Patent Application
20060059972
This application is a continuation of PCT Application No. PCT/JP2004/003830, filed Mar. 22, 2004, which is based upon Japanese Patent Application No. 2003-81614, filed Mar. 24, 2003, Japanese Patent Application No. 2003-81633, filed Mar. 24, 2003, and Japanese Patent Application No. 2003-81639, filed Mar. 24, 2003, each of which is hereby incorporated by reference in its entirety.
1. Field of the Invention
The present invention generally relates to a method for bending a work piece that is used to convey a liquid, a gas or a solid, including a powder, or a combination thereof, and a device for bending the pipe. More particularly, the present invention relates to an exhaust pipe connecting together an engine and a muffler of a motorcycle, a snowmobile, a four wheeled buggy, and the like.
2. Description of the Related Art
Conventionally, the curved section of the pipe for conveyance is formed with a stainless steel pipe bent to be a certain configuration. This kind of pipe preferably has a fixed inner diameter so that a fluid can smoothly flow through its inner cavity, or, in the exhaust pipe, a pressure wave is not unnecessarily reflected midway. However, when a pipe is bent, a bent outside unevenly exists inside in such a way that a curvature of the bent outer side is smaller than a curvature of a bent inside. The conventional pipe thus has a drawback that a curved portion thereof can be partially flat at a bent portion to narrow a cross section of its inner passage.
Such a drawback can be cleared to a certain extent if the pipe is bent under a condition that a liquid is enclosed in the inner cavity of the bent portion and the pipe is tightly closed (for example, JP-A-2002-254112 (Pages 1 through 12 and FIGS. 1 through 14)).
However, in this bending device, for bending a plurality of portions of a single work piece, when a setup change is made from one bending process to a next bending process, a three way valve is switched so that water can be returned to a water tank from a high pressure pump, and a water pressure in the work piece is decreased to zero every setup change. Thus, a number of working processes are necessary and the working efficiency is low.
Also, in the bending device, a work piece that has been bent is under a wound condition around a roll mold. Processes for removing the bending-finished work piece from the roll mold to temporarily place it, afterwards, for carrying in another work piece that is going to be bent next to set it to the bending device, and for carry out the work piece that has been temporarily placed are necessary, or processes for carrying in a work piece that is going to be bent next to temporarily place it, for removing the bending-finished work piece from the roll mold to carry it out, and, afterwards, for setting the work piece that is temporarily placed to the bending device are necessary.
Therefore, problems are caused. For example, a long time is necessary to remove the bending-finished work piece that is wound around the roll mold and to set the bending-finished work piece that is going to be bent. Also, the temporarily placing space needs to be ensured and thus the device can be larger.
This invention is made for solving the problems, and an object of a first invention is to provide a method for bending a work piece and a device for bending the work piece both of which can reduce working processes and improve the working efficiency.
Also, an object of second and third inventions is to provide a method for bending a work piece and a device for bending the work piece both of which can save time for removing a bending-finished work piece and for setting another material that is going to be bent to improve the productivity, and can contribute to making the device compact.
Accordingly, in one aspect of the present invention a method for bending a work piece 30 is provided in which a plurality of middle portions of a single work piece 30 are bent when both ends of the work piece are tightly closed by respective caps and an internal cavity of the work piece is filled with a liquid. An internal pressure of the work piece is adjustable through the caps. The internal pressure of the work piece can therefore be adjusted to match the radius of curvature and angle of curvature sought in each bend. Thus, the internal pressure of the work piece 30 can be adjusted in such a manner that one pressure suitable for one bending is changed to another pressure suitable for a next bending. Advantageously, the pressure changes after the one bending ends and before the next bending process starts.
Another aspect of the present invention involves supporting one end of the work piece with a chucking section of a chucking carriage that can move toward or back from a bending machine side while another end of the work piece is mounted on a supporting section of the bending machine side and a position of the work piece that is set is deflected from a bending section of the bending machine. Further, the one end of the work piece is cantilevered by the chucking section that is positioned at a platform and is movable toward and back from the bending machine. In addition, a pressurizing coupler is connected to a cap of the end to make an internal pressure of the work piece changeable. At least one of the bending machine and the chucking section is moveable relative to the platform to move the work piece to a bending position of the bending section from a setting position at which the work piece is set to be cantilevered by the chucking section relative to the bending machine. Another end of the work piece is bent by the bending machine while another end is supported. After bending in a state that the internal pressure of the work piece is adjusted, the cantilevering support by the chucking section is released, the pressurizing coupler is detached, and the chucking section is moved to the setting portion relative to the bending machine.
A further aspect of the present invention involves a method of making multiple bends to a work piece, wherein the work piece is generally tubular in configuration, the work piece comprises a first end and a second end, a first end cap substantially closes the first end and a second end cap substantially closes the second end, with an internal cavity being defined within the work piece between the first end cap and the second end cap. The method comprises introducing a fluid into said internal cavity through one of said first and second end caps, pressurizing the fluid to a first pressure within said internal cavity, conducting a first bending operation, after conducting the first bending operation but before conducting a second bending operation, adjusting the fluid to a second pressure within said internal cavity, said second pressure corresponding to a desired pressure for conducting the second bending operation and after conducting the second bending operation but before conducting a third bending operation, adjusting the fluid to a third pressure within said internal cavity, said third pressure corresponding to a desired pressure for conducting the third bending operation.
An aspect of the present invention also involves a device for bending a work piece, wherein the work piece is generally tubular in configuration, the work piece comprises a first end and a second end, a first end cap substantially closes the first end and a second end cap substantially closes the second end, with an internal cavity being defined within the work piece between the first end cap and the second end cap. The device comprises a bending device and a chucking carriage. The chucking carriage is moveable relative to the bending device. A pressurizing coupler is axially moveable relative to the chucking carriage. The pressurizing coupler is configured to removably connect with the first end cap. The pressurizing coupler comprises a fluid passage that is in communication with the internal cavity of the work piece when the pressurizing coupler is connected with the first end cap. Pressure adjusting means is provided for altering a pressure in the internal cavity of the work piece to a bend specific pressure prior to a second bending operation and subsequent to a first bending operation.
These and other features, aspects and advantages of the present invention will now be described with reference to the drawings of a preferred embodiment, which embodiment is intended to illustrate and not to limit the invention, and in which figures:
FIGS. 2(a) and 2(b) are perspective illustrations of the exhaust pipe of
FIGS. 11(a), 11(b) and 11(c) are cross sectional views that show a work piece being chucked.
With reference initially to
In a preferred configuration, the motorcycle can have a four cycle, single cylinder engine 3 that is mounted on a vehicle body frame 2. The motorcycle 1 also comprises a front wheel 4, a rear wheel 5, steering handle bars 6 and a seat 7. The exhaust pipe 8 can be connected to the engine 3. A rear exhaust pipe, which comprises a muffler 9 that is disposed at its rear end, is connected to a downstream end of the exhaust pipe 8 in one particular configuration.
With reference now to
With reference now to
A predetermined number of work pieces that are going to be bent are placed on the first pallet 23a, while one or more additional work pieces can be placed on the second pallet 23b. In one configuration, the lifter 24 can be a hand lift for carrying the pallets 23a, 23b. In another configuration, the lifter 24 can be a mechanized device. In the preferred configuration, the lifter 24 is inserted into a space below any one of the pallets 23a, 23b to lift it up. After lifting, the lifter 24 can be used to move the pallet to a desired position before lowering the pallet for loading, for example. Thus, the lifter 24 can be used to sequentially move the work pieces to or from the sealing machine 25.
The sealing machine 25 closes both ends of each work piece with end caps 31, 32 and fills an internal cavity of the work piece with a liquid. Preferably, the end caps 31, 32 are mounted to the work piece ends such that the end caps 31, 32 tightly close the ends of the work piece. In a preferred configuration, the end caps 31, 32 are sealed to the ends of the work piece in a fluid tight configuration.
The bending device 26 is used to bend each work piece in such a manner that the middle regions of the work piece are suitably deformed.
The pressurizing device 80 is used to adjust the pressure of fluid contained within each work piece.
The cap-removing machine 28 removes the end caps 31, 32 from a work piece when it has been suitably formed.
The formed product is then inspected on the inspection table 29 to confirm that the formed product meets any desired quality control measurements.
The respective formed products which have been inspected can then be sequentially loaded on the on-operation carriage 22. When a certain number of the formed products are loaded on the on-operation carriage 22, the on-operation carriage 22 can moved out of the illustrated production line. For instance, the formed products can be moved into storage. Because of the movement of the on-operation carriage 22, the next-operation carriage 21 can be moved to the position at which other inspected formed products are loaded. In other words, the next-operation carriage 21 can be considered an empty carriage onto which formed products can be loaded while the on-operation carriage 22 is being unloaded. The inspected formed products, therefore, can be sequentially loaded onto the next-operation carriage 21.
With reference now to
As shown in
The end caps 31, 32 preferably tightly close the internal cavity of the work piece 30. The respective end caps 31, 32 can be coupled with the sealing machine 25 to fill the internal cavity of the work piece 30 with water or any other suitable fluid, liquid or gaseous. Preferably, the fluid is generally not compressible or is only slightly compressible. After filling, couplings (described below) with the end caps 31, 32 can be released and the water then will be substantially maintained within the internal cavity of the work piece 30 at a predetermined pressure.
In some configurations, the work piece 30 is formed into an elongated tubular structure by bending a flat material, such as a plate or sheet of metal, around a bending plane. In such a configuration, the flat material is bent around a central axis of the work piece. The edges of the work piece that are brought together than can be secured together in any suitable manner (e.g., butt welded and the like). To reduce the likelihood that the welding beads will damage the final work piece 30 and to reduce the likelihood that the welding beads will result in an imperfection in the final work piece 30, the angular orientation of an opening and closing valve 72, which will be described below, is controlled relative to the welding beads when the end caps 31, 32 are mounted to the work piece 30. In other words, the end caps are oriented such that during bending, a plane extending through the centerline of the work piece and a center of curvature is offset from the welding bead.
With continued reference to
Each of the illustrated locking members 35a, 35b comprises a plurality of claws 35a1, 35b1 arranged generally circumferentially and a circular coil spring 35a3, 35b3 that is positioned within one or more ring grooves 35a2, 35b2 formed on an outer circumferential surface of each claw 35a1, 35b1. In some configurations, snap rings, o-rings, circlips and the like can be positioned in the grooves 35a2, 35b2. Other configurations also are possible. The springs 35a3, 35b3 or the like help to return the claws 35a1, 35b1 to an original position following expansion, which will be described directly below.
The outer circumferential surface of each claw 35a1, 35b1 can be moved radially outward to be pressed onto an inner circumferential surface of the end portion of the respective work piece 30. In some configurations, the claw 35a1, 35b1 can be defined by a generally cylindrical member with a single slit and a conical center passage such that only one claw is defined rather than a plurality of claws being defined. In the illustrated configuration, four slits define four claws 35a1, 35b1 but other numbers also can be used.
Each claw 35a1, 35b1 is positioned between an end of the respective outer member 33a, 33b and a combination of a nut 36a, 36b and a wedge 35a4, 35b4. Thus, as the surface area in contact between the wedge 35a4, 35b4 and the claw 35a1, 35b1 increases, the claw 35a1, 35b1 expands outward into more firm contact with the work piece 30, thereby sandwiching the work piece 30 between the claw 35a1, 35b1 and the outer member 33a, 33b.
A supporting member 35a21, 35b21 (e.g., a washer-type member) can be positioned over an inner end of a supporting bolt 34a, 34b and secured thereto by a respective bolt 35a5, 35b5. A suitable seal 35a22, 35b22, which can be formed of rubber or another suitable resilient material, can abut the supporting member 35a21, 35b21. The seal 35a22, 35b22 preferably is positioned over an enlarged a step portion 34a1, 34b1 of the inner end of the supporting bolt 34a, 34b. Moreover, the seal 35a22, 35b22 preferably is positioned between the supporting member 35a21, 35b21 and a plate member 35a23, 35b23.
The plate member 35a23, 35b23 preferably abuts the wedge 35a4, 35b4. As described above, the tapered surface 35a41, 35b41 of each wedge 35a4, 35b4 presses a tapered surface 35a11, 35b11 of the respective claw 35a1, 35b1 so that each wedge 35a4, 35b4 expands in the radial direction to tightly contact on the inner circumferential surface of the work piece 30. Thus, the caps 31, 32 can be securely mounted to the work piece 30.
Each supporting bolt 34a, 34b is arranged to be tightened with the respective nut 36a, 36b, which is screwed onto an outer end of the bolt 34a, 34b so that the supporting member 35a21, 35b21 and the plate 35a23, 35b23 can together squeeze the respective seal 35a22, 35b22. That is, by tightening the nut 36a, 36b, each seal 35a22, 35b22 is compressed in its axial direction which advantageously expends it in the radial direction. Thus, an outer circumferential surface of each seal 35a22, 35b22 can be pressed into engagement with the inner surface of the work piece 30. In one advantageous configuration, the seal 35a22, 35b22 forms a substantially or completely water tight seal with the inner surface of work piece 30.
In the illustrated embodiment, each supporting bolt 34a, 34b advantageously has a step section 34a1, 34b1 defined by a larger diameter portion. If the nut 36a, 36b is excessively tightened, the step section 34a1, 34b1 will abut on the plate 35a23, 35b23. Thus, the extent to which each seal 35a22, 35b22 can be compressed in its axial direction is regulated, which reduces the likelihood of the seal 35a22, 35b22 being excessively expanded in the radial direction or compressed in the axial direction.
A supporting member, which is not shown, of the sealing machine 25 preferably engages a flat 33a2, 33b2 that is formed on each of the outer members 33a, 33b. In other words, the generally cylindrical outer members 33a, 33b are preferably provided with a flat 33a2, 33b2 that can be used by the sealing machine 25 to support the outer member 33a, 33b in the axial direction and in the circumferential direction. Thus, the flat 33a2, 33b2 defines an orienting structure. Any other suitable orienting structure also can be used.
In the illustrated end cap 32, a spin-stop key 37b is inserted into the illustrated outer member 33b in the radial direction. The key 37b preferably is positioned within a key slot 34b2 formed in the supporting bolt 34b. The key 37b can reduce the likelihood of the end cap 32 rotating relative to the supporting bolt 34b when the nut 36b is tightened on the outer end of the supporting bolt 34b. Other configurations also can be used.
Also, a coupling member 38b1 can be secured to a chucking section side of the outer member 33b. In the illustrated arrangement, the coupling member 38b1 is secured to the outer member 33b with threaded fasteners 38b2, but any suitable manner of joining the coupling member 38b1 to the outer member 33b1 or to another component of the end cap 32 can be used.
In the illustrated end cap 32, an aperture 34b3 is formed through the supporting bolt 34b. In one configuration, the aperture 34b3 is formed at an axial center of the supporting bolt 34b. In one preferred configuration, the aperture 34b3 is formed by drilling but any suitable technique can be used. The aperture 34b3 communicates with an aperture of the other bolt 35b5. In some configurations, the aperture of the bolt 35b5 is positioned in the center of the bolt 35b5. Thus, an internal cavity of the work piece 30 can communicate with an external location through the end cap 32. In other words, the internal cavity of the work piece is fluidly connected to a passage formed through the end cap 32. A pressure receiving coupler 70 can be attached to the outer end of the supporting bolt 34b such that the pressure receiving coupler is in fluid communication with the internal cavity of the work piece 30.
The pressure receiving coupler 70 can comprise a check valve 70a that is defined by an internal passage in which a ball is positioned. The ball is biased by a spring 70b such that the ball restricts flow to a first direction and the flow in the first direction can only occur if sufficient pressure moves the ball from a seat defined in the internal passage by overcoming the biasing force of the spring 70b. In some arrangements, however, the check valve 70a can be opened by a mechanical interaction. For instance, a pressurizing coupler 52 can be provided with a push rod, which is not shown, that extends into the passage and pushes the ball of the check valve 70a such that flow can occur in both directions when the ball is unseated by the push rod. In other words, when the associated pressurizing coupler 52 is attached, the check valve 70a is opened by the push rod.
In the illustrated embodiment, the coupler 70 can be provided with a quick-disconnect style of coupling. For instance, in the illustrated configuration, a groove 70c extends around the outer circumference of the coupler 70. The groove 70c engages with a suitable structure to maintain a connection between the coupler 70 and the pressurizing coupler 52. Such a structure will be described in greater detail below.
In the illustrated end cap 31, a cross member 34a2 extends through the supporting bolt 34a and provides the bolt with a generally cross shaped configuration. The cross member 34a2 and the bolt 34a can be formed of separate components that are mounted together or the two elements can be integrally formed from a single piece of material. The cross member 34a2 preferably engages with a groove 33a3 having a generally u-shaped cross-sectional configuration formed at a bottom portion 33a1 of the outer member 33a. Thus, the nut 36a that is screwed onto the outer end of a generally vertical portion of the supporting bolt 34a is generally prevented from rotating relative to the supporting bolt 34a when the nut 36a is tightened.
An L-shaped discharge passage 34a3 is formed in the supporting bolt 34a. The L-shaped discharge passage 34a3 communicates with a central aperture of the bolt 35a5, which secures the supporting member 35a21 to the end of the supporting bolt 34a. Thus, a passage extends between the inside and the outside of the work piece 30 through the supporting bolt 34a. In one configuration, the passages are positioned along the axial center of the respective components.
The discharge passage 34a3 communicates with a discharge passage 71a formed in a coupler 71. The coupler can be disposed at a tip of the cross member 34a2 of the supporting bolt 34a. Other configurations also can be used. A washer 31a can be used to close an end of the U-shaped groove 33a3. Thus, the axial end of the illustrated end cap 31 can have a recessed groove 33a3 that is generally enclosed by the washer 31a.
The illustrated coupler 71 comprises an opening and closing valve 72 that can be used to open and close the discharge passage 71a. In the illustrated arrangement, however, the pressure receiving coupler 70 has a check valve 70a such that flow can be generally limited to one direction while the coupler 71 is constructed without a check valve such that flow can freely occur in both directions. When the coupler 71 has the valve 72 in an open position, the inner chamber of the work piece 30 can be maintained at substantially ambient pressure.
Also, in the illustrated configuration, a groove 35a51 is defined in a side surface of the hexagonal head of the bolt 35a5 of the supporting member 35a21. A cross aperture 35a52 communicates with the groove 35a51 and places the inside of the work piece 30 in fluid communication with the central aperture 34a3. Those grooves 35a51, 35a52 define an air ventilation passage 35a53.
When both ends of the work piece 30 are tightly closed by the end caps 31, 32, the work piece can be filled with a suitable fluid, such as water. The fluid can be added through the pressure receiving coupler 70 with the work piece 30 extending generally parallel with the floor. Because air around the hexagonal head of the bolt 35a5 is discharged through the air ventilation passage 35a53, the discharge passage 71a and the coupler 71, almost all of the air in the work piece 30 can be discharged outside. Once almost no air remains in the work piece 30, and the fluid, fills the internal cavity of the work piece 30, a bending process of the work piece 30 can be performed to make suitable bends in the middle region of the work piece 30.
With reference now to
The illustrated bending machine 40 generally comprises a bending section 41, a clamping section 42 and a pressing section 43, which is shown in
In the illustrated configuration, the bending machine 40 comprises a number of hydraulic and air cylinders. A hydraulic cylinder CY4 clamps the work piece 30, which is interposed between the clamping section 42 and the bending section 41. A hydraulic cylinder CY5 rotates the clamping section support table to bend the middle portions of the work piece 30. During the bending process, a hydraulic cylinder CY6 drives the pressing section 43 to press and hold the work piece 30. A hydraulic cylinder CY7 is used to axially move a booster. An air cylinder CY8 is used to axially move a pipe receiving rack arm while another air cylinder CY9 is used to rotate the pipe receiving rack arm.
As shown in
The illustrated chucking carriage 50 comprises a chucking section 51. The chucking section 51 comprises a hydraulic cylinder CY3 that cantilevers the end cap 32 of the work piece 30. The chucking section 51 also comprises the pressurizing coupler 52, which was introduced above. The coupler 52 can be used to adjust or increase the internal pressure of the work piece 30 through the end cap 32. The illustrated chucking section 51 also comprises air cylinders CY1, CY2 that can move the pressurizing coupler 52 and the chucking section 51 together in an X axis direction and a Z axis direction. Preferably, a moving section 53 can also axially move the chucking carriage 50 in a Y direction. Thus, the illustrated chucking carriage 50 advantageously is capable of movement in all three dimensional directions. Other configurations also can be used.
The moving section 53 includes a Y axis (fore to aft) motor M1, a chain 61 driven by the Y axis (i.e., fore and aft) motor M1, and a pair of guide rails 62, 62. The Y axis (i.e., fore and aft) motor M1 rotates the chain 61 in a first or second direction. Thus, the chucking carriage 50 moves axially in the Y axis direction along the guide rails 62, 62. The chain 61 extends between a pair of sprockets 61a, 61b. The Y axis (i.e., fore and aft) motor M1 drives the first sprocket 61a or the second sprocket 61b. In the illustrated configuration, the motor M1 drives the first sprocket 61a. Other configurations, including those with a linear actuator or a gear train, also can be used.
The illustrated chucking carriage 50 has a twisting motor M2 that rotates about a central axis R of the chucking section 51. The twisting motor M2 rotates the work piece 30 so that a bending direction of the work piece 30 can be changed.
The X axis (transverse) air cylinder CY1 and the Z axis (vertical) air cylinder CY2 are connected to the chucking carriage 50. The X axis (transverse) air cylinder CY1 is attached to the chucking carriage 50 to move in a transverse direction a chucking table 50a on which the chucking section 51, the pressurizing coupler 52, the twisting motor M2 and the like are mounted. The Z axis (vertical) air cylinder CY2 moves the chucking table 50a in a vertical direction.
With reference now to
The hydraulic cylinder CY3 also is attached to the chucking carriage 50. As shown in
The illustrated chucking table 50a also comprises a Y axis air cylinder CY10 for the pressurizing coupler, an air cylinder CY11 that can be used to unlock the pressurizing coupler 52, if any, and an air cylinder CY12 that can be used as an air removal device. With reference to
In the illustrated bending device 26, the work piece 30 is moved from a setting position, such as that shown in
As thus discussed, as the chucking carriage 50 moves back after the bent work piece 30 is wound around the bending section 41, the work piece 30 can be removed while the chucking carriage 50 is moving back because the cantilevering support by the chucking section 51 is released. While the chucking carriage 50 is moving back, the chucking table 50a moves to the setting position P1 from the bending position P2. Thus, the work piece 30 that is going to be bent next can be immediately loaded onto the chucking carriage 50, which results in improved productivity. Also, the work piece 30 that is going to be bent next can be loaded to the chucking section 51 of the chucking carriage 50 prior to the removal of the bent work piece 30 from the bending section 41, and a worker can move to a place for the next process while holding the work piece 30. Thus, the bent work piece does not need to be temporarily placed while a new work piece is being loaded onto the bending device.
Also, when the clamping section 42 releases the work piece 30, the bending section 41 and the clamping section 42 are still in the positions where the sections 41, 42 rotated to effect the bending of the work piece 30, the chucking table 50a has been moved in the direction of the X or Z axis to be placed at the setting position P1, and the new work piece 30 has been loaded onto the chucking section 51. Thus, prior to detaching the bent work piece 30 from the bending section 41, the worker can push the start button SW10, and the ON signal of the button SW10 makes the clamping section 42 together with the bending section 41 pivot about 90 degrees counterclockwise to return to the initial positions thereof, and the work piece 30 that is going to be bent next is automatically clamped. Thus, the worker can immediately (before the clamping section 42 returns to the initial position thereof) move to the place for the next process while holding the work piece 30 after the worker pushes the start button SW10. As a result, in comparison with earlier embodiments (i.e., the worker pushes the start button SW10, returns the clamping section 42 to the initial position thereof from the position shown in
Following bending, after the clamp pusher 42d of the clamping section 42 has moved back, the internal pressure of the work piece 30 is decreased and then the cantilevering support by the chucking section 51 is released and the chucking carriage 50 moves back. Next, the pressing section 43 is retracted. The pressing section 43 thus presses and holds the work piece 30 when the chucking carriage 50 moves back in the Y direction. Therefore, the work piece 30 is not likely to be pulled by the chucking section 51 of the chucking carriage 50, which could result in undesired deformation of the final work product.
In the illustrated embodiment, the pressurizing coupler 52 is capable of moving towards or away from the chucking carriage 50. Preferably, the pressurizing coupler 52 moves away from the chucking carriage 50 prior to the retreat of the chucking carriage 50. Thus, the end cap 32 of the work piece 30 and the pressurizing coupler 52 can be detached from each other. The pressurizing coupler 52 can be detached by the retreat of the chucking carriage 50, which, because the detachment of the pressurizing coupler 52 does not need to be done independently, increases productivity.
Further, in order to connect the coupler 52 and the end cap 32, the pressurizing coupler 52 can be moved forward before the chucking carriage 50 moves forward. Thus, the internal cavity of the work piece 30 can be coupled to the pressurizing device 80, which allows the internal pressure of the work piece 30 to be adjusted before or during the forward movement of the chucking carriage 50, and the internal pressure of the work piece 30 can be continuously increased while the chucking carriage 50 moves forward. Thus, the internal pressure of the work piece 30 can continue to be increased or otherwise adjusted while the chucking carriage 50 moves forward. Therefore, at least a portion of the time, if not all of the time, that is necessary for increasing the internal pressure of the work piece 30 can be overlapped with the time that is necessary for the chucking carriage 50 to move forward, which results in further improved productivity.
In the illustrated bending device 26, the chucking section 51 defines a portion of the chucking table 50a. As shown in
With reference now to
The pressure receiving coupler 70 of the end cap 32 is connected to the pressurizing coupler 70. A pair of pressing members 304, 304 is axially movable relative to a pair of guide holes 301b, 301b formed axially on the chucking cylinder 301 and a pair of guide holes 302b, 302b formed axially on the holding cylinder 302. The pressing members 304, 304 are attached to a sliding cylinder 305 fitted onto the chucking cylinder 301.
The pressurizing coupler 52 extends through the Y axis air cylinder CY10. An operational conduit 310, which can be fixed to a piston (not shown), moves the pressurizing coupler 52 in the Y axis direction (i.e., fore and aft). In the illustrated configuration, the pressuring coupler 52 moves back when the work piece 30 is being set and moves forward after the work piece 30 is set.
As shown in
In order to uncouple the pressurizing coupler 52, the air cylinder CY11 is operated. The pressing members 304, 304 are moved rearward in the Y direction by the sliding cylinder 305 to press a ball pressing ring 70d. As shown in
As thus described, the end cap 32 comprises the pressure receiving coupler 70, while the chucking section 51 comprises the pressurizing coupler 52. The combination of these couplers 70, 52 enable the internal pressure of the work piece 30 to be changed while allowing the two couplers to be detachably coupled. As shown in
The pressurizing coupler 52 has a pin 52a that pushes the check valve 70a of the pressure receiving coupler 52 out of the way as the two couplers 52, 70 are brought together. As shown in
The pressurizing coupler 52 is released from the pressure receiving coupler 70 before it is released from the chucking carriage 50 following bending. At this moment, the ball pressing ring 70d of the pressurizing coupler 52 retracts, and the stopper balls 52b move outward in the radial direction. When the chucking carriage 50 moves back under this condition, the pressurizing coupler 52 is released.
Upon fitting the work piece 30 to the chucking carriage 50 using a human hand and pushing the chucking button SW11, the pressurizing coupler 52 is moved by the operational conduit 310 of the Y axis air cylinder CY10 in the Y axis direction (forward) to be coupled with the pressure receiving coupler 70. The chucking claws 301a expand following the operation of the hydraulic pressure cylinder CY3 for chucking to strongly cantilever the work piece 30 from the inside.
With reference to
As shown in
With reference now to
With reference to
In the illustrated embodiment, the cylindrical portion of the end cap 31 is positioned on the supporting portion 320. Thus, even though the thicknesses and outer diameters of various work pieces may differ, the end cap 31 is secured to the supporting portion 320a and there can, therefore, be consistency in the mounting of the work piece because the end cap 31 is consistently sized. Thus, the respective axes of the work piece 30 and the chucking section 51 can be generally aligned with each other when the work piece 30 is mounted on the supporting portion 320a.
With reference again to
The receiving rack arm 320 can move between a setting position shown in
Thus, the supporting portion 320a and the stopper portion 324 are movable in a direction L2 that extends generally normal to an axis L1 of the work piece 30 mounted on the supporting portion 320aand to a direction going away from the bending section 41, by the movement of the receiving rack arm 320. Because the supporting portion 320a and the stopper portion 324 together move away from the bending section 41 during the bending work of the work piece 30, the supporting portion 320a and the stopper portion 324 do not disturb the bending of the work piece 30.
The bending section 41, the clamping section 42 and the pressing section 43 of the bending machine 40 preferably are combined in a suitable manner, such as that shown in
The illustrated clamping section 42 comprises the clamp pusher 42d (see
In the bending process, the chucking carriage 50 moves forward in the Y axis direction in accordance with the deformation of the work piece 30. In this bending process, a groove 41c of the bending section 41 and a groove of the clamping section 42 capture the work piece 30 therebetween (see
With reference to
When the bending is completed, the clamping section support 502 stops at the bending completion position, and the clamp is released. The work piece 30 remains wound around the groove 41c of the bending section 41 although detachable therefrom. The pressing section 43 moves back in the X axis direction, and the support arm 320 pivots to set the supporting portion 320a at the setting position P1 in the X axis direction and the Z axis direction.
After bending is completed, the chucking carriage 50 has moved back to the retreat position in the Y axis direction. Thus, the one end of the work piece 30 is obliquely fitted onto the chucking section 51, and the other end thereof is mounted on the supporting portion 320a. Then, the work piece 30 is moved forward (approximately 1 mm) to abut on the engaging claws 327a, 327b of the stopper portion. Thereby, the work piece 30 can be precisely positioned in the Y axis direction. Next, the work piece 30 is rotated about its central axis to make the opening and closing valve 72 of the cap 31 abut on a rotation stopper bolt 328 indicated in
After the work piece 30 is precisely positioned in the Y axis direction by abutting on the engaging claws 327a, 327b, the support arm 320 pivots toward the waiting position with the ON signal of the start button pushed by the operator. The chucking section 51 of the chucking carriage 50 thus expands to cantilever the work piece 30. Afterwards, the chucking carriage 50 moves by a predetermined amount in the Y axis direction. Additionally, because the chucking carriage 50 moves by the predetermined amount in the Y axis direction, each bending position of the multiple bending portions in the axial direction can be more precisely controlled. Also, because the chucking section 51 pivots by a certain amount while the chucking carriage 50 moves in the Y axis direction, each bending position of the multiple bending portions about the central axis can be more precisely controlled.
The chucking section 51 moves in the X axis direction and further simultaneously moves in the Z axis direction; thereby, the work piece 30 can be positioned on any desired groove 41c of the bending section 41. Alternatively, in some structures of the bending machine 40, the chucking section 51 can move only in the Y axis direction, in the Y axis direction and the X axis direction, or in the Y axis direction and the Z axis direction. Furthermore, the bending section 51 can move in some embodiments (e.g., in the Z axis direction).
If the chucking section 51 can move only in the Y axis direction, the chucking section 51 preferably is sufficiently retracted to a position where it does not interfere with the previously bent work piece 30 so that the work product 30 can be set to the chucking section 51 prior to detachment from the bending section 41. Also, instead of the movement of the chucking section 51 in the X axis direction, it is practicable that the bending section 41 (including the clamping section support and a pivot shaft) can move forward or backward in the X axis direction.
If the chucking section 51 can move in the Y axis direction and can move in the Z axis direction, the roller of the bending section 41 can be multistage. In such a configuration, the respective grooves 41c, 42a of the multistage can differ from each other so that the outer diameter of each work piece can be changed, or the bending radius thereof can be changed, for example but without limitation.
With reference to the drawings, in
With reference again to
The work piece 30, which has both the ends tightly closed by the end caps 31, 32, is filled with water by the sealing machine 25. In the bending process, the internal pressure of the work piece 30 can be adjusted by the pressurizing device 80.
Next, with reference to
The first and second water tanks 101, 102 communicate with each other through a communicating conduit 106. The circulatory pump 103 sends the water in the first water tank 101 to the second water tank 102 through filters 107a, 107b, 107c. The water returned from a work piece 30 following bending is sent to a receiving tank 28a in the cap-removing machine 28. The water in the receiving tank 28a returns to the first water tank 101 via gravity in the illustrated embodiment, but can be pumped or otherwise conveyed if desired.
The first water tank 101 also can be supplied with water from a water introducing conduit 101a of a municipal facility or the like. A downstream end of the municipal water introducing conduit 101a is connected to a main water supply valve 101b that has an electromagnetic valve controlled by the control device 200 or any other suitable valving configuration. In order to detect respective water levels of the first water tank 101 and the second water tank 102, water level sensors 130, 131 are provided. If the water level falls by evaporation of the water, and the water level detected by the water level sensor 130 decreases lower than the predetermined minimum water level, the control device 200 opens the main water supply valve 101b to provide supplemental water. If the water level detected by the water level sensor 130 reaches a predetermined maximum water level, the control device 200 closes the main water supply valve 101b to stop supplementing the water supply.
Also, when the water level detected by the water level sensor 130 decreases lower than the predetermined minimum water level, the control device 200 drives the circulatory pump 103 to send the water in the first water tank 101 to the second water tank 102. When the water level detected by the water level sensor 130 reaches a predetermined maximum water level, the control device 200 stops the circulatory pump 103.
The water supply pump 104 and the high pressure pumps 105a, 105b are arranged to draw the water in the second water tank 102 through respective bubble detecting sensors 108. Each bubble detecting sensor 108 detects bubbles entrained within the water drawn by the supply pump 104 or the high pressure pumps 105, 105b and sends data regarding the bubble content to the control device 200. If any one of the bubble detecting sensors 108 detects the presence of enough bubbles in the water supply, the control device 200 determines that there is a problem with the water supply and the control device 200 stops the water supply pump 104 and the high pressure pumps 105a, 105b.
Preferably, the water supply pump 104 is driven after both of the ends of the work piece 30 are tightly closed by the end caps 31, 32. An outlet port of the, water supply pump 104 is connected to a water supply coupler 150 through a water supply conduit 109, and the pump 104 supplies water to the work piece 30 if the water supply coupler 150 is connected to the pressure receiving coupler 70 of the end cap 32. Thus, the internal cavity of the work piece 30 can be filled with liquid in the sealing machine 25. It should be noted that the use of water is only a preferred configuration and other fluids can be substituted for water. Accordingly, as used herein, water should be broadly construed to mean fluid unless otherwise apparent from its usage.
A water discharge/air removal coupler 151 connected to the coupler 71 of the end cap 31 is connected to a first water drain 112 including a bubble detecting sensor 110 and a flow sensor 111. A downstream end of the first water drain 112 returns the water to the first water tank 101. The bubble detecting sensor 110 determines whether air removal has been completed or not. The sensor 110 can detect bubbles contained in the water that flows through the first water drain 112 and send corresponding data to the control device 200. The flow sensor 111 detects an amount of the water that flows through the first water drain 112 and sends corresponding data to the control device 200. The flow sensor 111 can be used to detect the flow rate, the flow volume or both. If the flow sensor 111 detects a flow of water while the bubble detecting sensor 110 detects no bubbles, the water supply pump 104 is stopped. Also, an opening and closing valve driving device 950 is driven under the control of the control device 200 to close the opening and closing valve 72.
The high pressure pumps 105a, 105b are driven to bend the middle portions of the work piece 30 under the condition that both of the ends of the work piece 30 are tightly closed by the respective caps 31, 32 and the internal cavity of the work piece 30 is filled with the liquid. The respective high pressure pumps 105a, 105b are arranged parallel to each other providing for the maintenance or inspection thereof, and three ways of operation, i.e., operation of either one of them or both of them, are practicable. Thereby, even though either one of the high pressure pump 105a and the high pressure pump 105b is under the maintenance or inspection, bending can be conducted using the other one.
An outlet port of each high pressure pump 105a, 105b is connected to the pressurizing coupler 52 of the bending machine 26 through either one of pressurizing conduits 150a, 150b and a pressurizing conduit 150c. The pressurizing coupler 52 supplies the pressurized water to the work piece 30 through the pressure receiving coupler 70 for bending. A predetermined number of bends can be made before an air removal coupler 160 of the air removal device is coupled with the pressurizing coupler 52 to remove air from the pressurizing conduit 150c. The air removal coupler 160 is connected to a second water drain 161. An end of the second drain 161 opens at a location in the water tank 101. Thereby, the air existing in the pressurizing path from either one of the high pressure pumps 105a, 105b to the pressurizing conduit 150c can be discharged with the water.
Each pressurizing conduit 150a, 150b has a two-way valve 151a, 151b and a check valve 152a, 152b. A portion of the pressurizing conduit 150c between a connecting point P3 of the pressurizing conduits 150a, 150b and the bending device 26 has a stop valve 153, while another portion of the pressurizing conduit 150c between the connecting point P3 and the first water tank 101 has a throttle valve 154 and a two-way valve 151c. The two-way valves 151a, 151c are connected so that the water discharged from the high pressure pump 105a can be changed to either one of the pressurizing coupler 52 and the first water tank 101. The connection is made so that the water discharged from the high pressure pump 105a can be supplied to either one of the pressurizing coupler 52 and the first water tank 101 by the two-way valve 151a and the two-way valve 151c. The connection is also made so that the water discharged from the high pressure pump 105b can be supplied to either one of the pressurizing coupler 52 and the first water tank 101 by the two-way valve 151b and the two-way valve 151c. In one configuration, the two-way valve 151a is switched by a switch valve 151a1, the two-way valve 151b is switched by a switch valve 151b, and the two-way valve 151c is switched by a switch valve 151c1.
That is, first and second states can be selected. In the first state, the two-way valve 151a or the two-way valve 151b is opened and the two-way valve 151c is closed so that the high pressure pump 105a or the high pressure pump 105b and the pressurizing coupler 52 are connected with each other. In the second state, the two-way valve 151c is opened so that the high pressure pump 105a or the high pressure pump 105b, the first water tank 101 and the pressurizing coupler 52 are connected with each other for decreasing the pressure.
A pressure sensor 155 is connected to the pressurizing conduit 150c to detect a water pressure in the pressuring conduit 150c and to send corresponding data to the control device 200. In this embodiment, plunger pumps are used as the high pressure pumps 105a, 105b. An air passage from an air supply source 156 is bifurcated to air supply conduits 157b, 157c downstream of an air supply conduit 157a to supply air to the high pressure pumps 105a, 105b. Each air supply conduit 157b, 157c has a switch valve 158a, 158b. The switch valves 158a, 158b are used to activate one of the respective high pressure pumps 105a, 105b.
A discharge pressure adjusting device 159 changes a pressure of driving air so that a discharge pressure of each high pressure pump 105a, 105b increases or decreases. The discharge pressure adjusting device 159 changes the pressure of the driving air in response to command value sent from the control device 200. The control device 200 determines the command value in such a manner that the water pressure detected by the pressure sensor 155 is consistent with a predetermined target water pressure. That is, each high pressure pump 105a, 105b is feedback-controlled so that the discharge pressure of the high pressure pump 105a, 105b is substantially consistent with the target water pressure.
The target water pressure can correspond to a particular configuration of the exhaust pipe 8. For example, the target water pressure can correspond to a curvature of each bent portion. That is, a bent portion having a larger curvature (a radius of curvature is smaller) is bent under a higher water pressure than is given to a bent portion having a smaller curvature. During the bending process, for example, the control device preferably controls the water pressure to a generally fixed level, or controls it to be higher while a bent angle of the bent portion becomes larger.
In some configurations, a bent angle sensor can be provided to determine the water pressure in connection with the bent angle. For example, a water pressure can increase from the starting of bending within the water pressure increase corresponding to the bent angle. Also, in accordance with the increase of the bent angle made while the bending process proceeds, the water pressure can gradually increase from the water pressure at the initiation of the bending process to the maximum water pressure that is given when the bent angle becomes, for example, 70-80% of the target angle. Afterwards, while the bending process further proceeds, the water pressure can gradually decrease from the maximum water pressure. Thereby, a bent pipe that has less distortion in its cross section can be obtained because the pipe can be bent along its central line.
The bending device 26 in this embodiment has pressure adjusting mechanism K1 that adjusts the internal pressure of the work piece 30 to each bend of the respective middle portions. In the illustrated configuration, the pressure adjusting mechanism K1 comprises the pressure sensor 155, the control device 200 and the discharge pressure adjusting device 159.
The pressure adjusting mechanism K1 adjusts the internal pressure of the work piece 30 in such a manner that one pressure suitable for one bending is changed to another pressure suitable for a next bending after the first bending operation ends and before the next bending operation begins. Because of the pressure adjustment, a water pressure in the work piece preferably is not decreased which improves productivity by maintaining at least a predetermined water pressure in the work piece.
The work piece 30 is clamped by the clamping section 42 and is pushed by the pressing section 43 during the bending process of this work piece, and the internal pressure is previously adjusted before the clamping and the pressing in such a manner that each pressure becomes the pressure that is suitable for the respective bending that is made after the clamping and the pressing or becomes a certain pressure which is lower than the pressure. Because of the previous adjustment of the pressure, the internal pressure of the work piece 30 is sufficiently high before the clamping and the pressing. Thus, the work piece 30 is not likely to be damaged by the clamping and the pressing of the work piece 30. Additionally, when multiple portions are bent, the pressure is preferably adjusted before each subsequent clamping and pressing action.
The clamping of the work piece 30 is released after the final bending process of the work piece 30 ends, and after the work piece is released, the internal pressure can be reduced to zero or substantially zero. Thus, while clamped, the work piece is under pressure, which pressure preferably is not removed until after the work piece is unclamped. Thus, the work piece 30 is less likely damaged by the clamping of the work piece 30. For this reason, as well, the pressing section 43 preferably is retracted before the internal pressure of the work piece 30 becomes zero or the amount adjacent to zero.
When the bending process described above is used for each bend in a work piece featuring multiple bends, releasing the clamping of the work piece after one bend and, before clamping the work piece for the next bend, adjusting the internal pressure during transit of the work piece results in improved productivity. Further, in one configuration, the internal pressure of the work piece is reduced during the transit, which is easier to do than increasing the internal pressure. Thus, the pressure is adjusted to a level that is suitable for the next subsequent bending operation.
A test pressure that is lower than the pressure suitable for each bending of the work piece 30 is given before the first bending of the work piece 30 starts, and unless the internal pressure of the work piece 30 increases to the test pressure within a preset time when the test pressure is applied, the system detects an abnormality and the identification of such an abnormality results in operation of a warning device 170. In one configuration, an indicator 171 indicates specific abnormal conditions and the high pressure pumps 105a, 105b are stopped. Through the use of such an abnormality detection system, the number of inferior goods produced by the system can be reduced.
With reference now to
Under those conditions, the operator attaches a raw work piece 30 (S1), the operator detaches a completed work piece 30 (S2), and the operator pushes the chucking button SW11 (S3). The pressurizing coupler 52 thus moves forward to be coupled with the pressure receiving coupler 70 (S4), and the chuck of the chucking section 51 is tightened (S5).
Next, the operator pushes the start button SW10 to start the bending operation. Under this condition, the high pressure pump 105a, 105b operates in the water pressure section of the pressurizing device 80 to give a preparatory pressure to the work piece 30, i.e., to provide a test water pressure (S7). The test water pressure is monitored for reductions in the pressure. If this pressure falls below a preset pressure, the control device 200 determines that it is abnormal, and makes a warning (S8).
If the test pressure is sufficiently constant, the control device 200 increases the internal pressure to a first bending water pressure (S9). The receiving rack arm 320 is returned to the waiting position (S10), and the clamping table 44 is returned to its initial position at which it is located before the bending (S11). The chucking carriage 50 is moved to the bending position in the Y axis direction (rearward), the chucking section 51 makes the twisting operation (S12), and the chucking table 50a is moved to the bending position P2 from the setting position P1 (S13).
After the pressurization of the step S9 starts and before or after the step S13 completes, the water pressure is checked whether it is within an allowable range of the first bending water pressure. If the water pressure is out of the allowable range, an alarm is activated (S14). If the water pressure is in the allowable range, the clamping section 42 is tightened, and the pressing section 43 is tightened (S15). The first bending starts (S16). When the first bending is completed (S17), the clamping section 42 is loosened, and the pressing section 43 is loosened (S18). The pressure is changed to a second bending water pressure (S19). The chucking table 50a moves to the P1 position in the X axis direction (S20). The chucking carriage 50 is moved forward in the Y axis direction, the chucking table 50a makes the twist, and, simultaneously, the clamping table 44 is returned to its initial position (S21). The chucking table 50a is moved to the P2 position in the X axis direction (S22).
After the water pressure change S19 starts and before or after the step S22 completes, the water pressure is checked whether it is within an allowable range of the second bending water pressure. If the water pressure is out of the allowable range, the alarm is activated (S23). If the water pressure is in the allowable range, the clamping section 42 is tightened, and the pressing section 43 is tightened (S24). The second bending starts (S25). When the second bending is completed (S26), the clamping section 42 is loosened, and the pressing section 43 is loosened (S27). The pressure is changed to a third bending water pressure (S28). The chucking table 50a moves to the P1 position in the X axis direction (S29). The chucking carriage 50 is moved forward in the Y axis direction (S30). The chucking table 50a is lowered in the Z axis direction so as to set the central axis of the chucking section 51 at the level of the clamp receiver 41a positioned below the roll die 41b (S31). The chucking table 50a is twisted, and, simultaneously, the chucking table 50a is moved to the P2 position in the X axis direction (S32).
After the change of the pressure of the step S28 starts and before or after the step S32 completes, the water pressure is checked whether it is within an allowable range of the third bending water pressure. If the water pressure is out of the allowable range, the warning is made (S33). If,the water pressure is in the allowable range, the clamping section 42 is tightened, and the pressing section 43 is tightened (S34). The third bending starts (S35). When the third bending is completed (S36), the clamping section 42 is loosened (S37). The internal water pressure of the bending completed work is released (S38). The water pressure is checked by the pressure sensor 155 whether it is zero (gauge pressure). If it is not zero, the warning is made (S39).
When the water pressure zero is confirmed, the ball pressing ring 70d of the pressurizing coupler 52 is removed (S40). The chucking of the chucking section 51 is loosened (S41). The chucking carriage 50 is moved back in the Y axis direction, and the receiving rack arm 320 is rotated to the setting position from the waiting position (S42). The chucking section 51 is moved to the P1 position in the X axis direction (S43). The chucking section 51 is raised in the Z axis direction so as to set the central axis of the chucking section 51 at the level of the clamp receiver 41a positioned below the roll die 41b, and the ball pressing ring 70d of the pressurizing coupler 52 is returned (S44). The pressing section 43 is loosened, and the pressurizing coupler 52 is moved back relative to the chucking section 51 (Y axis direction) to prepare for the bending of the next work piece 30 (S45).
Additionally, if respective steps in the following groups (1)-(4) are simultaneously conducted, the time for the bending can be shortened: (1) the steps S9 through S13; (2) the steps S19 through S21 or the steps S19, S21 and S22; (3) the steps S29 through S31 or the steps S29 and S30 through S32; and (4) the steps S40 through S45.
Further, the bending machine 40 side is fixed in the respective X, Y and Z axis directions relative to the platform 500, the chucking section 51 side is movable in the respective X, Y and Z axis directions relative to the platform 500 via the chucking carriage 50 and the chucking table 50a. Alternatively, however, the chucking section 51 side can be fixed to the platform 500, and also the bending machine 40 side is movable in the respective X, Y and Z axis directions relative to the platform 500. That is, a bending machine support is interposed between the platform 500 and the bending machine 40, and the bending machine support is movable in the respective X, Y and Z axis directions relative to the platform 500. Also, a pressing section support is fixed to the bending machine support, and the bending section 41 and the clamping section support 502 are rotatable about the Z axis.
Although the present invention has been described in terms of a certain embodiment, other embodiments apparent to those of ordinary skill in the art also are within the scope of this invention. Thus, various changes and modifications may be made without departing from the spirit and scope of the invention. For instance, various components may be repositioned as desired. Moreover, not all of the features, aspects and advantages are necessarily required to practice the present invention. Accordingly, the scope of the present invention is intended to be defined only by the claims that follow.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2003-81614 | Mar 2003 | JP | national |
| 2003-81633 | Mar 2003 | JP | national |
| 2003-81639 | Mar 2003 | JP | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP04/03830 | Mar 2004 | US |
| Child | 11233534 | Sep 2005 | US |
