rotation-linear motion conversion mechanism, but a feed screw mechanism may be used.

FIG. 3 is a longitudinal sectional view of the rotation-linear motion conversion actuator according to the first embodiment. FIG. 3 is a partially broken perspective view of a planetary differential screw type rotation-linear motion conversion mechanism used in the rotation-linear motion conversion actuator of the first embodiment. In Embodiment 1, it is a longitudinal cross-sectional view which shows the assembly state just before caulking. FIG. 3 is an explanatory diagram illustrating an arrangement state of the caulking roller and the bearing holder according to the first embodiment. FIG. 3 is an explanatory diagram of a caulking process according to the first embodiment. FIG. 3 is an explanatory diagram illustrating a caulking roller and a caulking state according to the first embodiment. Explanatory drawing which shows the caulking process roller of Embodiment 2, and a caulking process state.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 2 ... Actuator, 4 ... Cam carrier, 4a ... Outer peripheral surface, 6 ... Housing, 8 ... Bearing holder, 8a ... Contact surface, 8b ... Caulking part, 8c ... Adjacent area | region, 8x ... Unprocessed part, 10 ... Stator, 12 ... Control panel, 14 ... Bearing, 14a ... Outer race, 14b ... End face, 16 ... Planetary differential screw type rotation-linear motion conversion mechanism, 16a ... Nut, 16b ... Output shaft, 16c ... Planetary shaft, 18 ... Rotor, 20 ... Snap ring, 22 ... Seal ring, 24 ... Caulking roller, 26 ... Caulking surface, 26a ... Surrounding wall support surface, 26b ... Pressure peripheral surface, 26c ... Round pressure peripheral surface, 108 ... Bearing holder, 108b ... Caulking portion, 108c ... adjacent region, 114 ... bearing, 114a ... outer race, 114b ... end face, 114c ... step, 114d ... step surface 124 ... caulking roller, 126 ... crimping surfaces, 126a ... peripheral wall support surface, 126b ... pressure 圧周 surface, 126c ... round shape pressurizing 圧周 surface.

Claims (30)

The held member is held inside the cylinder while being clamped in the axial direction of the cylinder by a contact surface installed inside the cylinder and a caulking part formed by bending the end of the cylinder. A caulking holding structure,
The caulking holding structure is characterized in that the caulking portion is formed by caulking the end portion of the cylindrical body in a state in which plastic flow toward the tip end side of the cylindrical body is suppressed. The caulking holding structure according to claim 1, wherein an end portion of the cylindrical body is prevented from extending toward the distal end side, thereby suppressing plastic flow toward the distal end side of the cylindrical body. A caulking holding structure characterized by realizing a closed state. 3. The caulking holding structure according to claim 1, wherein the cylindrical body is cylindrical, the caulking portion is formed by caulking an end portion of the cylindrical body with a roller, and the roller is A pressure peripheral surface that bends and pressurizes the end portion of the cylindrical body, and a support surface that prevents tilting of a region adjacent to the pressure peripheral surface and adjacent to the region that is bent at the end portion of the cylindrical body. And a state in which the plastic flow toward the distal end side of the cylindrical body is suppressed by reducing the distance between the pressurized peripheral surface and the held member on the bent distal end side. A caulking holding structure characterized by that. The caulking holding structure according to claim 3, wherein the pressure peripheral surface of the roller has a shape in which a peripheral diameter gradually increases on the bending tip side, so that the pressure peripheral surface of the roller and the held member are A caulking holding structure characterized by realizing a state in which the interval is reduced at the bent end side. 5. The caulking holding structure according to claim 4, wherein the pressure peripheral surface is a conical surface. 6. The caulking holding structure according to claim 5, wherein the angle of the conical surface is 5 ° or less and greater than 0 ° with respect to the axial direction of the roller. 6. The caulking holding structure according to claim 5, wherein an angle of the conical surface is formed in an angle range of 2 ° to 5 ° with respect to an axial direction of the roller. 4. The caulking holding structure according to claim 3, wherein an end surface of the held member is in a state of being close to the pressing peripheral surface on the bending tip side, so that the pressing peripheral surface of the roller and the held member are held. A caulking holding structure characterized by realizing a state in which a space between the member and the member is reduced at the leading end side. 9. The caulking holding structure according to claim 8, wherein an end surface of the held member has a shape having a step which becomes higher on the bent leading end side, whereby an interval between the pressure peripheral surface of the roller and the held member is increased. A caulking holding structure characterized by realizing a small state at the bent tip side. The caulking holding structure according to any one of claims 1 to 9, wherein the held member is a bearing, and the cylindrical body houses a rotating member arranged rotatably by the bearing, Or the caulking holding structure characterized by being a bearing holder arrange | positioned in this housing. 11. The caulking holding structure according to claim 10, wherein the bearing and the housing or the bearing holder are a bearing and a housing or a bearing holder in a rotation-linear motion conversion actuator, and the rotation-linear motion conversion actuator is a device to be driven. A rotating member is disposed in the housing or the bearing holder attached to the housing so as to be rotatable via the bearing, and an output shaft that moves in the axial direction of the cylinder by the rotation of the rotating member is protruded to the outside from the housing. A caulking holding structure that is arranged in a state and transmits a driving force from the output shaft to the device to be driven. 12. The caulking holding structure according to claim 11, wherein the rotating member is a nut of a planetary differential screw type rotation-linear motion conversion mechanism, the output shaft is a sunshaft, and a planetar is provided between the nut and the sunshaft. The caulking holding structure is characterized in that rotation-linear motion conversion is performed by a meshing mechanism between the sun shaft, the planetary shaft, and the nut formed in the nut by arranging a reshaft. The caulking holding structure according to claim 11 or 12, wherein the drive target device is an internal combustion engine. The held member is inserted and arranged up to the abutting surface installed inside the cylinder, and the end of the cylinder is bent by caulking to form a caulking portion. The caulking portion and the abutting surface form the held member. Is a caulking holding method for holding in the cylinder body in the axial direction of the cylinder,
A caulking holding method characterized by suppressing plastic flow toward the tip end side of the cylindrical body during caulking. The caulking and holding method according to claim 14, wherein the plastic flow toward the end tip side is suppressed by suppressing the end of the cylindrical body from extending toward the end tip side during the caulking process. A characteristic caulking retention method. 16. The caulking and holding method according to claim 14 or 15, wherein the cylindrical body is cylindrical, and the caulking process is caulking with a roller, and the roller pressurizes by bending an end of the cylindrical body. A peripheral surface and a support surface for preventing tilting of the region adjacent to the region that is bent at the end of the cylindrical body adjacent to the pressure peripheral surface. A caulking holding method characterized in that the plastic flow to the end tip side is suppressed by reducing the distance between the holding member and the holding tip side. The caulking and holding method according to claim 16, wherein the roller has a pressure peripheral surface having a shape in which a circumferential diameter is gradually increased on the bent tip side. The caulking and holding method according to claim 17, wherein the pressure peripheral surface is a conical surface. The caulking and holding method according to claim 18, wherein an angle of the conical surface is formed at an angle of 5 ° or less and greater than 0 ° with respect to an axial direction of the roller. The caulking and holding method according to claim 18, wherein the angle of the conical surface is formed in an angle range of 2 ° to 5 ° with respect to the axial direction of the roller. 17. The caulking holding method according to claim 16, wherein the held member has an end surface having a shape close to the pressing peripheral surface on the bent leading end side, whereby the pressing peripheral surface of the roller is provided. A caulking and holding method, wherein the distance between the holding member and the member to be held is reduced on the bent tip side. 22. The caulking and holding method according to claim 21, wherein the held member has an end surface formed with a step which becomes higher on the bending tip side, so that the pressing peripheral surface with respect to the pressure peripheral surface is formed. A caulking holding method characterized by using an end face having a close shape. The caulking and holding method according to any one of claims 14 to 22, wherein the held member is a bearing, and the cylindrical body houses therein a rotating member that is rotatably arranged by the bearing, Or it is a bearing holder arrange | positioned in this housing, The crimping holding method characterized by the above-mentioned. 24. The caulking and holding method according to claim 23, wherein the bearing and the housing or the bearing holder are a bearing and a housing or a bearing holder in a rotation-linear motion conversion actuator, and the rotation-linear motion conversion actuator is a device to be driven. A rotating member is disposed in the housing or the bearing holder attached to the housing so as to be rotatable through the bearing, and an output shaft that moves in the axial direction of the cylinder by the rotation of the rotating member is protruded to the outside from the housing. A caulking and holding method characterized by being arranged in a state and transmitting a driving force from the output shaft to the device to be driven. 25. The caulking and holding method according to claim 24, wherein the rotating member is a nut of a planetary differential screw type rotation-linear motion conversion mechanism, the output shaft is a sun shaft, and a planetar is provided between the nut and the sun shaft. A caulking and holding method characterized in that rotation-linear motion conversion is performed by a meshing mechanism between the sun shaft, the planetary shaft, and the nut formed in the nut by arranging a reshaft. 26. The caulking and holding method according to claim 24 or 25, wherein the drive target device is an internal combustion engine. By crimping the end of the cylindrical tubular body to form a caulking portion, the held member is clamped in the axial direction of the tubular body by the abutment surface installed inside the tubular body and the caulking portion. A roller used for processing,
The roller supports a pressure peripheral surface that bends and presses an end portion of the cylindrical body and a tilt that is adjacent to the pressure peripheral surface and an area adjacent to the region that is bent at the end of the cylindrical body. A caulking roller, wherein the pressure peripheral surface is a conical surface, and the pressure peripheral surface is bent and brought close to the held member on the leading end side. 28. The caulking roller according to claim 27, wherein an angle of the conical surface is 5 ° or less and greater than 0 ° with respect to an axial direction of the roller. 28. The caulking roller according to claim 27, wherein the angle of the conical surface is an angle in the range of 2 [deg.] To 5 [deg.] With respect to the axial direction of the roller. A caulking portion is formed by pressurizing and bending the end of the cylindrical body in a direction perpendicular to the axis of the caulking roller, comprising the caulking roller according to any one of claims 27 to 29. A caulking machine characterized by

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