JPH0220419B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal cylindrical body drawing device that is suitable for use when drawing the outer cylinder of a rubber bushing with an inner and outer cylinder.

As shown in Fig. 1, a rubber bushing with inner and outer cylinders refers to a rubber bushing whose inner and outer peripheries are covered with metal inner and outer cylinders 2 and 3. The inner and outer cylinders 2 and 3 are integrally joined by so-called vulcanization adhesive, but since the coefficient of thermal expansion of rubber and metal is significantly different, the temperature drop after vulcanization causes the rubber body 1 to Tensile stress is generated between the metal inner and outer cylinders 2 and 3, which adversely affects the life of the rubber bushing 4. For this reason, in the rubber bushing 4, as shown in FIG. 2, a method is adopted in which the outer cylinder 3 is reduced in diameter and the rubber main body 1 is compressed to remove the tensile stress.

The metal cylindrical body drawing device refers to a device for squeezing a metal cylindrical body such as the outer cylinder of a rubber bushing in the above-mentioned cases, and the device generally includes a drawing die 5 as shown in FIG. A plurality of arcuate pressers are arranged in the circumferential direction of the tip end of the press rod so as to form a substantially cylindrical shape, and the large diameter portion 5 of the drawing die 5
When the rubber bush 4, which is the material to be drawn and which is inserted into the hole a, is pressed with a press rod and pushed into the small diameter portion 5b of the drawing die 5, the presser disposed on the circumferential surface of the tip of the press rod resists an elastic member such as rubber. The outer cylinder 3 of the rubber bushing 4 is squeezed by being pressed against the circumferential surface of the press rod and passing through the small diameter portion 5b while reducing its diameter.

By the way, in the conventional metal cylindrical drawing device, as shown in FIGS. 4 and 5, the pressers 7...7 are attached to the circumferential surface of the tip end of the press rod 6 by gluing them to the inner circumferential surface of these pressers 7...7. This is accomplished by using elastic members 8...8 made of rubber or the like and metal screw rings 9 bonded to the inner peripheral surfaces of these elastic members 8...8, resulting in the following drawbacks.

(1) Even if the elastic member 8 ages, it cannot be replaced alone.

(2) When the diameter of the pressers 7...7 is reduced, a large frictional resistance is generated between these pressers 7...7 and the presser guide 6a of the press rod 6 (part A in Fig. 4), resulting in a large capacity. The press rod 6 must be moved up and down using a press machine.

(3) If the pressers 7...7 slip out to the bottom side of the drawing die 5, the press rod 6 should be removed from the drawing die 5.
difficult to extract from.

The present invention has been made for the purpose of solving the above-mentioned conventional drawbacks, and the gist of the present invention is as shown in the drawings from FIG.
7 are rotatably supported by shafts 10...10, and the tips of these pressers 7...7 are supported by elastic members 8.
This is because the diameter of the large diameter portion 5a of the drawing die 5 is expanded to approximately the same diameter as that of the drawing die 5.

In the first embodiment shown in FIGS. 6 to 9, the presser 7
...7 is pivotally supported at its vertical center on the circumferential surface of the press rod 6 by pivots 10...10 so that it has a cylindrical shape with approximately the same diameter as the diameter φB of the small diameter portion 5b of the drawing die 5. At the same time, the tips of these pressers 7...7 are made approximately the same diameter φA of the large diameter portion 5a of the drawing die 5 by an elastic member 8 made of a circular rubber plate attached to the lower surface of the press rod 6 with a bolt 11. It has been expanded in diameter. In addition, 12 and 12' are a pair of bearings provided on the circumferential surface of the tip of the press rod 6 to pivotally support the presser 7, and 13 is a pair of bearings that lock the upper end of the presser 7 to the press rod 6. The locking bolt 13 has a function of holding the pusher 7 in the case where the shaft 10 is broken or the like.

Since the metal cylindrical body drawing device of the first embodiment has the above-described configuration, the rubber bushing is first put into the large diameter portion 5a of the drawing die 5, and then pressed against the outer cylinder 3 of the rubber bushing 4. Child 7…7
When the tips of the pressers 7...7 are brought into contact with each other and pushed into the small diameter section 5b of the drawing die 5 using a press machine (not shown), the tips of the pressers 7...7 will be reduced in diameter from φA to φB according to the inner diameter of the drawing die 5. At the same time, the rubber bush 4 is pressurized, passes through the small diameter portion 5b of the drawing die 5, and the drawing of the outer cylinder 3 of the rubber bush 4 is completed.

10 and the following are other embodiments of the present invention. FIG. 10 shows a case where a coil spring is used as the elastic member 8, FIG. 11 shows a case where a ring spring is used, and FIG. 12 shows a case where a plate spring is used. This shows the case where .

As explained above, the present invention consists of a drawing die 5 and a press rod 6, and a plurality of arc-shaped pressers 7...7 are arranged in the circumferential direction of the tip of the press rod 6 so as to have a substantially cylindrical shape. and the drawing die 5
When the metal cylinder inserted into the large diameter part 5a of the press rod 6 is pressed and pushed into the small diameter part 5b of the drawing die 5, the press elements 7...7 resist the elastic member 8, such as rubber, and press the press rod 6. In the metal cylindrical drawing device, which is pressed against the circumferential surface of the metal cylinder and enters the small diameter portion 5b while reducing its diameter, the pressers 7...7 are connected to the shafts 10...
10 to be rotatably supported on the press rod 6, and the tips of these pressers 7...7 are expanded to approximately the same diameter as the large diameter portion 5a of the drawing die 5 by the elastic member 8. Since it is characterized by being opened, it has the following effects.

(1) When the elastic member 8 ages, only this can be replaced, which is economical.

(2) Since the presser 7 rotates around the shaft 10, almost no frictional resistance is generated between it and the press rod 6 even when it passes through the small diameter portion 5b of the drawing die 5. The squeezing force is small, and the press capacity is also small.

(3) Even if the pressers 7...7 slip out to the lower surface of the drawing die 5, the press rod 6 can be easily pulled out from the drawing die 5.

[Brief explanation of drawings]

Figure 1 is a sectional view of the rubber bushing with inner and outer cylinders, Figure 2
The figure is a cross-sectional view of the outer cylinder of the rubber bushing with inner and outer cylinders reduced in diameter and the rubber body compressed, Figure 3 is a cross-sectional view of a drawing die, Figure 4 is a cross-sectional view of a conventional press rod, and Figure 5 is a cross-sectional view of a conventional press rod. 6 is a front view of the main parts of the press bar of the present invention, FIG. 7 is a plan view of the same, FIG. 8 is a cross-sectional view taken along the line -- of FIG. 7, and FIG. 9 is a view of the main part of the press bar of the present invention. XI-
The XI line sectional view, FIGS. 10, 11, and 12 are sectional views of main parts of other embodiments. 5... Drawing die, 5a... Large diameter part, 5b... Small diameter part, 6... Press rod, 7... Presser, 8... Elastic member,
10... Axis.

Claims (1)

[Claims] 1 Consisting of a drawing die 5 and a press rod 6, a plurality of arc-shaped pressers 7...7 are arranged in the circumferential direction of the tip of the press rod 6 so as to have a substantially cylindrical shape, and the pressing die When the metal cylinder inserted into the large diameter part 5a of the drawing die 5 is pressed with the press rod 6 and pushed into the small diameter part 5b of the drawing die 5, the press elements 7...7 resist the elastic member 8 made of rubber or the like and press the press rod. In the metal cylindrical drawing device, which is pressed against the circumferential surface of the press rod 6 and enters the small diameter portion 5b while reducing its diameter, the press rods 7...7 are connected to the press rods 6 by shafts 10...10.
These pressers 7...
A metal cylindrical body drawing device characterized in that the tip end of the metal cylinder 7 is expanded by the elastic member 8 to approximately the same diameter as the large diameter portion 5a of the drawing die 5.