JP3814165B2 - Drawing method of metal cylinder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for narrowing a metal cylinder.
[0002]
[Prior art]
As shown in FIG. 1, the anti-vibration bush 80 as a so-called metal cylinder includes a substantially cylindrical rubber main body 81, a metal inner cylinder 82, and an outer cylinder 83.
[0003]
In such an anti-vibration bushing 80, it is necessary to compress the rubber main body 81 in order to obtain the desired performance characteristics, and the outer diameter of the outer cylinder 83 is reduced by a predetermined amount during manufacture.
[0004]
In order to reduce the diameter of the outer cylinder 83 and perform the drawing process on the vibration isolating bush 80, a drawing die provided with a drawing hole is used. The throttle hole is formed so that its inner diameter gradually decreases along the axial direction thereof, and the vibration-proof bushing 80 is drawn by pushing the vibration-proof bushing 80 into the throttle hole. .
[0005]
10 and 11 show a press bar 84 for pushing the vibration isolating bush 80 into the aperture hole of the aperture die. The press bar 84 has a structure in which the outer diameter on the front end side contacting the inner wall surface of the throttle hole can be reduced so as to follow the change in the inner diameter of the throttle hole.
[0006]
That is, the portion inserted into the throttle hole is constituted by four substantially arcuate pressing elements 85 which are spaced apart from each other, and the outer diameter of the tip end of the press bar formed by the tips of these pressing elements 85 can be reduced. Each pressing element 85 is supported so as to be swingable by a bolt 86 in a state of being separated from each other. In the figure, 87 is an elastic member made of rubber fixed to the press bar 84 with a bolt 88, and 89 is a shaft member 89 that supports the presser 85 to be rotatable.
[0007]
And the front-end | tip 85a of each presser 85 contact | abuts to the one end surface of the outer cylinder 83 of the anti-vibration bush 80, and the anti-vibration bush 80 is pushed in in an aperture hole.
[0008]
[Problems to be solved by the invention]
However, in such a press bar, as shown in FIG. 10, a gap 90 is generated between the adjacent pressing elements 85 due to the structure. Therefore, as shown in FIG. 9, a protrusion 79 is formed on one end surface of the outer cylinder 83 of the vibration isolating bush 80 with which the pressing element 85 abuts, and the appearance shape of the vibration isolating bush 80 is deteriorated. There is.
[0009]
[Means for Solving the Problems]
Accordingly, the invention according to claim 1 is a drawing die in which a throttle hole in which a metal cylinder is inserted and held is formed, and an insert that pushes the metal cylinder held in the throttle hole along the throttle hole. A pressing rod having a large diameter portion into which the metal cylinder body is inserted and held, and a small diameter hole portion that continues to the large diameter portion via a tapered hole portion, and the insertion hole The body is composed of a plurality of pressing elements having a substantially arc shape in cross section, and has a substantially cylindrical shape as a whole. In the large diameter hole part, the inner wall surfaces of the large diameter hole part are separated from each other. And when the insert is pushed from the large-diameter hole portion toward the small-diameter hole portion, the respective pressing elements correspond to the inner diameters of the tapered hole portion and the small-diameter hole portion, respectively. The tip is brought into contact with the inner wall surface of the tapered hole portion and the small diameter hole portion. The metal cylinder squeezing method using a metal cylinder squeezing device that moves inwardly and has an outer diameter at the distal end of the insert that can be reduced. Rotating means for rotating the drawing die with the center axis of the drawing hole as a rotation center, and pushing the metal cylinder set in the large diameter hole part to the small diameter hole part with a predetermined amount by the press rod, A first step of applying a predetermined amount of drawing to the metal cylinder, a second step of extracting the press rod from the drawing die, and rotating the drawing die by a predetermined amount by the rotating means, and a predetermined amount of rotation. A third step in which the press rod is pushed into the drawing die, the metal cylinder that has been subjected to a predetermined amount of drawing is completely pushed into the small-diameter hole, and drawing is performed to a desired final amount; and Features The press bar is designed so that the maximum outer diameter of the distal end of the insert composed of the respective pressing element tips can be reduced in the range from the inner diameter of the large-diameter hole portion to the inner diameter of the small-diameter hole portion. Thus, a gap is generated between adjacent pressing elements. Accordingly, in the first step, a protrusion is formed on one end surface of the metal cylinder corresponding to the position of the gap between the pressing elements.
[0010]
However, by rotating the aperture die in the second step, the protrusions formed in the first step are crushed and erased by the presser in the third step. Also in the third step, if there is a gap between the adjacent pressing elements, a new protrusion is formed at a position corresponding to this gap. However, since the metal cylinder is drawn in two steps of the first process and the third process, the amount of drawing applied to the metal cylinder in the third process is relatively small. Projections that impair the appearance quality of the cylinder are not formed.
[0011]
According to a second aspect of the present invention, in the first aspect of the invention, the metal cylinder throttle device includes a mechanical hand that supplies the metal cylinder to the aperture die, and a pair of the mechanical hands facing each other. Holding the outer peripheral side of the metal cylinder with the chuck hand and transferring the metal cylinder to above the large-diameter hole, and opening the pair of chuck hands to open the large cylinder Following the metal cylinder setting step of dropping and setting the metal cylinder in the diameter hole and the opening operation of the pair of chuck hands, the pair of chuck hands are closed and attached to the mechanical hand. The metal cylinder insertion confirmation step of confirming whether the pair of chucks are correctly closed by the chuck sensor is performed prior to the first step. If the metal cylinder is not correctly set in the large-diameter hole of the drawing die, the metal cylinder is not completely inserted into the large-diameter hole, and the metal cylinder is caught by a pair of chucks in the metal cylinder insertion confirmation process, The pair of chucks cannot be closed properly.
[0012]
Therefore, by confirming the closing operation of the pair of chucks with the chuck sensor, it is possible to confirm whether the metal cylinder is correctly set in the large-diameter hole in the metal cylinder setting step. Therefore, the metal cylinder protruding in a state inclined from the large-diameter hole portion of the drawing die is not accidentally pressed with the press rod.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[0014]
FIG. 2 is a schematic explanatory diagram of the metal cylinder throttle device 2.
[0015]
The metal cylinder drawing device 2 is a device that uses a metal cylinder such as the vibration-proof bush shown in FIG. 1 described above as a workpiece 3 and performs drawing processing on the workpiece 3, and is hydraulically moved in the vertical direction of FIG. A rod 4 that can move forward and backward, a mounting jig 6 fixed to the rod 4, a metal press bar 8 that is fixed to the rod 4 via the mounting jig 6 and interlocks with the movement of the rod 4, and the workpiece 3 Of a metal drawing die 10 to which a workpiece is set, a drawn workpiece conveying mechanism 12 that is positioned below the drawing die 10 and carries the drawn workpiece 3 to a predetermined position, and a mechanical hand 13 (details will be described later). The workpiece 3 on the conveyor 16 was carried into the drawing die 10 by a pair of chuck hands 14 and 14 (details will be described later) opposed to each other, and was also carried to a predetermined position by the drawn workpiece carrying mechanism 12. Ri the processed workpiece 3 and the workpiece carry-out mechanism 18 for unloading onto the conveyor 16, and is largely constituted by. Reference numeral 19 denotes a work table on which the aperture die 10 is placed.
[0016]
As shown in FIG. 3, an aperture 21 is formed in the aperture die 10. The throttle hole 21 includes a large-diameter hole portion 20 into which the workpiece 3 is inserted and held, a tapered hole portion 22 that is continuous with the large-diameter hole portion 20 and gradually decreases in diameter relative to the inner diameter of the large-diameter hole portion 20; The small-diameter hole portion 24 is continuous with the large-diameter hole portion 20 through the tapered hole portion 22 and has an inner diameter smaller than that of the large-diameter hole portion 20.
[0017]
The workpiece 3 set in the large-diameter hole 20 is pressed toward the small-diameter hole 24 by the press rod 8 and is subjected to a predetermined drawing process in the process of reaching the small-diameter hole 24 through the tapered hole 22. Will be. When the press rod 8 is further pressed, the workpiece 3 falls out of the small-diameter hole portion 24 and is received below the small-diameter hole portion 24 of the drawing die 10. Received). When the receiving pin 26 receives the workpiece 3 that has been drawn, the drawn workpiece transport mechanism 12 is operated, and the receiving pin 26 is moved to the side of the work table 19 and has been drawn by the chuck hands 14 and 14 described above. The workpiece 3 is gripped and carried onto the conveyor 16 described above. The drawn workpiece 3 carried out on the conveyor 16 is conveyed to the next process by the conveyor 16.
[0018]
As shown in FIGS. 4 and 5, the press bar 8 is generally composed of a base body 28 fixed to the mounting jig 6 and a substantially cylindrical insert 30 inserted into the drawing die 10. The insert 30 is longer than the base 28.
[0019]
The base 28 includes a substantially bottomed cylindrical insert receiving portion 32 in which the base end side of the insert 30 is received, a substantially cylindrical base end portion 34 serving as an end on the mounting jig 6 side, and an insert receiving portion. And a substantially cylindrical constricted portion 36 which is located between the portion 32 and the base end portion 34 and connects the two.
[0020]
The outer diameter of the constricted portion 36 is formed to be smaller than the outer diameters of the insert housing portion 32 and the base end portion 34. Further, a protrusion 38 is formed at the center of the base end surface 34 a of the base end portion 34.
[0021]
The insert 30 includes four pressing elements 30a,... 30a that are substantially arc-shaped in cross section and are congruent with each other, and the four pressing elements 30a,. The radius of curvature of the pressing element 30a is equal to or smaller than the radius of the inner diameter of the small hole portion 24.
[0022]
Two bolts 40 inserted from the outer peripheral side of the insert housing part 32 are respectively assembled to the base ends of the pressing elements 30a. The bolt 40 is fixed so as to be orthogonal to the pressing element 30a. A spring 42 is interposed between each bolt 40 and the outer peripheral surface of the insert housing portion 32, and each bolt 40 is radiated in the radial direction of the insert housing portion 32 by the urging force of these springs 42. It is biased toward the outside. Each presser 30a ... a is supported by the base 28 via these bolts 40 in a state of being separated from each other. At this time, the maximum outer diameter of the distal end of the insert 30 constituted by the respective pressing elements 30a... 30a is substantially equal to the inner diameter of the large-diameter hole portion 20 of the drawing die 10.
[0023]
In addition, each through hole 44 provided in the insert housing portion 32 into which each bolt 40 is inserted has a smaller diameter than the head of the bolt 40 but a larger diameter than the shaft portion of the bolt 40.
[0024]
The insert 30 is pushed into the drawing die 10 while the tips of the pressing members 30a... 30a are brought into contact with the inner wall surface of the drawing hole 21. At this time, since the shaft portion of the bolt 40 can be tilted in the through hole 44, the tip of the presser 30 a can move inward corresponding to the inner diameters of the tapered hole portion 22 and the small diameter hole portion 24. Become. That is, the insertion body 30 has a structure capable of reducing the diameter corresponding to the inner diameters of the tapered hole portion 22 and the small diameter hole portion 24. In other words, by allowing the shaft portion of the bolt 40 to swing within the through hole 44, the pressing member 30a is swingable so that the outer diameter of the distal end of the insert 30 can be reduced. It is supported by.
[0025]
As shown in FIGS. 6 and 7, the mounting jig 6 is suspended by a joint member 46 fixed to the tip of the rod 4 and two support bolts 48, 48 on the lower end surface 46 a of the joint member 46. A substantially disc-shaped press bar receiver 50, and a clamp mechanism 52 that is linked to the press bar receiver 50 and the joint member 46 and pushes the press bar receiver 50 toward the joint member 46 are provided.
[0026]
In the center of the lower end surface 46a of the joint member 46, a recess 54 is formed in which the protrusion 38 formed on the base end surface 34a of the base 28 of the press bar 8 is fitted.
[0027]
The press rod receiver 50 is formed with a substantially U-shaped cutout portion 56 into which the constricted portion 36 of the press rod 50 described above can be slid. In addition, a stepped hole 58 is formed in the press bar receiver 50, and by engaging the head of the support bolt 48 described above with the stepped part 58 a of the stepped hole 58, the press bar receiver 50 is It is supported by the joint member 46.
[0028]
In other words, the support bolt 48 only restricts the press rod receiver 50 from dropping from the joint member 46, and the press rod receiver 50 can move toward the joint member 46 along the shaft portion of the support bolt 48. Yes.
[0029]
The clamp mechanism 52 includes a fixed portion 60 fixed to the press bar receiver 50, a pair of arms 64 and 64 that are rotatably attached to the fixed portion 50 via first pins 62 and 62, and one end thereof. A pair of link members 66, 66 that are rotatably attached to the arm 64 via the second pin 65 and whose other end 66 a engages with the lower end of the joint member 46.
[0030]
The other end 66 a of the link member 66 has a relatively large diameter, and is engaged with a step portion 70 a of a stepped hole 70 formed in the flange 68 of the joint member 46. The stepped hole 70 formed in the flange 68 has a substantially oval cross section and is a so-called elongated hole.
[0031]
Further, each link member 66, 66 is in an unclamped state (see FIG. 6), and one end side thereof opens outside the other end 66a, and the stepped hole 70 is a long hole. It is tilted vertically. When the pair of arms 64, 64 are pushed down from this state, the other ends 66a, 66a slide along the corner portions 70b of the step portions 70a, 70a, respectively. That is, the other ends 66a and 66a of the link members 66 and 66 move in the direction perpendicular to the paper surface of FIG. 6 by pushing down the arm.
[0032]
The clamp mechanism 52 is a so-called toggle clamp that uses a link mechanism to perform a large force work with a small force, and lifts the press bar receiver 50 that engages and supports the press bar 8 toward the joint member 46, and presses it. The base end surface 34a of the base body 28 of the bar 8 is brought into contact with the lower end surface 46a of the joint member 46, and the base end part 34 of the base body 28 of the press bar 8 is held between the press bar receiver 50 and the joint member 46 with a large force. It is what you hold.
[0033]
As shown in FIG. 8, the mechanical hand 13 of the work loading / unloading mechanism 18 includes a pair of chuck hands 14 and 14 that face each other, and chuck sensors 72 and 72 that detect the positions of the chuck hands 14 and 14. is doing. Each chuck hand 14, 14 is attached to a main body 74 of the mechanical hand 13 so as to be freely opened and closed. The chuck sensors 72 and 72 are position detection sensors for the chuck hands 14 and 14 that close the pair of chuck hands 14 and 14 and check whether the pair of chuck hands 14 and 14 can be closed to a predetermined position. .
[0034]
Further, as shown in FIG. 8, a rotary cylinder 76 as a rotating means is attached to the aperture die 10. The rotating cylinder 76 can rotate the cylinder die 76 a by a predetermined amount about the center axis of the throttle hole 21 as a rotation center by extending and contracting the cylinder rod 76 a.
[0035]
Next, a work squeezing method using the above-described metal cylinder squeezing device 2 will be described. As the work 3, the vibration isolating bush 80 described above with reference to FIG. 1 is used.
[0036]
First, the outer peripheral side of the anti-vibration bush 80 placed on the conveyor 16 located beside the metal cylinder expansion device 2 is gripped by the pair of chuck hands 14 and 14 of the mechanical hand 13. Then, the mechanical hand 13 is moved and the anti-vibration bush 80 is conveyed to above the large-diameter hole portion 20 of the drawing die 10.
[0037]
Next, the pair of chuck hands 14, 14 holding the vibration isolating bush 80 is opened to drop the vibration isolating bush into the large diameter hole 20 and set in the large diameter hole 20.
[0038]
Subsequently to the opening operation of the pair of chuck hands 14, 14, the pair of chuck hands 14, 14 is closed at the position where the pair of chuck hands 14, 14 is opened, and the vibration isolating bush 80 is large. It is confirmed by the chuck sensors 72 and 72 whether or not it is completely set in the diameter hole portion 20. If the anti-vibration bush 80 is not completely set in the large-diameter hole 20, the anti-vibration bush 80 protrudes from the large-diameter hole 20 (see FIG. 8). Accordingly, when the vibration isolating bush 80 is not completely set in the large-diameter hole portion 20, when the pair of chuck hands 14, 14 are closed, the vibration isolating bush 80 is caught by the pair of chuck hands 14, 14. Thus, the chuck sensors 72 and 72 can confirm that the pair of chuck hands 14 and 14 cannot be closed to a predetermined position.
[0039]
Here, if it is determined by the chuck sensors 72 and 72 that the pair of chuck hands 14 and 14 cannot be closed to a predetermined position, the patrol light is turned on, and the vibration isolating bush 80 is set on the aperture die 10. Inform the worker that an error has occurred.
[0040]
If it is determined by the chuck sensors 72, 72 that the pair of chuck hands 14, 14 can be closed to a predetermined position, the mechanical hand 13 is retracted from the drawing die 10, and the press bar 8 is placed on the drawing die 10. It descends toward the large-diameter hole 20.
[0041]
The drawing process of the vibration isolating bush 80 by the press bar 8 and the drawing die 10 includes first to third processes.
[0042]
In the first step, the press rod 8 is squeezed into the squeeze hole 21 until a squeezing amount 2/3 of the entire squeezing amount is applied to the vibration isolating bush 80 set in the large-diameter hole 20 by the press rod 8. Push into.
[0043]
In the second step, the press bar 8 is once pulled out from the throttle hole 21 and the drawing die 10 is rotated by 45 ° by the rotary cylinder 76.
[0044]
In the third step, the press rod 8 is again pushed into the aperture hole 21 of the aperture die 10 rotated by 45 ° so that the remaining 1/3 of the aperture amount is applied to the anti-vibration bush 80, and the vibration isolator bush contacting the press rod 8 is reached. The press bar 8 is pushed in until one end of the 80 outer cylinder 83 is located in the small diameter hole 24.
[0045]
The pressers 30a... 30a of the press bar 8 have a structure having a gap 78 between the adjacent pressers 30a and 30a. Therefore, when drawing is performed, the extra outer cylinder 83 is left by being squeezed into the gap 78. At the time of the first step described above, as shown in FIG. 9, a protrusion 79 is formed on one end surface of the outer cylinder 83 with which the tip of the pressing element 30a abuts.
[0046]
However, according to the metal cylinder drawing method described above, by rotating the drawing die 10 in the second step, the protrusion 79 formed on one end surface of the outer tube 83 in the first step is pressed in the third step. It will be crushed at the tip of 30a.
[0047]
In addition, since the amount of drawing applied to the vibration isolating bush 80 in the third process is relatively small, the projection 79 that significantly impairs the appearance quality of the vibration isolating bush 80 is formed in the outer cylinder 83 in the third process. It is not formed on one end face.
[0048]
Therefore, the external shape of the vibration-proof bushing 80 that has been subjected to drawing processing can be improved.
[0049]
The mechanical hand 13 is provided with chuck sensors 72 and 72, and each time the vibration isolating bush 80 is set in the large-diameter hole 20, the closing operation of the pair of chuck hands 14 and 14 is confirmed. It is possible to prevent the vibration isolating bush 80 protruding from the large-diameter hole portion 20 from being accidentally pressed with the press rod 8 and prevent the press rod 8 and the diaphragm base 10 from being damaged. At the same time, it is possible to prevent the occurrence of defective products due to defective press.
[0050]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, it can prevent that the protrusion which impairs the external appearance quality of a metal cylinder is formed in the end surface of the metal cylinder which a presser press-contacts.
[0051]
Further, according to the invention of claim 2, the metal cylinder protruding in a state inclined from the large-diameter hole portion of the drawing die is accidentally pressed with the press rod, and the press rod and the diaphragm base are damaged. It is possible to prevent the occurrence of defective products due to defective presses.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an anti-vibration bush as a metal cylinder.
FIG. 2 is an overall configuration diagram of a metal cylinder throttle device.
FIG. 3 is a cross-sectional view of a drawing die of a metal cylinder drawing device.
FIG. 4 is a front view of a press bar.
FIG. 5 is a plan view of a press bar.
FIG. 6 is an explanatory view of a mounting jig of the metal cylinder throttle device.
FIG. 7 is a plan view of a press rod holder of a mounting jig of a metal cylinder throttle device.
FIG. 8 is an explanatory diagram showing a main part of the present invention.
FIG. 9 is a perspective view of an anti-vibration bush that has been drawn by a conventional method.
FIG. 10 is a plan view of a press rod of a conventional metal cylinder throttle device.
11 is a sectional view taken along line AA in FIG.
[Explanation of symbols]
8 ... Press rod 10 ... Drawing die 13 ... Mechanical hand 14 ... Chuck hand 19 ... Workbench 72 ... Chuck sensor 76 ... Rotating cylinder

Claims (2)

An aperture die formed with an aperture hole into which a metal cylinder is inserted and held;
A press rod having an insert for pushing the metal cylinder held in the throttle hole along the throttle hole, and
The throttle hole is composed of a large diameter portion into which the metal cylinder is inserted and held, and a small diameter hole portion continuous with the large diameter portion via the tapered hole portion,
The insert is composed of a plurality of pressers having a substantially arc-shaped cross section and has a substantially cylindrical shape as a whole. In the large-diameter hole portion, the pressers are separated from each other in the large-diameter hole portion. While abutting against the inner wall surface and when the insert is pushed from the large-diameter hole portion toward the small-diameter hole portion, the respective pressing elements correspond to the inner diameters of the tapered hole portion and the small-diameter hole portion, The metal cylinder throttling device is used in which the distal end moves to the inside while contacting the inner wall surface of the tapered hole portion and the small-diameter hole portion, respectively, and the outer diameter of the inserted body distal end can be reduced. A method of squeezing a metal cylinder,
The metal cylinder throttle device includes a rotating means for rotating the aperture die about the central axis of the aperture hole as a rotation center,
A first step in which the metal cylinder set in the large-diameter hole is pushed to a predetermined amount with the press rod toward the small-diameter hole, and a predetermined amount of drawing is applied to the metal cylinder;
A second step of pulling out the press bar from the drawing die and rotating the drawing die by a predetermined amount by the rotating means;
A third step of pressing the press rod into the drawing die rotated by a predetermined amount, completely pushing the metal cylinder subjected to a predetermined amount of drawing into the small-diameter hole portion, and drawing to a desired final amount. And a method of squeezing the metal cylinder. In the metal cylinder narrowing method according to claim 1,
The metal cylinder throttle device includes a mechanical hand that supplies the metal cylinder to the aperture die,
A metal cylinder carrying-in step of gripping the outer peripheral side of the metal cylinder with a pair of chuck hands facing each other of the mechanical hand, and conveying the metal cylinder to above the large-diameter hole,
A metal cylinder setting step of opening the pair of chuck hands and dropping and setting the metal cylinder in the large-diameter hole; and
A metal cylinder that performs a closing operation of the pair of chuck hands following the opening operation of the pair of chuck hands and confirms whether the pair of chucks are correctly closed by a chuck sensor attached to the mechanical hand. An insertion confirmation step is performed prior to the first step, and the metal cylinder squeezing method is characterized in that:

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