JP5654913B2 - Manufacturing method of cylindrical anti-vibration rubber with flange - Google Patents

Description

  The present invention relates to a method for manufacturing a flanged cylindrical vibration-proof rubber, and more particularly to a manufacturing method characterized by a drawing technique.

As a typical example of this kind of cylindrical vibration-proof rubber, there is a member mount that elastically connects a suspension member of a vehicle and a vehicle body.
A suspension member such as a subframe is a partial skeletal member of a vehicle for mounting the suspension, and the suspension is assembled to the vehicle body via the suspension member.

The member mount elastically connects the suspension member and the vehicle body. In this case, the member mount maintains the relative positional relationship between the suspension member and the vehicle body correctly, and the suspension system is transmitted to the vehicle body via the suspension member. It also functions to transmit the driving force and braking force to the vehicle body.
In the case of the subframe, an engine, a transmission, and the like are attached in addition to the suspension. In this case, the member mount that elastically connects the subframe and the vehicle body also cuts off vibrations from the engine.

In general, this kind of member mount is a cylindrical rigid inner cylinder member, an outer cylinder fitting that surrounds the inner cylinder member at a position spaced in the radial direction, and elastically connects the inner cylinder member and the outer cylinder fitting in the radial direction. It has a cylindrical rubber elastic body that is integrally vulcanized and bonded to the state, and is fixed to the suspension member in the outer cylinder fitting and to the vehicle body in the inner cylinder member, so that the suspension member and the vehicle body are elastic. Connects and acts as a vibration isolator.
In this cylindrical member mount, after the rubber elastic body is integrally vulcanized together with the inner cylinder member and the outer cylinder fitting, the outer cylinder fitting is pressed radially inward from the outer peripheral surface side using a drawing die, Drawing is performed to reduce the diameter.

  The drawing process after this vulcanization process pre-compresses the rubber elastic body, thereby removing the shrinkage stress after vulcanization of the rubber elastic body. The purpose is to increase the durability by preventing the tensile stress from acting on the body.

In general, as a member mount, a rubber elastic body is provided with a pair of straight portions at positions opposed to each other in the direction perpendicular to the axis with the inner cylinder member in between in order to make the spring characteristics different between the longitudinal direction and the lateral direction of the vehicle. Is used.
In this way, when a pair of straight portions are provided at positions opposed to the direction perpendicular to the axis of the rubber elastic body, there is a problem that if the drawing is performed after the vulcanization process, the shape becomes elliptical.

  The rubber reaction force generated by the drawing process is small in the direction connecting the straight part and the straight part (this is the X direction), while the rubber reaction force generated by the drawing process is perpendicular to the direction (Y direction). In the X direction, the rigidity of the outer cylinder bracket overcomes the rubber reaction force. In the Y direction, the rubber reaction force overcomes the rigidity of the outer cylinder bracket and deforms it. Shape) becomes an oval shape as a whole together with the rubber elastic body. Specifically, the shape is deformed into an elliptical shape with the X direction as the short axis and the Y direction as the long axis.

  For the purpose of solving the above-mentioned problem of elliptical shape that occurs in a cylindrical anti-vibration rubber having a straight portion at a position facing the direction perpendicular to the axis of the rubber elastic body with the inner cylinder member in between, the following patent document 1 , Patent Document 2 adds a drawing die having an elliptical inner peripheral surface shape, more specifically, a drawing die having an elliptical shape in which the diameter in the X direction is the major axis and the diameter in the Y direction is the minor axis. The point which performs the drawing process after sulfur is disclosed.

By the way, when the outer cylinder fitting has a flange portion projecting radially outward on one axial end side, the rigidity of the outer cylinder fitting is greatly increased from the axial end on the flange portion side to the opposite axial end. Change to small.
Along with the change in the rigidity, there arises a difficult problem that the degree of the elliptical shape is different in the axial direction.

  In this case, the degree of ovalization becomes the largest at the end of the axial direction opposite to the flange portion where the rigidity of the bracket is the smallest, and the end of the axial direction opposite to the flange portion is the member. It is a portion that becomes a press-fitting side end when the mount is press-fitted into a cylindrical holder. If the portion is greatly elliptical, press-fitting into the holder becomes difficult, and press-fitting becomes impossible in some cases.

  Although the member mount has been described above, even in a general flanged cylindrical anti-vibration rubber, the above-mentioned elliptical shape makes it difficult or impossible to press-fit into the mating cylindrical press-fit portion. Arise.

JP 2007-224987 A Japanese Patent Laid-Open No. 2002-301531

  The present invention is based on the above circumstances, and the outer cylinder fitting is provided with a flange, and even if the rigidity changes along the axial direction, the oval shape by the diaphragm is good over the entire axial direction. The object of the present invention is to provide a manufacturing method of a flanged cylindrical vibration-proof rubber that can be suppressed to a perfect circle shape.

Thus, the manufacturing method of claim 1 comprises a cylindrical rigid inner cylinder member and a flange portion projecting radially outward on one end side in the axial direction surrounding the inner cylinder member at a position spaced apart in the radial direction. And a cylindrical outer cylinder fitting having a cylindrical shape, and a vulcanized and bonded integrally in a state where the inner cylinder member and the outer cylinder fitting are elastically connected to each other. possess a rubber elastic body having a cylindrical shape provided with the parts, and the outer peripheral surface of the outer cylinder metal fitting, the state of projecting a strip rubber portions extending annularly around the axis of the outer tubular member from the outer peripheral surface A flanged cylindrical anti-vibration rubber fixed in a plurality of positions at intervals in the axial direction is formed by (a) vulcanizing and molding the rubber elastic body, and integrally adding the inner cylindrical member and the outer cylindrical metal fitting. (B) after the vulcanization step, the outer tube metal is drawn using a drawing die. A method for producing a flanged tubular vibration-proof rubber manufactured by pressing a tool radially inward from the outer peripheral surface side and reducing the diameter, and in the drawing process in the drawing process, As a drawing die, the shape of the inner peripheral surface of the metal member pressing portion that directly contacts and presses the outer tube metal member, excluding the portion that presses the end on the flange portion side, is opposed to the direction perpendicular to the axis. The elliptical shape has a major axis that is the diameter in the X direction connecting the corner part and the corner part, and a minor axis that is the direction perpendicular to the axis and the Y direction perpendicular to the X direction. The difference is ellipticity, and the ellipticity changes from small to large from the axial end on the flange portion side to the axial end on the opposite side, and the band shape of the inner peripheral surface of the drawing die At multiple locations in the axial direction corresponding to the rubber part, radially outward The fitting pressing portion that has a rubber pressing portion that presses the belt-shaped rubber portion that has a recessed shape and that directly presses the outer peripheral surface of the outer cylindrical fitting at a position between the rubber pressing portion and the rubber pressing portion is pivoted. The metal fitting pressing portion is formed in a straight shape in the axial direction of the outer cylinder fitting, and is directed from the axial end on the flange side to the opposite axial end for each fitting pressing portion. Thus, the drawing is performed using a drawing die having a shape in which the ellipticity changes stepwise from small to large .

According to a second aspect of the present invention, in the first aspect , the cylindrical vibration isolating rubber is a member mount that elastically connects a suspension member of a vehicle and a vehicle body.

Effects and effects of the invention

  As described above, according to the present invention, in the drawing process in the drawing process, as the drawing die, the shape of the inner peripheral surface of the metal fitting pressing portion has a long diameter in the X direction connecting the straight portion and the straight portion, and is orthogonal thereto. Using an aperture die having a shape in which the diameter in the Y direction is the minor axis, and the ellipticity changes from small to large from the axial end on the flange side toward the opposite axial end Drawing processing is performed.

  According to the present invention, even if the rigidity of the outer cylinder fitting changes along the axial direction, the cross-sectional shape of the outer cylinder fitting and the rubber elastic body inside thereof is elliptical over the entire axial length. It is possible to suppress this well, and at any position in the axial direction, the cross-sectional shape can be made close to a perfect circle.

In particular, the present invention is directed to a flanged cylindrical vibration-proof rubber having a configuration in which a band-like rubber portion extending annularly around its axis is fixed to a plurality of locations at intervals in the axial direction on the outer peripheral surface of an outer cylindrical metal fitting. It relates to a manufacturing method.

The band-like rubber portion on the outer peripheral surface of the outer cylinder fitting is provided for the purpose of enhancing the press-fitting property when the cylindrical vibration-proof rubber is press-fitted into the press-fitting portion on the other side.
By applying and impregnating this band-shaped rubber part with oil, the resistance at the time of press-fitting can be reduced and the press-fitting property can be improved.
On the other hand, after the press-fitting, the removal force can be increased by removing the oil by drying.

In the present invention , in correspondence with the provision of such a band-shaped rubber part, a rubber pressing part that presses the band-shaped rubber part is formed on the inner peripheral surface of the drawing die so as to form a concave shape radially outward. .
And the metal fitting press part which presses the outer peripheral surface of an outer cylinder metal fitting directly in the position between a rubber press part and a rubber press part is provided in the several places of an axial direction.

  In this case, if the shape of the inner peripheral surface of the metal fitting pressing part is a shape that continuously changes the ellipticity in the axial direction, that is, the inclination of the shape of the inner peripheral surface inclined with respect to the axial direction of the outer cylindrical metal fitting. If it becomes a surface, it will press an outer cylinder metal fitting in the corner | angular part which protruded to the outer cylinder metal fitting side of the metal fitting press part. In other words, the outer cylinder fitting is squeezed only at the corners.

Therefore, in the present invention , the shape of the inner peripheral surface of the metal fitting pressing portion is a straight shape in the axial direction of the outer cylindrical metal fitting, and for each metal fitting pressing portion, from the axial end on the flange side to the axial end on the opposite side. A shape in which the ellipticity gradually changes from small to large.
Thereby, it can avoid favorably that a metal fitting press part will press an outer cylinder metal fitting at the corner | angular part which approached the near side of the outer cylinder metal fitting.

The present invention is generally applicable to a flanged cylindrical vibration-proof rubber, and is particularly suitable for manufacturing a member mount that elastically connects a suspension member of a vehicle and a vehicle body (claim 2 ).

It is the figure which showed the member mount as an example of the application object of this invention in the vehicle assembly | attachment state. It is a longitudinal cross-sectional view of the member mount. It is sectional drawing and the bottom view of the same axis direction of the member mount. It is the figure which showed the drawing die for drawing processing used with the manufacturing method of embodiment of this invention. It is a figure which shows the longitudinal cross-sectional shape of the inner peripheral part of the aperture die of FIG. It is the figure which showed typically the shape of the inner peripheral part in the position where the axial direction of the aperture_diaphragm | die of FIG. 4 differs. It is the figure which showed the principal part process of the manufacturing method of the embodiment. It is the figure which showed typically the deformation | transformation of the outer cylinder metal fitting at the time of drawing using a perfect circle-shaped drawing die as a comparative example. It is the figure which showed typically the comparative example for demonstrating the advantage of embodiment of this invention.

Next, embodiments of the present invention will be described in detail with reference to the drawings.
In FIG. 1, reference numeral 10 denotes a vehicle body side member having a panel shape, 12 a cylindrical holder fixed to a subframe (well-shaped subframe) as a suspension member, and 14 a subframe and a vehicle body via the holder 12. A member mount (cylindrical vibration-proof rubber) that elastically connects the side members 10 and performs vibration-proofing action between them.
The holder 12 has a flange portion 13 projecting radially outward (annular shape here) radially outward on one end side in the axial direction (lower end side in the figure), and a member mount 14 is press-fitted inside. It has a holding hole 16 for holding it.

Reference numeral 18 denotes an upper stopper, which has a plate-like and annular holding bracket 20 that is overlapped with the vehicle body side member 10 in the assembled state, and a stopper rubber portion 22 that is vulcanized and bonded integrally thereto and falls downward. doing.
Here, the stopper rubber portion 22 has an annular shape (in plan view), and abuts against the stopper contact portion 24 of the holder 12 to perform a stopper action.
Here, the stopper contact portion 24 is formed by a radially inward flange portion at the upper end of the holder 12 in the drawing.

  Reference numeral 26 denotes a metal stopper plate which forms a main part of the lower stopper 28. The stopper plate 26 pivots an inner cylinder fitting (inner cylinder member) 40 described later of the member mount 14 together with the holding fitting 20 of the upper stopper 18. A central annular portion 30 sandwiched in the direction, a tapered portion 32 falling from the outer peripheral edge of the sandwiched portion 30, and an annular stopper extending in the radial direction (perpendicular to the axis) following the tapered portion 32 And a contact portion 34.

  The member mount 14 is press-fitted into the holding hole 16 of the holder 12 in an outer cylinder fitting 42 which will be described later, and while being held there, the member mount 14 is inserted through the inner cylinder fitting 40 to fasten the stopper plate 26 and the vehicle body side member 10. The fastening bolt 36 and the nut 38 are assembled to the vehicle body side member 10 together with the subframe.

As shown in FIGS. 2 and 3, the member mount 14 includes a cylindrical rigid inner tube fitting 40, a cylindrical rigid outer tube fitting 42 that surrounds the cylindrical mount 40 in a radially separated position, and It has a cylindrical rubber elastic body 44 connected in the radial direction.
Here, the rubber elastic body 44 is integrally vulcanized and bonded to the inner cylinder fitting 40 and the outer cylinder fitting 42.

The outer cylinder fitting 42 has a main body portion 46 extending in a straight shape in the vehicle vertical direction, that is, the vertical direction in FIG. 2, and an annular (here circular) flange portion 48 projecting radially outward at the lower end thereof. doing.
On the other hand, the rubber elastic body 44 is formed continuously with the cylindrical main body rubber portion 50 sandwiched in the radial direction between the inner tube fitting 40 and the main body portion 46 of the outer tube fitting 42, and is formed on the outer tube fitting 42. A stopper rubber portion 52 is formed on the lower surface of the flange portion 48 and falls downward.
The stopper rubber portion 52 abuts on the stopper contact portion 34 of the stopper plate 26 to perform a stopper action.
The lower stopper 28 in FIG. 1 includes the stopper rubber portion 52 and the stopper plate 26.
The rubber elastic body 44 further includes a covering rubber portion 54 that covers the flange portion 48 of the outer tube fitting 42.

As shown in FIG. 3, the rubber elastic body 44, specifically, the main body rubber portion 50, is provided with a pair of straight portions 56 at positions facing each other in the direction perpendicular to the axis with the inner cylinder fitting 40 interposed therebetween.
The pair of straight portions 56 are arranged in the vehicle front-rear direction with the inner cylindrical fitting 40 interposed therebetween.
Each of the pair of straight portions 56 and 56 has a substantially arc shape, and is provided in a vertically symmetrical position and in a vertically symmetrical shape in the drawing.
These straight portions 56 are respectively provided in a form that penetrates the rubber elastic body 44 in the axial direction as shown in FIG.

On the other hand, on the outer peripheral surface of the outer cylindrical fitting 42, belt-like rubber portions 58-1, 58-2, 58-3 extending annularly around the entire axis are fixed at a plurality of positions with an interval in the axial direction. Yes.
These band-like rubber portions 58-1, 58-2, 58-3 are also integrally vulcanized and bonded to the outer cylinder fitting 42.

Here, the belt-like rubber portions 58-1 to 58-3 are provided for the purpose of improving the press-fitting property when the member mount 14 is press-fitted into the holder 12, respectively.
Specifically, the member mount 14 can be easily inserted into the holder 12 with a small resistance by applying and absorbing oil to the belt-like rubber portions 58-1 to 58-3.
On the other hand, the oil is removed by subsequent drying, so that the force with which the member mount 14 is removed from the holder 12 can be increased.

  The member mount 14 is formed by vulcanizing and molding the rubber elastic body 44 in the vulcanization process, and by integrally vulcanizing and bonding the inner cylinder metal fitting 40 and the outer cylinder metal fitting 42 to the outer cylinder surface 42 in the drawing process. It is manufactured by pressing inward in the radial direction from the side and performing drawing to reduce the diameter.

Thus, when a drawing die having a perfect circular inner peripheral surface is used as the drawing die, the shapes of the outer cylinder fitting 42 and the rubber elastic body 44 (transverse cross-sectional shape) are deformed into an elliptical shape. .
Moreover, when the difference between the major axis and the minor axis is defined as ellipticity, the ellipticity varies depending on the position in the axial direction.
Specifically, the ellipticity changes from small to large from the axial end (lower end in the figure) of the outer cylinder fitting 42 toward the opposite axial end (upper end in the figure).

FIG. 8 schematically illustrates this.
FIG Lt., an elliptical shape that occurs in the axial position P ₄ in FIG. 2, b is an elliptical shape that occurs in Figure 2 the inner shaft direction position P _3, Ha an elliptical shape results in Figure 2 the inner shaft direction position P _2, also d is each schematically represent a elliptical shape that occurs in Figure 2 the center shaft direction position P _1.

  As shown in the figure, the outer cylinder fitting 42 and the rubber elastic body 44 have the X direction in the direction connecting the straight portions 56 and 56 (strictly, the direction connecting the respective circumferential centers of the straight portions 56 and 56). When the direction perpendicular to this is the Y direction, it is deformed into an elliptical shape having the X direction as the short axis and the Y direction as the long axis.

  This is because when the outer cylinder fitting 42 is drawn using a drawing die, the rubber reaction force is small in the X direction and the rubber reaction force is large in the Y direction. As a result, the rigidity of the outer cylinder fitting 42 is Y This is because the outer cylinder fitting 42 is deformed so as to bulge outward in the Y direction by losing the rubber reaction force in the direction.

In addition, as the axial position changes from P ₄ → P ₃ → P ₂ → P ₁ , the elliptical shape changes from i → b → c → d and the ellipticity changes from small to large. This is because the rigidity of the outer cylinder fitting 42 is the highest on the flange portion 48 side, and the rigidity decreases as it advances toward the opposite axial end, and the force for resisting the rubber reaction force and maintaining the shape becomes weak.

  Therefore, in this embodiment, the shape of the inner peripheral surface of the metal fitting pressing parts 64-1, 64-2, 64-3 (see FIG. 5), which will be described later, is used as the drawing die for drawing, and the diameter in the X direction is the same. An aperture die having an elliptical shape having a major axis and a minor axis in the Y direction, and whose ellipticity changes from small to large from the axial end on the flange 48 side to the opposite axial end. Is used for drawing.

In FIG. 4, 60 represents the aperture die.
Here, the drawing die 60 is equally divided into 16 die pieces 60h.
As shown in FIG. 6, the shape of the inner peripheral surface (specifically, the shape of the inner peripheral surface of the metal fitting pressing portions 64-1, 64-2, 64-3) is the same as the elliptical shape shown in FIG. Has a reverse elliptical shape in which the minor axis and the major axis are reversed, and the ellipticity changes from small to large from the axial end on the flange portion 48 side to the opposite axial end. .

In FIG. 6, b is an oval shape in the axial direction position P ₃ in FIG. 2, c is an elliptic shape in the axial direction position P ₂ in FIG. 2, also d is an elliptical shape in the axial position P ₁ in FIG. 2, respectively This is shown schematically.
Note a represents the shape of the inner peripheral surface of the drawing die 60 in the axial direction position P ₄ in FIG. 2, the shape of a here is a true circle.
This is because the flange portion 48 in the axial position P ₄ the rigidity of the outer tubular member 42 is in the high rigidity, here dare without the inner peripheral surface of the shape perfect circular drawing die 60 at the same position ing. However the shape of the inner peripheral surface of the drawing die 60 in the axial direction position P _4, be left without a small elliptical shape of the elliptical degree is also possible as well.

As described above, in this embodiment, in the portion that generates an elliptical shape with a large ellipticity in FIG. 8, the relationship between the major axis and the minor axis is reversed and an elliptical shape with a large ellipticity (reverse elliptical shape) is obtained. In addition, with respect to a portion that generates an elliptical shape with a small ellipticity, the shape of the inner peripheral surface of the aperture die 60 in FIG. 4 is different in the axial direction so as to correspond to the elliptical shape with a small ellipticity. In advance.
Note that the peripheral lengths of the inner peripheral surfaces of the dice 60 at P ₁ , P ₂ , P ₃ , and P ₄ in FIG. 2 are made uniform.

FIG. 5 shows a vertical cross-sectional shape of the inner peripheral portion of the die 60.
4A is the BB cross section of FIG. 4, that is, the shape of the vertical cross section cut in the Y direction, and FIG. 4B is the CC cross section of FIG. 4, ie, the vertical cross section cut in the X direction. The shape is shown.
In these figures, 62-1, 62-2 and 62-3 respectively press the belt-like rubber portions 58-1, 58-2 and 58-3 in FIG. These rubber pressing portions 62-1, 62-2 and 62-3 are used to press the rubber-like rubber portions 58-1, 58-2 and 58-3 inserted into the respective rubber pressing portions 62-1, 62-2 and 58-3. To do.
On the other hand, 64-1, 64-2, 64-3, and 64-4 are metal fittings that directly press the outer tube fitting 42 at the respective positions P ₁ , P ₂ , P ₃ , P ₄ in the axial direction of FIG. It is a pressing part.

Here, the relationship between the diameters DY ₁ , DY ₂ , DY ₃ , and DY ₄ in the Y direction (short axis side) in FIG. 5A is DY ₁ <DY ₂ <DY ₃ <DY ₄ .
In other words, the diameter of the outer cylinder fitting 42 is gradually reduced from the axial end on the flange portion 48 side toward the opposite axial end.
Here, DY ₁ , DY ₂ , and DY ₃ are diameters (short diameters) on the minor axis side in an elliptical shape (reverse elliptical shape), and DY ₄ is a diameter in a perfect circular shape.

On the other hand, the relationship between the diameters DX ₁ , DX ₂ , DX ₃ , DX ₄ in the X direction in FIG. 5B is DX ₁ > DX ₂ > DX ₃ > DX ₄ .
That is, the diameter gradually increases from the axial end on the flange portion 48 side to the opposite axial end.
Here, DX ₁ , DX ₂ , DX ₃ are the major axis diameters (major axis) in the elliptical shape (reverse elliptical shape), and DX ₄ is the diameter in the perfect circle shape.
Accordingly, the dimensions DY ₄ and DX _{4 at the} axial position P ₄ closest to the flange portion 48 side indicate the diameter of a perfect circle and are equal to each other.
Specifically, here, DY ₄ = DX ₄ = φ78 mm.
However, as described above, DX ₄ may be larger than DY ₄ .
The rubber pressing portions 62-1 to 62-3 are all formed in a perfect circle shape with a diameter D here.

In this embodiment, the metal pressing parts 64-1, 64-2, 64-3, and 64-4 have a pressing surface that is straight in the axial direction of the outer cylinder fitting 42. The outer surface at the position to be pressed is pressed inward in the radial direction by the surface by each of the metal fitting pressing portions 64-1, 64-2, 64-3 and 64-4, and the diameter is reduced.
That is, in this embodiment, the ellipticity of the elliptical shape of the inner peripheral surface of the die 60 is changed from small to large stepwise from the metal fitting pressing portion 64-3 → 64-2 → 64-1.

FIG. 7 shows a drawing method of the member mount 14 using the drawing die 60.
In the figure, reference numeral 66 denotes a pressurizing portion, which has a tapered surface 68.
Here, when the pressurizing unit 66 is moved downward in the drawing and the drawing die 60 is pressed, the taper surface 68 of the pressurizing unit 66 and the drawing die 60, specifically, the taper surface 70 of the die piece 60h, The die piece 60h is pushed in the centripetal direction, presses the outer cylindrical fitting 42 radially inward from the outer peripheral surface side, and reduces the diameter of the outer cylindrical fitting 42 with plastic deformation.
At the same time, the rubber elastic body 44, specifically, the main rubber portion 50 is pre-compressed in the direction perpendicular to the axis.

  According to the present embodiment as described above, even if the rigidity of the outer cylinder fitting 42 changes along the axial direction, the outer cylinder fitting 42 and the rubber elastic body 44 inside thereof can extend over the entire length in the axial direction. It is possible to satisfactorily suppress the cross-sectional shape from becoming elliptical, and to make the cross-sectional shape close to a perfect circle shape at any position in the axial direction.

Incidentally, Table 1 shows an example of the ellipticity improvement rate of each part in the axial direction of the member mount 14 when the drawing is performed using the drawing die 60 of the present embodiment, and the shape of the inner peripheral surface is a perfect circle having a diameter of φ78 mm. This is shown in comparison with the case of drawing using a drawing die.
Table 2 shows the average ellipticity of the axial positions P _{1 to} P ₄ .

Here, the ellipticity improvement rate is a percentage (percentage) obtained by dividing (ellipticity when using a round die)-(ellipticity when using a drawing die of this embodiment) by the ellipticity when using a round die. ).
The value of the ellipticity of this embodiment in Table 1 is 2.8 (2.8 mm), where the ellipticity of the inner peripheral surface of the aperture die 60 at the axial position P ₁ (reverse elliptical shape) is 2.8 (2.8 mm). the ellipticity at P ₂ 2.3, is the result when the 2.2 ellipticity at _{P 3.}
As is apparent from Tables 1 and 2, by performing the drawing process according to the present embodiment, it is possible to satisfactorily suppress the elliptical shape of the member mount 14 and to bring the shape after the drawing process closer to a perfect circle shape. Can do.

What should be noted is the change in average ellipticity at the axial positions P _{1 to} P ₄ in Table 2. In the drawing process using a perfect circle-shaped drawing die, the average ellipticity is 2.66, whereas in the drawing process using the drawing die 60 of the present embodiment, the average ellipticity is 0.97. The ellipticity is greatly reduced.

Axial position P ₁ in Table 1 is the end to become part of the press-fitting side when press-fitting the member mount 14 relative to the holder 12, ellipticity of this part a large effect on the press-fitting property. Ellipticity of the portion of the axial position P ₁ in the present embodiment has been greatly improved with ovality in the region of the axial position P _2, P _3.

  In the present embodiment, the outer peripheral surface of the outer cylindrical metal fitting 42 is directly pressed by the metal fitting pressing portions 64-1, 64-2, 64-3 at a position between the rubber pressing portions 62-1, 62-2, 62-3. I'm going to do it.

In this case, the inner peripheral surface shape of the metal fitting pressing portions 64-2 and 64-1 is continuous in the axial direction as shown in FIGS. 9 (a) and 9 (b), for example. If the shape is a shape that changes the ellipticity, that is, an inclined surface that is inclined with respect to the axial direction of the outer cylinder fitting 42, the fitting pressing portions 64-2 and 64-1 approach the outer cylinder fitting 42 side. The outer tubular fitting 42 will be pressed by the corner K that has been taken out. That is, the outer cylinder fitting 42 is squeezed only at the corners.
In FIG. 9, (a) represents a longitudinal section obtained by cutting the die 60A in the Y direction, and (b) represents a longitudinal section obtained by cutting in the X direction.

Therefore, in this embodiment, the shape of the inner peripheral surface of the metal fitting pressing parts 64-1 to 64-4 is a straight shape in the axial direction of the outer cylindrical metal fitting 42, and the metal fitting pressing parts 64-3 to 64-1. The ellipticity changes from small to large in a stepwise manner from the axial end on the flange portion 48 side to the opposite axial end.
Thereby, it can avoid effectively that the metal fitting press parts 64-1-64-4 press the outer cylinder metal fitting 42 in the corner | angular part which protruded near the outer cylinder metal fitting 42 side.

Although the embodiment of the present invention has been described in detail above, this is merely an example.
Above Symbol embodiment For example, although without the inner peripheral shape of the drawing die and the circular shape in the axial direction position P _4, which to the it is possible to form an elliptical shape (reverse elliptical shape), GORE It is also possible in some cases to change the shape of the pressing portion to an elliptical shape and to further change the ellipticity stepwise in the axial direction.
Moreover, in the said embodiment, although the flange part 48 in the outer cylinder metal fitting 42 has comprised the annular | circular shape which continued in the circumferential direction, this invention is also applied to what has the flange part of the form parted by the circumferential direction predetermined part depending on the case. Can be applied.
In addition, the present invention can be applied to general production of a flanged cylindrical vibration-proof rubber other than the member mount, and the present invention can be configured in various forms without departing from the gist thereof.

10 Car body side member 13, 48 Flange part 14 Member mount (Tubular anti-vibration rubber)
40 Inner cylinder bracket 42 Outer cylinder bracket 44 Rubber elastic body 56 Straight section 58-1, 58-2, 58-3 Band-shaped rubber section 60 Diaphragm die 62-1 62-2 62-3 Rubber pressing section 64-1 64-2, 64-3, 64-4 Bracket pressing part

Claims (2)

A cylindrical rigid inner cylinder member, a cylindrical outer cylinder bracket having a flange portion projecting radially outward on one end side in the axial direction, surrounding the inner cylinder member at a radially spaced position, and Cylindrical rubber elastic body provided with a straight portion at a position opposed to the direction perpendicular to the axis with the inner cylinder member interposed therebetween, which is integrally vulcanized and bonded in a state of elastically connecting the inner cylinder member and the outer cylinder fitting If, have a, secured to the outer peripheral surface of the outer cylinder metal fitting, to a state of projecting a strip rubber portion extending annularly from the outer circumferential surface at intervals in the axial direction at a plurality of locations around the axis of the outer tubular member The flanged cylindrical anti-vibration rubber
(a) a vulcanization step of vulcanizing and molding the rubber elastic body and integrally vulcanizing and bonding the inner cylinder member and the outer cylinder fitting;
(b) after the vulcanization step, using a drawing die to press the outer cylinder fitting radially inward from the outer peripheral surface side to reduce the diameter;
A method of manufacturing a flanged cylindrical vibration-proof rubber manufactured through
In the drawing process in the drawing process, as the drawing die,
The shape of the inner peripheral surface of a portion of the metal fitting pressing portion that is in direct contact with and presses against the outer cylindrical metal fitting, excluding the portion that presses the end portion on the flange portion side, is in a position opposite to the axis perpendicular direction. An elliptical shape in which the diameter in the X direction connecting the part and the straight part is the major axis and the diameter in the Y direction perpendicular to the axis and perpendicular to the X direction is the minor axis,
And the difference between the major axis and the minor axis is the ellipticity, the ellipticity is a shape that changes from small to large from the axial end on the flange portion side to the axial end on the opposite side ,
In a plurality of axial positions corresponding to the band-shaped rubber portion on the inner peripheral surface of the drawing die, there is a rubber pressing portion that presses the band-shaped rubber portion, forming a concave shape radially outward,
The metal pressing part that directly presses the outer peripheral surface of the outer cylindrical metal fitting at a position between the rubber pressing part and the rubber pressing part at a plurality of positions in the axial direction;
The metal fitting pressing part has a straight shape in the axial direction of the outer cylinder metal fitting, and the ellipticity is small to large for each metal fitting pressing part from the axial end on the flange side to the axial end on the opposite side. A method for producing a flanged cylindrical vibration-proof rubber, wherein the drawing is performed using a drawing die having a shape that changes stepwise . Oite to claim 1, method for producing a flanged cylindrical rubber vibration isolator, wherein the cylindrical vibration isolating rubber is a member mounted for elastically connecting the suspension member and the vehicle body of the vehicle.

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