buffer

Abstract

To provide a damper of which the cost and the weight can be reduced.SOLUTION: A damper D comprises: a damper main body 1 including a cylindrical outer shell 2 and a rod 3 which is freely movably inserted into the outer shell 2; and a knuckle bracket 4 mounted in an outer periphery of a lower end of the outer shell 2. The knuckle bracket 4 is formed by bending one metal sheet as a base material and includes: a pair of crimping pieces 5 and 6 which are bent along an outer periphery of the outer shell 2 and crimp the outer shell 2; a pair of mounting pieces 7 and 8 which extend from circumferential ends of the crimping pieces 5 and 6 in a radial direction of the outer shell 2 and are opposed to each other; a connecting piece 9 connecting upper ends of the mounting pieces 7 and 8 with each other; and a pair of notches 10 and 11 cutting three-sided intersections where the crimping pieces 5 and 6 and the mounting pieces 7 and 8 cross the connecting pieces 9.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a shock absorber. [Background technology]

[0002] The shock absorber comprises an outer shell and a rod that is movably inserted into the outer shell, and is used, for example, by being incorporated into the suspension of a vehicle. When the piston rod moves axially relative to the outer shell, it exerts a damping force to suppress vibration of the vehicle body and wheels.

[0003] When a shock absorber incorporated into a suspension in this manner is used in a strut-type suspension, for example, a knuckle bracket for attaching a knuckle that holds a vehicle wheel is attached by welding to the lower end of the outer shell.

[0004] For example, a knuckle bracket includes a cylindrical holding portion with a C-shaped cross section that holds the outer periphery of the outer shell, a pair of mounting portions that extend parallel to each other radially outward from both circumferential ends of the holding portion and can be connected to the knuckle, and a reinforcing portion that is formed by bending the upper ends of each mounting portion in directions that bring them closer to each other (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-216129 Summary of the Invention [Problem to be solved by the invention]

[0006] In a shock absorber configured in this manner, the knuckle bracket has a holding portion that surrounds the outer periphery of the outer shell almost entirely, and a reinforcing portion that reinforces the mounting portion, so there are no problems with strength.However, since a large amount of material is used to form the knuckle bracket, material yield is poor, and the cost and weight of the shock absorber increase.

[0007] Therefore, an object of the present invention is to provide a shock absorber that can reduce costs and weight. [Means for solving the problem]

[0008] In order to solve the above problems, the shock absorber of the present invention comprises a shock absorber body having a cylindrical outer shell and a rod movably inserted into the outer shell, and a knuckle bracket attached to the outer periphery of the lower end of the outer shell, the knuckle bracket being formed by bending a single metal plate as a base material, and comprising a pair of clamping pieces that are curved along the outer periphery of the outer shell and clamp the outer shell, a pair of mounting pieces that extend from the circumferential ends of each clamping piece in the radial direction of the outer shell and face each other, and a pair of mounting pieces that are fixed to each other at the upper ends of the mounting pieces. Or bottom ends together and a pair of notches that cut out the three-plane intersection where the clamping piece, the attachment piece, and the connecting piece intersect.

[0009] In a shock absorber configured in this manner, the knuckle bracket can be firmly fixed to the outer shell even though the clamping pieces of the knuckle bracket do not surround the outer periphery of the outer shell, and the box-shaped configuration of the mounting pieces and connecting pieces increases the strength of the knuckle bracket so that it can withstand the load input from the knuckle. Furthermore, because the knuckle bracket has notches that remove the three-sided intersections where the clamping pieces, mounting pieces, and connecting pieces intersect, it can be firmly fixed to the outer shell and a high-strength knuckle bracket can be easily molded. Furthermore, because the knuckle bracket does not have a holding portion that surrounds the outer shell like conventional knuckle brackets, it is smaller than conventional knuckle brackets, requiring less material for manufacturing and resulting in a lighter weight.

[0010] Alternatively, the notch in the knuckle bracket may be rectangular with the corners chamfered to form a rounded surface. In a shock absorber configured in this manner, the provision of the notch can alleviate stress concentration when a load is input from the knuckle to the knuckle bracket.

[0011] Furthermore, the notch in the knuckle bracket may be provided so as to cut out across three surfaces of the clamping piece, the mounting piece, and the connecting piece. With a shock absorber configured in this manner, the clamping piece, the mounting piece, and the connecting piece can be prevented from interfering with each other's deformation, thereby effectively preventing springback after molding of the knuckle bracket. [Effects of the Invention]

[0012] The shock absorber of the present invention reduces costs and weight. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is a side view of the shock absorber according to the embodiment. [Figure 2] FIG. 2 is a front view of a knuckle bracket of the shock absorber according to the embodiment. [Figure 3] FIG. 2 is a side view of a knuckle bracket of the shock absorber according to the embodiment. [Figure 4] FIG. 1 is a plan view of a knuckle bracket attached to a shock absorber according to an embodiment. [Figure 5] (a) is a flat plate punched into the unfolded shape of the knuckle bracket. (b) is a semi-finished knuckle bracket with the clamping piece and mounting piece molded. (c) is a semi-finished knuckle bracket after the bolt insertion holes have been drilled in the mounting piece. [Figure 6] FIG. 10 is a perspective view of a knuckle bracket according to a modified example of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described below based on the embodiments shown in the drawings. As shown in Figures 1 and 2, shock absorber D includes a shock absorber body 1 having an outer shell 2 and a rod 3 movably inserted into the outer shell 2, and a knuckle bracket 4 attached by welding to the outer periphery of the lower end side of the outer shell 2. The shock absorber is connected to a knuckle that supports a wheel of a vehicle (not shown) using the knuckle bracket 4, and is interposed between the body and wheel of the vehicle.

[0015] Below, we will explain in detail each part of the shock absorber D. The shock absorber main body 1 has a cylindrical outer shell 2 and a rod 3 that is movably inserted into the outer shell 2, and when the rod 3 moves axially relative to the outer shell 2 in an expansion / contraction operation, a damping force is generated that prevents the rod 3 from moving relative to the outer shell 2, thereby damping vibrations of the vehicle body and wheels.

[0016] The shock absorber body 1 includes, for example, a cylindrical outer shell 2 with a closed lower end, a cylinder (not shown) housed in the outer shell 2, a rod 3 movably inserted into the cylinder, a piston connected to the rod 3 and inserted into the cylinder to divide the interior of the cylinder into an extension-side chamber and a compression-side chamber, a reservoir formed between the cylinder and the outer shell 2, and a valve case provided at the lower end of the cylinder to separate the compression-side chamber from the reservoir. The extension-side chamber and the compression-side chamber are filled with a liquid such as hydraulic oil, and the reservoir is filled with a liquid and a gas. The liquid used in the shock absorber D may be a liquid other than hydraulic oil, such as water or an aqueous solution. The outer shell 2 is a member forming the outermost shell of the shock absorber body 1 to which the knuckle bracket 4 is attached. If the shock absorber body 1 is configured as an inverted type, the outer shell 2 may be a member that covers the rod instead of housing a cylinder or the like.

[0017] Also, Buffer body 1 a passage communicating between the expansion-side chamber and the compression-side chamber, and a passage communicating between the compression-side chamber and the reservoir. Each aisle is equipped withIn the shock absorber body 1 configured in this manner, the expansion-side chamber and the compression-side chamber are expanded and contracted by the piston during expansion and contraction, causing the liquid to move through the passages, and the damping valves provide resistance to the flow of this liquid, generating a damping force.

[0018] A lower suspension spring bearing 16 that supports the lower end of a suspension spring (not shown) is attached to the outer periphery of the middle part of the outer shell 2. The suspension spring (not shown) is interposed between an upper suspension spring bearing attached to the tip of the rod 3 and the lower suspension spring bearing 16, and when the shock absorber D is interposed between the vehicle body and the wheel, it elastically supports the vehicle body.

[0019] As shown in FIGS. 1 to 4, the knuckle bracket 4 is formed by punching a single metal plate into the developed shape of the knuckle bracket 4 and then bending the plate. 。 The knuckle bracket 4 includes a pair of clamping pieces 5, 6 that curve along the outer periphery of the outer shell 2 and clamp the outer shell 2, a pair of mounting pieces 7, 8 that extend radially from the circumferential ends of each of the clamping pieces 5, 6 and face each other, a connecting piece 9 that connects the ends of the mounting pieces 7, 8, and a pair of notches 10, 11 that cut out the three-plane intersection where the clamping pieces 5, 6, the mounting pieces 7, 8, and the connecting piece 9 intersect.

[0020] The clamping pieces 5, 6 are each a plate curved to follow the outer peripheral shape of the lower end of the outer shell 2 when viewed from the axial direction of the outer shell 2, and abut their inner peripheral side surfaces along the axial direction of the outer shell 2 when viewed from the side of the outer shell 2.

[0021] The tips of the clamping pieces 5, 6, which are the circumferential ends opposite the mounting piece, do not extend beyond half of the outer shell 2 when viewed from the axial direction of the outer shell 2. In this way, because the tips of the clamping pieces 5, 6, which are the circumferential ends opposite the mounting piece, do not extend beyond half of the outer shell 2 when viewed from the axial direction of the outer shell 2, when the knuckle bracket 4 is brought into contact with the outer periphery of the lower end of the outer shell 2 in order to weld it to the outer periphery of the outer shell 2, it is sufficient to approach the knuckle bracket 4 from the side of the outer shell 2, making assembly work easier.

[0022] The mounting pieces 7, 8 extend parallel to each other in the radial direction of the outer shell 2 from the circumferential base ends of the clamping pieces 5, 6, respectively, and are opposed to each other, and are provided with two bolt insertion holes 7a, 8a each at positions that can face two holes provided in the mounting portion of the knuckle (not shown).The mounting portion of the knuckle (not shown) is inserted between the mounting pieces 7, 8, and the mounting pieces 7, 8 are fastened to the mounting portion by bolts and nuts (not shown) that pass through the mounting portion of the knuckle inserted into the bolt insertion holes 7a, 8a, thereby attaching the knuckle bracket 4 to the knuckle.

[0023] Furthermore, the lower ends of mounting piece 7 and clamping piece 5 and the lower ends of mounting piece 8 and clamping piece 6 are bent outward away from the outer shell 2 to provide flange-shaped reinforcing ribs 12, 13. Furthermore, a bulge 14 is provided that extends from the vertical center of mounting piece 7 to the vertical center of clamping piece 5 and bulges out away from the outer shell 2, and a bulge 15 is provided that extends from the vertical center of mounting piece 8 to the vertical center of clamping piece 6 and bulges out away from the outer shell 2. Reinforcing ribs 12, 13 and bulge portions 14, 15 are provided to improve the strength of the knuckle bracket 4 against loads that deform it.

[0024] Furthermore, the upper ends of the mounting pieces 7, 8 are connected by a connecting piece 9 that is perpendicular to the mounting pieces 7, 8. The side of the connecting piece 9 that faces the clamping pieces 5, 6 and faces the outer peripheral surface of the outer shell 2 is curved to fit along the outer periphery of the outer shell 2, and when the clamping pieces 5, 6 are brought into contact with the outer periphery of the outer shell 2, the side of the connecting piece 9 also abuts against the outer periphery of the outer shell 2. In this way, the knuckle bracket 4 has a structure in which the mounting pieces 7, 8 and the connecting piece 9 are box-shaped, and the base ends of the mounting pieces 7, 8 are connected to the clamping pieces 5, 6, respectively.

[0025] The knuckle bracket 4 also has notches 10 and 11 at the upper end of the boundary between the clamping piece 5 and the mounting piece 7, and at the upper end of the boundary between the clamping piece 6 and the mounting piece 8. Notch 10 is provided so as to cut out a three-plane intersection, which is the intersection of three faces of the clamping piece 5, the mounting piece 7, and the connecting piece 9, and notch 11 is provided so as to cut out a three-plane intersection, which is the intersection of three faces of the clamping piece 6, the mounting piece 8, and the connecting piece 9. Notches 10 and 11 are provided so as to cut out across three faces of the clamping piece 5, the mounting piece 7, and the connecting piece 9, including the three-plane intersection.

[0026] Each notch 10, 11 is formed by cutting a rectangular portion of the base material downward, opening from the upper end of the boundary between the clamping pieces 5, 6, the mounting pieces 7, 8 and the connecting piece 9, and has chamfered portions 10a, 11a formed by chamfering the four corners in an R-shape.

[0027] The knuckle bracket 4 configured as above is manufactured by the following procedure. difference First, a rectangular metal flat blank (not shown) is punched out to obtain a flat plate having the shape of the unfolded knuckle bracket 4 shown in FIG. 5(a). Next, the flat plate is bent and shaped by pressing to form the clamping pieces 5, 6, mounting pieces 7, 8, reinforcing ribs 12, 13, and bulge portions 14, 15 as shown in FIG. 5(b), and then bolt insertion holes 7a, 8a are punched in the mounting pieces 7, 8 as shown in FIG. 5(c). OpenBy bending the cut semi-finished product of the knuckle bracket 4 along the dashed lines in Figure 5(c), the connecting piece 9 and the mounting pieces 7, 8 are bent at right angles, and the knuckle bracket 4 can be manufactured.

[0028] The knuckle bracket 4 is manufactured in this manner, but the two three-plane intersections of the clamping pieces 5, 6, the mounting pieces 7, 8, and the connecting piece 9 are removed by the notches 10, 11, respectively, and the boundaries between the clamping pieces 5, 6, the connecting piece 9, and each of the mounting pieces 7, 8 are not continuous. Therefore, the clamping pieces 5, 6 do not interfere with the bending process when bending the boundaries between the connecting piece 9 and each of the mounting pieces 7, 8. Therefore, even a knuckle bracket 4 having a shape in which three-plane intersections are formed among the clamping pieces 5, 6, the mounting pieces 7, 8, and the connecting piece 9 can be easily formed. Note that it is possible to tilt the upper surfaces of the clamping pieces 5, 6 so that the axial length becomes shorter toward the circumferential tip of the clamping pieces 5, 6 so that the clamping pieces 5, 6 do not interfere with the bending process. However, such tilting may make the forming more difficult and may result in a shorter weld length than if the clamping pieces 5, 6 were not tilted.

[0029] When the curved inner surfaces of the clamping pieces 5, 6 of the knuckle bracket 4 obtained in this manner are abutted against the outer surface of the outer shell 2, the horizontal side of the connecting piece 9, which is perpendicular to the axial direction of the outer shell 2, abuts against the outer surface of the outer shell 2.

[0030] Then, the knuckle bracket 4 is fixed to the outer shell 2 by arc welding from the tip side of the upper end of the clamping piece 5, passing above the side of the connecting piece 9, to the tip side of the upper end of the opposite clamping piece 6, and by arc welding the tips of each clamping piece 5, 6 to the outer periphery of the outer shell 2 along the axial direction.

[0031] Thus, in shock absorber D of this embodiment, a C-shaped weld B1 is formed from near the anti-mounting end of the upper end of clamping piece 5, passing above the side surface of connecting piece 9, to near the anti-mounting end of the upper end of opposite clamping piece 6, and a linear weld B2 is formed along the axial direction of outer shell 2, from near the upper end to near the lower end of each of clamping pieces 5, 6. Note that welds B1, B2 are formed by melting the weld material and the weld material of knuckle bracket 4 and outer shell 2.

[0032] The knuckle bracket 4 is attached to the outer shell 2 by welding the upper ends and opposite mounting piece side ends of the clamping pieces 5, 6 and the connecting piece 9 to the outer periphery of the outer shell 2, so that the clamping pieces 5, 6 are firmly fixed to the outer shell 2 even though they do not surround the periphery of the outer shell 2 like the holding parts of conventional knuckle brackets.

[0033] In addition, the knuckle bracket 4 is equipped with a connecting piece 9 that connects the upper ends of the mounting pieces 7, 8, and the mounting pieces 7, 8 and the connecting piece 9 form a box shape, which provides high strength and is able to fully withstand various loads such as bending, shearing, and tension input from the knuckle that supports the vehicle wheel.

[0034] Thus, to obtain a knuckle bracket 4 with high strength, it is essential to have connecting pieces 9 that connect the upper ends of the clamping pieces 5, 6 at the upper ends of the mounting pieces 7, 8 from their bases; however, if notches 10, 11 are not provided, the three-plane intersections, which are the intersections of the three faces of the clamping pieces 5, 6, mounting pieces 7, 8, and connecting piece 9, will remain in the base material, making it difficult to bend the mounting pieces 7, 8 at right angles to the connecting piece 9 and making it extremely difficult to mold the knuckle bracket 4. However, in shock absorber D of this embodiment, knuckle bracket 4 is provided with notches 10, 11 that remove the three-plane intersections where the clamping pieces 5, 6, mounting pieces 7, 8, and connecting piece 9 intersect, so that when bending the connecting piece 9 at the boundaries between the connecting piece 9 and each mounting piece 7, 8, the knuckle bracket 4 can be molded smoothly without the clamping pieces 5, 6 getting in the way of the bending molding.

[0035] As described above, the shock absorber D of this embodiment comprises a shock absorber body 1 having a cylindrical outer shell 2 and a rod 3 that is movably inserted into the outer shell 2, and a knuckle bracket 4 that is attached to the outer periphery of the lower end of the outer shell 2. The knuckle bracket 4 is formed by bending a single metal plate as the base material, and comprises a pair of clamping pieces 5, 6 that curve along the outer periphery of the outer shell 2 and clamp the outer shell 2, a pair of mounting pieces 7, 8 that extend radially from the circumferential ends of each clamping piece 5, 6 and face each other, a connecting piece 9 that connects the ends of the mounting pieces 7, 8, and a pair of notches 10, 11 that cut out the three-sided intersection where the clamping pieces 5, 6, the mounting pieces 7, 8 and the connecting piece 9 intersect.

[0036] In shock absorber D configured in this manner, even though the clamping pieces 5, 6 of knuckle bracket 4 do not surround the outer periphery of outer shell 2, knuckle bracket 4 can be firmly fixed to outer shell 2, and because the mounting pieces 7, 8 and connecting piece 9 form a box shape, the strength of knuckle bracket 4 is increased so that it can withstand the load input from the knuckle. Furthermore, knuckle bracket 4 is provided with a pair of notches 10, 11 that remove the three-plane intersection where clamping pieces 5, 6, mounting pieces 7, 8, and connecting piece 9 intersect, so that it can be firmly fixed to outer shell 2 and a high-strength knuckle bracket 4 can be molded without difficulty.

[0037] Furthermore, the knuckle bracket 4 does not have a holding portion that surrounds the outer shell 2 like conventional knuckle brackets, so it is smaller than conventional knuckle brackets, requiring less material for manufacturing and is lighter in weight.

[0038] As described above, according to the shock absorber D of this embodiment, it is possible to use a small and lightweight knuckle bracket 4, which improves the material yield in manufacturing the knuckle bracket 4, thereby reducing the cost of manufacturing the shock absorber D and the overall weight of the shock absorber D.

[0039] As described above, the knuckle bracket 4 is configured so that the upper ends of the mounting pieces 7, 8 are connected by the connecting piece 9, but if the lower ends of the mounting pieces 7, 8 are configured so that they are connected by the connecting piece, the notches 10, 11 can be provided so as to cut out the three-plane intersection where the clamping pieces 5, 6 and the connecting piece intersect at the lower ends of the mounting pieces 7, 8.

[0040] Furthermore, in the shock absorber D of this embodiment, the notches 10 and 11 are rectangular and have rounded corners, so that the provision of the notches 10 and 11 can reduce stress concentration when a load is input from the knuckle to the knuckle bracket 4.

[0041] The width and length of notches 10 and 11 can be designed arbitrarily as long as the intersection of the three surfaces can be removed, but they should be designed in a way that does not significantly reduce the strength of knuckle bracket 4 and takes into consideration the life and maintainability of the mold used to punch out the flat plate in the unfolded shape of knuckle bracket 4 shown in Figure 5(a).

[0042] Furthermore, in shock absorber D of this embodiment, notches 10, 11 in knuckle bracket 4 are provided so as to cut out across three surfaces of clamping pieces 5, 6, mounting pieces 7, 8, and connecting piece 9. With shock absorber D configured in this manner, it is possible to prevent the clamping pieces 5, 6, mounting pieces 7, 8, and connecting piece 9 from interfering with each other's deformation, thereby effectively preventing springback of knuckle bracket 4 after molding.

[0043] The shapes and dimensions of the mounting pieces 7, 8 and connecting pieces 9 of the knuckle bracket 4 can be modified as needed depending on the outer diameter of the outer shell 2, the shape of the vehicle knuckle, and the like, as long as the aforementioned effects are not lost. The circumferential tips of the clamping pieces 5, 6 can extend or protrude beyond half of the outer shell 2 toward the non-mounting side as long as this does not interfere with welding to the outer shell 2. However, this increases the weight of the clamping pieces 5, 6 and makes it impossible to insert the outer shell 2 between the clamping pieces 5, 6 from the side. Therefore, it is preferable that the circumferential tips of the clamping pieces 5, 6, which are the non-mounting side ends, do not extend beyond half of the outer shell 2 as viewed in the axial direction of the outer shell 2. The length of the circumferential tips of the clamping pieces 5, 6 in the axial direction of the outer shell 2 can be modified as needed depending on the joint strength required by the specifications.

[0044] 6, the knuckle bracket 4A may have a structure in which the clamping pieces 5a, 6a and the mounting pieces 7a, 8a extend upward relative to the knuckle bracket 4, and the connecting piece 9a is inclined relative to the outer shell 2. Even in the knuckle bracket 4A configured in this manner, by providing notches 10a, 11a that remove the three-sided intersection of the clamping pieces 5a, 6a, the mounting pieces 7a, 8a, and the connecting piece 9a, the knuckle bracket 4A can be firmly fixed to the outer shell 2, can be molded easily, and achieves high strength. Therefore, a shock absorber using the knuckle bracket 4A configured in this manner improves material yield in the manufacture of the knuckle bracket 4A, thereby reducing the cost of manufacturing the shock absorber and the overall weight of the shock absorber.

[0045] Although the preferred embodiment of the present invention has been described in detail, modifications, variations and changes can be made thereto without departing from the scope of the appended claims. [Explanation of symbols]

[0046] 1···Shock absorber body, 2···Outer shell, 3···Rod, 4, 4A···Knuckle bracket, 5, 5a, 6, 6a···Clamping piece, 7, 7a, 8, 8a···Mounting piece, 9, 9a···Connecting piece, 10, 10a, 11, 11a···Notch, D···Shock absorber

Claims

1. a shock absorber body having a cylindrical outer shell and a rod movably inserted into the outer shell; a knuckle bracket attached to an outer periphery of a lower end of the outer shell, The knuckle bracket is The base material is a single metal plate. a pair of clamping pieces that are curved along the outer periphery of the outer shell and clamp the outer shell; a pair of attachment pieces extending from circumferential ends of each of the clamping pieces in a radial direction of the outer shell and facing each other; a connecting piece that connects the upper ends or lower ends of the mounting pieces; a pair of notches that cut out the three-plane intersection where the clamping piece, the attachment piece, and the connecting piece intersect; A shock absorber characterized by:

2. The notch is rectangular, and the corners are chamfered to have a rounded surface.

2. The shock absorber according to claim 1.

3. The notch is provided so as to cut across three surfaces of the clamping piece, the attachment piece, and the connecting piece.

3. The shock absorber according to claim 1 or 2.

Images