JP2007268684A - Machining center, fluid pressure generating device, and clamping method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a machining center, a fluid pressure generating device, and a clamping method capable of shortening a flow passage without providing a driving source for an exclusive fluid pressure apparatus, and improving space efficiency without causing a trouble in table movement by the flow passage. <P>SOLUTION: A clamping device 16 for clamping a workpiece W by a clamping member 21 operated by fluid pressure cylinders 22, 23 is provided on a support plate 14 fixed to the table. A fluid pressure generating mechanism 30 for pressurizing working oil supplied to the fluid pressure cylinders 22, 23 is provided on a support plate 14. The fluid pressure generating mechanism 30 is a pump for generating the fluid pressure by the rotation of a driving shaft 32, and the upper end 32a of the driving shaft 32 is roatably constituted of the spindle through a nut runner detachably mounted to the spindle of the machining center. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a machining center, a fluid pressure generating device, and a clamping method, and more particularly to a machining center, a fluid pressure generating device, and a clamping method provided with a fluid pressure device such as a clamping device for clamping a workpiece.

  Some machining centers that perform various types of machining by exchanging a tool for machining a workpiece (material) use a fluid pressure clamping device to clamp the workpiece. In general, the fluid pressure clamping device is mounted on a table movable in the X and Y directions or on a plate fixed on the table. A working fluid is supplied from a fluid pressure pump installed outside the moving range of the table via a pipe.

In addition, in a machine tool capable of supplying coolant to a machining portion of the workpiece and a workpiece contact portion of the tool via a coolant supply passage formed in the spindle and a tool attached to the spindle during machining of the workpiece. A device that uses a coolant as a working fluid of a workpiece clamping device has been proposed (for example, see Patent Document 1). In this apparatus, the clamping device includes at least a clamping fluid pressure cylinder device to which the coolant is supplied, and a clamping member that is operated by the clamping fluid pressure cylinder device to clamp the workpiece. The hydraulic cylinder device for clamping has a return type cylinder partitioned into a clamping pressure chamber and an unclamping pressure chamber by a piston, and the clamping member is provided on a piston rod extending from the piston. The clamp member is set to a clamp position where the workpiece is clamped by supplying the coolant to the clamp pressure chamber, and the clamp member is not clamped by the clamp member by supplying the coolant to the unclamp pressure chamber. The position is set.
JP 2005-59108 A

  By the way, in the structure which supplies a working fluid to a fluid pressure apparatus via piping from the fluid pressure pump installed outside the movement range of a table, there exist the following demerits. Due to the long piping, the response time becomes long, the possibility of leakage increases, the pressure loss and the amount of fluid retained increase, and the cost increases. Since a pump-only drive source is required, a large number of drive sources are required for the machining center, which complicates control and increases costs. Even when the pump is held in the clamp position as in the clamp device, the power consumption is increased because the pump is always kept in the drive state. It is necessary to arrange the pipe that applies the fluid pressure so as not to hinder the movement of the movable part (table), and the installation position of the pipe and the movement of the movable part (table) are limited, so that the degree of freedom in design is reduced. Further, it is necessary to secure a space for installing the pump outside the moving range of the movable part (table), and the space necessary for installing the machining center becomes large.

  In the device described in Patent Document 1, pressurized coolant is configured to be supplied to the clamp device via the main shaft, and it is not always necessary to move the pump while the clamp device is in the clamped state. However, a pump that pressurizes the coolant to a pressure higher than that used in the hydraulic cylinder device for clamping is required. Moreover, it is necessary to perform special processing on the main shaft.

  The present invention has been made in view of such circumstances, and it is not necessary to provide a drive source dedicated to fluid pressure equipment, and the flow path can be shortened even when the flow path can be shortened and the table moves. It is an object of the present invention to provide a machining center, a fluid pressure generating device, and a clamping method that can prevent movement of the table.

  In order to achieve the above object, the invention according to claim 1 is configured such that a table on which a workpiece is supported and a spindle for performing work on the workpiece supported on the table are configured to be relatively movable. In the machining center in which a fluid pressure device driven by the working fluid is provided on the table, a fluid pressure generating mechanism for pressurizing the working fluid supplied to the fluid pressure device is provided on the table, and the fluid The pressure generating mechanism is driven by utilizing at least one of the operation of the main shaft and the movement of the table.

  Here, “supported on the table” is not limited to the case of being directly supported on the table, but indirectly on the table by being supported on a support portion (for example, a support plate) fixed to the table. Including cases supported by

  According to a second aspect of the present invention, in the first aspect of the present invention, the fluid pressure generating mechanism is a pump that generates a fluid pressure by rotation of a drive shaft, and the drive shaft has an end portion at the main shaft. It is configured to be rotatable together with the main shaft by being connected to the main shaft via a rotation tool that is detachably mounted.

  A third aspect of the present invention is the pump according to the first aspect, wherein the fluid pressure generating mechanism is a pump that generates fluid pressure by reciprocating movement of a drive shaft, and the end portion of the drive shaft is the main shaft. To the main shaft, a tool that is stopped from rotating while being attached to the main shaft, a main shaft support portion that supports the main shaft and reciprocates integrally with the main shaft, or the main shaft support portion. By being pressed by the attached pressing member, it is configured to be able to reciprocate in the axial direction of the main shaft.

  According to a fourth aspect of the present invention, in the first aspect of the present invention, the table is provided so as to be relatively movable with respect to a machining center main body supporting the table, and the fluid pressure generating mechanism is reciprocated by a drive shaft. The pump generates a fluid pressure, and the drive shaft reciprocates in the reciprocating direction of the table by contacting an abutting portion provided on the machining center main body side when the table reciprocates. It is configured to be possible.

  According to a fifth aspect of the invention, in the invention according to any one of the first to fourth aspects, the fluid pressure device operates a clamp member that holds the workpiece between a clamp position and an unclamp position. It is characterized by being a fluid pressure cylinder.

  According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the fluid pressure cylinder is a single-acting cylinder with a spring, and a discharge port of a pump and a port of the fluid pressure cylinder constituting the fluid pressure generating mechanism. A check valve for preventing the backflow of the working fluid to the pump side is provided in the middle of the flow path connecting the flow path to the fluid pressure cylinder from the check valve of the flow path. A branch passage that communicates with the tank connected is provided, and a release valve that can be switched between an open state that communicates the branch passage with the tank and a shut-off state that blocks communication is provided in the middle of the branch passage, The release valve is always held in a shut-off state and is configured to be switchable to an open state by using movement of the main shaft in the axial direction.

  The invention according to claim 7 is a fluid pressure generating device that is provided on a table of a machining center on which a workpiece is supported, and pressurizes a working fluid supplied to a fluid pressure device driven by the working fluid. The pressure generating device includes a fluid pressure generating mechanism provided on the table, the fluid pressure generating mechanism has a drive shaft, and the drive shaft generates fluid pressure by rotating or reciprocating in the axial direction. It is configured, and is configured to be capable of rotating or reciprocating in the axial direction by a force applied from the outside of the fluid pressure generating device.

  The invention according to claim 8 is the pump according to claim 7, wherein the fluid pressure generating mechanism is a pump that generates fluid pressure by rotation of a drive shaft, and the end of the drive shaft is a main shaft in a machining center. It is configured to be able to rotate together with the main shaft by being connected to the main shaft via a rotation tool that is detachably attached to the main shaft.

  The invention according to claim 9 is the pump according to claim 7, wherein the fluid pressure generating mechanism is a pump for generating fluid pressure by reciprocating movement of the drive shaft, and the end of the drive shaft is the main shaft. To the main shaft, a tool that is stopped from rotating while being attached to the main shaft, a main shaft support portion that supports the main shaft and reciprocates integrally with the main shaft, or the main shaft support portion. By being pressed by the attached pressing member, it is configured to be able to reciprocate in the axial direction of the main shaft.

  A tenth aspect of the present invention is the pump according to the seventh aspect, wherein the fluid pressure generating mechanism is a pump that generates fluid pressure by reciprocating movement of a drive shaft, and the end of the drive shaft is the table. The table is configured to be capable of reciprocating in the reciprocating direction of the table by abutting against an abutting portion provided on the side of the machining center main body that supports the table during the reciprocating movement of the table.

  According to an eleventh aspect of the present invention, a table on which a workpiece is supported, a clamp device that fixes and supports the workpiece with a clamp member that is driven by a working fluid, and a tool that is detachably attached to the workpiece are attached to the workpiece. A clamping method for clamping a workpiece in a machining center configured to be movable relative to the table, wherein the clamping device is in contact with and clamps the workpiece. And a fluid pressure cylinder that causes the pressing portion to perform a clamping operation and a clamping release operation, and a fluid pressure generating mechanism that supplies a working fluid to the fluid pressure cylinder is configured to operate the main shaft and move the table. A pump that generates fluid pressure by driving a drive shaft that is driven using at least one of the pump, and the pump In the middle of the flow path connecting the discharge port and the port of the fluid pressure cylinder, a check valve for preventing the back flow of the working fluid to the pump side and a release valve operable by the main shaft are provided, The clamping operation of clamping the workpiece by the clamping device includes a fluid pressure generating step of generating a fluid pressure by driving the pump using at least one of the operation of the main shaft and the movement of the table, A clamping step of supplying the fluid pressure cylinder to abut the pressing portion against the workpiece, and releasing the clamp of the workpiece clamped by the clamping device by operating the release valve by the main shaft And a pressure release step of releasing the pressure of the working fluid supplied to the fluid pressure cylinder. That.

  A twelfth aspect of the present invention is the pump according to the eleventh aspect, wherein the fluid pressure generating mechanism is a pump that generates a fluid pressure by rotation of a drive shaft. In the fluid pressure generating step, the drive shaft The drive shaft is rotated together with the main shaft by connecting the end of the main shaft to the main shaft via a rotation tool that is detachably attached to the main shaft.

  A thirteenth aspect of the present invention is the pump according to the eleventh aspect, wherein the fluid pressure generating mechanism is a pump that generates a fluid pressure by a reciprocating movement of a drive shaft. In the fluid pressure generating step, the driving is performed. When the shaft end is reciprocated in the axial direction of the main shaft, the main shaft, a tool that has been rotated and stopped while mounted on the main shaft, and a main shaft support portion that supports the main shaft and reciprocates integrally with the main shaft. Alternatively, the drive shaft is reciprocated in the axial direction of the main shaft by being pressed by a pressing member attached to the main shaft support portion.

  According to a fourteenth aspect of the invention, in the invention according to the eleventh aspect, the table is provided so as to be movable relative to the machining center body, and the fluid pressure generating mechanism generates a fluid pressure by reciprocating movement of a drive shaft. In the fluid pressure generating step, an end of the drive shaft is brought into contact with a contact portion provided on a machining center main body side that supports the table when the table is reciprocated. Is reciprocated in the reciprocating direction of the table.

  According to the present invention, it is not necessary to provide a drive source dedicated to the fluid pressure device, the flow path can be shortened, and even when the table moves, the flow path can be prevented from hindering the movement of the table. .

(First embodiment)
A first embodiment in which the present invention is embodied in a vertical machining center will be described below with reference to FIGS.

  As shown in FIG. 2, the machining center 11 includes a machining center main body 12, a table 13, a support plate 14 fixed on the table 13, a clamp device 15 that supports and fixes the workpiece W on the support plate 14, and a spindle 16. And a tool storage means 18 for storing the tool holder 17, an auto tool changer ATC, and an operation panel 19. A tool holder 17 is detachably attached to the spindle 16, and the spindle 16 transmits rotation to a tool (tool) 20 detachably held by the tool holder 17 and performs work by the function of the tool 20. .

  The table 13 is mounted so as to be movable in the X direction and the Y direction perpendicular to each other in a horizontal plane with respect to the machining center main body 12 that supports the table 13. For the configuration (not shown) for moving the table 13, for example, a known configuration using a ball screw mechanism or a linear actuator is used. The main shaft 16 extends in a direction perpendicular to the table 13 and is movable in the extending direction by a drive mechanism (not shown). In this embodiment, since the table 13 is disposed horizontally, the main shaft 16 extends in the vertical direction. That is, the main shaft 16 on which the tool 20 is mounted and the table 13 on which the workpiece W (shown in FIG. 1) is supported can be moved relative to each other in a direction perpendicular to the table 13 and in a plane perpendicular to the vertical direction. It is configured.

  Each of the tool holders 17 to which the tools 20 are mounted is stored in the tool storage unit 18 when not in use, and is removed from the tool storage unit 18 by the auto tool changer ATC and mounted on the spindle 16 when in use. . Further, the tool holder 17 on which the tool 20 is mounted is removed from the main shaft 16 by the auto tool changer ATC and stored in the tool storage means 18 when the machining is completed. As these auto tool changer ATC and tool storage means 18, conventionally known ones can be used and they are not characteristic features of the present invention, and therefore their detailed description will be omitted.

  As shown in FIG. 1, the clamp device 15 includes a clamp member 21 as a pressing portion that holds the workpiece W, and fluid pressure cylinders 22 and 23 as fluid pressure devices driven by a working fluid. The fluid pressure cylinders 22 and 23 operate the clamp member 21 to a clamp position and an unclamp position (clamp release position). In this embodiment, hydraulic cylinders are used as the fluid pressure cylinders 22 and 23.

  The fluid pressure cylinders 22 and 23 project from the pistons 22b and 23b and the pistons 22b and 23b that slide in the cylinders 22a and 23a, slidably penetrate the cylinders 22a and 23a, and are outside the cylinders 22a and 23a. Protruding piston rods 22c and 23c are provided. The fluid pressure cylinders 22 and 23 are arranged such that the piston rods 22 c and 23 c extend in the vertical direction in a state where the base end side is accommodated in the accommodation recess 14 a provided in the support plate 14. The fluid pressure cylinders 22 and 23 are single acting cylinders with springs, and the piston rods 22c and 23c are urged toward the immersive side in the chambers on the piston rods 22c and 23c side of the cylinders 22a and 23a across the pistons 22b and 23b. A coil spring 24 is accommodated.

  An intermediate portion of each clamp member 21 is rotatably connected via a support shaft 26 to the other end of a lever 25 whose one end is rotatably connected to the upper part of the cylinders 22a and 23a. Is connected to the tip ends of the piston rods 22c, 23c via a pin 27 so as to be rotatable. An adjustment bolt 28 is screwed to the tip of the clamp member 21 so as to penetrate the clamp member 21, and a nut 29 is screwed to the upper end side of the adjustment bolt 28.

  On the support plate 14, a pump unit 31 is provided as a fluid pressure generating device including a fluid pressure generating mechanism 30 for pressurizing the working fluid supplied to the fluid pressure cylinders 22 and 23 of the clamp device 15. . The pump unit 31 is fixed to the support plate 14 via a bolt 31b penetrating a flange portion 31a projecting from the lower end. The fluid pressure generating mechanism 30 is constituted by a pump that generates fluid pressure by the rotation of the drive shaft 32, and a turbo pump is used in this embodiment. The drive shaft 32 is disposed so as to extend in the vertical direction, and an upper end portion 32a as an end portion of the drive shaft 32 is connected to the main shaft 16 via a nut runner 33 as a rotation tool that is detachably attached to the main shaft 16. The main shaft 16 is configured to be rotatable. Specifically, the upper end 32a is formed in the same shape as the head of the hexagon bolt. As shown in FIG. 3, the nut runner 33 is attached to the main shaft 16 while being held by the tool holder 17.

  The pump unit 31 includes a tank 34 that stores hydraulic oil as a working fluid. The tank 34 communicates with the outside via a passage 34a. The opening of the passage 34a is covered with a lid 35 that allows passage of gas and prevents passage of liquid. That is, the tank 34 is in communication with the atmosphere.

  The suction port 30 a of the fluid pressure generating mechanism 30 and the tank 34 are communicated with each other via a communication path 36. The discharge port 30b of the fluid pressure generating mechanism 30 and the ports 22d and 23d of the fluid pressure cylinders 22 and 23 are connected (communicated) by a flow path 37, and the fluid pressure generating mechanism 30 side of the working fluid is in the middle of the flow path 37. A check valve 38 for preventing backflow to the (pump side) is provided. A branch path 37 a that connects the flow path 37 to the tank 34 is provided closer to the fluid pressure cylinders 22 and 23 than the check valve 38 of the flow path 37. In the middle of the branch path 37a, a release valve 39 is provided that can be switched between an open state in which the branch path 37a communicates with the tank 34 and a blocked state in which the communication is blocked. The release valve 39 is provided with a spool 40, and the spool 40 is arranged so as to be movable in the vertical direction while intersecting the branch passage 37a and not intersecting the communication passage 36.

  The spool 40 has a small-diameter portion 40a that allows the branch passage 37a to communicate with the tank 34, and a portion other than the small-diameter portion 40a is always held at a position corresponding to the branch passage 37a and is disposed below the spool 40. When moved downward against the biasing means 41, the small diameter portion 40a is arranged at a position corresponding to the branch path 37a. A compression spring is used for the biasing means 41. An operated portion 40 b that protrudes outside the pump unit 31 is provided at the upper end of the spool 40, and the operated portion 40 b is provided at a position that can be pressed downward by the main shaft 16. That is, the release valve 39 is configured to be able to be engaged with the main shaft 16 and switched to an open state using the movement (downward movement) of the main shaft 16 in the axial direction.

  1 to 3 are schematic diagrams for explaining the configuration of the apparatus. For easy understanding, the size ratio of the workpiece W, the clamp device 15, the pump unit 31, and the like is different from the actual one. The ratio is different between the drawings.

  Next, the operation of the machining center 11 and the pump unit 31 configured as described above will be described. The operator first sets the workpiece W at a predetermined position on the support plate 14. Next, the operation panel 19 is operated to attach the nut runner 33 to the main shaft 16. The nut runner 33 is stored in the tool storage unit 18 while being held by the tool holder 17, and is mounted on the spindle 16 together with the tool holder 17 by the auto tool changer ATC.

  Next, the operator operates the operation panel 19 to input a command for driving the fluid pressure generating mechanism 30 of the pump unit 31 to the main shaft 16. When the command is input, the table 13 is moved so that the upper end portion 32 a of the drive shaft 32 is positioned on the extension line of the main shaft 16. Next, the main shaft 16 is lowered to a position where the nut runner 33 is fitted to the upper end portion 32a. In this state, the main shaft 16 is rotated, and the drive shaft 32 is rotated together with the main shaft 16. The fluid pressure generating mechanism 30 is driven by the rotation of the drive shaft 32, and hydraulic oil is sucked from the suction port 30a and pressurized and discharged from the discharge port 30b. This step is a fluid pressure generation step for generating fluid pressure. In this state, since the release valve 39 is disposed at a position where the communication state between the branch passage 37 a and the tank 34 is blocked, the hydraulic oil discharged from the discharge port 30 b passes through the flow path 37 to the fluid pressure cylinder 22, 23. Then, the pistons 22b and 23b are moved up against the urging force of the coil spring 24 together with the piston rods 22c and 23c, and the clamp member 21 is actuated to a clamping position where the workpiece W comes into contact with and clamps (holds) the workpiece W. The This process is a clamping process.

  When the drive shaft 32 is rotated for a preset time or number of rotations, the rotation of the main shaft 16 is stopped and the rotation of the drive shaft 32 is also stopped. Then, the main shaft 16 is raised, and the fitting state between the nut runner 33 and the upper end portion 32a of the drive shaft 32 is released. When the rotation of the drive shaft 32 is stopped, no pressure is generated from the fluid pressure generating mechanism 30, but the check valve 38 is provided in the flow path 37, and the release valve 39 is held in the blocking position. Therefore, the hydraulic oil in the flow path 37 and the fluid pressure cylinders 22 and 23 is held in a pressurized state, and the clamp member 21 is held at the clamp position.

  Next, the operator operates the operation panel 19 to store the nut runner 33 in the tool storage means 18. Next, the operator operates the operation panel 19 to attach the tool 20 for performing a desired machining operation to the workpiece W to the spindle 16 and input a command for performing the machining operation. As a result, after the nut runner 33 is stored in the tool storage means 18, a machining operation for the workpiece W is performed by the spindle 16 on which the tool 20 is mounted.

  When releasing the clamping state of the workpiece W by the clamping device 15, the operation panel 19 is operated to remove the tool 20 from the spindle 16 together with the tool holder 17. Next, the operation panel 19 is operated to move the table 13 to a position where the release valve 39 of the pump unit 31 can face the end of the main shaft 16, and then the main shaft 16 is lowered. Then, the operated portion 40b of the spool 40 is pressed by the end portion of the main shaft 16, and the spool 40 is moved down to a position where the small diameter portion 40a corresponds to the branch path 37a. That is, the release valve 39 is operated by the main shaft 16. As a result, the flow path 37 is in communication with the tank 34, the pressure of the hydraulic oil becomes equal to the atmospheric pressure, and the piston rods 22c and 23c are moved downward by the urging force of the coil spring 24 together with the pistons 22b and 23b. This process is a pressure release process. Then, the clamping member 21 is rotated in a direction away from the workpiece W, and the clamping state of the workpiece W by the clamping device 15 is released.

According to this embodiment, the following effects can be obtained.
(1) The table 13 on which the workpiece W is supported and the main shaft 16 that performs the work on the workpiece W supported on the table 13 are perpendicular to the table 13 and in a plane perpendicular to the vertical direction. A fluid pressure device (fluid pressure cylinders 22, 23) configured to be relatively movable and driven by a working fluid is provided on the table 13. A fluid pressure generating mechanism 30 for pressurizing the working fluid supplied to the fluid pressure device is provided on the table 13, and the fluid pressure generating mechanism 30 is driven using the operation of the main shaft 16. Therefore, it is not necessary to provide a drive source dedicated to the fluid pressure device, the flow path 37 can be shortened, and the flow path 37 can be prevented from hindering the movement of the table 13.

  (2) The fluid pressure devices are fluid pressure cylinders 22 and 23 that operate the clamp member 21 that holds the workpiece W to the clamp position and the non-clamp position. Therefore, when the clamp member 21 is operated using the fluid pressure cylinders 22 and 23 as the clamp device 15, it can be suitably handled.

  (3) The fluid pressure generating mechanism 30 is a pump that generates fluid pressure by the rotation of the drive shaft 32. The upper end portion 32a of the drive shaft 32 rotates with the main shaft 16 via a nut runner 33 that is detachably attached to the main shaft 16. It is configured to be possible. Therefore, the fluid pressure generating mechanism 30 can be efficiently driven by the rotation of the main shaft 16.

  (4) The fluid pressure cylinders 22 and 23 are single acting cylinders with springs, and are located in the middle of a flow path 37 connecting the discharge port 30b of the fluid pressure generating mechanism 30 and the ports 22d and 23d of the fluid pressure cylinders 22 and 23. A check valve 38 is provided to prevent the backflow of the working fluid to the pump side. A branch path 37a is provided near the fluid pressure cylinders 22 and 23 from the check valve 38 of the flow path 37 so that the flow path 37 communicates with a tank 34 communicated with the atmosphere. A release valve 39 that can be switched between an open state in which the branch passage 37a communicates with the tank 34 and a shut-off state in which the communication is cut off is provided in the middle of the branch passage 37a. The release valve 39 is always kept in the shut-off state. The main shaft 16 can be switched to the open state by using the movement of the main shaft 16 in the axial direction. Therefore, the clamp member 21 can be moved from the clamp position to the non-clamp position by using the movement of the main shaft 16, and the control is simplified.

(5) Since a liquid (working oil) is used as the working fluid, a necessary pressure can be easily generated as compared with a configuration using gas.
(6) Since the clamp member 21 is provided with the adjusting bolt 28, it can cope with workpieces W having different shapes and sizes.

  (7) The clamp device 15 and the pump unit 31 are provided on a support plate 14 fixed on the table 13. Therefore, by fixing the support plate 14 to which the clamp device 15 and the pump unit 31 are assembled on the table 13, the assembly of the device is easier than when the clamp device 15 and the pump unit 31 are directly assembled on the table 13. become.

  (8) A flow path 37 for supplying the working fluid from the pump unit 31 to the fluid pressure cylinders 22 and 23 is formed in the support plate 14. Therefore, unlike the case where piping is used, the piping is not exposed on the surface of the support plate 14.

  (9) Generally, the machining center main body 12 of the machining center 11 has a larger space than the range necessary for the movement of the table 13, so that even if the area of the table 13 is increased so that the pump unit 31 can be mounted, the machining center The space required for installing 11 will not be widened. Therefore, space efficiency can be improved as compared with the conventional machining center in which the pump for supplying the hydraulic oil in the fluid pressure cylinders 22 and 23 is provided outside the machining center main body 12.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment is different from the first embodiment in the configuration of the pump unit and the fluid pressure generating mechanism, and the other configurations are the same. Therefore, the detailed description of the same parts is omitted. .

  As shown in FIG. 4, the fluid pressure generating mechanism 43 provided in the pump unit 42 is constituted by a pump that generates fluid pressure by reciprocating movement of a rod 44 as a drive shaft. In this embodiment, a plunger pump is used. ing. The pump unit 42 is provided with a chamber 45 extending along the X direction (the left-right direction in FIG. 4) in the moving direction of the table 13. The rod 44 protrudes from an end surface of a piston 46 slidably disposed in the chamber 45, and is urged by a coil spring 47 so that an end 44 a protrudes outside the pump unit 42.

  The suction port 43a of the fluid pressure generating mechanism 43 is communicated with the tank 34 via a communication passage 48, and a check valve 49 is provided in the communication passage 48 to prevent the hydraulic oil from flowing back to the tank 34 side. The tank 34 is opened to atmospheric pressure through a passage (not shown). The discharge port 43 b of the fluid pressure generating mechanism 43 is communicated with the ports 22 d and 23 d of the fluid pressure cylinders 22 and 23 through the flow path 37. A release valve 39 is provided in the middle of a branch path 37 a that connects the flow path 37 and the tank 34.

  The machining center main body 12 is provided with a contact portion 50 capable of contacting the rod 44 at a position near the end of the moving range in the X direction (left and right direction in FIG. 4) of the table 13. Accordingly, when the table 13 moves in the X direction so as to approach the contact portion 50, the rod 44 comes into contact with the contact portion 50 during the movement. When the table 13 moves forward in the X direction (moving in the right direction in FIG. 4) while the rod 44 is in contact with the abutting portion 50, the piston 46 moves relative to the left in FIG. The hydraulic oil in the chamber 45 is discharged from the discharge port 43b to the flow path 37. When the table 13 moves backward in the X direction (moving leftward in FIG. 4) while the rod 44 is in contact with the abutting portion 50, the piston 46 relatively moves in the chamber 45 rightward in FIG. The hydraulic oil in the tank 34 is sucked into the chamber 45. That is, when the table 44 reciprocates in the X direction while the rod 44 is in contact with the contact portion 50, hydraulic oil is discharged from the discharge port 43 b and is supplied to the fluid pressure cylinders 22 and 23 through the flow path 37. Supplied. The pressurized state of the hydraulic oil supplied to the flow path 37 is maintained while the spool 40 is disposed at the blocking position as in the case of the first embodiment. And if the small diameter part 40a of the spool 40 is arrange | positioned in the position corresponding to the branch path 37a, it will be in the state which connected the flow path 37 to the tank 34, and a pressurization state will be cancelled | released.

  In this embodiment, when the workpiece W is clamped by the clamping device 15, the operator first sets the workpiece W at a predetermined position on the support plate 14. Next, the operation panel 19 is operated to input a command for reciprocating the table 13 in the X direction in a state where the rod 44 of the fluid pressure generating mechanism 43 is in contact with the contact portion 50. As a result, with the rod 44 in contact with the contact portion 50, the table 13 is reciprocated in the X direction, and the fluid pressure generating mechanism 43 is driven. Then, pressurized hydraulic fluid is supplied to the fluid pressure cylinders 22 and 23, and the workpiece W is clamped by the clamp member 21 of the clamp device 15. The table 13 reciprocates a preset number of times and then returns to a predetermined position when machining the workpiece W.

  When releasing the clamping state of the workpiece W by the clamping device 15, as in the case of the first embodiment, the operation panel 19 is operated and the spool 40 of the release valve 39 is moved using the downward movement of the main shaft 16. The small diameter portion 40a is moved down to a position corresponding to the branch path 37a. As a result, the flow path 37 is in communication with the tank 34, the clamp member 21 is rotated in a direction away from the work W, and the clamp state of the work W by the clamp device 15 is released.

This embodiment has the following effects in addition to the same effects as the effects (1), (2), (4) to (9) in the first embodiment.
(10) The fluid pressure generating mechanism 43 is a pump that generates fluid pressure by reciprocating the drive shaft (rod 44), and the end 44a of the rod 44 is fixed at a predetermined position of the machining center 11 when the table 13 is reciprocated. It is configured to be able to reciprocate by contact with the contact portion 50. Therefore, the fluid pressure generating mechanism 43 can be driven regardless of the configuration on the main shaft 16 side. Further, the tool 20 necessary for the machining operation can be mounted on the spindle 16 while the workpiece W is being clamped by moving the table 13 without waiting for the end of the clamping operation.

(11) Since a plunger pump is used as the fluid pressure generating mechanism 43, the configuration can be simplified as compared with the diaphragm pump.
In addition, you may change said each embodiment into another embodiment (another example) as follows.

  In the case where the fluid pressure generating mechanism is constituted by a pump that generates fluid pressure by reciprocating movement of the drive shaft, the following method may be used. That is, when the end portion of the drive shaft is reciprocated in the axial direction of the main shaft 16, the main shaft 16, the tool 20 that is rotated and stopped while being mounted on the main shaft 16, and the main shaft 16 are supported and integrated with the main shaft 16. The main shaft support portion 16a reciprocally moves (see FIG. 4) or is pressed by a pressing member attached to the main shaft support portion 16a. Thus, the drive shaft of the fluid pressure generating mechanism is configured to be able to reciprocate in the axial direction of the main shaft 16.

  For example, when the end of the drive shaft is pressed by the main shaft 16, as shown in FIG. 5, a pump unit 42 including a fluid pressure generating mechanism 43 similar to the fluid pressure generating mechanism 43 in the second embodiment is used. The rod 44 is provided so as to move in the vertical direction, and the rod 44 is driven by pressing the end 44 a of the rod 44 with the lower end of the main shaft 16. In this case, since the nut runner 33 is unnecessary as compared with the first embodiment, the operation of mounting the nut runner 33 on the main shaft 16 is not necessary in the clamping process of the workpiece W.

  When the end of the drive shaft is pressed with the tool 20 attached to the main shaft 16, the rotation of the main shaft 16 is stopped. Moreover, when pressing with the tool 20, it is preferable to press in parts other than the blade part of the tool 20. FIG. Further, when pressing with the main shaft support portion 16a, it is preferable to press with the shoulder portion 16b (see FIG. 4) constituting the lower end portion of the main shaft support portion 16a, and for pressing attached to the main shaft support portion 16a. As a member, a member having an arbitrary shape can be attached as long as the end of the drive shaft can be pressed during the reciprocating movement of the main shaft 16 in the axial direction.

  -The pump which generates fluid pressure by rotation of the drive shaft 32 used as the fluid pressure generation mechanism 30 like the pump unit 31 in 1st Embodiment is not restricted to a turbo pump, For example, a gear pump is used. Also good.

  -Like the pump unit 42 in 2nd Embodiment, the pump which generate | occur | produces a fluid pressure by the reciprocating movement of the drive shaft (rod 44) used as the fluid pressure generation mechanism 43 is not restricted to a plunger pump, For example, a diaphragm A pump may be used.

  The release valve 39 is not limited to the configuration in which the operation is performed by the main shaft 16. For example, the release valve 39 is disposed horizontally and the operated portion 40b of the spool 40 is pressed by using the movement of the table 13. Specifically, as shown in the first embodiment or FIG. 5, in the configuration in which the fluid pressure generating mechanisms 30 and 43 are driven by the main shaft 16, the workpiece 20 is processed by the tool 20 by the main shaft 16. When the table 13 is moved outside the range where the table 13 is disposed, a contact portion is provided at a position that can be engaged with the operated portion 40b. Further, in the case of the configuration in which the fluid pressure generating mechanism 43 is driven using the movement of the table 13 as in the second embodiment, the table 13 is outside the moving range for driving the fluid pressure generating mechanism 43. A contact portion that can be engaged with the operated portion 40b when moving is provided. Alternatively, the contact portion is provided so as to be movable at a position where the contact portion can be engaged with the end portion 44 a of the rod 44 and a position where the contact portion 40 b of the spool 40 can be engaged.

The present invention is not limited to a machining center in which a plurality of types of tools 20 are replaced by the auto tool changer ATC, but is applied to a machining center in which the tool mounted on the spindle 16 is manually replaced.
The clamp device 15 and the pump units 31 and 42 may be directly fixed on the table 13 without providing the support plate 14.

  The table 13 is not limited to a configuration that can be moved in the X direction and the Y direction, but may be configured to be movable only in one direction of the X direction and the Y direction, or may be configured to perform a rotational movement without performing a linear movement. .

The table 13 may be configured such that the main shaft 16 can move in the X direction and the Y direction in addition to the rotation and the lifting operation without moving.
The fluid pressure generating mechanisms 30 and 43 may use gas (for example, air) as a working fluid.

-You may utilize the wall of the machining center main body 12 as the contact part 50 in 2nd Embodiment.
-The release valve 39 may be operated manually.

A pipe may be used instead of forming the flow path 37 for supplying the working fluid from the pump units 31 and 42 to the fluid pressure cylinders 22 and 23 in the support plate 14.
-The machining center is not limited to a vertical machining center, and may be applied to a horizontal machining center.

The following technical idea (invention) can be understood from the embodiment.
(A) In the invention according to any one of claims 1 to 6, the fluid pressure device and the fluid pressure generating mechanism are provided on a support plate fixed on the table.

The schematic cross section which shows the pump unit and clamp apparatus of 1st Embodiment. The model perspective view of a machining center. The model perspective view which shows the relationship between a main axis | shaft, a nut runner, and a pump unit. The partial schematic cross section which shows the pump unit and clamp apparatus of 2nd Embodiment. The schematic cross section of the pump unit in another embodiment.

Explanation of symbols

  W ... Workpiece, 11 ... Machining center, 12 ... Machining center body, 13 ... Table, 15 ... Clamping device, 16 ... Main shaft, 16a ... Main shaft support part, 20 ... Tool, 21 ... Clamp member as pressing part, 22, 23 ... Fluid Fluid pressure cylinders as pressure devices, 22d, 23d ... ports, 30, 43 ... fluid pressure generating mechanism (pump), 30b, 43b ... discharge ports, 31 ... pump units as fluid pressure generating devices, 32 ... drive shafts, 32a ... upper end part as end part, 33 ... nut runner as rotation tool, 34 ... tank, 37 ... flow path, 37a ... branch path, 38, 49 ... check valve, 39 ... release valve, 44a ... end part, 50 ... contact part.

Claims (14)

A table on which the workpiece is supported and a main shaft for performing work on the workpiece supported on the table are configured to be relatively movable, and a hydraulic device driven by a working fluid is provided on the table. At the machining center
A fluid pressure generating mechanism for pressurizing the working fluid supplied to the fluid pressure device is provided on the table, and the fluid pressure generating mechanism is driven using at least one of the operation of the main shaft and the movement of the table. A machining center characterized by The fluid pressure generating mechanism is a pump that generates fluid pressure by rotation of a drive shaft, and the drive shaft is connected to the main shaft via a rotation tool whose end is detachably attached to the main shaft. The machining center according to claim 1, wherein the machining center is configured to be rotatable together with the main shaft. The fluid pressure generating mechanism is a pump for generating fluid pressure by reciprocating movement of a drive shaft, and the drive shaft is attached to the main shaft and the main shaft at the end portion when reciprocating in the axial direction of the main shaft. The shaft of the main shaft is pressed by a tool whose rotation is stopped in a state, a main shaft support portion that supports the main shaft and reciprocates integrally with the main shaft, or a pressing member attached to the main shaft support portion. The machining center according to claim 1, wherein the machining center is configured to be reciprocally movable in a direction. The table is provided so as to be movable relative to a machining center main body supporting the table, the fluid pressure generating mechanism is a pump for generating fluid pressure by reciprocating movement of a drive shaft, and the drive shaft has an end portion thereof. 2. The machining center according to claim 1, wherein the table is configured to be reciprocally movable in a reciprocating direction of the table by abutting against a contact portion provided on the side of the machining center main body when the table is reciprocated. 3. The machining center according to any one of claims 1 to 4, wherein the fluid pressure device is a fluid pressure cylinder that operates a clamp member that holds the workpiece between a clamp position and an unclamp position. The fluid pressure cylinder is a single-acting cylinder with a spring, and the working fluid flows back to the pump side in the middle of the flow path connecting the discharge port of the pump constituting the fluid pressure generating mechanism and the port of the fluid pressure cylinder. A check valve is provided, and a branch passage is provided near the fluid pressure cylinder from the check valve of the flow passage to communicate with the tank connected to the atmosphere. Is provided with a release valve that can be switched between an open state that allows the branch passage to communicate with the tank and a shut-off state that blocks the communication, and the release valve is always maintained in the shut-off state and the axial direction of the main shaft. The machining center according to claim 5, wherein the machining center is configured to be switched to an open state by using movement to the position. A fluid pressure generating device that pressurizes working fluid supplied to a fluid pressure device that is provided on a table of a machining center on which a workpiece is supported and is driven by the working fluid,
The fluid pressure generating device includes a fluid pressure generating mechanism provided on the table, the fluid pressure generating mechanism has a drive shaft, and the drive shaft generates fluid pressure by rotating or reciprocating in the axial direction. A fluid pressure generator configured to be configured to be capable of rotating or reciprocating in the axial direction by a force applied from the outside of the fluid pressure generator. The fluid pressure generating mechanism is a pump that generates fluid pressure by rotation of a drive shaft, and the drive shaft is coupled to the main shaft via a rotation tool whose end is detachably attached to the main shaft in a machining center. The fluid pressure generator according to claim 7, wherein the fluid pressure generator is configured to be rotatable together with the main shaft. The fluid pressure generating mechanism is a pump for generating fluid pressure by reciprocating movement of a drive shaft, and the drive shaft is attached to the main shaft and the main shaft at the end portion when reciprocating in the axial direction of the main shaft. The shaft of the main shaft is pressed by a tool whose rotation is stopped in a state, a main shaft support portion that supports the main shaft and reciprocates integrally with the main shaft, or a pressing member attached to the main shaft support portion. The fluid pressure generating device according to claim 7, wherein the fluid pressure generating device is configured to be capable of reciprocating in a direction. The fluid pressure generating mechanism is a pump that generates fluid pressure by reciprocating movement of a drive shaft, and the drive shaft is in contact with a machining center main body that supports the table when the table is reciprocated. The fluid pressure generating device according to claim 7, wherein the fluid pressure generating device is configured to reciprocate in a reciprocating direction of the table by abutting with a portion. A table on which the workpiece is supported; a clamp device that fixes and supports the workpiece with a clamp member driven by a working fluid; and a spindle that performs an operation on the workpiece with a tool that is detachably mounted. A clamping method in which a spindle clamps a workpiece in a machining center configured to be movable relative to the table,
The clamp device includes a pressing portion that contacts and clamps the workpiece, and a fluid pressure cylinder that causes the pressing portion to perform a clamping operation and a clamping release operation,
The fluid pressure generating mechanism that supplies the working fluid to the fluid pressure cylinder is a pump that generates fluid pressure by driving a drive shaft that is driven using at least one of the operation of the main shaft and the movement of the table, A check valve that prevents backflow of the working fluid to the pump side and a release valve that can be operated by the main shaft are provided in the middle of the flow path that connects the discharge port of the pump and the port of the fluid pressure cylinder. And
The clamping operation of clamping the workpiece by the clamping device includes a fluid pressure generating step of generating a fluid pressure by driving the pump using at least one of the operation of the main shaft and the movement of the table, A clamping step of supplying the fluid pressure cylinder and bringing the pressing portion into contact with the workpiece,
The clamp release operation for releasing the workpiece clamped by the clamp device includes a pressure release step of releasing the pressure of the working fluid supplied to the fluid pressure cylinder by operating the release valve by the main shaft. A clamping method characterized by comprising: The fluid pressure generation mechanism is a pump that generates fluid pressure by rotation of a drive shaft. In the fluid pressure generation step, an end portion of the drive shaft is attached via a rotation tool that is detachably attached to the main shaft. The clamping method according to claim 11, wherein the drive shaft is rotated together with the main shaft by being coupled to the main shaft. The fluid pressure generating mechanism is a pump that generates fluid pressure by reciprocating movement of the drive shaft. In the fluid pressure generating step, the main shaft is moved when the end of the drive shaft is reciprocated in the axial direction of the main shaft. The tool is stopped by rotation while being mounted on the main shaft, the main shaft support portion that supports the main shaft and reciprocates integrally with the main shaft, or is pressed by a pressing member attached to the main shaft support portion. Accordingly, the drive shaft is reciprocated in the axial direction of the main shaft. The table is provided so as to be movable relative to the machining center main body, and the fluid pressure generating mechanism is a pump that generates fluid pressure by reciprocating movement of the drive shaft. In the fluid pressure generating step, an end of the drive shaft is provided. The driving shaft is reciprocated in the reciprocating direction of the table by abutting a contact portion provided on a machining center main body supporting the table when the table is reciprocated. Clamping method.

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