JP2011220435A - Method of manufacturing vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a vibration control device, capable of forming a stopper member while suppressing the manufacturing cost.SOLUTION: If an outer tube member 20 is pressed toward radially inward by respective dice pieces M1a, M1b, in a vulcanization process, a straight line wall is compressed by an arc wall from both end sides, and as the dice piece M1b is abutted to an outer circumferential surface side, a relief space for plastic deformation is lost, and part thereof is bulged toward radially inward thereof, forming a stopper part 21. Thus, by applying a drawing process to the outer tube member 20, the stopper part 21 can be formed, eliminating the need for formation of a bulge and arrangement of a spacer fitting, so that the production cost can be suppressed.

Description

  The present invention relates to a method for manufacturing a vibration isolator, and more particularly to a method for manufacturing a vibration isolator capable of forming a stopper member while suppressing manufacturing costs.

  As an anti-vibration device for supporting a vibration generating body such as an engine on a vehicle body, a cylindrical inner cylinder member, a cylindrical outer cylinder member arranged at an interval on the outer peripheral side of the inner cylinder member, and an inner cylinder member An anti-vibration device comprising a pair of anti-vibration legs that are positioned between the inner cylinder member and the outer cylinder member and that are arranged in a V shape and are made of a rubber-like elastic body is known. (Patent Document 1).

  In such an anti-vibration device, when the pair of anti-vibration legs are thermally contracted after vulcanization molding, the inner cylindrical member is pulled and moved to one side due to the influence of the thermal contraction, and accordingly, the other of the inner cylindrical members is The clearance on the side increases (the straight part becomes wider). In this case, in anticipation of the movement of heat shrinkage, vulcanization molding may be considered in a state in which the inner cylinder member is preliminarily shifted in the direction in which the clearance is reduced (i.e., the direction in which the straight portion is narrowed), Since the thickness of the vulcanization mold that forms the sharpened portion is reduced and there is a limit in terms of strength, it is difficult to ensure an appropriate clearance only by shifting the position of the inner cylinder member.

  Therefore, in the conventional vibration isolator, a bulge (protrusion) is formed on the outer peripheral surface of the inner cylinder member, or a spacer metal fitting is disposed on the inner peripheral side of the outer cylinder member, and these bulge and spacer metal fitting are used as a stopper member. By using it, even if the inner cylinder member moves due to thermal contraction, an appropriate clearance is secured and the relative displacement between the inner cylinder member and the outer cylinder member can be regulated within a predetermined range.

JP 2001-173710 A (FIG. 1 and the like)

  However, in the conventional vibration isolator described above, it is necessary to form a bulge on the inner cylinder member and to separately arrange a spacer metal fitting, and accordingly, man-hours associated with the formation of the bulge and the arrangement of the spacer metal fitting are reduced. Since it increases, there is a problem that the manufacturing cost increases in forming the stopper member.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a method for manufacturing a vibration isolator capable of forming a stopper member while suppressing manufacturing costs.

Means for Solving the Problems and Effects of the Invention

  According to the method for manufacturing a vibration isolator according to claim 1, in the vulcanization step, after the inner cylinder member and the outer cylinder member are installed in the cavity of the vulcanization mold, into the cavity of the vulcanization mold. A rubber-like elastic body is injected and vulcanized to form a vulcanized molded body in which the outer peripheral surface of the inner cylindrical member and the inner peripheral surface of the outer cylindrical member are connected by a pair of vibration isolation legs. The Next, the vulcanized molded body is transferred to a drawing process, and installed in a drawing die having a plurality of die pieces arranged in parallel in the circumferential direction so as to form a radial shape. Thereafter, a plurality of die pieces are displaced toward the inside in the radial direction of the vulcanized molded body, and the outer cylinder member of the vulcanized molded body is subjected to a drawing process so that the outer periphery of the outer cylinder member of the vulcanized molded body The surface is pressed radially inward by the inner peripheral surfaces of the plurality of die pieces.

  In this case, the outer cylinder member has one or a plurality of arc wall portions in which a cross-sectional shape perpendicular to the axis before the drawing process is formed in an arc shape, and a cross-sectional shape perpendicular to the axis before the drawing process One or a plurality of straight wall portions formed in a straight line, and the vulcanization step is connected to the arc wall portions with the pair of vibration-proof leg portions sandwiching the straight wall portions of the outer cylinder member, respectively. Since the vulcanized molded body is formed, when the arc wall portion and the straight wall portion of the outer cylinder member are pressed by the inner peripheral surface of the die piece and displaced radially inward in the drawing step, the arc wall portion is The straight wall portion having both ends connected to the circular arc wall portion is compressed from the both end sides by the circular arc wall portion. Since the outer peripheral surface of the straight wall portion is in contact with the inner peripheral surface of the die piece and the displacement is restricted, the plurality of die pieces are further displaced toward the radially inner side of the vulcanized molded body, A part of the straight wall portion compressed from both ends by the arc wall portion and restricted to the outer peripheral surface side by the die piece can be bulged inward in the radial direction. As a result, the stopper member can be formed by the portion that bulges to the inner peripheral surface side of the straight wall portion.

  As a result, even when the position of the inner cylinder member is moved due to the thermal contraction of the pair of vibration isolation legs and the clearance is enlarged (the straight portion is widened), the stopper member is Since it can form, an appropriate clearance can be ensured and the relative displacement of an inner cylinder member and an outer cylinder member can be controlled within a predetermined range. In addition, the stopper member can be formed by drawing the outer cylinder member, and unlike the conventional product, it is not necessary to form a bulge or dispose a spacer metal fitting. There is an effect that it can be formed.

  In the vibration isolator that connects the inner cylinder member and the outer cylinder member with the vibration isolation leg portion, the outer cylinder is used to relieve the tensile stress generated in the vibration isolation leg portion due to the heat shrinkage after vulcanization molding. The member is drawn. Therefore, in claim 1, the drawing for relieving the tensile stress can be combined with the drawing for forming the stopper member described above. That is, an additional process for forming the stopper member is not necessary, and an increase in the number of man-hours can be suppressed, so that also in this respect, the manufacturing cost can be reduced.

  According to the first aspect of the present invention, the reduced diameter of the arc wall portion and the straight wall portion are maintained while maintaining the outer peripheral surface of the arc wall portion and the straight wall portion of the outer cylinder member in close contact with the inner peripheral surface of the die piece. Since the stopper member can be formed, the shape of the arc wall portion is made to be the shape along the inner peripheral shape of the die piece, and the vibration isolator capable of securing the press-fitting load to the mating member is manufactured. There is an effect that can be. That is, the stopper member can be formed by pressing a convex die piece corresponding to the shape of the stopper member from the outer peripheral surface thereof against the straight wall portion of the outer cylinder member. Since the arc wall portion is pulled by the deformation of the wall portion and the sagging occurs in the arc shape (R shape) of the arc wall portion, the manufactured vibration isolator has a small press-fitting load. On the other hand, according to the first aspect, as described above, since the arc shape of the arc wall portion can be made to conform to the shape of the inner peripheral surface of the die piece, a vibration isolator capable of securing a press-fit load is manufactured. be able to.

  According to the method for manufacturing a vibration isolator according to claim 2, in addition to the effect produced by the method for manufacturing a vibration isolator according to claim 1, the outer cylindrical member has a cross-sectional shape perpendicular to the axis before the drawing step. In the drawing process, the length of the straight wall portion is shorter than half the circumference of the circular arc wall portion. Therefore, it is possible to reliably form a bulging portion as a stopper member, and to prevent the straight wall portion from being excessively long and deforming irregularly. effective.

  According to the manufacturing method of the vibration isolator according to claim 3, in addition to the effect exerted by the method of manufacturing the vibration isolator according to claim 1 or 2, the outer cylindrical member is the circumferential end of one arcuate wall portion. Since both ends of one straight wall portion are connected to each other and the cross-sectional shape perpendicular to the axis before the drawing process is formed into a shape in which a part of a circle is divided by a string, an arc wall is used in the drawing process. By securing the length of the part, the straight wall part can be sufficiently compressed from both end sides, the stopper member can be reliably formed, and the entire arc wall part is circular, so that the arc wall part It is easy to make the shape of the shape along the inner peripheral shape of the die piece, and there is an effect that it is possible to manufacture a vibration isolator that can ensure a press-fit load.

  According to the method for manufacturing a vibration isolator according to claim 4, in addition to the effect produced by the method for manufacturing a vibration isolator according to any one of claims 1 to 3, the drawing step includes at least one of the plurality of die pieces. Using a drawing die formed so that the inner peripheral surface of one die piece is in contact with both the outer peripheral surface of the straight wall portion and the outer peripheral surface of the arc wall portion, Since the cylindrical member is drawn, the outer peripheral surface of the portion (boundary) where the linear wall portion and the arc wall portion are connected can also be supported (pressed radially inward) by the inner peripheral surface of the die piece. . Therefore, since the displacement of the arc wall part and the load from the arc wall part can be stably transmitted to the straight wall part while suppressing the inhibition by the gap between the die pieces, the deformation of the straight wall part Has the effect of suppressing the occurrence of irregularities. As a result, the stopper member can be reliably formed.

(A) is a top view of the vibration isolator in 1st Embodiment of this invention, (b) is sectional drawing of the vibration isolator in the Ib-Ib line | wire of Fig.1 (a). (A) is a top view of an outer cylinder member, (b) is sectional drawing of the outer cylinder member in the IIb-IIb line | wire of Fig.2 (a). (A) is a top view of a vulcanization molded object, (b) is sectional drawing of the vulcanization molded object in the IIIb-IIIb line | wire of Fig.3 (a). It is a top view of the drawing die in a state before performing drawing. It is a top view of the drawing die in the state after performing drawing. (A) is a top view of the vibration isolator in 2nd Embodiment of this invention, (b) is sectional drawing of the vibration isolator in the VIb-VIb line | wire of Fig.6 (a). (A) is a top view of an outer cylinder member, (b) is sectional drawing of the outer cylinder member in the VIIb-VIIb line | wire of Fig.7 (a). It is a top view of the drawing die in a state before performing drawing. It is a top view of the drawing die in the state after performing drawing.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. First, the overall configuration of the vibration isolator 100 will be described with reference to FIG. FIG. 1A is a top view of the vibration isolator 100 according to the first embodiment of the present invention, and FIG. 1B is a cross-sectional view of the vibration isolator 100 taken along the line Ib-Ib in FIG. FIG. In FIG. 1, the shape of each component is schematically illustrated for easy understanding.

  The vibration isolator 100 is for supporting a vibration generating body such as an engine on a vehicle body, and is disposed on the outer peripheral side of the inner cylinder member 10 and the cylinder. The outer cylinder member 20 is formed in a shape, and the vibration isolating member 30 is connected to the outer peripheral surface of the inner cylinder member 10 and the inner peripheral surface of the outer cylinder member 20 and is made of a rubber-like elastic body.

  The inner cylinder member 10 is formed in a cylindrical shape having an axis O from a steel material, and is disposed at a position offset upward (upper side in FIG. 1A) from the center of the outer cylinder member 20. The inner cylinder member 10 is fastened and fixed to a member on the vibration generator side by a bolt (not shown) inserted through the inner periphery thereof.

  The outer cylinder member 20 is formed of a steel material into a cylindrical shape having an oval cross section, and the stopper portion 21 is provided so as to project toward the inner cylinder member 10 from two opposing positions on the inner peripheral surface thereof. The stopper portion 21 is a part for adjusting the clearance between the inner cylinder member 10 and the outer cylinder member 20 to restrict the relative displacement of both the members 10 and 20 within a predetermined range. The outer cylinder member 20 is press-fitted and fixed in a press-fitting hole of a bracket member (not shown) that is a member on the vehicle body side.

  The vibration isolation member 30 has a pair of vibration isolation legs 31 whose one end is connected to the outer peripheral surface of the inner cylinder member 10 and whose other end is connected to the inner peripheral surface of the outer cylinder member, and the inner periphery of the outer cylinder member 20. A lower protrusion 32 protruding from the surface toward the inner cylinder member 10 and a film part 33 covering the inner peripheral surface of the outer cylinder member 20 are provided.

  The pair of anti-vibration legs 31 are connected to each other at one end connected to the inner cylinder member 10, whereby the inner cylinder member 10 is covered by the one end side of the anti-vibration legs 31 over the entire circumference. It has been broken. The pair of anti-vibration legs 31 are extended from the connecting portion (one end side) to the inner cylinder member 10 toward the inner peripheral surface of the outer cylinder member 20 so as to expand toward the end in the axial direction. A certain other end side is connected to the inner peripheral surface of the outer cylinder member 20 at a position shifted slightly downward (lower side in FIG. 1A) from the long axis of the outer cylinder member 20.

  The lower protrusion 32 is formed in a trapezoidal shape having an upper base on the inner cylinder member 10 side when viewed in the axial direction. The film part 33 is an inner peripheral surface of the outer cylinder member 20 and is disposed in a region excluding a part to which the pair of vibration-proof leg parts 31 and the lower protrusions 32 are connected. The film part 33 is formed in a film shape having a thickness equal to or less than the plate thickness of the outer cylinder member 20 (see FIG. 2) before the drawing process. Thereby, it can suppress that formation of the stopper part 21 is prevented in the narrowing process mentioned later. Note that the vibration isolating base 30 is formed with a pair of straight portions 34 and 35 penetrating in the axial direction.

  Next, the detailed configuration of the outer cylinder member 20 will be described with reference to FIG. 2A is a top view of the outer cylinder member 20, and FIG. 2B is a cross-sectional view of the outer cylinder member 20 taken along line IIb-IIb in FIG. 2A. Note that the outer cylinder member 20 shown in FIG. 2 is shown in a state before being drawn by the drawing process.

  As shown in FIG. 2, the outer cylindrical member 20 is a member formed in a cylindrical shape from a steel material, and the cross-sectional shape perpendicular to the axial center before performing the drawing step is the axial direction (FIG. ) Formed in the same shape along the vertical direction). Specifically, the cross-sectional shape perpendicular to the axis of the outer cylinder member 20 is formed in an oval shape in which two semicircles are connected by two opposing straight lines.

  That is, the outer cylinder member 20 includes two arcuate wall portions 20a formed in a semicircular shape having a central angle of 90 degrees in the cross-sectional shape perpendicular to the axis before the drawing process, and the axis before the drawing process. The cross-sectional shape perpendicular | vertical to is formed in linear form, and is provided with the two linear wall parts 20b which are opposingly arranged in parallel.

  Thus, in the present embodiment, since the outer cylinder member 20 is formed in an oval shape, an arc shape having a radius different from that of the arc wall portion 20a is provided between the arc wall portion 20a and the straight wall portion 20b. Both wall portions 20a and 20b can be smoothly connected without interposing a portion. As a result, the dimensional accuracy required for the vulcanization mold in the vulcanization step can be relaxed, and the manufacturing cost can be reduced. Further, since the outer cylinder member 20 has a simple shape, the drawing process in the drawing process can be stably performed.

  Here, the outer cylinder member 20 has a cross-sectional shape perpendicular to the axial center before the drawing step, and the length of the straight wall portion 20b is set to be half (1/2) of the circumferential length of the circular arc wall portion 20a. It is preferable that the length is shorter than the length of 1/8 of the circumference of the arcuate wall portion 20a. By making the length shorter than half of the circumferential length, the length (circumferential length) of the arc wall portion 20a can be secured in the drawing step described later, and the straight wall portion 20b can be sufficiently compressed from both ends, and the stopper This is because the bulging portion as the portion 21 (see FIG. 1) can be reliably formed and the length of the straight wall portion 20b is excessively large, and the deformation thereof can be suppressed. . On the other hand, by making it longer than 1/8 of the circumferential length, when the straight wall portion 20b is compressed from both ends by the circular arc wall portion 20a in the drawing step to form the bulging portion as the stopper portion 21, When the length of the straight wall portion 20b is insufficient and the arc wall portion 20a is pulled by the deformation (bulge) of the straight wall portion 20b, the arc shape (R shape) of the arc wall portion 20a is distorted and press-fitted. It is because it can suppress that a load becomes small.

  Next, a method for manufacturing the vibration isolator 100 will be described with reference to FIGS. The vibration isolator 100 is manufactured by first performing a vulcanization process, forming the vulcanized molded body A1, and then moving to a drawing process to perform a drawing process on the vulcanized molded body A1.

  First, the vulcanization process will be described with reference to FIG. 3A is a top view of the vulcanized molded body A1, and FIG. 3B is a cross-sectional view of the vulcanized molded body A1 taken along the line IIIb-IIIb in FIG. 3A.

  In the vulcanization step, first, the inner cylinder member 10 and the outer member 20 are set in a lower mold of a vulcanization mold (not shown), and then the upper mold is moved downward and clamped. Thus, a cavity that is a vulcanization space for vulcanizing the rubber-like elastic body is formed, and the rubber-like elastic body is filled into the cavity by injecting the rubber-like elastic body from the injection hole. Then, by holding the vulcanization mold in a pressurized and heated state for a predetermined time, the rubber-like elastic body (anti-vibration leg portion 31, lower protrusion 32 and membrane portion 33) is vulcanized, and the vulcanized molded body. A1 is molded.

  Here, in the vulcanized molded body A1, one end side of the pair of vibration isolation legs 31 is vulcanized and bonded to the outer peripheral surface of the inner cylinder member 20, and the other end side (base side) is opposed to the outer cylinder member 20. The arc wall portion 20a is vulcanized and bonded to the inner peripheral surface. Moreover, the inner cylinder member 10 is arrange | positioned adjacent to the one linear wall part 20b side because a pair of anti-vibration leg part 31 is formed in the divergent shape.

  After the vulcanization process, the position of the inner cylinder member 10 is moved due to the heat shrinkage of the pair of vibration isolating legs 31, and the straight wall 20b and the inner cylinder on the upper side (the upper side in FIG. 3A) are moved. The clearance with the member 10 is enlarged (the straight portion 34 is widened).

  Next, the drawing process will be described with reference to FIGS. 4 and 5 are top views of the drawing die M1, in which FIG. 4 shows a state before drawing, and FIG. 5 shows a state after drawing. . 4 and 5, the drawing die M1 is schematically illustrated using a two-dot chain line in order to simplify the drawings and facilitate understanding.

  The drawing die M1 is a device for drawing the outer cylinder member 20 of the vulcanized molded body A1, and includes an annular die and an annular holder that holds and guides the annular die from the outer peripheral side. Prepare. The die is divided into a plurality of die pieces M1a and M1b in the circumferential direction, and a taper surface is formed on the outer peripheral surface. The holder has a taper surface corresponding to the taper surface of the die formed on the inner periphery.

  The drawing process is performed by holding the die on a holder installed on the table of the press device, and setting the vulcanized molded body A1 on the inner peripheral side of the die as shown in FIG. Move the die relative to the holder. By such relative movement, the die pieces M1a and M1b are brought closer to each other toward the radially inner side of the vulcanized molded body A1 by the taper surface of the outer peripheral surface being guided by the taper surface of the inner peripheral surface of the holder. The diameter of the die is reduced. As a result, as shown in FIG. 5, the outer cylinder member 20 of the vulcanized molded body A1 is drawn.

  Each die piece M1a, M1b is formed with an engaging portion, and a guide portion that is engaged with the engaging portion is formed on the holder. By the engagement of the engaging portion and the guide portion, Each die piece M1a, M1b is configured to move linearly only in the radial direction. Further, the taper angle of the tapered surface formed on the die (each die piece M1a, M1b) and the holder is set to an angle at which each die piece M1a, M1b moves radially inward at the same speed. Yes.

  Here, the dice includes eight dice pieces M1a and two dice pieces M1b, which are arranged radially. The eight die pieces M1a are brought into contact with the outer peripheral surface of the arc wall portion 20a (see FIG. 3) of the outer cylinder member 20 by pressing the inner peripheral surface thereof, and pressing the arc wall portion 20a radially inward. , A member for reducing the diameter of the arc wall portion 20a, and the inner peripheral surface of each die piece M1a is the outer peripheral surface of the outer cylindrical member 20 after the diameter reduction (that is, the outer cylindrical member 20 in the vibration isolator 100). It is formed in an arc shape with a corresponding radius.

  On the other hand, the die piece M1b mainly contacts the outer peripheral surface of the straight wall portion 20b (see FIG. 3) of the outer cylindrical member 20 and presses the straight wall portion 20b radially inward. The inner peripheral surface of each die piece M1a has a circumferential length that is in contact with both the outer peripheral surface of the straight wall portion 20b and the outer peripheral surface of the arc wall portion 20a of the outer cylinder member 20 (the left-right direction in FIG. 4). Length). The inner peripheral surface of each die piece M1a is formed in a shape corresponding to the outer peripheral surface of the outer cylinder member 20 after the diameter reduction (that is, the outer cylinder member 20 in the vibration isolator 100). That is, the inner peripheral surface of the die piece M1b is a flat surface corresponding to the outer peripheral surface of the straight wall portion 20b, and the arc wall portion 20a is located on both sides (left and right sides in FIG. 4) of the region. A pair of regions formed in an arcuate curved surface corresponding to the outer peripheral surface.

  The vulcanized molded body A1 formed in the vulcanization process is then transferred to the drawing process, and as shown in FIG. 4, the plurality of die pieces M1a and M1b arranged in parallel in the circumferential direction so as to form a radial shape. Set on the peripheral side. And as above-mentioned, each die piece M1a, M1b is displaced toward the radial direction inner side of vulcanization molded object A1 by the pressurization force of a press apparatus, and outer cylinder member 20 of vulcanization molded object A1. The outer peripheral surface is pressed radially inward by the inner peripheral surface of each of the die pieces M1a and M1b.

  As a result, the outer cylinder member 20 has a reduced diameter arc wall portion 20a pressed against the inner peripheral surface of the die piece M1a, and a straight line having both ends (left and right sides in FIG. 4) connected to the arc wall portion 20a. The wall portion 20b is compressed from both ends by the arc wall portion 20a (that is, a load is applied in a direction in which the straight line length of the straight wall portion 20b in the cross-sectional shape perpendicular to the axis is shortened).

  Since the outer peripheral surface of the straight wall portion 20b is in contact with the inner peripheral surface of the die piece M1b and its displacement is restricted, each of the die pieces M1a and M1b is further directed radially inward of the vulcanized molded body A1. When displaced, the straight wall portion 20b compressed from both ends by the arc wall portion 20a and restricted to the outer peripheral surface side by the die piece M1b loses the escape field for plastic deformation, and part thereof Bulge toward the inside in the radial direction. As a result, as shown in FIG. 5, the stopper portion 21 is formed by a portion that bulges toward the inner peripheral surface side of the straight wall portion 20 b.

  As described above, since the stopper portion 21 can be formed in the drawing step, the position of the inner cylinder portion 10 moves downward (downward in FIG. 3) due to the thermal contraction of the pair of vibration-proof leg portions 31. Even when the clearance is enlarged (the straight portion 34 is widened), the formation of the stopper portion 21 ensures an appropriate clearance, and the relative displacement between the inner cylinder member 10 and the outer cylinder member 20 is predetermined. It can be regulated within the range.

  Further, the stopper portion 21 can be formed by drawing the outer cylinder member 20, and unlike the conventional product, it is not necessary to form a bulge or dispose a spacer metal fitting. The part 21 can be formed. In addition, in the vibration isolator 100 which connects the inner cylinder member 10 and the outer cylinder member 20 with the anti-vibration leg part 31, the tensile stress produced inside the anti-vibration leg part 31 by the thermal contraction after vulcanization molding is relieved. Therefore, it is necessary to draw the outer cylinder member 20. Therefore, in the present embodiment, the drawing process for relaxing the tensile stress and the drawing process for forming the stopper portion 21 can be combined. That is, an additional step for forming the stopper portion 21 is not necessary, and an increase in the number of man-hours can be suppressed, so that also in this respect, the manufacturing cost can be reduced.

  Further, while maintaining the state in which the outer peripheral surfaces of the arc wall portion 20a and the straight wall portion 20b of the outer cylinder member 20 are in close contact with the inner peripheral surfaces of the die pieces M1a and M1b, the diameter of the arc wall portion 20a and the straight wall portion are reduced. Since the stopper portion 21 can be formed on 20b, the shape of the arc wall portion 20a can be formed along the inner peripheral shape of the die piece M1a, and the press-fitting load to the bracket member (not shown) can be reduced. Can be secured.

  That is, the stopper portion 21 is formed by pressing a convex die piece corresponding to the shape of the stopper portion 21 from the outer peripheral surface of the straight wall portion 20b of the outer cylinder member 20 in the vulcanized molded body A1. However, in this manufacturing method, the arc wall portion 20a is pulled by the deformation of the straight wall portion 20b, and the arc shape (R shape) of the arc wall portion 20a is bent, so that the press-fitting load is reduced. Even when the inner peripheral surface side of the straight wall portion 20b is held by a jig when pressing with the convex die piece, the arc wall portion 20a cannot be avoided due to the elastic deformation of the film portion 33. On the other hand, when the stopper portion 21 is formed on the outer cylinder member 20 before the vulcanization process, high dimensional accuracy is required for the vulcanization mold in order to ensure the sealing performance in the vulcanization process, and the manufacturing cost increases. On the other hand, as described above, in the present embodiment, since the arc shape of the arc wall portion 20a can be made to conform to the shape of the inner peripheral surface of the die piece M1a, the vibration isolating that can secure the press-fitting load. The device 100 can be manufactured.

  The die piece M1b is formed so that a part of the inner peripheral surface abuts not only on the outer peripheral surface of the straight wall portion 20b but also on the outer peripheral surface of the arc wall portion 20a. It is possible to support (press inward in the radial direction) both the outer peripheral surface and the outer peripheral surface of the arc wall portion 20a with the inner peripheral surface of one die piece M1b. Therefore, the displacement of the arc wall portion 20a and the load from the arc wall portion 20a can be stably transmitted to the straight wall portion 20b without being obstructed by the gap between the die piece M1a and the die piece M1b. Therefore, it can suppress that the deformation | transformation of the straight wall part 20b becomes irregular. As a result, the stopper portion 21 can be reliably formed.

  Next, a second embodiment will be described with reference to FIGS. In 1st Embodiment, although the case where the cross-sectional shape perpendicular | vertical to the axial center before performing the aperture_diaphragm | restriction process of the outer cylinder member 20 was formed in the ellipse shape was demonstrated, the outer cylinder member 220 in 2nd Embodiment is The cross-sectional shape perpendicular to the axial center before the drawing step is formed into a shape in which a part of a circle is divided by a string. In addition, the same code | symbol is attached | subjected to the part same as 1st Embodiment mentioned above, and the description is abbreviate | omitted.

  FIG. 6A is a top view of the vibration isolator 200 according to the second embodiment of the present invention, and FIG. 6B is a cross-sectional view of the vibration isolator 200 taken along the line VIb-VIb in FIG. FIG. In FIG. 6, the shape of each component is schematically illustrated for easy understanding.

  The outer cylinder member 220 is formed in a cylindrical shape from a steel material, and a stopper portion 221 is provided so as to project toward the inner cylinder member 10 from one place on the inner peripheral surface thereof. As in the case of the first embodiment, the stopper portion 221 adjusts the clearance between the inner cylinder member 10 and the outer cylinder member 20, and restricts the relative displacement of both the members 10 and 20 within a predetermined range. It is a part to do. The outer cylinder member 220 is press-fitted and fixed in a press-fitting hole of a bracket member (not shown) that is a member on the vehicle body side. Further, the plate thickness before the outer cylinder member 220 is drawn is set to a thickness dimension equal to or greater than that of the film portion 33.

  Next, the detailed configuration of the outer cylinder member 220 will be described with reference to FIG. 7A is a top view of the outer cylinder member 220, and FIG. 7B is a cross-sectional view of the outer cylinder member 220 taken along the line VIIb-VIIb of FIG. 7A. In addition, the outer cylinder member 220 shown in FIG. 7 illustrates a state before the drawing process is performed by the drawing process. In addition, an extension line of the arc wall portion 20b is schematically illustrated using a two-dot chain line.

  As shown in FIG. 7, the outer cylinder member 220 is a member formed in a cylindrical shape from a steel material, and the cross-sectional shape perpendicular to the axis before performing the drawing step is the axial direction (FIG. ) Formed in the same shape along the vertical direction). Specifically, the cross-sectional shape perpendicular to the axial center of the outer cylinder member 20 is formed into a shape in which a part of a circle is divided by a string.

  That is, the outer cylinder member 20 has an arc wall portion 220a in which a cross-sectional shape perpendicular to the axis before the drawing process is formed in a substantially circular shape, and a cross-sectional shape perpendicular to the axis before the drawing process is linear. And a straight wall portion 220b that divides part of the arc wall portion 220a. In addition, a cross-sectional shape perpendicular to the axial center before the drawing step is formed between the arc wall portion 220a and the straight wall portion 220a in an arc shape having a smaller diameter than the arc wall portion 220a and the arc wall portion 220a. In addition, a connection wall portion 220c inscribed in the straight wall portion 220b is disposed.

  Here, in the outer cylinder member 220, in the cross-sectional shape perpendicular to the axis before the drawing step, the length of the straight wall portion 220b is set to 1/3 of the circumferential length of the arc wall portion 220a and the connection wall portion 220c. It is preferable that the length is shorter than the length and longer than 1/16 of the circumferential length of the arc wall portion 20a and the connection wall portion 220c. By making it shorter than 1/3 of the circumferential length, the length (circumferential length) of the arc wall portion 220a can be secured in the drawing step, and the straight wall portion 220b can be sufficiently compressed from both ends, and the stopper This is because the bulging portion as the portion 221 (see FIG. 6) can be reliably formed and the length of the straight wall portion 220b is excessively large, and the deformation thereof can be suppressed. . On the other hand, by making it longer than 1/16 of the circumferential length, when the bulging portion as the stopper portion 221 is formed by compressing the straight wall portion 220b from both ends by the arc wall portion 220a in the drawing step, When the length of the straight wall portion 220b is insufficient and the arc wall portion 220a is pulled by the deformation (bulge) of the straight wall portion 220b, the arc shape (R shape) of the arc wall portion 220a is distorted and press-fitted. It is because it can suppress that a load becomes small. In addition, the radius of the connection wall part 220c is a deformation (for example, a radius of 1/5 to 1/20) sufficiently smaller than the radius of the arc wall part 220a.

  Next, a method for manufacturing the vibration isolator 200 will be described with reference to FIGS. As in the case of the first embodiment, the vibration isolator 200 is manufactured after the vulcanized molded body A2 is formed by the vulcanization process, and then the drawing process is performed, and the vulcanized molded body A2 is drawn. Is done. Since the vulcanization step and the vulcanized molded body A2 formed by the vulcanization step are the same as those in the first embodiment, description thereof is omitted.

  8 and 9 are top views of the drawing mold M2, in which FIG. 8 shows a state before drawing, and FIG. 9 shows a state after drawing. . In FIG. 8 and FIG. 9, the drawing die M2 is schematically illustrated using a two-dot chain line in order to simplify the drawing and facilitate understanding.

  The drawing die M2 is a device for drawing the outer cylinder member 220 of the vulcanized molded body A2, and as in the case of the first embodiment, an annular die and the annular die are arranged on the outer peripheral side. And an annular holder for holding and guiding. The die is divided into a plurality of die pieces M2a and M2b in the circumferential direction, and a tapered surface is formed on the outer peripheral surface. The holder has a tapered surface corresponding to the tapered surface of the die formed on the inner periphery.

  As shown in FIG. 8, after the vulcanized molded body A2 is set on the inner peripheral side of the die, as shown in FIG. 9, a method of drawing the outer cylinder member 220 of the vulcanized molded body A2 and the drawing The configuration of the mold M2 is the same as in the case of the first embodiment, and a description thereof will be omitted. Further, the configuration in which each die piece M2a, M2b moves linearly only in the radial direction and the configuration in which each die piece M2a, M2b moves at the same speed are the same as in the case of the first embodiment. Therefore, the description is omitted.

  Here, in the second embodiment, the dice includes nine dice pieces M2a and one dice piece M2b, which are arranged radially. The nine die pieces M2a have their inner peripheral surfaces in contact with the outer peripheral surface of the arc wall portion 220a (see FIG. 7) of the outer cylindrical member 220, and press the arc wall portions 220a radially inward. , A member for reducing the diameter of the arc wall portion 220a, and the inner peripheral surface of each die piece M2a is the outer peripheral surface of the outer cylindrical member 220 after the diameter reduction (that is, the outer cylindrical member 220 in the vibration isolator 200). It is formed in an arc shape with a corresponding radius.

  On the other hand, the die piece M2b is a member that mainly abuts the inner peripheral surface of the die piece M2b on the outer peripheral surface of the straight wall portion 220b (see FIG. 7) of the outer cylindrical member 220 and presses the straight wall portion 220b radially inward. The inner peripheral surface of each die piece M2a has a circumferential length that is in contact with both the outer peripheral surface of the straight wall portion 220b of the outer cylinder member 220 and the outer peripheral surface of the connection wall portion 220c (the horizontal direction in FIG. 8). Length). In addition, the inner peripheral surface of each die piece M2a is formed in a shape corresponding to the outer peripheral surface of the outer cylinder member 220 after the diameter reduction (that is, the outer cylinder member 220 in the vibration isolator 200). In other words, the inner peripheral surface of the die piece M2b is a flat surface corresponding to the outer peripheral surface of the straight wall portion 220b, and is located on both sides (left and right sides in FIG. 7) of the region. A pair of regions formed in an arcuate curved surface corresponding to the outer peripheral surface.

  The vulcanized molded body A2 formed in the vulcanization process is transferred to the drawing process, and as shown in FIG. 8, the inner periphery of a plurality of die pieces M2a and M2b arranged in parallel in the circumferential direction so as to form a radial shape. Set on the face side. Then, as in the case of the first embodiment, each die piece M2a, M2b is displaced toward the inside in the radial direction of the vulcanized molded body A2 by the pressurizing force of the press device. The outer peripheral surface of the outer cylindrical member 220 of A2 is pressed radially inward by the inner peripheral surfaces of the die pieces M2a and M2b.

  As a result, the outer cylindrical member 220 is reduced in diameter by the arc wall portion 220a pressed against the inner peripheral surface of the die piece M2a, and both ends (on the left and right sides in FIG. 7) are connected to the arc wall portion 220a. The straight wall portion 220b connected via the arc is compressed from both ends by the circular arc wall portion 220a and the connecting wall portion 220c (that is, the straight line length of the straight wall portion 220b in the cross-sectional shape perpendicular to the axial center is shortened). Receiving load in the direction). In this case, the connecting wall portion 220c is also pressed and reduced in diameter by the inner peripheral surface of the die piece M2b.

  Since the outer peripheral surface of the straight wall 220b is in contact with the inner peripheral surface of the die piece M2b and its displacement is restricted, each of the die pieces M2a and M2b is further directed inward in the radial direction of the vulcanized molded body A2. When displaced, the linear wall part 220b compressed by the arc wall part 220a from both ends through the connection wall part 220c and restricted to the outer peripheral surface side by the die piece M2b is a refuge for plastic deformation. Is lost, and a part of it is expanded radially inward. As a result, as shown in FIG. 9, the stopper portion 221 is formed by a portion formed by bulging toward the inner peripheral surface side of the straight wall portion 220 b.

  As described above, since the stopper portion 221 can be formed in the drawing step, the clearance is expanded due to the thermal contraction of the pair of vibration-proof leg portions 31 as in the case of the first embodiment ( Even when the straight portion 34 is widened), by forming the stopper portion 221, an appropriate clearance can be secured and the relative displacement of the inner cylinder member 10 and the outer cylinder member 220 can be regulated within a predetermined range.

  In addition, since the stopper portion 221 can be formed by drawing the outer cylinder member 220, the stopper portion 221 can be formed while suppressing the manufacturing cost as in the case of the first embodiment. it can. In addition, as in the case of the first embodiment, the drawing process for reducing the tensile stress and the drawing process for forming the stopper portion 221 can be combined to reduce the manufacturing cost. It is.

  While maintaining the outer peripheral surface of the arc wall portion 220a of the outer cylinder member 220, the outer peripheral surface of the straight wall portion 220b and the outer peripheral surface of the connection wall portion 220c in close contact with the inner peripheral surface of the die pieces M2a, M2b, Since the arc wall 220a and the connecting wall 220c can be reduced in diameter and the stopper 221 can be formed on the straight wall 220b, the arc wall 220a and the connecting wall can be formed in the same manner as in the first embodiment. The shape of the portion 220c can be formed in a shape along the inner peripheral shape of the die pieces M2a and M1a, and a press-fitting load to a bracket member (not shown) can be ensured.

  The die piece M2b is formed so that a part of the inner peripheral surface is in contact with not only the outer peripheral surface of the straight wall portion 220b but also the outer peripheral surface of the connection wall portion 220c. It is possible to support (press inward in the radial direction) both the outer peripheral surface and the outer peripheral surface of the connection wall 220c with the inner peripheral surface of one die piece M2b. Therefore, the displacement of the arc wall part 220a and the connection wall part 220c and the load from the arc wall part 220a and the connection wall part 220c are set between the die piece M2a and the die piece M2b as in the case of the first embodiment. Since it can be stably transmitted to the straight wall portion 220b without being obstructed by the gap, it is possible to suppress irregular deformation of the straight wall portion 220b. As a result, the stopper portion 221 can be reliably formed.

  Further, in the present embodiment, the cross-sectional shape perpendicular to the axial center before the outer cylinder member 220 is squeezed is formed into a shape in which a part of a circle is divided by a string (see FIG. 7). In the squeezing step, the length of the arc wall portion 220a can be secured and the straight wall portion 220b can be sufficiently compressed from both ends, so that the stopper member 221 can be formed reliably and the arc wall portion 220a. By forming a circular shape as a whole, the shape of the arc wall portion 220a can be easily formed along the inner peripheral shape of the die piece M2a, and the press-fitting load to the bracket member (not shown) can be reliably ensured.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. It can be easily guessed.

  The numerical values given in the above embodiments are merely examples, and other numerical values can naturally be adopted. In addition, it is naturally possible to apply a part or all of the components described in the above embodiments to other embodiments.

  In each of the above embodiments, the case where the entire outer peripheral surface of the outer cylinder member 20, 220 is formed in parallel along the axis has been described. However, the present invention is not necessarily limited to this, and a part of the outer peripheral surface is formed. It may be formed in a tapered shape. In this case, in the drawing step, drawing may be performed only on a portion parallel to the axial center of the outer peripheral surface of the outer cylindrical member 20, or a portion formed in a tapered shape in addition to the portion parallel to the axial center. Alternatively, the same drawing process as in the above embodiments may be applied.

  In each of the above-described embodiments, the case where the pair of anti-vibration legs 31 is formed in the shape of a widening from the inner cylinder member 10 toward the outer cylinder member 20, 220 is not necessarily limited to this. Of course, other shapes are possible. For example, the pair of vibration isolation legs 31 may be formed in a straight line.

  In each of the above-described embodiments, the case where each of the die pieces M1a and M1b and each of the die pieces M2a and M2b moves radially inward at the same speed has been described. However, the present invention is not necessarily limited to this. Of course, it is possible for some of the die pieces to move at a different speed than the other die pieces.

  In the first embodiment, the case has been described in which the inner peripheral surface of the die piece M1b is formed to have a width dimension that contacts both the outer peripheral surface of the straight wall portion 20b and the outer peripheral surface of the arc wall portion 20a. However, the present invention is not necessarily limited to this, and the width dimension of the inner peripheral surface of the die piece M1b may be a dimension that contacts only the outer peripheral surface of the straight wall portion 20b. In this case, the width dimension of the inner peripheral surface of the die piece M1a adjacent to the die piece M1b is defined as the width dimension in which the inner peripheral surface is in contact with both the outer peripheral surface of the arc wall portion 20a and the outer peripheral surface of the linear wall portion 20b. Also good.

  Similarly, in the second embodiment, the inner peripheral surface of the die piece M2b is formed to have a width dimension that contacts both the outer peripheral surface of the straight wall portion 220b and the outer peripheral surface of the connection wall portion 220c. However, the present invention is not necessarily limited to this, and the width dimension of the inner peripheral surface of the die piece M2b may be a dimension that contacts only the outer peripheral surface of the straight wall portion 220b, or the inner periphery of the die piece M2b. The width dimension of the surface may be a width dimension that abuts on each of the outer peripheral surface of the straight wall portion 220b, the outer peripheral surface of the connection wall portion 220c, and the outer peripheral surface of the arc wall portion 220a. On the other hand, the width dimension of the inner peripheral surface of the die piece M2a adjacent to the die piece M2b may be the width dimension in which the inner peripheral surface is in contact with both the outer peripheral surface of the arc wall portion 20a and the outer peripheral surface of the connection wall portion 220c. The width dimension of the inner peripheral surface of the die piece M2a adjacent to the die piece M2b is good, and the inner peripheral surface is the outer peripheral surface of the arc wall portion 20a, the outer peripheral surface of the connection wall portion 220c, and the outer peripheral surface of the straight wall portion 220b. It is good also as a width dimension which contacts each surface.

100, 200 Vibration isolator 10 Inner cylinder member 20 Outer cylinder member 20a, 220a Arc wall part 20b, 220b Straight wall part 220c Connection wall part (part of arc wall part)
31 Anti-vibration legs 21 and 221 Stopper (stopper member)
A1, A2 Vulcanized moldings M1, M2 Die dies M1a, M1b Die pieces M2a, M2b Dice pieces

Claims (4)

An inner cylinder member formed in a cylindrical shape, an outer cylinder member disposed on the outer peripheral side of the inner cylinder member and formed in a cylindrical shape from a metal material, and the inner cylinder located between the inner cylinder member A pair of anti-vibration legs that connect the outer peripheral surface of the member and the inner peripheral surface of the outer cylinder member and are formed of a rubber-like elastic body; and the inner cylinder disposed on the inner peripheral surface side of the outer cylinder member In the manufacturing method of the vibration isolator for manufacturing the vibration isolator including the stopper member that restricts the relative displacement between the member and the outer cylinder member,
An outer peripheral surface of the inner cylinder member is formed by the pair of vibration-proof legs by injecting a rubber-like elastic body into a cavity of a vulcanization mold in which the inner cylinder member and the outer cylinder member are installed. And a vulcanization step of forming a vulcanized molded body in which the inner peripheral surface of the outer cylinder member is connected,
The vulcanized molded body molded by the vulcanization step is placed in a drawing die having a plurality of die pieces arranged in a circumferential direction so as to form a radial shape, and the plurality of die pieces are vulcanized and molded. A drawing step of drawing the outer cylinder member of the vulcanized molded body by displacing the body inward in the radial direction,
The outer cylinder member includes one or a plurality of arc wall portions in which a cross-sectional shape perpendicular to the axis before the drawing step is formed in an arc shape, and a cross section perpendicular to the axis before the drawing step One or a plurality of straight wall portions formed in a straight line shape,
In the vulcanization step, the vulcanized molded body connected to the circular arc wall portion in a state where the pair of vibration-proof leg portions sandwich the straight wall portion of the outer cylinder member,
In the drawing step, the arc wall portion is reduced in diameter, and a part of the linear wall portion is bulged inward in the radial direction, and the stopper member is formed by the bulged portion. A method for manufacturing a vibration isolator.   The outer cylinder member is characterized in that, in a cross-sectional shape perpendicular to the axis before performing the drawing step, the length of the straight wall portion is shorter than half the circumference of the arc wall portion. A method for manufacturing a vibration isolator according to claim 1.   The outer cylinder member has a cross-sectional shape perpendicular to the axis before the drawing step, and both ends of the straight wall portion are connected to a circumferential end of the arc wall portion, and the axial center The method for manufacturing a vibration isolator according to claim 1 or 2, wherein a cross-sectional shape perpendicular to the cross section is formed into a shape in which a part of a circle is divided by a string.   The drawing step is formed such that an inner peripheral surface of at least one of the plurality of die pieces comes into contact with an outer peripheral surface of the straight wall portion and an outer peripheral surface of the arc wall portion. The method for manufacturing a vibration isolator according to any one of claims 1 to 3, wherein the drawing tool is used to draw the outer cylinder member of the vulcanized molded body.

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