Tool bench and machine tool

Abstract

To mount a non-rotating tool on a tool table that can rotate the tool via a gear train with backlash, and to prevent the tool from wobbling due to backlash when the tool is stopped and in use without complicating the structure, the tool comprises: a spindle (33) that holds the cutting tool (85) in a manner that allows it to be loaded and unloaded in the direction of axis (C3); a gear train (33) that transmits rotation to the held cutting tool (85); a pull rod (34) that moves the cutting tool (85) in the direction of axis (C3); and a piston (36) configured to move in the direction of axis (C3) between a rearmost position and a foremost position, wherein a coupling (convex-concave shape (36c, 34c)) is formed between the piston (36) and the pull rod (34) that allows them to rotate integrally in a contact state, and the piston (36) stops at an intermediate position between the rearmost position and the foremost position.

Description

Cross-references to related applications

[0001] This application claims priority based on Japanese Patent Application No. 2023-207519 filed with the Japan Patent Office on December 8, 2023, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] The present invention relates to a tool table and a machine tool having the tool table. Background Technology

[0003] A tool table and a machine tool having the tool table are known. A tool holder is rotatably mounted on the tool table. The tool holder holds a rotary tool that processes a workpiece by rotation in a detachable manner. By driving the tool holder, on which the rotary tool is mounted, to rotate, the rotary tool processes a specified workpiece.

[0004] The machine tool has a drawbar on the tool table as a tool loading and unloading operation member. The drawbar is integral with the tool holding part in the rotation direction and can move freely in and out of the tool holding part in the rotation axis direction. It has a piston as an operation driving member to drive the drawbar to move forward and backward. By pressing the drawbar with the piston, the drawbar can be moved, thereby removing the rotating tool from the tool holding part for tool replacement (for example, see Patent Document 1).

[0005] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 7-040104 Summary of the Invention The problem the invention aims to solve Sometimes, this machine tool needs to restrict the rotation of the tool holder and fix the rotational direction of the tool in the tool mounting section. For example, consider situations where a fixed tool, such as a lathe tool, is mounted in the tool holder to replace the rotating tool, allowing the fixed tool to perform contour machining or boring on a rotating workpiece without rotating it, and where the rotating tool is held in phase. However, there is a problem that it is not easy to fix the rotational direction of the tool in the tool mounting section.

[0006] The present invention was made in view of the above circumstances, and its object is to provide a tool table and a machine tool having the tool table that can prevent positional displacement of a tool held by a tool holder in the rotational direction with a simple structure.

[0007] means for solving problems The first aspect of the present invention is a tool table, comprising: a tool holding portion for holding a tool for machining a workpiece in a detachable manner, which can rotate freely about an axis of the tool; a tool loading / unloading operation member configured to be integrally formed with the tool holding portion in the rotational direction about the axis and to be freely movable relative to the tool holding portion in the axial direction of the tool; and an operation drive member for driving the loading / unloading operation member to move in and out. The tool table rotates the tool holding portion on which the tool is mounted by driving it, and the workpiece is machined by the tool. The tool can be unloaded from the tool holding portion by pressing the loading / unloading operation member with the operation drive member to move it in the axial direction. A position is provided within the movement range of the operation drive member, forming a state in which the operation drive member abuts against the loading / unloading operation member and restricts the rotation of the loading / unloading operation member.

[0008] A second aspect of the present invention is a machine tool comprising: a spindle, a workpiece holder, a tool table of the present invention, and a control unit that controls the various actions of the spindle and the tool table; the control unit is capable of stopping the operation drive member at: a position separated from the loading / unloading operation member; a position where the loading / unloading operation member can load / unload the tool; and a position in which the operation drive member abuts against the loading / unloading operation member, thereby restricting the rotation of the loading / unloading operation member.

[0009] Invention Effects The tool table and machine tool having the tool table of the present invention, by positioning the operation drive member in a position abutting against the loading / unloading operation member, allows the loading / unloading operation member to be positioned to hold the tool, thus easily restricting the rotation of the tool mounting part and fixing the tool mounting part without complicating the structure. Therefore, for example, when the tool is stopped and the workpiece is being machined, it is possible to prevent positional deviation of the tool in the rotational direction, prevent a decrease in machining accuracy, and maintain and preserve the phase of the tool in the rotational direction as needed. Attached Figure Description

[0010] Figure 1 It is a schematic 3D diagram of an automatic lathe.

[0011] Figure 2 This is a three-dimensional view of the interior of an automatic lathe as seen from the machining room side.

[0012] Figure 3A This is a cross-sectional view showing the vertical plane of the tool spindle, including shaft C3, showing the piston in its forward position.

[0013] Figure 3B It is shown in detail Figure 5A A magnified view of part A in the image.

[0014] Figure 4A This is a sectional view showing the vertical plane of the tool spindle, including shaft C3, with the piston in the intermediate position.

[0015] Figure 4B It is shown in detail Figure 4A A magnified view of part A in the image.

[0016] Figure 5A This is a sectional view showing the vertical plane of the tool spindle, including shaft C3, with the piston in the rearmost position.

[0017] Figure 5B It is shown in detail Figure 3A A magnified view of part A in the image.

[0018] Figure 6 It shows along Figure 3A , 4A A sectional view of the vertical plane of line BB in 5A.

[0019] Figure 7 It shows along Figure 3A , 4A A sectional view of the vertical plane of line CC in 5A.

[0020] Figure 8 It is a schematic three-dimensional view showing the concave and convex shapes formed on the front surface of the piston.

[0021] Figure 9A It is a side view schematically showing the concave and convex shapes of the piston and the connecting rod, showing the state in which the front surface of the piston is separated from the rear end face of the connecting rod.

[0022] Figure 9B This is a schematic side view showing the concave and convex shapes of the piston and the connecting rod, indicating that the front surface of the piston is in contact with the rear end face of the connecting rod and that the concave and convex shapes of the piston and the connecting rod are engaged with each other. Detailed Implementation

[0023] Figure 1 The automatic lathe 100 shown is one embodiment of the machine tool of the present invention. For example... Figure 2 As shown, the automatic lathe 100 has a spindle 10, a comb-shaped tool post 20, and a tool spindle 30, which is an example of the tool table of the present invention, inside the cover.

[0024] The automatic lathe 100 is operated based on the operation panel 90, and the movement of the spindle 10, comb-shaped tool post 20 and tool spindle 30 is controlled by the control unit 80 housed in the cover below the operation panel 90.

[0025] The main shaft 10 is supported to move freely in the z-axis direction parallel to the axis and is driven to rotate about axis C1.

[0026] A guide bushing 55 is provided on the guide bushing support table 51 located in front of the spindle 10, and the front end of the workpiece held by the spindle 10 protrudes from the guide bushing 55 into the machining chamber 50.

[0027] The comb-shaped tool holder 20 and the tool spindle 30 are arranged inside the machining chamber 50. The comb-shaped tool holder 20 supports multiple tools 21, 22...25.

[0028] The comb-shaped tool post 20 moves along the y-axis, which is orthogonal to the z-axis, so that the automatic lathe 100 selects one of the tools 21...25 for machining. The comb-shaped tool post 20 moves along the x-axis, which is orthogonal to both the z-axis and the y-axis, so that the selected tool 21...25 performs turning machining on the workpiece.

[0029] like Figure 3A As shown, a rotary tool 86 and a cutting tool 85 integrally mounted on a cage are mounted on the tool spindle 30. The rotary tool 86 is inserted into the tool drive shaft in a freely detachable manner, and the tool drive shaft is supported by the body of the tool spindle 30 for free rotation. The cutting tool 85 is mounted below the tool drive shaft on the spindle 33, which is supported for free rotation about axis C3.

[0030] By moving the tool spindle 30 along the x-axis, either a cutting tool 85 or a rotary tool 86 can be selected as the tool for machining the workpiece. By moving the tool spindle 30 along the y-axis, the workpiece can be machined by the selected cutting tool 85 or rotary tool 86.

[0031] The tool spindle 30 can rotate about an axis C2 parallel to the x-axis, enabling the cutting tool 85 or the rotary tool 86 to machine the workpiece in an inclined position relative to the y-axis.

[0032] The movement of the tool spindle 30 along the x-axis, the movement along the y-axis, the rotation around axis C2, and the rotation of the cutting tool 85 and the rotary tool 86 around axis C3 are controlled by the control unit 80.

[0033] like Figure 3A , Figure 4A , Figure 5A As shown, the tool spindle 30 inputs rotational driving force to gear 32a via a bevel gear 32a1 (not shown) inserted into the upper opening 31 and meshing with a drive gear, which drives gear 32b to rotate via a spur gear 32a2. Gear 32b meshes with gear 32c, which is integrally mounted on the tool drive shaft. Gear 32c meshes with gear 32e via a gear (not shown). The rotational drive of gear 32b is sequentially transmitted from gear 32c to gear 32e.

[0034] The tool drive shaft rotates by means of a rotational driving force transmitted to gear 32c, which drives the rotating tool 86 to rotate. Gear 32e is integrally mounted on spindle 33 (an example of a tool holder).

[0035] The spindle 33 is a tool holder that holds the cutting tool 85 so that it can be loaded and unloaded along the axis C3 and allows the cutting tool 85 to rotate freely about the axis C3. The cutting tool 85 is configured such that the tool body 85a is held integrally by a retainer 85b via a collet chuck. A pull stud 85d is integrally provided on the retainer 85b, and the pull stud 85d protrudes to the opposite side of the tool body 85a.

[0036] The retainer 85b is formed in a conical shape. A conical hole is formed on the inner side of the spindle 33. When the retainer 85b is inserted into the hole of the spindle 33, the inclined surface 85c of the retainer 85b contacts and is in close contact with the inner circumferential surface 33a of the hole, thereby mounting the cutting tool 85 on the spindle 33.

[0037] At the hole of the main shaft 33, on the inner side (deep inside) of the tapered inner circumferential surface 33a, a groove 33b with an inner diameter larger than the inner diameter of the smallest inner diameter portion of the tapered surface is formed around the entire circumference. At the hole of the main shaft 33, a ball pressing portion 33c is formed further inside than the groove 33b, and the ball pressing portion 33c is an inner circumferential surface with an inner diameter smaller than the inner diameter of the groove 33b.

[0038] The pull rod 34 (an example of a loading / unloading operating component) is configured to move (freely advance and retract) along the shaft C3 inside the main shaft 33. At the front end of the pull rod 34 are multiple balls 34a that engage from the outside with pull studs 85d provided in the retainer 85b. A helical spring 35 is provided on the outside of the pull rod 34.

[0039] A helical spring 35 is disposed between a limiting portion integrally formed at the rear end of the pull rod 34 and a stepped portion formed in the hole of the main shaft 33. The pull rod 34 is exerted with a rearward force by the helical spring 35. The rearward movement of the pull rod 34 beyond a predetermined length is limited by abutting against the limiting portion 33d formed by the main shaft 33.

[0040] Pull rod 34 overcomes the force of coil spring 35, such as Figure 3A As shown, when the ball 34a is in a position facing the groove 33b of the spindle 33, the ball 34a is retracted from the inside of the front end of the pull rod 34 to the groove 33b on the outside of the radial direction, allowing the pull stud 85d to be installed on the inside of the front end of the pull rod 34 and to disengage from the inside of the front end of the pull rod 34.

[0041] With the ball 34a retracted from the inner side of the front end of the pull rod 34 to the groove 33b on the outer side in the radial direction, if the retainer 85b is inserted into the hole of the spindle 33 and the cutting tool 85 is mounted on the spindle 33, the pull pin 85d is inserted into the inner side of the front end of the pull rod 34.

[0042] If a cutting tool 85 is mounted on the spindle 33 and the pull rod 34 moves rearward under the force of the helical spring 35, the ball 34a of the pull rod 34 moves from a position facing the groove 33b to a position facing the ball pressing part 33c. The ball 34a, pressed inward in the radial direction by the ball pressing part 33c, becomes a part that protrudes to the inner side of the front end of the pull rod 34 and engages with the pull stud 85d. The retainer 85b of the cutting tool 85 is held by the spindle 33 and becomes an integral part, allowing the cutting tool 85 to rotate integrally with the spindle 33.

[0043] like Figure 6 As shown, with regard to the pull rod 34 and the spindle 33, the spline 34s of the pull rod 34 engages with the spline 34s of the inner circumferential surface of the spindle 33, the pull rod 34 is able to move relative to the spindle 33 along the axis C3, and the rotation of the pull rod 34 about the axis C3 is restricted.

[0044] A cylinder 38 is formed on the outer periphery of the tool spindle 30, behind the spindle 33. A piston 36 (an example of an operating drive member) is disposed within the cylinder 38 so as to freely move forward and backward along the axis C3. The rearwardly projecting rod 36b of the piston 36 passes through a through hole formed in the sealing support member 37 of the tool spindle 30 body, and moves forward and backward along the axis C3. The piston 36 drives the pull rod 34 to move forward and backward.

[0045] like Figure 7 As shown, the outer peripheral surface 36s of the rod portion 36b is formed with a hexagonal cross-sectional profile, and the through hole of the sealing support member 37 is formed as a hexagonal hole with an inner peripheral surface 37s having a hexagonal cross-sectional profile, which corresponds to the hexagonal cross-sectional profile of the rod portion 36b. The rod portion 36b can move relative to the sealing support member 37 along the axis C3, and its rotation about the axis C3 is restricted. The movement of the piston 36 is carried out under the condition that its rotation about the axis C3 is restricted.

[0046] Under the control of the control unit 80, working fluid such as air is supplied to the area on the left side of the piston 36 in the cylinder 38, thereby causing the piston 36 to move forward. Under the control of the control unit 80, working fluid such as air is supplied to the area on the right side of the piston 36 in the cylinder 38, thereby causing the piston 36 to move backward.

[0047] Piston 36, under the control of the aforementioned control unit 80, is able to... Figure 5A , Figure 5BThe position shown is the last position after retreating to the limit. Figure 3A , Figure 3B The piston 36 moves within the range between its forwardmost and ultimate positions, as shown. Furthermore, the control unit 80 controls the piston 36 to stop within the range of movement between its rearmost and ultimate positions. Figure 4A , Figure 4B The specified middle position is shown.

[0048] With the piston 36 in its rearmost position, the front surface 36a separates behind the rear end face 34b of the pull rod 34. In the rearmost position of the piston 36, the cutting tool 85 is held on the spindle 33 by the pull rod 34, and the cutting tool 85 can be rotated or stopped by the spindle 33.

[0049] like Figure 8 As shown, a concave-convex shape 36c is formed on the front surface 36a of the piston 36 facing the rear end face 34b of the rod 34. The concave and convex portions of the concave-convex shape 36c extend radially about the axis C3, and these concave and convex portions alternate at equal intervals along the circumference of the axis C3. Figure 9A , Figure 9B As shown, a concave-convex shape 34c corresponding to the concave-convex shape 36c is formed on the rear end face 34b of the rod 34 facing the front surface 36a of the piston 36.

[0050] The concave-convex shape 36c of the piston 36 and the concave-convex shape 34c of the pull rod 34 can engage with each other.

[0051] If piston 36 from Figure 5A , Figure 5B The state shown, configured at the very back, progresses to... Figure 4A , Figure 4B In the intermediate position shown, the front surface 36a of the piston 36 abuts against the rear end surface 34b of the pull rod 34, becoming... Figure 9B The state in which the concave-convex shape 36c and the concave-convex shape 34c are combined is shown.

[0052] The piston 36 and the pull rod 34 become integrated around the axis C3 through the interlocking of the concave and convex shapes 36c and 34c. When the piston 36 is in the intermediate position, it does not press the pull rod 34 and does not cause it to move in the direction of axis C3. The pull rod 34 stops and does not move forward or backward relative to the spindle 33. The spindle 33 maintains its hold on the cutting tool 85, and the position of the cutting tool 85 in the direction of rotation is maintained.

[0053] In addition, when the piston 36 is in the middle position, it can also press the pull rod 34 to move it within the range that the spindle 33 maintains holding the cutting tool 85.

[0054] The control unit 80 controls the piston 36 to move forward and stop at the foremost position. By pressing the pull rod 34 with the piston 36, the pull rod 34 is moved to a position that allows the pull pin 85d to be installed and dismounted, thereby enabling the tool holder 85b to be mounted and dismounted relative to the spindle 33, and the cutting tool 85 to be mounted and dismounted.

[0055] Furthermore, when the automatic lathe 100 processes a workpiece rotating around axis C1 while the cutting tool 85 is stopped and not rotating, the control unit 80 stops the drive source such as the motor that drives the gear train 32, or does not transmit rotation to the drive gear (not shown) connected to the gear train 32.

[0056] Even when the drive force to the drive gear is stopped so that the rotation drive of the spindle 33 is stopped, the piston 36 is moved to the intermediate position to prevent positional displacement in the rotational direction that may occur due to backlash between the connected gears 32a, 32b, 32c, and 32e. Thus, the cutting tool 85 is fixed and positional displacement in the rotational direction is prevented.

[0057] For example, when a fixed tool such as a lathe tool is mounted on the tool body 85a, which is used as a cutting tool 85, to machine a workpiece that rotates around axis C1, it can prevent the cutting edge of the tool body 85a from shifting from a predetermined position due to friction with the rotating workpiece, or from vibrating due to frictional changes, which is called chattering. It can also prevent the machining accuracy of boring of the workpiece, machining of the outer peripheral surface of the workpiece, etc. from decreasing.

[0058] As detailed above, regarding the automatic lathe 100 of this embodiment, when the tool spindle 30 is used with the fixed tool mounted as the tool body 85a and the spindle 33 is stopped, the simple structure of the piston 36's front surface 36a abutting against the rear end surface 34b of the pull rod 34, and the simple control of the control unit 80 to stop the piston 36 at a predetermined position (intermediate position) within the range between the rearmost and foremost positions, can prevent positional deviation of the tool body 85a in the rotational direction and prevent movement of the cutting edge of the tool body 85a.

[0059] The front surface 36a of the piston 36 and the rear end surface 34b of the rod 34 are formed with concave and convex shapes 36c and 34c as a coupling, so that the concave and convex shapes 36c and 34c engage, and the front surface 36a of the piston 36 abuts against the rear end surface 34b of the rod 34.

[0060] Alternatively, the front surface 36a of the piston 36 and the rear end surface 34b of the rod 34 can be made to have a high coefficient of friction, or components with a high coefficient of friction can be provided on the front surface 36a of the piston 36 and the rear end surface 34b of the rod 34, so that the front surface 36a of the piston 36 and the rear end surface 34b of the rod 34 can abut against each other in a high-friction state, instead of forming concave and convex shapes 36c and 34c on the front surface 36a of the piston 36 and the rear end surface 34b of the rod 34, respectively.

Claims

1. A tool table, wherein, have: The tool holder allows for the detachable holding of the tool used to machine the workpiece, and allows free rotation about the tool's axis. The tool loading and unloading operation member is configured to be integrally formed with the tool holding part in the rotational direction about the axis, and to be able to freely move forward and backward relative to the tool holding part in the axial direction of the tool. Operate the drive component to drive the loading and unloading operation component forward and backward; The tool table rotates by driving the tool holder on which the tool is mounted, allowing the tool to machine the workpiece. The tool can be removed from the tool holder by pressing the loading / unloading operating member against the operating member to move it in the axial direction. The operating drive member is provided with a position within its range of motion that forms a state in which the operating drive member abuts against the loading / unloading operation member, thereby restricting the rotation of the loading / unloading operation member.

2. The tool table according to claim 1, wherein, The surfaces of the operating drive member and the loading / unloading operation member that abut against each other are respectively formed with concave and convex shapes that engage with each other when the operating drive member and the loading / unloading operation member abut against each other.

3. The tool table according to claim 2, wherein, The concave-convex shape is such that the concave and convex portions extend radially from the axis of the operation drive member and the loading / unloading operation member, respectively, and the concave and convex portions alternately at equal intervals along the circumference around the axis.

4. The tool table according to claim 1, wherein, The cross-sectional profile of the outer peripheral surface of the rod portion of the operating drive member and the cross-sectional profile of the inner peripheral surface of the sealing bearing member through which the rod portion passes are formed such that the operating drive member can move along the axial direction and prevent the operating drive member from rotating about the axis.

5. A machine tool, wherein, have: Spindle, holding the workpiece The tool table according to any one of claims 1 to 4, and The control unit controls the various movements of the spindle and the tool table; The control unit can stop the operation drive member at: a position separated from the loading / unloading operation member; or a position where the loading / unloading operation member can load / unload the tool. And the position in which the operation drive member abuts against the loading and unloading operation member, thereby restricting the rotation of the loading and unloading operation member.

Images