JP6122622B2 - Cylinder device - Google Patents

Description

  The present invention relates to a cylinder device.

  Some metal cylinder devices are provided with an attachment eye at an end portion in the axial direction, and a bush is provided inside the attachment eye, and is attached to an attachment object via the bush (for example, Patent Documents). 1).

JP 2011-214587 A

  By the way, in the cylinder device having this structure, it is desired to prevent the bush from coming off from the mounting eye.

  Therefore, an object of the present invention is to provide a cylinder device capable of suppressing the slipping of the bush from the mounting eye.

To achieve the above object, the present invention is, unpainted portion is provided in the axially intermediate portion of the inner peripheral surface of the mounting eye, painted portion is provided in the axial direction end sides of the inner peripheral surface of the mounting eye In the state where the bush is press-fitted, the non-painted portion is not exposed to the outside, and the non-painted portion increases the removal load of the bush from the mounting eye .

  According to the present invention, it is possible to prevent the bush from coming off from the mounting eye.

It is a front view which shows the cylinder apparatus which concerns on one Embodiment of this invention. It is side sectional drawing which shows the attachment eye and rubber bush of the cylinder apparatus which concern on one Embodiment of this invention. It is process drawing of the manufacturing process of the cylinder apparatus which concerns on one Embodiment of this invention. It is a sectional side view which shows the masking jig used at the time of the coating of the cylinder apparatus which concerns on one Embodiment of this invention. It is a sectional side view which shows the state which mounted | wore the mounting eye of the cylinder apparatus which concerns on one Embodiment of this invention with the masking jig | tool.

  A cylinder device according to an embodiment of the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, a cylinder device 11 according to the present embodiment includes a substantially cylindrical cylinder 12 in which a liquid or gas as a fluid is sealed, and a cylinder 12 that is disposed on the central axis of the cylinder 12. A piston rod 13 projecting outward from an unillustrated opening at one end in the axial direction; a covered cylindrical cover 14 fixed to the external projecting portion of the piston rod 13 and covering the unillustrated opening side of the cylinder 12; have.

  A piston 15 is fixed to one end of the piston rod 13 disposed in the cylinder 12, and the piston 15 partitions the cylinder 12 into two chambers. The piston 15 slides inside the cylinder 12 integrally with the movement of the piston rod 13 to change the volume of the two chambers, and generates a damping force by the fluid flow resistance generated at that time. Specifically, the cylinder device 11 serves as a shock absorber that constitutes a vehicle suspension device. When the vehicle body side and the wheel side of the vehicle relatively vibrate, the piston rod 13 has a protrusion length with respect to the cylinder 12. As a result, the piston 15 fixed to the piston rod 13 slides inside the cylinder 12 to change the volume of the two chambers. To generate damping force. These cylinder 12, piston rod 13, cover 14, and piston 15 constitute a cylinder device body 20.

  A metal cylindrical mounting eye 21 is integrally provided at the end of the piston rod 13 on the protruding tip side, which is one end in the axial direction of the cylinder device body 20. Also, a metal cylindrical mounting eye 21 is integrally provided at the end of the cylinder device body 20 opposite to the protruding side of the piston rod 13 of the cylinder 12 which is the other end in the axial direction. It has been. Specifically, the mounting eye 21 is made of a carbon steel pipe for machine structure. One mounting eye 21 is fixed to the piston rod 13 and the cover 14 by welding, and the other mounting eye 21 is fixed to the cylinder 12 by welding. Has been.

  A rubber bush (bush) 22 is provided inside each of the mounting eyes 21. The rubber bush 22 is fitted to the mounting eye 21.

  For example, the cylinder device 11 is attached to the vehicle body side via a mounting member (not shown) through which a piston rod 13 is inserted into a rubber bush 22 in a mounting eye 21 fixed to the piston rod 13. It is attached to the wheel side through an attachment member (not shown) inserted through the rubber bush 22 in the attachment eye 21 fixed to the wheel. Thereby, the cylinder apparatus 11 attenuates the stroke with respect to the vehicle body of a wheel. In contrast to the above, the cylinder 12 may be attached to the vehicle body side and the piston rod 13 may be attached to the wheel side. In the present embodiment, the mounting eye 21 is integrally provided on both the piston rod 13 and the cylinder 12, that is, on both ends in the axial direction of the cylinder device body 20, but is integrally formed only on one of the ends. May be provided.

  The mounting eyes 21 on both sides have a cylindrical shape and are fixed to the corresponding ones of the piston rod 13 and the cylinder 12 on the outer peripheral surface 25, respectively, and the rubber bush 22 is fitted on the inner peripheral surface 26. The mounting eye 21 has its central axis orthogonal to the axial direction of the cylinder device main body 20, and is arranged so that the central position in the axial direction passes through the central axis of the cylinder device main body 20. Here, the mounting eyes 21 on both sides are common parts, and the rubber bushes 22 on both sides are also common parts.

  As shown in FIG. 2, the outer peripheral surface 25 of the mounting eye 21 has a cylindrical surface 31 at the middle portion in the axial direction, and both end portions in the axial direction become tapered surfaces 32 having a smaller diameter toward the end side. ing. The inner peripheral surface 26 of the mounting eye 21 is a cylindrical surface 35 at the axial intermediate portion, and both end portions in the axial direction are tapered surfaces 36 having a larger diameter toward the end side. The end surfaces 37 on both sides of the mounting eye 21 are flat surfaces along the direction perpendicular to the axis.

  The rubber bush 22 includes a resin-made cylindrical rubber 41 and a metal attachment tube body 42 that is integrally fixed to the central portion of the rubber 41 so as to penetrate the rubber 41. The attachment tube body 42 has a cylindrical shape. The rubber 41 is specifically made of natural rubber, and is fixed to the outer peripheral surface of the intermediate predetermined range in the axial direction of the mounting tube 42.

  Such a rubber bush 22 is fitted inside the mounting eye 21 in the rubber 41. At this time, the rubber 41 is elastically deformed and the inner peripheral surface of the mounting eye 21 is formed on the cylindrical outer peripheral surface 45 thereof. The surface 26 comes into close contact with the cylindrical surface 35 and comes into surface contact. As a result, the rubber bushing 22 is suppressed from being pulled out by the frictional resistance between the outer peripheral surface 45 of the rubber 41 and the cylindrical surface 35 of the mounting eye 21 generated by the elastic force of the rubber 41. The rubber bush 22 is fitted inside the mounting eye 21, and the central axis of the mounting tube 42 coincides with the central axis of the mounting eye 21. The rubber bush 22 is made of rubber, that is, a resin, in a portion that contacts the inner peripheral surface 26 of the mounting eye 21.

  Next, the manufacturing process of said cylinder apparatus 11 is demonstrated.

  As shown in the process diagram of FIG. 3, first, a body assembly process S1 for assembling the cylinder device body 20 shown in FIG. 1 is performed. At the completion of the main body assembly step S1, the mounting eye 21 is fixed to the cylinder 12 and the piston rod 13 of the cylinder device main body 20, respectively.

  Next, a masking step S2 shown in FIG. 3 for masking the inner peripheral surface 26 of the mounting eye 21 attached to the cylinder 12 and the piston rod 13 is performed.

  Here, a resin masking jig 51 shown in FIG. 4 is used. The masking jig 51 is made of synthetic rubber, specifically silicon rubber, and has a hollow cylindrical shape with both axial ends open. The masking jig 51 has a cylindrical inner peripheral surface 52 having a constant diameter and a stepped outer peripheral surface 53.

  The outer peripheral surface 53 includes, in order from one end side in the axial direction, one end tapered surface 55 having a larger diameter toward the other end side in the axial direction, a fitting cylindrical surface 56 having a constant diameter connected to the one end tapered surface 55, and the fitting cylindrical surface 56. An intermediate tapered surface 57 that is connected and has a smaller diameter toward the other axial end side, a cylindrical surface 58 having a constant diameter that is connected to the intermediate tapered surface 57, and an intermediate tapered surface that is connected to the cylindrical surface 58 and has a larger diameter toward the other axial end side. 59, a fixed diameter fitting cylindrical surface 60 connected to the intermediate tapered surface 59, an intermediate tapered surface 61 connected to the fitting cylindrical surface 60 and having a larger diameter toward the other axial end, and a constant connected to the intermediate tapered surface 61. The gripping cylindrical surface 62 has a diameter, and the other end tapered surface 63 is connected to the gripping cylindrical surface 62 and has a smaller diameter toward the other end in the axial direction.

  The fitting cylindrical surface 56 and the fitting cylindrical surface 60 have the same diameter, and these diameters are larger than the inner diameter of the cylindrical surface 35 of the inner peripheral surface 26 of the mounting eye 21 shown in FIG. Large diameter. The distance between the end of the fitting cylindrical surface 56 opposite to the fitting cylindrical surface 60 and the end of the fitting cylindrical surface 60 opposite to the fitting cylindrical surface 56 is within the mounting eye 21. The circumferential surface 26 is slightly longer than the axial length of the cylindrical surface 35. The minimum diameter of the one end tapered surface 55 is smaller than the maximum diameter of the tapered surface 36 of the inner peripheral surface 26 of the mounting eye 21, and smaller than the inner diameter of the cylindrical surface 35.

  The above-described masking jig 51 is fitted to the inner peripheral surface 26 of the mounting eye 21 attached to the cylinder 12 and the piston rod 13 with one end tapered surface 55 at the top while being held by the holding cylindrical surface 62. It will be. At this time, since the masking jig 51 has a hollow cylindrical shape, the deformation in the radial direction is relatively easy, and the fitting operation can be facilitated.

  During the above fitting, the masking jig 51 causes the fitting cylindrical surface 56 and the fitting cylindrical surface 60 to slide on the cylindrical surface 35 of the inner peripheral surface 26. The cylindrical surface 56 and the fitting cylindrical surface 60 are fitted into the cylindrical surface 35 of the inner peripheral surface 26 with a margin. The axial position of the masking jig 51 is adjusted such that the intermediate taper surface 61 faces one of the taper surfaces 36 of the mounting eye 21 and forms a predetermined gap with the taper surface 36. Then, in the masking jig 51, the fitting cylindrical surface 56, the intermediate tapered surface 57, the cylindrical surface 58, the intermediate tapered surface 59, and the fitting cylindrical surface 60 cover the entire cylindrical surface 35 of the inner peripheral surface 26 of the mounting eye 21. It will cover and will be in the state spaced apart from the taper surface 36 of the both sides of the inner peripheral surface 26 of the attachment eye 21. FIG. That is, the masking jig 51 masks only the cylindrical surface 35 without masking the tapered surfaces 36 on both sides of the inner peripheral surface 26 of the mounting eye 21. The intermediate taper surface 57, the cylindrical surface 58 and the intermediate taper surface 59 form an annular retraction groove 64 that is recessed in the radial direction in the masking jig 51, and the retraction groove 64 is attached to the masking jig 51. Since the contact area at the time of fitting to the eye 21 is reduced, the sliding resistance is reduced, and the fitting work of the masking jig 51 to the mounting eye 21 can be facilitated.

  Next, the painting step S3 shown in FIG. In this coating step S3, electrodeposition coating is performed, and specifically, cationic electrodeposition coating is performed. Thereby, the surfaces of the cylinder device main body 20 and the attachment eyes 21 on both sides attached thereto are painted except for the portions masked by the masking jigs 51 on both sides. In addition, you may make it paint by other systems, such as electrostatic coating instead of cationic electrodeposition coating.

  And the masking cancellation | release process S4 shown in FIG. 3 from which the masking jig | tool 51 is each removed from the attachment eye 21 of both sides is performed. In this masking release process, the masking jig 51 is pulled out from the mounting eye 21 while being gripped by the gripping cylindrical surface 62. The attachment eyes 21 attached to the cylinder 12 and the piston rod 13 respectively have the tapered surfaces 36 on both sides of the inner peripheral surface 26, the end surfaces 37 on both sides, and the cylinders on the outer peripheral surface 25 with the masking jig 51 removed. 12 or a portion excluding the joint portion to the piston rod 13 is a painted portion A to which coating has been applied. Further, the cylindrical surface 35 of the inner peripheral surface 26 becomes a non-painted portion B that is not painted and has a higher friction coefficient than the painted portion A. In particular, since cationic electrodeposition coating is performed as the coating, the friction coefficient of the non-painted portion B is significantly higher than the friction coefficient of the painted portion A. The masking jig 51 is used repeatedly.

  Next, the bush mounting step S5 shown in FIG. 3 for fitting the rubber bush 22 to each of the mounting eyes 21 on both sides is performed. As a result, as shown in FIG. 2, the rubber bush 22 is brought into a state of being in surface contact with the cylindrical surface 35 of the mounting eye 21 on the outer peripheral surface 45 of the rubber 41 while elastically deforming the rubber 41, and the rubber 41 generated by the elastic force of the rubber 41. The mounting eye 21 is held by the frictional force between the outer peripheral surface 45 and the cylindrical surface 35 of the mounting eye 21. Here, since the entire cylindrical surface 35 of the mounting eye 21 is the non-painted portion B, the rubber bush 22 comes into contact with only the non-painted portion B with respect to the mounting eye 21. In this embodiment, the coating step S3 is performed after the main body assembly step S1, but the mounting eye 21 is fixed to the piston rod 13 and the cover 14 or the cylinder 12 by welding after the masking step and the coating step. It may be.

  According to the cylinder device 11 of the present embodiment described above, the cylinder device main body 20 and the mounting eye 21 are painted in a state where the cylinder device main body 20 is provided with the mounting eye 21. By masking the cylindrical surface 35 of the inner peripheral surface 21 of 21, the cylindrical surface 35 becomes a non-coating portion B having a higher coefficient of friction than the coating portion A. Therefore, after that, the rubber bushing 22 held in surface contact with the cylindrical surface 35 of the mounting eye 21 on the outer peripheral surface 45 of the rubber 41 is a frictional force between the outer peripheral surface 45 of the rubber 41 and the cylindrical surface 35 of the mounting eye 21. Becomes higher. Therefore, the removal load necessary for the rubber bushing 22 to be removed from the mounting eye 21 is higher than that in the case where the cylindrical surface 35 is used as the coating portion, and the removal can be suppressed.

Further, the mounting eye 21 is coated with tapered surfaces 36 on both sides of the inner circumferential surface 26 in addition to the end surfaces 37 on both sides and the portion of the outer circumferential surface 25 excluding the portion joined to the cylinder 12 or the piston rod 13. Since it becomes the coating part A, it can suppress that an unpainted part stands out.
In particular, by preventing only the painted tapered surface 36 from being exposed and not exposing the non-painted portion B by the resin (rubber) rubber bush 22, the water or the like is less likely to adhere to the non-painted portion B. It becomes possible to suppress the occurrence of rust. Therefore, it is desirable to make the coating portion A a little inside the tapered surface 36.

  Further, since the cylinder device body 20 and the mounting eye 21 are painted by cationic electrodeposition coating, the difference in the friction coefficient between the painted portion A and the non-painted portion B becomes large. Therefore, the unloading load necessary for the rubber bushing 22 to be detached from the mounting eye 21 is higher than that in the case where the rubber bush 22 is used as the painted portion, and the unplugging can be further suppressed. Specifically, the unloading load of the present embodiment in which the cylindrical surface 35 of the mounting eye 21 is not painted is about twice as high as the unloading load when the cylindrical surface 35 of the mounting eye 21 is painted.

  Further, since the rubber bushing 22 that has a possibility of coming off from the mounting eye 21 is used as the portion that contacts the inner peripheral surface 26 of the mounting eye 21, it is effective to suppress the removal by increasing the friction coefficient. .

  In addition, since the masking jig 51 has a hollow cylindrical shape, attachment and removal to and from the attachment eye 21 are facilitated. Therefore, the workability of the masking work can be improved.

  Further, since the retraction groove 64 is formed in the fitting portion of the masking jig 51 to the mounting eye 21, the sliding resistance of the masking jig 51 with respect to the mounting eye 21 can be reduced. Therefore, the workability of the masking work can be improved.

  The present embodiment is a cylinder having a cylinder device main body, a cylindrical mounting eye provided integrally with at least one end of the cylinder device main body in the axial direction, and a bush provided inside the mounting eye. A device is characterized in that, among the cylinder device main body and the mounting eye, at least an inner peripheral surface of the mounting eye is provided with a non-coating portion, and other portions are painted. Thereby, compared with the case where the inner peripheral surface of the mounting eye is used as the coating portion, the removal load necessary for the bushing to be detached from the mounting eye is increased, and the removal can be suppressed.

  In addition, since the coating is a cationic electrodeposition coating, the difference in the coefficient of friction between the painted portion and the non-painted portion increases, so that the unloading load necessary for the bushing to come off from the mounting eye becomes the painted portion. It becomes higher than the case, and the omission can be further suppressed.

  Moreover, since the part which contacts the inner peripheral surface of the said attachment eye is resin, the suppression of the omission by raising a friction coefficient becomes effective.

  Further, the non-coating portion is provided in an intermediate portion in the axial direction of the mounting eye, and both end sides in the axial direction of the inner peripheral surface of the mounting eye are coating portions, and the non-coating portion is in a state where the bush is press-fitted. The painted part is not exposed to the outside. Thereby, generation | occurrence | production of rust can be suppressed.

  In the above-described embodiment, the cylinder device is described as an example of a hydraulic pressure (pneumatic pressure, hydraulic pressure) shock absorber used in an automobile suspension. However, the present invention is not limited to this, and vibration suppression for automobiles, washing machines, and buildings is used. The present invention may be applied to a hydraulic shock absorber or a friction damper used in the apparatus.

11 Cylinder device 20 Cylinder device body 21 Mounting eye 22 Rubber bush (bush)
26 Inner peripheral surface 35 Cylindrical surface 36 Tapered surface 37 End surface 51 Masking jig A Painted part B Non-painted part

Claims (3)

A cylinder device body;
A cylindrical mounting eye provided integrally with at least one end of the cylinder device body in the axial direction;
A cylinder device having a bush provided inside the mounting eye,
Among the cylinder device body and the attachment eye, before SL in the axial intermediate portion of the inner peripheral surface of the mounting eye unpainted portion is provided, the coating unit is provided in the axial direction end sides of the inner peripheral surface of the mounting eye The cylinder device is characterized in that the non-painted portion is not exposed to the outside in a state in which the bush is press-fitted, and the non-painted portion increases the removal load of the bush from the mounting eye. .   The cylinder device according to claim 1, wherein the coating is cationic electrodeposition coating.   The cylinder device according to claim 1, wherein the bush is made of resin at a portion that contacts the inner peripheral surface of the mounting eye.

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