Buffer device and suspension device

Abstract

To provide a buffer device or the like which is suppressed from damaging the appearance in comparison with a case where a cylinder part and an exterior body are welded from the outside by arc welding.SOLUTION: A buffer device is provided with a cylinder part for storing a working fluid and an exterior body into which the cylinder part is inserted in the center line direction of the cylinder part, wherein the exterior body has a cylindrical part to be inserted into which the cylinder part is inserted and a residual part which is a residue excluding the part to be inserted in the center line direction, and the cylinder part and the exterior body are welded by irradiating the exterior body with a beam from the direction in which the cylinder part is positioned at the boundary between the part to be inserted and the residual part.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to shock absorbers and suspension systems. [Background technology]

[0002] For example, Patent Document 1 describes the structure of the wheel-side mounting part of a strut in a strut-type suspension system, in which only the upper end of a cylindrical locking member having a predetermined axial length is welded to the strut outer tube, the wheel-side connecting part of the strut outer tube is inserted and passed through a through hole provided in the strut connecting part of the knuckle, and a nut is screwed and fastened to the male threaded portion formed on the wheel-side connecting part of the strut outer tube that protrudes downward, thereby connecting and fixing the strut connecting part of the knuckle between the nut and the lower end face of the locking member in an axially fixed state. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-263110 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, if the cylinder portion of the shock absorber and the exterior body into which the cylinder portion is inserted are welded by arc welding from the outside of the exterior body, such as the strut outer tube and locking member in Patent Document 1, the welded portion will be exposed to the outside, marring the aesthetic appearance of the shock absorber. The present invention provides a shock absorber etc. in which the aesthetic appearance is less impaired than when the cylinder portion and the exterior body are welded by arc welding from the outside of the exterior body. [Means for solving the problem]

[0005] The present invention, which was completed with this objective in mind, is a shock absorber comprising a cylinder portion that contains a working fluid, and an outer body into which the cylinder portion is inserted in the center line direction of the cylinder portion, wherein the outer body has a cylindrical inserted portion into which the cylinder portion is inserted, and a remaining portion in the center line direction that is the remainder excluding the inserted portion, and the cylinder portion and the outer body are welded at the boundary between the inserted portion and the remaining portion by irradiating a beam from the direction in which the cylinder portion is located relative to the outer body. Effect of the Invention

[0006] According to the present invention, it is possible to provide a shock absorber etc. in which the aesthetic appearance is less impaired than when the cylinder portion and the exterior body are welded from the outside by arc welding. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram showing a schematic configuration of a suspension system including a shock absorber to which a first embodiment is applied, attached to a wheel and a body of a vehicle. [Diagram 2] 1 is a diagram illustrating a schematic configuration of a shock absorber to which a first embodiment is applied; [Diagram 3] 10A and 10B are diagrams illustrating welding between a cylinder portion and an exterior body in a shock absorber. [Figure 4] 1A and 1B are diagrams for explaining the length of the shock absorber in the center line direction, where FIG. 1A explains the length required for the shock absorber in the center line direction, and FIG. 1B explains the extension of the shock absorber due to the attachment of an exterior body. [Diagram 5] FIG. 13 is a diagram illustrating a comparative example using arc welding. [Figure 6] 11 is a diagram showing a schematic configuration example of a shock absorber to which a second embodiment is applied; FIG. [Figure 7] FIG. 11 is a diagram showing a schematic configuration of a suspension system including a shock absorber to which a third embodiment is applied, attached to a wheel and a vehicle body. [Figure 8]11A and 11B are diagrams illustrating a schematic configuration of a shock absorber to which a third embodiment is applied, in which (a) is an enlarged view of the vicinity of an exterior body of the shock absorber, and (b) is an enlarged view of the shock absorber as viewed from the left side of the paper in (a). [Figure 9] 10A and 10B are diagrams for explaining the deployment of the remaining portion, in which (a) and (b) are diagrams for explaining an example of deploying the remaining portion in the radial direction, and (c) and (d) are diagrams for explaining an example of deploying the remaining portion in the center line direction. [Figure 10] 11A and 11B are diagrams illustrating other examples of use of the remaining portion, where (a) is a diagram showing an example of use in a stabilizer link, and (b) is a diagram showing an example of use in a bracket stopper. [Figure 11] 13A and 13B are diagrams illustrating a schematic configuration of a shock absorber to which a fifth embodiment is applied. [Figure 12] FIG. 11 is a diagram explaining the formation of a piston stopper in a shock absorber, where (a) is a diagram showing the process of welding an outer tube and an outer casing, and (b) to (d) are diagrams showing the process of forming the piston stopper by processing the outer casing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First Embodiment [Overall configuration of suspension system 100] FIG. 1 is a diagram showing a schematic configuration of a suspension device 100 equipped with a shock absorber 1 to which the first embodiment is applied, attached to a vehicle wheel 101 and a vehicle main body (sometimes called a "car body") 102 of the vehicle. FIG. 2 is a diagram illustrating a schematic configuration of a shock absorber 1 to which the first embodiment is applied. In the following description, the lower side in the direction of the center line (a dashed line indicated by the symbol C in the figures, which may be referred to as "center line C") of the shock absorber 1 shown in Figures 1 and 2 may be referred to as "one side," and the upper side in the figures may be referred to as "the other side." Also, the center in the radial direction of the shock absorber 1 (more specifically, the radial direction of a cylinder portion 10 described later) may be referred to as the "center side," and the outer side in the radial direction may be referred to as the "outer side."

[0009] The suspension device 100 is a so-called strut-type suspension, and as shown in Fig. 1, includes a shock absorber 1 having a cylinder portion 10, and a coil spring 103 arranged on the outside of the shock absorber 1. The suspension device 100 also includes a lower spring sheet 104 that supports one end of the coil spring 103 (the lower side in Fig. 1), and an upper spring sheet 105 that supports the other end of the coil spring 103 (the upper side in Fig. 1). The suspension device 100 also includes a lower sheet rubber 106 that is interposed between the lower end of the coil spring 103 and the lower spring sheet 104, and an upper sheet rubber 107 that is interposed between the upper end of the coil spring 103 and the upper spring sheet 105.

[0010] The suspension device 100 is attached to the other end of the rod 11 of the shock absorber 1, and includes a vehicle body side mounting portion 108 for mounting the suspension device 100 to a vehicle body 102. The suspension device 100 also includes a bracket portion 203 provided at one end of the shock absorber 1 for mounting the suspension device 100 to the wheel 101. More specifically, the bracket portion 203 is provided on an exterior body 20 of the shock absorber 1. The exterior body 20 will be described in detail later with reference to FIG. 2.

[0011] The suspension device 100 configured as described above is attached to the wheel 112 that holds the tire 111 of the wheel 101 via the bracket portion 203. More specifically, the suspension device 100 is connected to a knuckle 110 (an example of a connecting member) of the wheel 112 using the bracket portion 203. The bracket portion 203 is an example of a connecting member that connects the suspension device to the connecting member. The suspension device 100 is attached to the vehicle body 102 via a vehicle body side mounting portion 108.

[0012] [Configuration and function of shock absorber 1] 2, the shock absorber 1 includes a cylinder portion 10 that contains oil as an example of a working fluid, and a rod 11 that has one side that is slidably inserted into the cylinder portion 10 and the other side that is provided so as to protrude outside the cylinder portion 10. The shock absorber 1 also includes a piston that is provided at one end of the rod 11 inside the cylinder portion 10, a valve that is located at one end inside the cylinder portion 10, and the like (none of which are shown).

[0013] The shock absorber 1 has a plurality of oil flow paths inside the cylinder portion 10. More specifically, a plurality of flow paths are formed inside the cylinder portion 10 by the above-mentioned structures of the piston, valve, etc. In the shock absorber 1, when the rod 11 moves in the center line direction, the oil passes through the flow paths, thereby generating a damping force against the movement of the rod 11. This damping force allows the shock absorber 1 to achieve a function of mitigating the impact transmitted from the wheel 101 (see FIG. 1) to the vehicle body 102 (see FIG. 1), i.e., the shock absorber 1 achieves a function of cushioning.

[0014] 2, the shock absorber 1 includes an exterior body 20 into which a portion of one side of the cylinder portion 10 (the portion indicated by the dashed line in FIG. 2) is inserted. In other words, the exterior body 20 is provided at one end of the cylinder portion 10 so as to cover the radial outside. The exterior body 20 has a cylindrical inserted portion 201 into which the cylinder portion 10 is inserted (the radially central side), and a remaining portion 202 that is the remainder of the exterior body 20 in the center line direction after removing the inserted portion 201.

[0015] The inserted portion 201 has a tubular structure as a portion of the exterior body 20 into which the cylinder portion 10 is inserted. More specifically, the inserted portion 201 according to the first embodiment has a substantially cylindrical structure as a tubular structure into which the substantially cylindrical cylinder portion 10 is inserted. Note that, although an example in which the inserted portion 201 is configured to be shorter than the remaining portion 202 in the center line direction is shown here, the length of the inserted portion 201 is not limited. That is, the inserted portion 201 may be configured to be longer or shorter than that shown in the figure, and may be configured to have a length such that the entire cylinder portion 10 is inserted, or may be configured to be longer than the remaining portion 202.

[0016] The remaining portion 202 is a remainder obtained by excluding the inserted portion 201 from the entire length of the exterior body 20 in the center line direction. In other words, the remaining portion 202 is a portion of the exterior body 20 into which the cylinder portion 10 is not inserted. More specifically, the remaining portion 202 according to the first embodiment has a cylindrical portion having a structure in which the inserted portion 201 is extended by a length L1 (see FIG. 3) to one side in the center line direction, and one end of the remaining portion 202 does not have a bottom surface, but is surrounded by an edge 205 to form an opening that leads to the inside of the cylindrical portion. In addition, the remaining portion 202 has a structure in which the bracket portion 203 protrudes from the outer circumferential surface of the cylindrical portion toward the outside in the radial direction. The length of the remaining portion 202 in the center line direction is not limited, and may be configured to be longer or shorter than that shown in the figure.

[0017] The bracket portion 203 is an example of a connecting member that connects the suspension device 100 to the vehicle, and is provided to protrude from the outer circumferential surface of the remaining portion 202 of the exterior body 20 as described above. More specifically, the bracket portion 203 illustrated in FIG. 2 has a through hole 204 used for connection to the knuckle 110 (see FIG. 1). Then, the bracket portion 203 is connected to the knuckle 110 described above using a bolt or the like passed through the through hole 204. Note that the shape of the bracket portion 203, the protruding position and protruding direction in the remaining portion 202, the shape, arrangement, and number of the through holes 204, and the like are merely examples, and are not limited as long as they enable the suspension device 100 to be attached to the wheel 101. Moreover, the bracket portion 203 may have other structures for connection to a connecting member of the vehicle, such as a screw hole, a protrusion, or a groove, instead of or in addition to the through hole 204.

[0018] [Welding of the cylinder portion 10 and the exterior body 20] Here, in the shock absorber 1 to which the first embodiment is applied, the cylinder portion 10 and the exterior body 20 are welded by irradiating a beam from a direction in which the cylinder portion 10 is located relative to the exterior body 20 (the radial center side in FIG. 2). In the first embodiment and second to fifth embodiments described later, the "beam" irradiated during welding includes an electron beam and a laser beam. That is, the welding by beam irradiation used in each embodiment includes so-called electron beam welding and laser beam welding. The welding of the cylinder portion 10 and the exterior body 20 will be described in detail below.

[0019] Fig. 3 is a diagram for explaining welding between the cylinder portion 10 and the exterior body 20 in the shock absorber 1. Fig. 3 is an enlarged view of the area enclosed by the two-dot chain line in Fig. 2, and corresponds to a cross-sectional view of the shock absorber 1 cut along the center line C by a plane parallel to the paper surface. FIG. 4 is a diagram illustrating the length of the shock absorber 1 in the center line direction, where (a) is a diagram illustrating the length required for the shock absorber 1 in the center line direction, and (b) is a diagram illustrating the extension of the shock absorber 1 due to the attachment of the outer body 20. Fig. 5 is a diagram for explaining a comparative example using arc welding. Note that in Fig. 4 and Fig. 5, the bracket part 203 is omitted, and since it is a cross-sectional view in the center line direction, the schematic configuration of the rod 11 and the piston 12 in the cylinder part 10 is shown.

[0020] As shown in Fig. 3, the cylinder portion 10 and the exterior body 20 in the shock absorber 1 are welded and joined at a welded portion 200. More specifically, the welded portion 200 is formed at the boundary between an inserted portion 201 and a remaining portion 202 by fusion welding an end surface 122 on one side of the cylinder portion 10 and an inner circumferential surface 207 of the exterior body 20 together by irradiating a beam from a direction in which the cylinder portion 10 is located relative to the exterior body 20 (the radial center side in Fig. 3, as shown by the open arrow).

[0021] Incidentally, as shown in Fig. 4(a), in general, the shock absorber 1 needs to have a total length Lo in the center line direction (referred to as "required total length Lo") as the length required for mounting the shock absorber 1 on a vehicle. On the other hand, in order to achieve the shock absorber performance required for the shock absorber 1, it is sufficient that the cylinder portion 10 of the shock absorber 1 has a stroke Ls (referred to as "required stroke Ls") required for achieving the shock absorber performance.

[0022] Here, depending on the vehicle design, etc., there are cases where the required overall length Lo is longer than the required stroke Ls. In this case, for example, as shown by the dashed line in Fig. 4(a), a mode can be considered in which the overall length Lo required for the shock absorber 1 is ensured by extending the cylinder portion 10 itself to a length approximately equal to the required overall length Lo (extending by the difference between Lo-Ls). However, in such a mode, the cylinder portion 10 is configured to be longer than the required stroke Ls, and as a result of the increased volume of the cylinder portion 10, the amount of oil to be filled in the cylinder portion 10 increases, and the manufacturing cost of the shock absorber 1 increases.

[0023] 4(b), in the shock absorber 1 to which the first embodiment is applied, the total length Lo required by attaching the exterior body 20 is ensured as a mode different from the extension of the cylinder portion 10 itself. In this case, since it is not necessary to fill the portion extended by the exterior body 20, i.e., the remaining portion 202 of the exterior body 20, with oil, an increase in manufacturing costs is suppressed compared to the mode in which the cylinder portion 10 itself is extended. In addition, since it is possible to vary the total length of the shock absorber 1 by adjusting the length of the remaining portion 202 of the exterior body 20, shock absorbers 1 having various total lengths Lo can be manufactured using a common cylinder portion 10.

[0024] When the overall length Lo in the center line direction is ensured by the exterior body 20 as in the shock absorber 1, the cylinder portion 10 and the exterior body 20 need to be fixed by welding. Here, as shown in Fig. 5, a shock absorber 1' in which the cylinder portion 10 and the exterior body 20 are arc-welded will be considered as a comparative example to which the first embodiment is not applied. When welding the cylinder portion 10 and the exterior body 20 by arc welding, for example, as shown as position A in the figure, it is considered that a welding torch 90 is inserted into the inside of a cylindrical portion in the remaining portion 202 of the exterior body 20, and an end surface 122 on one side of the cylinder portion 10 and an inner circumferential surface 207 of the exterior body 20 are welded. However, inserting the torch 90 at position A may reduce the workability of the welding work and may lead to a decrease in the accuracy of the welding.

[0025] In particular, when length L1 of remaining portion 202 in the center line direction satisfies the following formula (1), angle θ between inner circumferential surface 207 of outer casing 20 and torch 90 (or angle between cylinder portion 10 and torch 90) exceeds 50 degrees. In arc welding, generally, the angle between the surface to be welded and the torch needs to be 40 degrees to 50 degrees, and welding outside this range becomes difficult. In other words, when length L1 of remaining portion 202 satisfies the following formula (1), welding from position A becomes difficult with arc welding.

[0026]

number

[0027] For the above reasons, in the shock absorber 1' of the comparative example, as shown as position B in the drawing, a torch 90 is applied from the outside in the radial direction of the exterior body 20 to weld the outer circumferential surface 121 on one side of the cylinder portion 10 to the edge 206 on the other side of the exterior body 20. As a result, the welded portion 200' is exposed to the outside of the shock absorber 1', which mars the aesthetic appearance of the shock absorber 1'.

[0028] In contrast to this comparative shock absorber 1', in the shock absorber 1 to which the first embodiment is applied, the welded portion 200 is not exposed to the outside (as described above with reference to FIG. 3), and therefore, the deterioration of the aesthetic appearance of the shock absorber 1 due to welding between the cylinder portion 10 and the exterior body 20 is suppressed. In particular, when the length L1 of the remaining portion 202 satisfies the formula (1), welding is difficult by arc welding, and therefore it is more preferable to use beam welding as in the first embodiment.

[0029] In the first embodiment, the bracket portion 203 may be provided in advance on the exterior body 20 before welding the cylinder portion 10 and the exterior body 20 together, or may be attached to the exterior body 20 after welding the cylinder portion 10 and the exterior body 20 together. In addition, an opening surrounded by edge 205 is formed at one end of exterior body 20, and a beam is irradiated from this opening to perform welding, but it is also possible to provide a bottom with a through hole (passage hole) and irradiate the beam from this through hole to perform welding.

[0030] <Second embodiment> Next, a second embodiment in which the required total length Lo is ensured by a structure different from the exterior body will be described with reference to Fig. 6. Note that the same names and symbols are used for parts similar to those of the first embodiment described above, and descriptions thereof may be omitted. Fig. 6 is a diagram showing a schematic configuration example of a shock absorber 2 to which the second embodiment is applied. Fig. 6 corresponds to a cross-sectional view of the shock absorber 2 in the center line direction.

[0031] As shown in the figure, the shock absorber 2 to which the second embodiment is applied includes a cylindrical outer cylinder 30 (an example of a cylindrical member) and an inner body 15 (an example of a partition member) that partitions the inside of the outer cylinder 30. More specifically, the inner body 15 partitions the inside of the outer cylinder 30 into a storage section 301 that stores oil and a remaining section 302 that is a remainder in the center line direction when the storage section 301 is removed. Inside the storage section 301 (inside in the radial direction), there are provided a cylindrical inner cylinder 13, a rod 11 and a piston 12 that are disposed inside the inner cylinder 13, and a bottom section 14 that is disposed on one side of the inner cylinder 13, which constitute a cylinder section and ensure the shock absorber function of the shock absorber 2.

[0032] Here, in the shock absorber 2 to which the second embodiment is applied, the outer cylinder 30 and the inner body 15 are joined by beam welding at the welded portion 300. More specifically, the welded portion 300 is formed by fusion welding the inner circumferential surface 307 of the outer cylinder 30 and the surface 151 on one side of the inner body 15 by irradiating a beam from the direction in which the inner body 15 is located relative to the outer cylinder 30 (the radial center side in FIG. 6, shown by the open arrow). That is, in the shock absorber 2, as in the shock absorber 1 to which the first embodiment is applied, the welded portion 300 is not exposed to the outside, so that the deterioration of the appearance due to welding is suppressed. In addition, by adjusting the length L2 of the remaining portion 302 in the center line direction, the total length Lo required for the shock absorber 2 can be ensured.

[0033] Here, in the shock absorber 2, when the length L2 of the remaining portion 302 satisfies the following formula (2), the angle between the inner circumferential surface 307 of the outer cylinder 30 and the torch 90 (described above with reference to FIG. 5) (or the angle between the surface 151 of the inner body 15 and the torch 90) exceeds 50 degrees, making it difficult to perform arc welding. In other words, when the length L2 of the remaining portion 302 satisfies formula (2), welding is difficult by arc welding, so it is more preferable to use beam welding as in the second embodiment.

[0034]

number

[0035] 6, the shock absorber 2 may include a bracket portion 203 (see FIG. 1) similar to that of the shock absorber 1. The bracket portion 203 of the shock absorber 2 may be provided on the outer cylinder 30 in advance before welding the outer cylinder 30 and the inner body 15 together, or may be attached to the outer cylinder 30 after welding the outer cylinder 30 and the inner body 15 together. In addition, an opening surrounded by an edge 305 is formed at one end of the outer tube 30, and a beam may be irradiated from this opening to perform welding, or a bottom with a through hole (passage hole) may be provided, and a beam may be irradiated from this through hole to perform welding.

[0036] <Third embodiment> In the above-described first embodiment, an example has been described in which a bracket portion 203 for attaching the strut-type suspension device 100 to the wheel 101 is provided in the remaining portion 202 of the shock absorber 1. The third embodiment differs from the first embodiment in that a joint portion is provided instead of the bracket portion 203. Hereinafter, the third embodiment will be described with reference to Figs. 7 and 8, but in the third embodiment, portions similar to those in the first embodiment will be given the same names and reference numerals and descriptions thereof may be omitted. FIG. 7 is a diagram showing a schematic configuration of a suspension device 100' including a shock absorber 3 to which the third embodiment is applied, attached to a wheel 101 and a vehicle body 102. As shown in FIG. FIG. 8 is a diagram illustrating the schematic configuration of a shock absorber 3 to which the third embodiment is applied, where (a) is an enlarged view of the vicinity of the outer casing 20′ in the shock absorber 3, and (b) is an enlarged view of the shock absorber 3 as viewed from the left side of the page in (a).

[0037] The suspension 100' is a so-called double wishbone suspension, and as shown in Fig. 7, is equipped with a shock absorber 3 having a cylinder portion 10, and a coil spring 103 arranged on the outside of the shock absorber 3. Similarly to the suspension 100 described using Fig. 1, the suspension 100' is equipped with a lower spring sheet 104, an upper spring sheet 105, a lower seat rubber 106, and an upper seat rubber 107.

[0038] The suspension device 100' is attached to the other end of the rod 11 of the shock absorber 3, and includes a vehicle body side mounting portion 108 for mounting the suspension device 100' to the vehicle body 102. The suspension device 100' is also provided at one end of the shock absorber 3, and includes a joint portion 209 for connecting the suspension device 100' to the wheel 101. More specifically, the joint portion 209 is provided on an exterior body 20' of the shock absorber 3. The exterior body 20' will be described in detail with reference to FIG. 8.

[0039] The suspension device 100' configured as described above is attached to the wheel 112 that holds the tire 111 of the wheel 101 via a joint portion 209. More specifically, the suspension device 100' is connected to the lower arm 114 (an example of a connecting member) of the upper arm 113 and the lower arm 114 that extend from the knuckle 110 of the wheel 112, using the joint portion 209. The joint portion 209 is an example of a connecting member that connects the suspension device to the connecting member. The suspension device 100' is attached to the vehicle body 102 via a vehicle body side mounting portion 108.

[0040] As shown in Figs. 8(a) and (b), the shock absorber 3 includes an exterior body 20' into which a portion of one side of the cylinder section 10 (the portion indicated by the dashed line in Fig. 8) is inserted. In other words, the exterior body 20' is provided at one end of the cylinder section 10 so as to cover the outside in the radial direction. Similarly to the exterior body 20 in the first embodiment, the exterior body 20' includes a cylindrical inserted portion 201' into which the cylinder section 10 is inserted (the center side in the radial direction), and a remaining portion 202' which is the remainder obtained by removing the inserted portion 201' from the exterior body 20' in the center line direction. The remaining portion 202' in the shock absorber 3 includes a joint portion 209 provided at one end instead of the bracket portion 203 in the shock absorber 1.

[0041] The joint 209 is an example of a connecting member that connects the suspension 100 to the vehicle, and is provided at one end of the remaining portion 202' of the exterior body 20' as described above. More specifically, the joint 209 illustrated in FIG. 8 has a through hole 210 used for connection to the lower arm 114. Then, the joint 209 is connected to the lower arm 114 by passing a shaft portion provided in the lower arm 114 through the through hole 210. Note that the shape of the joint 209, the protruding position and protruding direction in the remaining portion 202', the shape, arrangement, and number of the through holes 210 are merely examples, and are not limited as long as they enable the suspension 100' to be attached to the wheel 101. The joint 209 may have another structure for connection to the lower arm 114. Additionally, the shock absorber 3 may include a rib portion 208 that reduces the rigidity of the joint portion 209 in the circumferential direction (the circumferential direction of the shaft portion of the lower arm 114).

[0042] In this shock absorber 3, similarly to the shock absorber 1, the cylinder portion 10 and the exterior body 20' are beam-welded together by irradiating a beam from a direction in which the cylinder portion 10 is located relative to the exterior body 20', thereby preventing damage to the appearance of the shock absorber 3. In the third embodiment, the joint portion 209 may be provided in advance on the exterior body 20' before welding the cylinder portion 10 and the exterior body 20' together, or may be attached to the exterior body 20' after welding the cylinder portion 10 and the exterior body 20' together.

[0043] In the third embodiment, an example has been described in which the bracket portion 203 in the shock absorber 1 (see FIG. 3) is replaced with the joint portion 209 to apply the shock absorber 3 to the double wishbone suspension 100', but the bracket portion 203 in the second embodiment may be replaced with the joint portion 209. In other words, the shock absorber 2 (see FIG. 6) may be provided with a rib portion 208 or a joint portion 209 on the outer cylinder 30 to be applied to the double wishbone suspension 100'.

[0044] <Fourth embodiment> In the first to third embodiments described above, examples have been described in which the cylinder portion 10 and the inner body 15 are welded to the outer body 20, 20' or the outer tube 30 on which the bracket portion 203 and the joint portion 209 are provided in advance, and examples in which the bracket portion 203 and the joint portion 209 are attached to the outer body 20, 20' or the outer tube 30 after welding. In the fourth embodiment, after welding the outer body and the cylinder portion, or the outer tube and the inner body, the remaining cylindrical portion is cut open (sometimes referred to as "unfolding") to form the bracket portion, the joint portion, and also the stays and bracket stoppers described below. Hereinafter, the fourth embodiment will be described in detail with reference to Figures 9 and 10. In the fourth embodiment, parts similar to those in the first embodiment described above may be given the same names and symbols and descriptions thereof may be omitted.

[0045] 9A and 9B are diagrams for explaining the deployment of the remaining portion 242, where (a) and (b) are diagrams for explaining an example of deploying the remaining portion 242 in the radial direction, and (c) and (d) are diagrams for explaining an example of deploying the remaining portion 242 in the center line direction. 10A and 10B are diagrams illustrating other examples of use of the remaining portion 242 (see FIG. 9), where (a) is a diagram showing an example of use in a stabilizer link 70, and (b) is a diagram showing an example of use in a bracket stopper 80.

[0046] As shown in Figures 9(a) and (c), the shock absorber 4 to which the fourth embodiment is applied has, for example, substantially the same structure as the shock absorber 1 to which the first embodiment is applied. More specifically, the shock absorber 4 includes a cylinder portion 10 and an exterior body 20'', and the exterior body 20'' has an inserted portion 241 and a remaining portion 242. Furthermore, the cylinder portion 10 and the exterior body 20'' are beam welded by irradiating a beam from the direction in which the cylinder portion 10 is located relative to the exterior body 20'' (see Figure 3). However, in the shock absorber 4, the bracket portion 203 is not provided at the time of welding, and the inserted portion 241 and the remaining portion 242 of the exterior body 20'' have a continuous tubular structure.

[0047] In the shock absorber 4, after welding the cylinder portion 10 and the exterior body 20″, a cut 211, for example, as shown by a dashed line in FIG. 9(a) is provided in the exterior body 20″. Then, the portion surrounded by the cut 211 is bent and developed radially outward at a bent portion 212 shown by a two-dot chain line, so that an expanded portion 211′ having a shape corresponding to the cut 211 is formed so as to protrude radially outward as shown in FIG. 9(b). Note that a through hole 213 corresponding to the shape of the cut 211 is formed in the exterior body 20″ after the expansion. For example, a cut 214 shown by a dashed line in FIG. 9(c) is provided, and the exterior body 20″ is bent and developed radially outward at a bent portion 215 shown by a two-dot chain line, so that an expanded portion 214′ protruding in a different direction can be formed as shown in FIG. 9(d). Note that a through hole 216 corresponding to the shape of the cut 214 is formed in the exterior body 20″ after the expansion.

[0048] In the shock absorber 4, by performing bending processing or processing to form holes or grooves on the unfolding portions 211' and 214', it is possible to form, for example, the bracket portion 203 similar to that of the shock absorber 1. Also, by processing the unfolding portions 211' and 214', it is possible to form the joint portion 209 and the rib portion 208 similar to those of the shock absorber 3. Note that the shape and position of unfolding, the direction of unfolding, and the number of points of unfolding are not limited, and may be determined according to the parts to be formed.

[0049] Here, the parts formed by unfolding are not limited to the bracket portion 203 and the joint portion 209 described above. For example, as shown in Fig. 10(a), a vehicle may be provided with a stabilizer 71 that suppresses vertical movement between two opposing wheels 101 (only one of them is shown). In this case, a stabilizer link 70 (an example of a stay) for attaching the stabilizer 71 may be formed by processing an unfolded portion 211' (see Fig. 9) or a unfolded portion 214' (see Fig. 9). In addition, a stay to which various accessories can be attached, such as a sensor that detects a state quantity related to the wheels 101 of the vehicle or a brake used for braking the vehicle, may be formed by processing the unfolded portion 211' or the unfolded portion 214'. Furthermore, for example, as shown in FIG. 10(b), when attaching bracket 109 independent of an exterior body or outer cylinder (exterior body 20″ in the figure) to shock absorber 4, a stopper is required to position bracket 109 with respect to the cylinder portion. In this case, bracket stopper 80 may be formed by processing expanded portion 211′ and expanded portion 214′.

[0050] It has been described herein that the shock absorber 4 has substantially the same configuration as the shock absorber 1 to which the first embodiment is applied, and that the bracket portion 203 and the like are formed by unfolding the remaining portion 242 of the exterior body 20″. However, for example, the shock absorber 4 may have substantially the same configuration as the shock absorber 2 to which the second embodiment is applied (see FIG. 6 ), and the bracket portion 203 and the like may be formed by unfolding the remaining portion of the outer cylinder.

[0051] <Fifth embodiment> Next, a fifth embodiment will be described with reference to Figures 11 and 12. In the fifth embodiment, parts similar to those in the first embodiment described above may be given the same names and symbols and descriptions thereof may be omitted. FIG. 11 is a diagram illustrating a schematic configuration of a shock absorber 5 to which the fifth embodiment is applied. FIG. 12 is a diagram illustrating the formation of the piston stopper 510 in the shock absorber 5, where (a) is a diagram showing the process of welding the tubular member 40 and the outer casing 50, and (b) to (d) are diagrams showing the process of forming the piston stopper 510 by processing the outer casing 50.

[0052] 11, the shock absorber 5 to which the fifth embodiment is applied includes a cylindrical member 40 extending in the center line direction, a free piston 16 movable in the center line direction within the cylindrical member 40, and a rod 11 and a piston 12 located on the other side of the free piston 16 within the cylindrical member 40. The shock absorber 5 also includes a cylindrical exterior body 50 into which a part of the cylindrical member 40 is inserted in the center line direction.

[0053] Oil (an example of a working fluid) is accommodated on the other side of the free piston 16, and gas (an example of a working fluid) is accommodated on one side inside the cylindrical member 40. In the shock absorber 5, the free piston 16 moves in conjunction with the movement of the rod 11 and the piston 12 in the center line direction, thereby adjusting the pressure of the accommodated oil and gas, and adjusting the shock absorber function.

[0054] The exterior body 50 has a cylindrical structure into which the cylindrical member 40 is inserted in the center line direction. More specifically, the exterior body 50 has an inserted portion 501 into which the cylindrical member 40 is inserted, and a remaining portion 502 that is the remainder of the entire length of the cylindrical member 40 in the center line direction excluding the inserted portion 501. The exterior body 50 also has an end face 507 at one end. The end face 507 has a piston stopper 510 that restricts the free piston 16 from moving more than a certain amount in one direction.

[0055] More specifically, the piston stopper 510 protrudes from the other side of the end face 507 toward the inside of the cylindrical structure of the exterior body 50, and restricts the movement of the free piston 16 to one side. Further, the piston stopper 510 divides the inside of the cylindrical member 40 into a storage section 511 that stores oil and gas, and a non-storage section 512 (outside air side) that does not store these. In other words, the piston stopper 510 is an example of a partition member.

[0056] Here, the cylindrical member 40 and the exterior body 50 in the shock absorber 5 are beam welded at a welded portion 500. More specifically, the welded portion 500 is formed by fusion welding one end surface 402 of the cylindrical member 40 and an inner circumferential surface 505 of the exterior body 50 together by irradiating a beam from a direction in which the cylindrical member 40 is located relative to the exterior body 50 (the radial center side in FIG. 11 ) at the boundary between the inserted portion 501 and the remaining portion 502. The piston stopper 510 is formed by processing the exterior body 50 after welding.

[0057] Here, an example of a manufacturing process for the shock absorber 5 to which the fifth embodiment is applied will be briefly described. 12(a), in manufacturing the shock absorber 5, first, the cylindrical member 40 and the exterior body 50 are welded together. As shown in the figure, at the time of welding, the exterior body 50 is in a tubular state with both ends open, and one end of the exterior body 50 does not have an end face 507, and an opening surrounded by an edge 508 exists. Then, the cylindrical member 40 and the exterior body 50 are welded together by irradiating a beam from the opening. Note that, at this stage, the remaining portion 504 has a length L4 in the center line direction.

[0058] After welding the cylindrical member 40 and the exterior body 50, as shown in FIG. 12(b), by using the concave type 61 and the convex type 62, the exterior body 50 is processed to be bent inside the cylindrical member 40. Then, as shown in FIG. 12(c), the edge 508 is gradually bent toward the other side. As the edge 508 is gradually bent toward the other side, the length of the remaining portion 504 in the center line direction becomes shorter, such as the remaining portion 504' shown in FIG. 12(b) and the remaining portion 504'' shown in FIG. 12(c). And finally, as shown in FIG. 12(d), the opening by the edge 508 is completely closed, and the piston stopper 510 is formed. Note that at this stage, the remaining portion 504 has a length L3 (<L4) in the center line direction. After that, the rod 11, the piston 12, and the free piston 16 are attached, and oil and gas are stored in the storage portion 511, and the shock absorber 5 is manufactured.

[0059] Also in the shock absorber 5 as described above, similar to the shock absorber 1 to which the first embodiment is applied, since the welded portion 500 is not exposed to the outside, it is suppressed that the appearance is damaged by welding. Further, by adjusting the length L3 in the center line direction of the remaining portion 503 after forming the piston stopper 510, the overall length required for the shock absorber 5 can be ensured.

Description of Reference Numerals

[0060] 1, 2, 3, 4, 5... shock absorber, 20, 20'... exterior body, 100, 100'... suspension device, 103... spring, 200, 300, 500... welded portion, 201... inserted portion, 202... remaining portion

Claims

1. A cylinder portion that contains a working fluid; an exterior body into which the cylinder portion is inserted in a center line direction of the cylinder portion, The exterior body is a cylindrical insertion portion into which the cylinder portion is inserted; a remaining portion that is a remainder excluding the inserted portion in the center line direction, The cylinder portion and the exterior body are welded at a boundary between the inserted portion and the remaining portion by irradiating a beam from a direction in which the cylinder portion is located relative to the exterior body. Buffer device.

2. The length L of the remaining portion in the center line direction is [0010] Fulfilling The shock absorber according to claim 1 .

3. A cylindrical member; a partition member that partitions the inside of the cylindrical member into a storage section that stores the working fluid and a non-storage section that does not store the working fluid; an exterior body into which the cylindrical member is inserted in a center line direction of the cylindrical member, The exterior body is an insertion portion into which the tubular member is inserted; a remaining portion that is a remainder excluding the inserted portion in the center line direction, the tubular member and the exterior body are welded at a boundary between the inserted portion and the remaining portion by irradiating a beam from a direction in which the tubular member is located relative to the exterior body on the remaining portion side, The partition member is formed by processing the exterior body after the welding. Buffer device.

4. A cylindrical member; a partition member that partitions the inside of the cylindrical member into a storage section that stores a working fluid and a remaining section that is a remainder excluding the storage section, The cylindrical member and the partition member are welded by irradiating a beam onto the cylindrical member on the remaining portion side from a direction in which the partition member is located. Buffer device.

5. The length L of the remaining portion in the center line direction of the cylindrical member is [0025] Fulfilling The shock absorber according to claim 4.

6. A shock absorber applied to a vehicle, a stay to which at least one of a sensor for detecting a state quantity related to the wheels of the vehicle, a brake for braking the vehicle, and a stabilizer for suppressing vertical movement between the two opposing wheels can be attached is formed on the remaining portion; A shock absorber according to any one of claims 1 to 5.

7. A suspension device applied to a vehicle, A shock absorber according to any one of claims 1 to 5; A spring disposed around the shock absorber; A suspension device comprising:

8. the remaining portion includes a connecting member for connecting the device to a connecting member that connects a body and a wheel of the vehicle, 8. The suspension system of claim 7.

9. the connecting member is a bracket for connecting the device to a hub unit to which a wheel of the vehicle is attached, The bracket is formed by cutting open a part of the cylindrical remaining portion.

9. The suspension system of claim 8.

10. the connecting member is a joint for connecting the device to a lower arm that supports an axle of the vehicle, The joint is formed by cutting open a part of the cylindrical remaining portion.

9. The suspension system of claim 8.

11. the remaining portion includes a rib that reduces the circumferential rigidity of a joint that connects the device to a connection member that connects a body and a wheel of the vehicle, The rib is formed by cutting open a part of the cylindrical remaining portion.

8. The suspension system of claim 7.

12. The shock absorber comprises: a bracket for fixing the device to a hub unit to which a wheel of the vehicle is attached; a stopper provided in the remaining portion for positioning the bracket relative to the cylinder portion or the accommodation portion, The stopper is formed by cutting open a part of the cylindrical remaining portion.

8. The suspension system of claim 7.

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