JP6420033B2 - Workpiece contact unit and machine tool - Google Patents

Description

  The present invention relates to a workpiece contact unit and a machine tool used for positioning a workpiece.

  The lathe includes a workpiece contact unit and a chuck. The workpiece is held by the chuck while being in contact with the workpiece contact unit. In other words, the workpiece contact unit positions the workpiece during processing. The workpiece contact unit includes a jig and a jig receiving member. The jig is detachably attached to the jig receiving member. Specifically, an uneven portion (inlay) is set between the jig and the jig receiving member. The jig is attached to the jig receiving member by fitting the uneven portions. The jig can be exchanged according to the type of workpiece.

Japanese Patent Laid-Open No. 9-123055

  However, the jig replacement operation for the jig receiving member is performed manually by the operator. For this reason, depending on the skill of the operator, the alignment accuracy of the jig (attachment accuracy of the jig to the jig receiving member) may be reduced. The position of the workpiece during machining depends on the position of the jig. For this reason, when the alignment accuracy of the jig is low, the machining accuracy of the workpiece is lowered. Further, in order to ensure the alignment accuracy of the jig, the fitting tolerance of the uneven portion set between the jig and the jig receiving member is extremely small. For this reason, the replacement work is complicated.

  On the other hand, the chuck is used when holding the workpiece positioned by the workpiece contact unit. For example, Patent Document 1 discloses an outer diameter collet chuck that holds a workpiece from the radially outer side. The outer diameter collet chuck includes an auxiliary collet and a connecting face plate. An uneven portion is set between the auxiliary collet and the connecting face plate. The auxiliary collet is attached to the connecting face plate by fitting the uneven portions. The auxiliary collet can be exchanged according to the type of workpiece (outer diameter).

  The auxiliary collet of Patent Document 1 is for holding a workpiece. Further, the above-described problem that occurs during the jig replacement operation also occurs during the auxiliary collet replacement operation. That is, depending on the skill of the operator, the alignment accuracy of the auxiliary collet (attachment accuracy of the auxiliary collet with respect to the connecting face plate) may be reduced. Moreover, when the fitting tolerance of the uneven | corrugated | grooved part set between the auxiliary collet and the connection faceplate is very small, replacement | exchange work is complicated.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a workpiece contact unit and a machine tool with high jig alignment accuracy and easy jig replacement.

  (1) In order to solve the above-described problem, a workpiece contact unit according to the present invention is a collet member and is aligned with the collet member coaxially by the expansion and contraction deformation of the collet member in the radial direction, and contacts the workpiece. And a jig.

  The workpiece contact unit of the present invention performs positioning (centering and alignment) of a jig using a collet member. For this reason, the alignment accuracy of the jig is high. Therefore, the machining accuracy of the workpiece can be increased. In addition, the jig alignment operation and, in turn, the jig replacement operation are simple.

  (1-1) In the configuration of (1), the collet member has a collet cylinder portion having a collet-side taper portion, and the jig is arranged on both sides in the radial direction of the collet cylinder portion. A collet restricting member having a restricting side tapered portion, the collet restricting member moves in the axial direction relative to the collet member, and the restricting side tapered portion slides relative to the collet side tapered portion. It is preferable that the collet tube expands or contracts in the radial direction by moving. According to this configuration, the jig can be aligned by moving the collet regulating member in the axial direction with respect to the collet member.

  (2) In the configuration of (1), it is preferable that the jig has a cylindrical shape, and the collet member is configured to align the jig from the radially inner side. According to this configuration, the jig can be aligned by expanding and deforming the collet member on the radially inner side of the jig.

  (3) In order to solve the above-mentioned problem, a machine tool according to the present invention includes a workpiece contact unit configured as described in (1) or (2) above, and a workpiece holding unit that holds the workpiece. To do. According to this configuration, the workpiece in contact with the jig can be held by the workpiece holding unit.

  (3-1) In the configuration of (3), the jig is a kelay jig that transmits a rotational force to the work, and the work holding portion is on the opposite side of the keley jig across the work. It is better to adopt a structure that is a core push stand that is arranged in contact with the workpiece. According to this configuration, the workpiece can be held between the kelay jig and the core presser during machining. Moreover, a workpiece | work can be rotated with a keley jig.

  According to the present invention, it is possible to provide a workpiece contact unit and a machine tool with high jig alignment accuracy and easy jig replacement work.

It is a left-right direction sectional view of the headstock of the machine tool of a first embodiment. It is a right view of the headstock. It is an enlarged view in the frame III of FIG. It is a schematic diagram of the workpiece | work contact unit of 1st embodiment in the jig | tool set process of a jig | tool attachment method. It is a schematic diagram of the workpiece contact unit in the alignment step of the jig mounting method. It is a cross-sectional view in the left-right direction of the headstock and the tailstock of the machine tool of the second embodiment.

  Embodiments of a workpiece contact unit and a machine tool according to the present invention will be described below.

<First embodiment>
[Configuration of machine tool]
First, the configuration of the machine tool (horizontal lathe) of this embodiment will be described. FIG. 1 shows a cross-sectional view in the left-right direction (spindle direction) of the head stock of the machine tool of this embodiment. FIG. 2 shows a right side view of the headstock. FIG. 3 shows an enlarged view in the frame III of FIG. However, FIG. 3 shows a state in which the lever 434 swings as shown by a dotted line in FIGS. As shown in FIGS. 1 to 3, the head stock 2 of the machine tool 1 according to the present embodiment includes a work contact unit 3 and a work holding unit 4.

(Work contact unit 3)
The work contact unit 3 includes a collet member 30, three cylinder guide members 31, a mandrel guide member 32, a jig receiving member 33, a jig 34, a mandrel 35, and a housing 36. ing. The mandrel 35 is included in the concept of the “collet regulating member” having the configuration (1-1).

  The housing 36 includes a sleeve 360, a central shaft guide member 361, a case 362, and an end plate 363. The sleeve 360 has a cylindrical shape. The sleeve 360 extends in the left-right direction. The central shaft guide member 361 has a disk shape. The central shaft guide member 361 covers the right end opening of the sleeve 360. A guide hole 361 a extending in the left-right direction is opened at the radial center of the central shaft guide member 361. The case 362 has a cup shape opening to the right side (work side). The case 362 is disposed on the right side of the central shaft guide member 361. A guide hole 362a extending in the left-right direction is formed at the radial center of the bottom wall of the case 362. The end plate 363 has a disk shape. The end plate 363 covers the opening of the case 362. A mandrel mounting hole 363a extending in the left-right direction is formed in the center of the end plate 363 in the radial direction. A threaded portion 363aa is formed on the inner peripheral surface of the mandrel mounting hole 363a. In the vicinity of the outer peripheral edge of the end plate 363, a cylinder insertion hole 363b extending in the left-right direction is opened. Three cylinder insertion holes 363b are arranged at 120 ° intervals in the circumferential direction. Inside the housing 36, a work holding portion accommodating portion 36a is defined.

  The collet member 30 includes a collet tube part 300 and a flange part 301. The flange portion 301 is disposed on the right side of the end plate 363. The collet cylinder part 300 protrudes from the flange part 301 to the right side. As shown in FIG. 2, the collet tube portion 300 is formed with six slits S extending in the left-right direction. For this reason, the collet cylinder part 300 can be expanded and contracted in the radial direction. A collet side taper portion 300 a is disposed at the right end (tip) of the collet cylinder portion 300. The collet-side taper portion 300a has a tapered shape that decreases in diameter from the right side (tip side) toward the left side (root side).

  The mandrel guide member 32 has a cylindrical shape. The mandrel guide member 32 is disposed on the radially inner side of the collet member 30 and on the radially outer side of the mandrel mounting hole 363a. The jig receiving member 33 has a cylindrical shape. The jig receiving member 33 is disposed on the right side of the flange portion 301 and on the radially outer side of the collet tube portion 300. The jig 34 has a ring shape. The jig 34 is disposed on the right side of the jig receiving member 33. As shown by hatching in FIG. 2, the left surface of the workpiece W is in contact with the right surface (top surface) of the jig 34. As shown in FIG. 2, two positioning pins 340 protrude from the right surface of the jig 34. The two positioning pins 340 are inserted into the two concave portions W1 of the workpiece W. Depending on the type (for example, dimensions) of the workpiece W, the jig 34 can be replaced.

  The mandrel 35 includes a small-diameter portion 350, a large-diameter portion 351, and a regulation-side taper portion 352 from the left side toward the right side. The small diameter portion 350 is disposed on the radially inner side of the mandrel mounting hole 363a. A screw part 350 a is formed on the outer peripheral surface of the small diameter part 350. The screw portion 350a of the mandrel 35 is screwed with the screw portion 363aa of the end plate 363. The large-diameter portion 351 is disposed on the radially inner side of the mandrel guide member 32. The regulation-side taper portion 352 protrudes to the right from the mandrel guide member 32. The regulation-side taper portion 352 has a tapered shape that decreases in diameter from the right side to the left side. The regulation side taper part 352 is slidable with respect to the collet side taper part 300a. A concave portion 352a is formed on the right surface of the regulation-side taper portion 352. The recess 352a can be engaged with a hexagon wrench.

  The three cylinder guide members 31 protrude from the right side of the end plate 363. The cylinder guide member 31 has a cylindrical shape. The space on the radially inner side of the cylinder guide member 31 is continuous with the cylinder insertion hole 363b.

(Work holding part 4)
The work holding part 4 is disposed in the work holding part accommodating part 36a. The work holding unit 4 includes a central shaft 40, a stepped sleeve 41, a branching member 42, and three finger portions 43.

  The central shaft 40 extends in the left-right direction. The central shaft 40 is disposed on the radially inner side of the sleeve 360. The stepped sleeve 41 is attached to the right end of the central shaft 40. The outer peripheral surface of the stepped sleeve 41 is in sliding contact with the inner peripheral surfaces of the guide holes 361a and 362a. The branch member 42 has a Y-shape when viewed from the right side. That is, the branching member 42 includes three branch portions 420 that extend radially and are separated from each other by 120 ° in the circumferential direction. A sleeve mounting hole 421 extending in the left-right direction is opened at the radial center of the branch member 42. At the radially outer ends of the three branch portions 420 of the branch member 42, shaft attachment holes 422 extending in the left-right direction are formed.

  Each of the three finger portions 43 includes a shaft 430, a guide pin 431, a cylinder 432, a coil spring 433, and a lever 434. The shaft 430 is inserted into the shaft attachment hole 422. The shaft 430 protrudes from the branch member 42 on the right side. The guide pin 431 is disposed at the right end of the shaft 430. The guide pin 431 penetrates the shaft 430 in the radial direction.

  The cylinder 432 has a bottomed cylindrical shape that opens to the left. The cylinder 432 is inserted through the cylinder insertion hole 363 b and the cylinder guide member 31 in the radial direction. Two pin guide grooves 432 a are formed on the side peripheral wall of the cylinder 432. The pin guide groove 432a extends in an oblique direction (a direction having a circumferential component and an axial component). At the left end of the cylinder 432, a flange portion 432b is formed. The flange portion 432b is disposed on the left side of the end plate 363. The outer diameter of the flange portion 432b is larger than the inner diameter of the cylinder insertion hole 363b. The shaft 430 is inserted into the cylinder 432. Both ends of the guide pin 431 in the axial direction are accommodated in two pin guide grooves 432a. The coil spring 433 is inserted into the cylinder 432. The coil spring 433 is in elastic contact with the right end of the shaft 430 and the bottom wall of the cylinder 432. The lever 434 is disposed at the right end of the cylinder 432. The lever 434 is in contact with the right surface of the workpiece W. That is, the workpiece W is held on the head stock 2 by the lever 434 while being positioned on the jig 34.

[Movement during workpiece exchange]
Next, the movement of the machine tool according to this embodiment when the workpiece is replaced will be described. When removing the workpiece W from the headstock 2, first, a machine tool control device (not shown) moves the central shaft 40 to the right. As shown in FIG. 1, a gap C <b> 1 is defined between the flange portion 432 b and the end plate 363. For this reason, when the central shaft 40 is moved to the right side, the stepped sleeve 41, the branch member 42, and the three finger portions 43 are moved to the right side by the gap C1. Therefore, as shown by a thin line in FIG. 1, the lever 434 is separated from the workpiece W on the right side. When the gap C <b> 1 is consumed, the flange portion 432 b comes into contact with the end plate 363. For this reason, the cylinder 432 and the lever 434 cannot move further to the right side.

  Subsequently, the control device further moves the central shaft 40 to the right side. As a result, the shaft 430 is inserted into the cylinder 432 that is stopped. At this time, the guide pin 431 moves the pin guide groove 432a by the groove length C2. Here, the pin guide groove 432a extends in an oblique direction. Therefore, as shown by the dotted lines in FIGS. 1 and 2, when the guide pin 431 moves in the pin guide groove 432a, the cylinder 432, that is, the lever 434 swings with respect to the shaft 430 by a predetermined angle θ. The lever 434 is retracted radially outside the outer edge of the workpiece W by the swinging. Thereafter, the operator removes the workpiece W from the head stock 2.

  When attaching the workpiece W to the head stock 2, first, the operator attaches the workpiece W to the jig 34. At this time, the two positioning pins 340 are inserted into the two recesses W1. Next, the control device moves the central shaft 40 to the left side. Then, the lever 434 is swung so that the tip of the lever 434 faces radially inward (from the dotted line state shown in FIG. 2 to the solid line state). Subsequently, the control device further moves the central shaft 40 to the left side. Then, the lever 434 is brought into contact with the workpiece W.

[Jig mounting method]
Next, a jig mounting method executed in the work contact unit of the present embodiment will be described. The jig is replaced at the time of setup change for changing the type of the workpiece W. For this reason, the jig mounting method described below is executed at the time of setup change.

  The jig mounting method includes a jig setting process and an alignment process. FIG. 4 is a schematic diagram of the workpiece contact unit of the present embodiment in the jig setting step of the jig mounting method. FIG. 5 shows a schematic diagram of the workpiece contact unit in the alignment step of the jig mounting method. 4 and 5 correspond to FIG.

  As shown in FIG. 4, in the jig setting step, the operator wraps the jig 34 around the collet tube portion 300. The collet side taper portion 300a and the regulation side taper portion 352 are separated from each other. For this reason, the collet cylinder part 300 can be expanded and contracted in the radial direction. Therefore, the operator can easily wrap the jig 34 around the collet tube portion 300.

  As shown in FIG. 5, in the alignment process, the operator first engages the hexagon wrench 90 with the recess 352a. Subsequently, the operator rotates the hexagon wrench 90, that is, the mandrel 35 around the axis. Here, the screw portion 350 a of the mandrel 35 is screwed with the screw portion 363 aa of the end plate 363. For this reason, when the mandrel 35 is rotated, the mandrel 35 is screwed to the left. At this time, the regulation-side taper portion 352 is in sliding contact with the collet-side taper portion 300a from the radially inner side. Therefore, the collet side taper portion 300a, that is, the collet tube portion 300 is expanded outward in the radial direction. The jig 34 can be aligned by expanding the diameter of the collet tube 300. That is, the collet tube part 300 and the jig 34 can be arranged coaxially. Through the above operation, the jig 34 is fixed to the jig receiving member 33 in the aligned state.

  When removing the jig 34 from the workpiece contact unit 3, first, the operator uses the hexagon wrench 90 to rotate the mandrel 35 in the reverse direction (the reverse direction to the alignment step shown in FIG. 5). Then, the collet tube portion 300 is deformed in a reduced diameter. Next, the operator removes the jig 34 from the collet tube part 300.

[Function and effect]
Next, the effects of the workpiece contact unit and the machine tool of this embodiment will be described. As shown in FIG. 5, the workpiece contact unit 3 of the present embodiment uses a collet member 30 to perform positioning (centering, alignment) and fixing with the reproducibility of the jig 34. For this reason, the alignment accuracy of the jig 34 is high. The jig 34 determines the position of the workpiece W during processing. For this reason, the processing accuracy of the workpiece W can be increased. In addition, the operator can perform the alignment operation, attachment operation, and removal operation of the jig 34 only by rotating the hexagon wrench 90. For this reason, the alignment operation | work of the jig | tool 34 and an exchange operation | work are easy. Moreover, the setup change work is easy. Moreover, as shown in FIG. 5, the collet member 30 of the workpiece contact unit 3 of the present embodiment aligns the jig 34 from the radially inner side. For this reason, it is easy to align the cylindrical or annular jig 34. In addition, even when the jig 34 is repeatedly attached and detached due to setup change or the like, the reproducibility of the mounting accuracy of the jig 34 can be ensured.

  Further, in the case of a jig that is positioned and attached / removed by uneven fitting (inlay), a gap is required in the fitting portion. For this reason, the centering man-hour increases. In addition, the alignment accuracy decreases. On the other hand, according to the workpiece contact unit 3 of the present embodiment, as shown in FIG. 3, no gap is required between the regulation-side taper portion 352 and the collet-side taper portion 300a. For this reason, the centering man-hour is reduced. In addition, alignment accuracy is improved.

<Second embodiment>
The difference between the workpiece contact unit and machine tool of the present embodiment and the workpiece contact unit and machine tool of the first embodiment is that a Keley jig is used as a jig, and a workpiece holding unit. This is the point that a tailstock is used. Here, only differences will be described.

  FIG. 6 shows a cross-sectional view in the left-right direction (main axis direction) of the headstock and the tailstock of the machine tool of the present embodiment. In addition, about the site | part corresponding to FIG. 1, it shows with the same code | symbol. As shown in FIG. 6, the headstock 2 includes a workpiece contact unit 3. The Keley jig 37 of the workpiece contact unit 3 includes three power transmission pins 370. The power transmission pin 370 is inserted into the recess W2 of the workpiece W. A rotational force is transmitted from the headstock 2 to the workpiece W via the power transmission pin 370. As the type of workpiece W to be processed is changed, the position of the contact surface of the workpiece W with respect to the kelay jig 37 is different and the position and number of the positioning recesses W2 are also different. Is done. The tailstock 5 is disposed on the right side of the headstock 2. The tailstock 5 includes a shaft 50. The shaft 50 can be separated from the workpiece W from the right side.

  The workpiece contact unit and the machine tool of the present embodiment and the workpiece contact unit and the machine tool of the first embodiment have the same operational effects with respect to the parts having the same configuration. According to the machine tool 1 of the present embodiment, the workpiece W can be clamped from both sides in the left-right direction by the kelay jig 37 and the core presser 5 during machining. Further, the workpiece W can be rotated by the kelay jig 37.

<Others>
The embodiment of the workpiece contact unit and the machine tool according to the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. Various modifications and improvements that can be made by those skilled in the art are also possible.

  The number of slits S (see FIG. 2) of the collet member 30 is not particularly limited. Moreover, the kind of collet member 30 is not specifically limited. For example, an outer diameter collet type collet member 30 that holds the jig 34 from the radially outer side may be used.

  The dimensions of the jig 34 and the kelay jig 37 are not particularly limited. When the collet member 30 is an inner diameter collet type, the jig 34 and the keley jig 37 may have an inner peripheral surface held by the collet member 30. Specifically, the jig 34 and the Keley jig 37 may have a recess, a hole, or the like. Further, when the collet member 30 is an outer diameter collet type, the jig 34 and the kelet jig 37 may have an outer peripheral surface held by the collet member 30. Specifically, the jig 34 and the kelay jig 37 may have a convex part, a boss part, or the like.

  Further, the replacement timing of the jig 34 and the kelay jig 37 may not correspond to the setup change. The screwing means of the mandrel 35 is not particularly limited. A driver or the like may be used. Further, the operator may directly screw the mandrel 35 by hand. Further, the mandrel 35 may not be screwed. The mandrel 35 may slide linearly in the left-right direction. The mandrel 35 may be moved automatically by the control device of the machine tool 1.

  The kind of the work holding unit 4 is not particularly limited. A collet chuck, a finger chuck, a ball lock chuck, a pin arbor chuck, a wedge-shaped three-jaw chuck, a magnetic chuck, and the like may be used. The main axis direction of the machine tool 1 may be the vertical direction. That is, the workpiece W may be placed on the upper surface of the jig 34. The kind of machine tool 1 is not specifically limited. A horizontal lathe, a front lathe, a vertical lathe, a milling machine, a drilling machine, a milling cell, etc. may be used.

1: Machine tool.
2: Headstock.
3: Workpiece contact unit, 30: Collet member, 300: Collet tube portion, 300a: Collet side taper portion, 301: Flange portion, 31: Cylinder guide member, 32: Mandrel guide member, 33: Jig receiving member , 34: jig, 340: positioning pin, 35: mandrel, 350: small diameter portion, 350a: screw portion, 351: large diameter portion, 352: restriction side taper portion, 352a: concave portion, 36: housing, 36a: workpiece Holding portion accommodating portion, 360: sleeve, 361: guide member for central shaft, 361a: guide hole, 362: case, 362a: guide hole, 363: end plate, 363a: mounting hole for mandrel, 363aa: screw portion, 363b : Cylinder insertion hole, 37: Kelay jig, 370: Power transmission pin.
4: Workpiece holding part, 40: Central shaft, 41: Stepped sleeve, 42: Branch member, 420: Branch part, 421: Sleeve mounting hole, 422: Shaft mounting hole, 43: Finger part, 430: Shaft, 431: Guide pins, 432: cylinder, 432a: pin guide groove, 432b: flange portion, 433: coil spring, 434: lever.
5: core presser, 50: shaft.
90: Hex wrench.
C1: gap, C2: groove length, S: slit, W: workpiece, W1: recess, W2: recess.

Claims (4)

A collet member deformable in the radial direction ;
Is located radially outwardly of said collet member, the positioning of the workpiece by said collet member is centering on the collet member coaxially by diameter expansion deformation Rutotomoni abuts the workpiece alignment state An annular jig to perform ,
Equipped with a,
The collet member, the jig, the workpiece contact unit you core tone from the radially inner side.   The workpiece contact unit according to claim 1, wherein the jig positions the workpiece only in the axial direction by contacting the workpiece from only the axial direction.   A machine tool comprising: the workpiece contact unit according to claim 1; and a workpiece holding unit that holds the workpiece.   The jig is a Keley jig that transmits a rotational force to the workpiece,
  The machine tool according to claim 3, wherein the work holding portion is a tailstock that is disposed on the opposite side of the work and sandwiches the work and is in contact with the work.

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