JP2011206843A - Spinning processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spinning processing apparatus preventing the forming force from being considerably fluctuated by canceling the effect of the centrifugal force which is changed dependent on the position of a forming roller in the radial direction.SOLUTION: The spinning processing apparatus includes: a clamp mechanism 13 for clamping a workpiece W; a rotary drum 25 to be rotated around a rotary shaft 24 along the axis J of the workpiece; a plurality of forming rollers 11 arranged to form pairs at the positional relationship of rotation symmetry; and a forming roller slide mechanism which is fixed to the rotary drum to movably support the forming rollers 11 in the radial direction of the rotary drum 25. The spinning processing apparatus has a structure provided with an urging mechanism 40 for urging the urging force which is changed so as to cancel the centrifugal force of the forming rollers 11 supported by the rotary drum 25 and increased/decreased according to the change in the turning radius including the increase/decrease of the centrifugal force to the forming rollers 11 from the outer circumferential side of the forming rollers 11.

Description

  The present invention relates to a spinning processing apparatus for processing a cylindrical workpiece.

  Iron or stainless steel pressure vessels (bombs) are used for containers filled with various high-pressure gases. In addition, a fuel cell vehicle, which is a next-generation vehicle, requires a lightweight pressure vessel with high pressure resistance for filling and mounting hydrogen fuel. A pressure vessel in which a reinforced resin layer is formed on the outside of a metal liner is used.

  Metal pressure vessels and metal liners are formed with dome parts having curved surfaces (for example, bowl-shaped, semi-circular, elliptical curved surfaces) whose diameter is smaller than that of the body at both ends of the cylindrical body. The bottom part is formed through the dome part, and the base attaching part is formed through the dome part. In general, the part from the dome part to the bottom part and the base attaching part is often formed by a spinning process by pressing a forming roller (see Patent Document 1).

By the way, in the spinning process as illustrated in Patent Document 1, one forming roller is used, the cylindrical member to be processed is rotated, and the processed part (dome portion) of the rotating cylindrical member is rotated. Or a base attachment portion), and is deformed into a desired shape by pressing from one direction.
However, in this processing method, the pressing force applied by the forming roller during the processing acts so as to decenter the cylindrical member from the rotating shaft. As a result, the stability of the workpiece formed by spinning processing deteriorates. Was easy to escape from the chuck.

Further, in the spinning process as illustrated in Patent Document 1, it is common to fix the outer peripheral surface of the cylindrical member so as to be gripped by a chuck mechanism and to rotate the cylindrical member by a rotating mechanism. In that case, when the centrifugal force is applied by rotation, the holding force of the cylindrical member by the chuck mechanism is weakened, the position is shifted during processing, the outer peripheral surface is damaged, and the processing accuracy is defective. It will be.
Therefore, the pressing force of the roller is limited so that the stability of the workpiece does not become a problem, and the rotation speed of the rotating mechanism is limited so that the positional deviation due to the centrifugal force does not become a problem. Spinning processing is performed.

  In addition, as a conventional example of another spinning molding machine, a forming roller that performs spinning by reducing the turning radius while turning along the outer peripheral surface of a cylindrical workpiece, and the outer peripheral surface of the workpiece formed by the forming roller A structure including a cutter that cuts unnecessary portions by swiveling along, a workpiece is fixed by a clamp portion, and a rotating shaft that drives both the forming roller and the cutter to rotate, a forming roller and a cutter Separately, a linear slide that is supported so as to be separated and approachable with respect to the rotating shaft, and driving means for displacing one of the linear slides related to the forming roller or the cutter with respect to the rotating shaft (specifically For example, the draw bar that passes through the inside of the rotating shaft and moves in the axial direction) and the displacement of the one linear slide Those to and a link mechanism for transmitting the other linear slide is disclosed as the displacement (see Patent Document 2).

  According to this, since the linear slide relating to each of the forming roller and the cutter is connected by the link mechanism, the centrifugal force acting on each of the forming roller and the cutter when rotating is acting as a force to cancel each other's centrifugal force. Therefore, problems such as vibrations caused by centrifugal force are solved.

JP 2007-113590 A JP 2004-291048 A

  In contrast to the spinning process described in Patent Document 1, in the spinning molding machine described in Patent Document 2, since the work (tubular member) is fixed at the clamp portion without rotating, the centrifugal force does not work on the work, There is no problem that the work holding force is weakened by the centrifugal force, causing a positional shift or a scratch. Further, since the centrifugal force acting on the forming roller is canceled out by the centrifugal force acting on the cutter, problems due to the centrifugal force acting on the forming roller can be reduced.

However, in the spinning molding machine described in Patent Document 2, the centrifugal force applied to the molding roller varies depending on the position of the molding roller.
That is, the centrifugal force F can be expressed by the following equation (1), assuming that the mass is m, the radius is r, and the angular velocity is ω.

F = mrω ² (1)

For this reason, when the turning radius (r) changes, the centrifugal force applied to each of the forming roller and the cutter rotated at a constant angular velocity also changes.

  As described in Patent Document 2, when the forming roller and the cutter are coupled by a link mechanism, the cutter moves to the outside when the forming roller moves inward in the radial direction. The centrifugal force acting on the forming roller decreases, and the centrifugal force acting on the cutter increases. As a result, the difference in centrifugal force varies depending on the position of the forming roller in the radial direction, and the forming force with which the forming roller presses the workpiece varies under the influence of the change in centrifugal force.

Therefore, even if the radial position of the molding roller fluctuates, the present invention increases the molding force depending on the radial position by canceling the influence of the centrifugal force including the fluctuation. It is an object of the present invention to provide a spinning processing apparatus that does not fluctuate.
Another object of the present invention is to provide a spinning device suitable for reducing the processing time by reducing the influence of the fluctuation of the centrifugal force so that accurate spinning can be realized even under high-speed rotation. To do.

  A spinning processing apparatus of the present invention made to solve the above problems includes a clamping mechanism for fixing a cylindrical workpiece, a rotating drum that rotates around a rotation axis along the axis of the workpiece, and an axis of the workpiece A plurality of forming rollers arranged to be paired in a rotationally symmetric positional relationship with respect to the center, and a forming roller fixed to the rotating drum and supporting the forming roller so as to be movable in the radial direction of the rotating drum A spinning mechanism that performs spinning by pressing the forming roller against the workpiece while changing the turning radius, and is supported by the rotating drum and increases or decreases according to a change in the turning radius The urging force that changes so as to cancel out the centrifugal force of the forming roller, including the increase or decrease of the centrifugal force, is formed from the outer peripheral side of the forming roller. It is so equipped with a biasing mechanism for biasing over La.

Here, the “clamp mechanism” may be any one that can fix the cylindrical workpiece so as not to rotate about the axis. For example, a clamp mechanism that grips the outer periphery of the workpiece is used.
The “rotary drum” is preferably formed of a disc portion that rotates about a rotation axis and a cylindrical side wall, and these are integrally formed.
Specifically, “arranged so as to be paired in a rotationally symmetric positional relationship with respect to the axis” specifically refers to a positional relationship in which the rotational relationship is 180 degrees with respect to the axial line. It is arranged at two positions. In the three-fold symmetrical positional relationship, the three-fold symmetrical positional relationship means that they are arranged at three positions that are positional relationships that are rotated 120 degrees with respect to each other. In addition, the four-fold symmetrical positional relationship means that the four positions are arranged at positional positions that are rotated 90 degrees from each other about the axis. The same arrangement is also applied to a positional relationship of five or more symmetries, but the apparatus becomes complicated. Therefore, in practice, a positional relationship that is two-fold symmetric and three-fold symmetric is most preferable.
The “biasing mechanism” as used in the present invention refers to a biasing mechanism that biases the forming roller with a biasing force that changes so as to cancel out the centrifugal force of the forming roller, including the increase or decrease of the centrifugal force. That is, when the forming roller described in Patent Document 2 moves to the outside and the centrifugal force increases, an urging mechanism that reversely reduces the urging force that acts on the forming roller is not included. This means an urging mechanism in which the urging force also works greatly when the centrifugal force is increased by moving to the outside. Specifically, the elastic force can be applied to the forming roller from the outer peripheral side of the forming roller, and this can be realized by applying an elastic means (spring or the like) in which the elastic force increases as the forming roller moves outward.

According to the present invention, the forming roller is processed by changing the position in the radial direction while turning at a rotationally symmetric position with respect to the workpiece by the rotating drum and the forming roller slide mechanism. The molding force can be applied in a balanced manner, and processing with high roundness can be performed. When the radial position of the forming roller fluctuates during processing, the centrifugal force applied to the forming roller changes according to the radial position.
That is, as described above, when the forming roller moves radially outward while rotating at a constant angular velocity based on (Equation 1), the centrifugal force becomes large, and when moving radially inward, the centrifugal force is Work small.

  Therefore, when the urging mechanism urges the forming roller from the outer peripheral side of the forming roller and the forming roller moves radially outward and the centrifugal force increases, the urging force is increased by the increased amount. Applying an urging force that counteracts the centrifugal force. When the forming roller moves inward in the radial direction and the centrifugal force decreases, the urging force is reduced by the reduced amount to give an urging force that cancels the centrifugal force. To.

  According to the present invention, even if the radial force of the forming roller changes and the centrifugal force acting on the forming roller changes, it is possible to provide a biasing force that cancels the centrifugal force including the change. Spinning can be performed with a stable forming force regardless of the variation in the position in the radial direction. In addition, it is possible to suppress the molding force from being attenuated by the centrifugal force by the biasing force applied from the outer peripheral side.

In the above invention, the urging mechanism generates a repulsive force generated by compressing a gas sealed in a cylinder supported by the rotating drum with a piston, and a piston rod connected to the piston and the forming roller. A gas spring mechanism may be applied to the forming roller as an urging force.
According to this, when the piston roller is pushed outward due to the molding roller moving outward from the center of rotation, the piston compresses the gas sealed in the cylinder according to the amount of the change, and the molding roller The repulsive force from the cylinder works as an urging force. Even when the position of the forming roller fluctuates due to the centrifugal force applied by the rotation of the forming roller, the urging force increases or decreases in conjunction with the increase or decrease of the centrifugal force, and works to cancel out the centrifugal force including the increase or decrease. become. Moreover, it can also adjust to an appropriate urging | biasing force by adjusting the pressure of the gas to seal.

In the above invention, the cylinder of the gas spring mechanism includes a first cylinder and a second cylinder connected by a communication pipe and arranged in parallel. One end side of each of the first cylinder and the second cylinder is a closed end, and the rotating drum. The first cylinder is slidably inserted into the piston, and a piston rod connected to the piston protrudes from the other end of the first cylinder and is fixed to the molding roller. Is inserted between the other end of the second cylinder and the partition wall, and gas is sealed between the piston of the first cylinder and the partition wall of the second cylinder. An incompressible liquid may be sealed in the space communicated by the pipe.
According to this, the space of the cylinder (second cylinder) that encloses the gas can be increased, the urging force against the centrifugal force can be increased, and the stroke that becomes the moving distance in the radial direction of the forming roller is increased. be able to. At this time, the stroke can be adjusted by increasing or decreasing the diameter of the second cylinder.

In the above invention, the forming roller slide mechanism is arranged in the radial direction of the rotating drum, is pivotally supported at the center side and the outer peripheral side of the rotating drum, and the forming roller is along the radial direction of the rotating drum. A ball screw that is movably screwed and is coaxially supported with respect to the rotating shaft of the rotating drum, one end is screwed with the ball screw end by a bevel gear, and a rotational motion is applied to the ball screw to cause the forming roller to move in the radial direction. And a forming roller adjusting shaft to be moved.
According to this, the adjustment of the position of the forming roller in the radial direction can be accurately adjusted using the forming roller adjustment shaft, and the urging force by the gas spring mechanism described above can be given with good reproducibility. Further, since the centrifugal force acting on the forming roller is supported by the entire ball screw portion, the stress can be dispersed, which is advantageous in durability.

In the above invention, the outer peripheral surface of the rotating drum may be supported by an auxiliary roller.
Thereby, a rotating drum can be rotated stably. Moreover, since the influence by the deformation | transformation to the outer side of a rotating drum by adding centrifugal force to a rotating drum can be suppressed, a biasing force can be given still more stably.

In the above invention, the roller surface of the auxiliary roller is formed with a taper surface that widens as the distance from the rotation shaft increases, and the contact surface with the auxiliary roller in the rotation drum is formed with a taper surface that expands as the rotation shaft is approached. May be.
This makes it possible to prevent the rotating drum from moving in the axial direction even when a force that pulls the forming roller in the direction of the workpiece is applied when performing the spinning process while moving the workpiece backward, and the spinning is stably performed. Processing can be performed. Furthermore, even when centrifugal force acts on the rotating drum and the rotating drum escapes in the direction opposite to the rotating shaft, it is possible to prevent the rotating drum from moving in the axial direction and perform stable spinning processing. be able to.

Sectional drawing seen from the front which shows one Example of the spinning processing apparatus which concerns on this invention. The left view of the spinning processing apparatus of FIG. The fragmentary sectional view which expanded a part of spinning processing apparatus of FIG.

  A spinning device according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of an embodiment of a spinning processing apparatus used when manufacturing a metal liner, as viewed from the front. FIG. 2 is a left side view of the spinning processing apparatus of FIG.
The spinning processing device 1 mainly includes a forming roller driving device 12 that holds the forming roller 11 so as to be rotatable and movable in a radial direction, a clamp device 13 that holds a body portion of a cylindrical workpiece W that is an aluminum liner, The clamp device 13 includes an X-axis drive device 14 that moves forward and backward in the direction of the axis J (X direction) of the workpiece W to move the position of the workpiece W relative to the forming roller 11. Note that the X-axis drive device 14 may drive the forming roller drive device 12.

The forming roller driving device 12 will be described. The forming roller driving device 12 is provided with support plates 22, 23 arranged in parallel at a distance on the right side portion of the hollow frame 21, and a rotating shaft 24 by a bearing attached to these support plates 22, 23. Is supported. The rotating shaft 24 is disposed so as to coincide with the axis J. A rotating drum 25 is fixed to the left end of the rotating shaft 24. A motor (not shown) is connected to the right end of the rotating shaft 24 to rotate the rotating drum 25.
The inside of the rotating shaft 24 is hollow, and a forming roller adjusting shaft 26 is inserted coaxially with the rotating shaft 24. The rotating shaft 24 and the forming roller adjusting shaft 26 can rotate independently. A bevel gear 26a is fixed to the end of the forming roller adjusting shaft 26 on the rotating drum side.

The rotary drum 25 includes a disc portion 25a and a cylindrical side wall 25b. A support body 25d having a through hole 25c is fixed in the vicinity of the center of the disc portion 25a. A through hole 25e is formed in the cylindrical side wall 25b. The ball screw 27 is pivotally supported by the through holes 25c and 25e. The ball screws 27 are arranged radially from the rotation axis side (rotation center) along the radial direction.
A bevel gear 27 a is fixed to the end of the ball screw 27 on the rotating shaft 24 side, and is screwed with the bevel gear 26 a of the forming roller adjusting shaft 26.
A housing 11 a that supports the forming roller 11 is screwed onto the ball screw 27. When the forming roller adjusting shaft 26 is rotated, the ball screw 27 is rotated via the bevel gears 26a and 27a, and thus the forming roller 11 can be moved in the radial direction.
Therefore, the forming roller adjusting shaft 26, the bevel gears 26a and 27a, and the ball screw 27 constitute a forming roller slide mechanism that slides the forming roller 11 in the radial direction.

In the rotating drum 25, the first cylinder 31, the second cylinder 32, the communication pipe 33, the piston 34, the piston rod 35, the partition wall 36, the oil 37 (incompressible liquid), and the nitrogen gas 38 are disposed outside the molding roller 11. A gas spring 40 is provided.
The first cylinder 31 and the second cylinder 32 are connected by a communication pipe 33, and the end on the side close to the communication pipe 33 is a closed end, and is fixed side by side on the cylindrical side wall 25b. The other end of the first cylinder 31 faces the housing 11 a of the forming roller 11. The piston rod 35 connected to the piston 34 in the first cylinder 31 protrudes from the other end of the first cylinder 31, and the tip is fixed to the molding roller 11 (housing 11a). Therefore, when the forming roller 11 moves in the radial direction, the piston 34 slides through the piston rod 35.

  The end 32a of the second cylinder 32 on the side far from the communication pipe 33 is a closed end. A space between the partition wall 36 inserted into the second cylinder 32 and the end portion 32a is a gas chamber 32b, and nitrogen gas 38 is sealed at a desired pressure. The gas to be sealed is not limited to nitrogen gas but may be air or the like. By appropriately setting the sealed gas pressure and the cylinder volume (cylinder diameter), the urging force applied to the forming roller 11 and the stroke that is the movable range of the piston rod 35 can be adjusted. Further, the gas pressure in the gas chamber 32b may be controlled so as to obtain an optimum biasing force during the processing.

  A space sandwiched between the piston 34 of the first cylinder 31 and the partition wall 36 of the second cylinder 32 and connected by the communication pipe 33 is filled with oil 37 that is an incompressible liquid. Therefore, when the piston 34 slides, the partition wall 36 slides through the oil 37.

  Four auxiliary rollers 41 are arranged symmetrically about the axis J on the outside of the cylindrical side wall 25b of the rotary drum 25. Each of the auxiliary rollers 41 has a tapered surface so as to come into contact with the cylindrical side wall 25b, and supports the rotating drum 25 and assists the rotational movement. Further, by making the contact surface a tapered surface, the rotating drum 25 is prevented from moving in the direction of the axis J when a pulling force is applied to the rotating drum 25 toward the clamping device 13 side.

Next, the processing operation by the spinning processing apparatus 1 will be described.
The forming roller adjusting shaft 26 adjusts the position of the forming roller in the radial direction, and the rotating shaft 24 is driven to turn the forming roller 11.
The workpiece W to be processed is fixed by the clamp device 13, and is moved forward and backward by the X-axis drive device 14 with respect to the forming roller 11 that is turning. At this time, the position of the forming roller 11 in the radial direction is adjusted at any time by adjusting the forming roller adjusting shaft 26. As a result, the workpiece W is subjected to spinning processing.

If the forming roller 11 is moved in the radial direction during spinning at a constant angular velocity, the centrifugal force applied to the forming roller 11 changes in proportion to the turning radius.
Specifically, when the forming roller 11 is moved radially outward, the centrifugal force increases. At this time, the piston rod 35 fixed to the housing 11a of the forming roller 11 is displaced according to the amount of movement outward in the radial direction, and slides the piston 34 to the outer peripheral side. The displacement of the piston 34 further compresses the nitrogen gas 38 in the gas chamber 32b through the oil 37 and the partition wall 36, and generates a repulsive force corresponding to the amount of movement. The repulsive force is transmitted as a biasing force to the housing 11a of the forming roller 11 through the partition wall 36, the oil 37, the piston 34, and the piston rod 35. That is, when the forming roller 11 moves outward, the centrifugal force increases, but the urging force by the gas spring 40 also increases, so that the equilibrium can be maintained.
When the forming roller 11 is moved inward in the radial direction, the centrifugal force is reduced, but the urging force by the gas spring is also reduced, so that the equilibrium can be maintained.

(Modified embodiment)
The representative embodiments of the present invention have been described above, but the present invention is not necessarily limited to the above embodiments.
For example, in the above-described embodiment, the rotary drum 25 is formed by the disk portion 25a and the cylindrical side wall 25b, which is a preferable shape, but the cylindrical side wall 25b may not be a complete cylindrical shape, and a part thereof is lacking. You may do it. In other words, the cylindrical side wall 25b is used to fix one end of the gas spring 40 for applying an urging force on the outside of the forming roller 11, and to support one end of the ball screw 27 of the forming roller slide mechanism. However, since there is only a side wall portion necessary for these attachments, it does not have to be a complete cylindrical side wall. Therefore, the rotating drum referred to in the present invention includes a case where it does not have a complete cylindrical side wall.

In the above embodiment, the gas spring mechanism 40 is used. However, the gas spring mechanism 40 may be urged by a repulsive force such as an elastic spring instead of the gas repulsive force.
Others The present invention can be appropriately modified and changed within the scope of achieving the object and without departing from the scope of the claims.

  The spinning processing apparatus of the present invention is used for processing metal liners and the like.

W Work 1 Spinning processing device 11 Forming roller 12 Forming roller driving device 13 Clamping device 14 X-axis driving device 24 Rotating shaft 25 Rotating drum 26 Forming roller adjusting shaft 26a Bevel gear 27 Ball screw 27a Bevel gear 31 First cylinder 32 Second cylinder 33 Communication tube 34 piston 35 piston rod 36 partition wall 37 oil (incompressible liquid)
38 Nitrogen gas

Claims (6)

A clamping mechanism for fixing a cylindrical workpiece;
A rotating drum that rotates about a rotation axis along the axis of the workpiece;
A plurality of forming rollers arranged to form a pair in a rotationally symmetric positional relationship about the workpiece axis;
A molding roller slide mechanism fixed to the rotating drum and supporting the molding roller movably in the radial direction of the rotating drum;
A spinning device that performs spinning by pressing the forming roller while changing a turning radius with respect to the workpiece,
The urging force, which is supported by the rotating drum and changes so as to counteract the centrifugal force of the forming roller that increases or decreases according to the change of the turning radius, including the increase or decrease of the centrifugal force, is applied to the forming roller from the outer peripheral side of the forming roller. A spinning processing apparatus comprising a biasing mechanism for biasing.   The biasing mechanism applies a repulsive force generated by compressing a gas sealed in a cylinder supported by the rotating drum with a piston via a piston rod connected to the piston and the forming roller. The spring processing device according to claim 1, wherein the spring processing device is a gas spring mechanism that is applied to the forming roller as a gas spring.   The cylinder of the gas spring mechanism is composed of a first cylinder and a second cylinder connected by a communication pipe and arranged in parallel, and one end side of each of the first cylinder and the second cylinder is a closed end and is fixed to the rotating drum, In the first cylinder, the piston is slidably inserted, and a piston rod connected to the piston protrudes from the other end of the first cylinder and is fixed to the molding roller. The second cylinder has the other end closed. Then, a slidable partition wall is inserted, and gas is sealed between the other end of the second cylinder and the partition wall, and is sandwiched between the piston of the first cylinder and the partition wall of the second cylinder and communicated by a communication pipe. The spring processing apparatus according to claim 2, wherein an incompressible liquid is sealed in the space. The forming roller slide mechanism is arranged in the radial direction of the rotating drum, is pivotally supported at the center side and the outer peripheral side of the rotating drum, and the forming roller is movable along the radial direction of the rotating drum. A ball screw to be screwed;
A forming roller adjusting shaft that is supported coaxially with respect to the rotating shaft of the rotating drum, has one end screwed into the ball screw end with a bevel gear, and moves the forming roller in a radial direction by applying a rotational motion to the ball screw; The spinning processing apparatus according to any one of claims 1 to 3.   The spinning processing apparatus according to claim 4, wherein an outer peripheral surface of the rotating drum is supported by an auxiliary roller.   The taper surface which expands as the roller surface of the said auxiliary | assistant roller goes away from a rotating shaft is formed, and the contact surface with the auxiliary roller in the said rotating drum is formed as a taper surface which spreads as it approaches a rotating shaft. Spinning processing equipment.

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