JP4728117B2 - Workpiece holding tube, machine tool, and workpiece machining method - Google Patents

Description

  The present invention relates to a workpiece holding tube, a machine tool, and a workpiece machining method.

  Conventionally, when processing a bar (bar material) with a machine tool such as a lathe, as shown in Patent Document 1, for example, an automatic bar feeder separate from the machine tool may be used.

  An example of a method for supplying a bar to a machine tool by an automatic bar feeder will be described with reference to FIG. The automatic bar feeder includes a push bar 101 and grips a workpiece (bar) W with a finger 101 a provided at a front end portion of the push bar 101. The workpiece W passes through the main shaft 111 of the machine tool 110 and is sent in the axial direction of the main shaft so as to be guided by the guide portion 112a of the collet chuck 112 provided at the front end portion of the main shaft 111. Thereby, the workpiece W is mounted on the machine tool 110.

Then, the workpiece W is machined while being fed to the machining blade 113 side through the guide portion 114a of the guide bush 114 provided on the machining blade 113 side from the collet chuck 112.
Japanese Patent Laid-Open No. 9-070702

  However, when the workpiece W has a very small diameter and is long, the distance between the guide portion 112a of the collet chuck 112 and the guide portion 114a of the guide bush 114 is increased in the workpiece W machining method and the machine tool 110 shown in FIG. For this reason, when the workpiece W is fed from the collet chuck 112 to the guide portion 114a of the guide bush 114, the vicinity of the tip of the workpiece W is bent, and the guide portion 114a of the guide bush 114 may not be able to guide well. It was.

  In addition, when a long workpiece W having a very small diameter is gripped by the finger 101a of the push rod 101 and guided to the guide portion 112a of the collet chuck 112, the vicinity of the tip of the workpiece W is bent by its own weight. Since there is a difference in diameter with the chuck 112, an error occurs in the position of the center axis of the workpiece W. Therefore, the workpiece W cannot be guided to the guide portion 112a of the collet chuck 112, and the workpiece W is automatically replaced with the machine tool 110. There was a case that could not be done.

  The present invention has been made in view of the above circumstances, and provides a workpiece holding tube, a machine tool, and a workpiece machining method that reduce workpiece deflection and facilitate process operations such as workpiece feeding and automatic replacement. With the goal.

In order to achieve the above object, a work holding tube according to the first aspect of the present invention is
A workpiece holding tube gripped by the collet chuck on a spindle of a machine tool having a collet chuck that grips a workpiece of a predetermined diameter,
A tube having a hollow portion into which a small-diameter workpiece having a smaller diameter than the predetermined diameter is inserted;
A finger chuck attached to one end of the tube and having a diameter reduced by being gripped by the collet chuck and gripping a part of the small-diameter workpiece ;
A bush disposed in the hollow portion of the tube and supporting another part of the small-diameter workpiece;
A pipe supported by the bush in the hollow portion of the tube;
Equipped with a,
The bush supports the small-diameter workpiece through the pipe .

  In order to achieve the above object, a work holding tube according to a second aspect of the present invention is:
  A workpiece holding pipe that is supplied to a spindle of a machine tool including a collet chuck that has a circular inner peripheral cross section and grips a workpiece having a predetermined diameter, and is gripped by the collet chuck.
  A tube having a hollow portion into which a small-diameter workpiece having a smaller diameter than the predetermined diameter and a deformed material is inserted;
  By having a circular outer peripheral section, an inner peripheral section corresponding to the shape of the small-diameter workpiece so that the small-diameter workpiece can be supported, and being attached to one end of the tube and being gripped by the collet chuck And a finger chuck for reducing the diameter and gripping a part of the small-diameter workpiece.

In order to achieve the above object, a machine tool according to a third aspect of the present invention provides:
A spindle to which a workpiece of a predetermined diameter is supplied;
A collet chuck capable of gripping the supplied workpiece;
A machine tool comprising the work bush and a guide bush capable of holding a tip portion of a work having a smaller diameter than the predetermined diameter,
The small-diameter work is inserted into a tube having a hollow portion, and is gripped by a finger chuck attached to one end of the tube and supplied to the main shaft,
The collet chuck, the fingers chuck is gripped thereby diameter and Ri graspable der the small-diameter work via the front Symbol finger chuck,
The finger chuck is gripped by the collet chuck in a state in which a part protrudes from the collet chuck toward the guide bush. It is characterized by being close to .

In order to achieve the above object, a machine tool according to the fourth aspect of the present invention provides:
A spindle to which a workpiece of a predetermined diameter is supplied;
A collet chuck capable of gripping the supplied workpiece;
A machine tool comprising the work bush and a guide bush capable of holding a tip portion of a work having a smaller diameter than the predetermined diameter,
The small-diameter work is inserted into a tube having a hollow portion, and is gripped by a finger chuck attached to one end of the tube and supplied to the main shaft,
The collet chuck can grip the small-diameter workpiece via the finger chuck by gripping and reducing the diameter of the finger chuck,
A bush that supports the small-diameter workpiece is disposed in the hollow portion of the tube ,
The hollow portion of the tube further comprises a pipe supported by the bush,
The bush is characterized in that for supporting the small diameter work via the front Symbol pipe.

  In order to achieve the above object, a machine tool according to a fifth aspect of the present invention provides:
  A spindle to which a workpiece of a predetermined diameter is supplied;
  A collet chuck having a circular inner circumferential section capable of gripping the supplied workpiece;
  A machine tool comprising the workpiece and a guide bush capable of holding a tip portion of a workpiece having a smaller diameter than the predetermined diameter and having a deformed shape,
  The small-diameter workpiece is inserted into a tube having a hollow portion, and is attached to one end of the tube and has a circular outer peripheral cross section, and has a shape corresponding to the shape of the small-diameter workpiece so as to support the small-diameter workpiece. Gripped by a finger chuck having a circumferential section and supplied to the spindle,
  The collet chuck can grip the small-diameter workpiece via the finger chuck by gripping the finger chuck and reducing the diameter.

In order to achieve the above object, a workpiece machining method according to a sixth aspect of the present invention includes:
A small-diameter workpiece, which is a deformed material, is inserted into a tube, has a circular outer circumferential section attached to one end of the tube, and has an inner circumferential section corresponding to the shape of the small-diameter workpiece so as to support the small-diameter workpiece Gripping the small-diameter workpiece on a finger chuck;
A step of feeding the small-diameter workpiece to a spindle of a machine tool;
A step of grasping a collet chuck having an inner peripheral section of the circular small diameter workpieces fed to the main shaft, through the finger chuck,
Holding the tip portion of the small-diameter workpiece with a guide bush;
Releasing the gripping of the small-diameter workpiece by the collet chuck, and sending the small-diameter workpiece to the cutting tool side by the amount of machining;
Gripping the small-diameter workpiece again by the collet chuck;
And a step of cutting the small-diameter workpiece with the cutting tool.

  According to the present invention, it is possible to provide a workpiece holding tube, a machine tool, and a workpiece machining method that reduce the deflection of the workpiece and facilitate process operations such as workpiece feeding and automatic replacement.

[Embodiment 1]
A machine tool and a workpiece holding pipe according to an embodiment of the present invention will be described below with reference to the drawings. The machine tool 1 is a bar material (bar material) having a very small diameter (for example, a diameter of about 0.2 mm to 1.0 mm) and a long length (1 to 2 m), and is an automatic machine for processing the workpiece W stored in the workpiece holding tube 2. It is a lathe.

  As shown in FIG. 2, the workpiece W is stored in the workpiece holding tube 2. The workpiece holding tube 2 is a tube for supplying the workpiece W to the spindle 11 of the machine tool 1, and the workpiece W is reduced in order to reduce or prevent the deflection of the workpiece W when the workpiece W is automatically replaced or fed out. Is a tube that holds

  The work holding tube 2 includes a tube 21 and a finger chuck 22. The tube 21 is a hollow tube that accommodates the workpiece W. A plurality of bushes 21 a are inserted into the inner wall surface of the tube 21 at intervals. Since the bush 21 a supports the workpiece W in the hollow portion of the tube 21, the volume of the hollow portion of the tube 21 can be increased to reduce the weight of the tube 21. The bush 21a may be adhered to the inner wall surface of the tube 21, bolted, or a spring may be disposed between the bushes 21a and fixed by the biasing force of the spring.

  The finger chuck 22 grips the workpiece W. As shown in FIG. 2, the finger chuck 22 has a claw 22 a divided into three parts and a convex part 22 b formed at one end. The finger chuck 22 holds and holds the workpiece W by the three-part claw 22a. Further, the finger chuck 22 is attached to the tube 21 by screwing or inserting the convex portion 22 b at the rear end into the hollow portion of the tube 21.

  As shown in FIGS. 1 and 3, the machine tool 1 includes a base 10 and a headstock 12 that supports the spindle 11 that is supported by the base 10 and that is driven to rotate by a spindle rotation motor M. The headstock 12 is movably driven by a drive motor 14 via a ball screw 13 as shown in FIG.

  The main shaft 11 is rotatably supported by a plurality of bearings 16 fixed to a bearing support 15 such as a bearing case. The bearing 16 is fixed in the axial direction by a bearing nut 17.

  A push tube 30 is disposed in the hollow portion 11 a of the main shaft 11, and the work holding tube 2 is inserted into the hollow portion 30 a of the push tube 30. A collet chuck 18 is disposed on the front end portion of the main shaft 11 via a collet sleeve 19. The front end of the push tube 30 is in contact with the rear end of the collet sleeve 19.

  The collet chuck 18 chucks (grips) the workpiece W via the finger chuck 22 of the workpiece holding tube 2. The collet chuck 18 is formed with a guide hole 18a into which the finger chuck 22 is inserted and a tapered portion 18b. The collet chuck 18 is held in a collet sleeve 19 fixed to a hollow portion of the front end portion of the main shaft 11 so as to be movable in the axial direction while receiving a biasing force of the coil spring 31 toward the front end of the main shaft 11. The collet chuck 18 can be opened and closed, and by opening the collet chuck 18, the insertion state of the finger chuck 22 can be loosened. By screwing the cap nut 32 into the front end portion of the main shaft 11, the cap nut 32 is brought into contact with the tapered portion 18 b of the collet chuck 18 to regulate the position of the collet chuck 18 in the axial direction. A stopper ring 34 is fitted and fixed to the rear end portion of the hollow portion 18 c of the collet chuck 18 by a pin 33. The stopper ring 34 regulates the position of the workpiece holding tube 2 in the axial direction by contacting the front end of the tube 21 when the finger chuck 22 is gripped by the collet chuck 18.

  A flange 36 is disposed in front of the base 10, and a guide bush 35 is held by a holder 37 fixed in front of the flange 36. The guide bush 35 holds the tip portion of the work W stored in the work holding tube 2. The guide bush 35 is formed with a guide hole 35a for guiding and holding the workpiece W. The guide bush 35 is formed with a short axial length.

  The guide bush 35 is disposed immediately in front of the collet chuck 18 and is disposed so that the distance between the guide bush 35 and the collet chuck 18 is shortened. Therefore, the finger chuck 22 gripped by the collet chuck 18 and the collet chuck 18 are arranged close to each other so that the workpiece W does not bend. The guide bush 35 is held and fixed in the guide bush holding hole 37 a of the holder 37.

  Moreover, the machine tool 1 is provided with a tool post (not shown) having a cutting tool 40 that is movably driven.

  Here, a method for machining the workpiece W in the machine tool 1 will be described. First, the workpiece W is inserted into the hollow portion of the tube 21 of the workpiece holding tube 2 and supported by the bush 21a, and is held and held by the claw 22a of the finger chuck 22.

  The workpiece holding tube 2 holding the workpiece W is mounted on the machine tool 1 by an automatic bar feeder (not shown). Specifically, the workpiece holding tube 2 is inserted into the hollow portion 30 a of the push tube 30 disposed in the hollow portion 11 a of the main shaft 11, and the finger chuck 22 of the workpiece holding tube 2 is inserted into the guide hole 18 a of the collet chuck 18. The finger chuck 22 of the work holding tube 2 is gripped by the collet chuck 18 by being inserted. Thereafter, the tip end portion of the workpiece W is held in the guide hole 35 a of the guide bush 35. Thereby, the workpiece holding tube 2 is mounted on the machine tool 1.

  Next, by opening the collet chuck 18, the insertion state of the work W of the finger chuck 22 is loosened. As shown in FIG. 4, the tip of the workpiece W is gripped by a collet chuck 51 provided in the workpiece pulling device 50, and the workpiece pulling device 50 is moved to the right in the axial direction of the workpiece W in FIG. The workpiece W is sent out by the length of the workpiece W. Thereafter, the collet chuck 18 is closed. The collet chuck 51 of the workpiece extraction device 50 is opened to release the workpiece W, and the workpiece extraction device 50 is retracted. The workpiece pulling device 50 may be a counter spindle stock.

  As another method for feeding the workpiece W, first, the tip portion of the workpiece W is gripped by the collet chuck 51 of the workpiece drawing device 50. By opening the collet chuck 18 without moving the workpiece drawing device 50, the inserted state of the workpiece W is loosened. The spindle 11 is moved to the left in FIG. 4 by the length of the workpiece W to be machined. Thereafter, the collet chuck 18 is closed. The collet chuck 51 of the workpiece extraction device 50 is opened to release the workpiece W, and the workpiece extraction device 50 is retracted. In this way, the workpiece W may be sent out.

  Then, the workpiece W is machined by the cutting tool 40, and when this machining is completed, the workpiece is similarly fed again by the workpiece drawing device 50, and machining of the workpiece W is repeated to process a plurality of parts from the workpiece W. .

  When the processing of one workpiece W is completed, the workpiece holding tube 2 is taken out from the machine tool 1 by an automatic bar feeder, and another workpiece holding tube 2 is mounted on the machine tool 1 again to remove the workpiece holding tube 2. Replacement is performed.

  As described above, in the work holding tube 2 of the present embodiment, the work W is inserted into the tube 21 and supported by the bush 21a, and is held by being held by the claws 22a of the finger chuck 22. Deflection can be reduced or prevented.

  Further, in the machine tool and the workpiece machining method of the present embodiment, the workpiece W is supplied while being held in the workpiece holding pipe 2, and the finger chuck 18 and the guide bush 35 having a short axial length are provided. Are arranged close to each other, the bending of the workpiece W is reduced or prevented, and process operations such as feeding out the workpiece W and automatic replacement can be easily performed.

[Embodiment 2]
A machine tool and a work holding tube according to Embodiment 2 of the present invention are shown in FIGS. Hereinafter, only differences from the first embodiment will be described. In principle, other configurations are the same as those of the first embodiment, and therefore, the same reference numerals are given in the drawings and description thereof will be omitted.

  As shown in FIG. 6, the work holding tube 62 includes a tube 621 and a finger chuck 622. Unlike the tube 21 of the first embodiment, the tube 621 is not provided with a bush in the hollow portion. The tube 621 is shorter in the axial direction than the tube 21 of the first embodiment, and the finger chuck 622 is longer in the axial direction than the finger chuck 22 of the first embodiment. Similar to the first embodiment, the finger chuck 622 is formed with a three-part claw 622a and a convex portion 622b that is screwed or inserted into the hollow portion of the tube 621 at the rear end.

  Since the finger chuck 622 of the work holding tube 62 is relatively long in the axial direction, it is gripped by the collet chuck 18 and supported by the guide bush 63. The guide bush 63 is disposed in the hollow portion 18 c of the collet chuck 18. A flange portion 63 a is formed at the rear end of the guide bush 63. The flange 63a abuts on the rear end of the collet chuck 18 and receives a biasing force in the front end direction of the main shaft 11 by the coil spring 31, whereby the guide bush 63 is held so as to be movable in the axial direction together with the collet chuck 18. .

  The front end of the tube 621 of the work holding tube 62 is in contact with the rear end of the collet sleeve 19 so that the position in the axial direction is regulated. Therefore, the stopper ring 34 of the first embodiment is not provided in the second embodiment.

  The guide bush 65 is formed with a guide hole 65a for guiding and holding the workpiece W and a hollow portion 65b into which the finger chuck 622 is inserted. The guide bush 65 is held by a sleeve 67 held by a sleeve chuck 66 instead of the holder 37 of the first embodiment.

  Also in the present embodiment, similarly to the first embodiment, it is possible to reduce or prevent the bending of the workpiece W, and it is possible to easily perform processes such as feeding the workpiece W and automatic replacement.

  The present invention has been described with reference to the embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made. For example, in each of the embodiments, the example of processing the workpiece W that is a bar material having an extremely small diameter has been described. However, in the present invention, a workpiece such as a deformed material or a flat plate can be processed as shown in FIG. It is. FIG. 8A shows an example in which a workpiece W having a rectangular cross-sectional shape is held by the workpiece holding tube 2 (62). 8B is a workpiece W having a square cross-sectional shape, FIG. 8C is a workpiece W having a hexagonal cross-sectional shape, and FIG. 8D is a workpiece W having a triangular cross-sectional shape. 8 (E) is a workpiece W having a curved surface at the center of a long piece having a rectangular cross-sectional shape, and FIG. 8 (F) is a rectangular shape in which a part of the circular cross-sectional shape is open and continuous with the circular shape. An example in which the workpieces W are respectively held by the workpiece holding pipe 2 (62) is shown. In this way, by holding the workpiece W such as a deformed material or a flat plate on the workpiece holding pipe 2 (62), it can be handled like a round material, and can be easily mounted on a machine tool by an automatic bar feeder. be able to.

  Further, in each of the above embodiments, the example of the finger chucks 22 and 622 having the three claws 22a and 622a has been described. However, the finger chucks 22 and 622 are not necessarily divided into three, and are divided into four or more. Alternatively, it may be divided in two.

In each of the above-described embodiments, the guide bushes 35 and 65 are stationary. However, a rotating guide bush that rotates in synchronization with the main shaft 11 may be used.
In particular, when a workpiece W such as a deformed material or a flat plate as shown in FIG. 8 is held by the workpiece holding tube 2 (62) and processed, a rotating guide bush is used.

  In the first embodiment, the example in which the workpiece W is directly supported by the bush 21a in the hollow portion of the tube 21 of the workpiece holding tube 2 has been described. However, as shown in FIG. The pipe 23 may be supported by the bush 21a so that the workpiece W is not bent. Thus, by supporting the workpiece W in the workpiece holding pipe 2 via the pipe 23, the number of bushes 21a can be reduced. As a result, the structure and manufacture of the work holding tube 2 can be simplified, and the assembly work can be facilitated.

It is a partial sectional view showing composition of a machine tool and a work maintenance pipe concerning Embodiment 1 of the present invention. (A) is a partially omitted sectional view showing the entire configuration of the workpiece holding tube shown in FIG. 1, and (B) is a front view of the workpiece holding tube. It is sectional drawing showing the whole structure of the machine tool shown in FIG. 1, and a workpiece | work holding pipe. It is explanatory drawing for demonstrating the process of extracting a workpiece | work with a workpiece | work extraction apparatus. It is a partial sectional view showing composition of a machine tool and a work maintenance pipe concerning Embodiment 2 of the present invention. (A) is a partially omitted sectional view showing the entire configuration of the workpiece holding tube shown in FIG. 5, and (B) is a front view of the workpiece holding tube. It is sectional drawing showing the whole machine tool shown in FIG. 5, and the whole structure of a workpiece | work holding pipe. (A)-(F) is a front view showing the workpiece | work which has various cross-sectional shapes hold | maintained at the workpiece | work holding tube. (A) is a partially omitted cross-sectional view showing an overall configuration of a modified example of the workpiece holding tube shown in FIG. 2, and (B) is a front view of the workpiece holding tube shown in (A). It is a partial cross section showing the structure of the conventional machine tool.

Explanation of symbols

1,60 Machine tool W Work piece 11 Spindle 18 Collet chuck 2, 62 Work holding tube 21, 621 Tube 21a Bushing 22, 622 Finger chuck 35, 65 Guide bush 40 Cutting tool

Claims (6)

A workpiece holding tube gripped by the collet chuck on a spindle of a machine tool having a collet chuck that grips a workpiece of a predetermined diameter,
A tube having a hollow portion into which a small-diameter workpiece having a smaller diameter than the predetermined diameter is inserted;
A finger chuck attached to one end of the tube and having a diameter reduced by being gripped by the collet chuck and gripping a part of the small-diameter workpiece ;
A bush disposed in the hollow portion of the tube and supporting another part of the small-diameter workpiece;
A pipe supported by the bush in the hollow portion of the tube;
Equipped with a,
The bush supports the small-diameter workpiece through the pipe.
A workpiece holding tube characterized by that.   A workpiece holding pipe that is supplied to a spindle of a machine tool including a collet chuck that has a circular inner peripheral cross section and grips a workpiece having a predetermined diameter, and is gripped by the collet chuck.
  A tube having a hollow portion into which a small-diameter workpiece having a smaller diameter than the predetermined diameter and a deformed material is inserted;
  By having a circular outer peripheral section, an inner peripheral section corresponding to the shape of the small-diameter workpiece so that the small-diameter workpiece can be supported, and being attached to one end of the tube and being gripped by the collet chuck A finger chuck that reduces the diameter and grips a part of the small-diameter workpiece;
  A workpiece holding tube characterized by that. A spindle to which a workpiece of a predetermined diameter is supplied;
A collet chuck capable of gripping the supplied workpiece;
A machine tool comprising the work bush and a guide bush capable of holding a tip portion of a work having a smaller diameter than the predetermined diameter,
The small-diameter work is inserted into a tube having a hollow portion, and is gripped by a finger chuck attached to one end of the tube and supplied to the main shaft,
The collet chuck, the fingers chuck is gripped thereby diameter and Ri graspable der the small-diameter work via the front Symbol finger chuck,
The finger chuck is gripped by the collet chuck in a state in which a part protrudes from the collet chuck toward the guide bush. Close to the
A machine tool characterized by that. A spindle to which a workpiece of a predetermined diameter is supplied;
A collet chuck capable of gripping the supplied workpiece;
A machine tool comprising the work bush and a guide bush capable of holding a tip portion of a work having a smaller diameter than the predetermined diameter,
The small-diameter work is inserted into a tube having a hollow portion, and is gripped by a finger chuck attached to one end of the tube and supplied to the main shaft,
The collet chuck can grip the small-diameter workpiece via the finger chuck by gripping and reducing the diameter of the finger chuck,
A bush that supports the small-diameter workpiece is disposed in the hollow portion of the tube,
The hollow portion of the tube further comprises a pipe supported by the bush,
The bush supports the small-diameter workpiece through the pipe.
A machine tool characterized by that.   A spindle to which a workpiece of a predetermined diameter is supplied;
  A collet chuck having a circular inner circumferential section capable of gripping the supplied workpiece;
  A machine tool comprising the workpiece and a guide bush capable of holding a tip portion of a workpiece having a smaller diameter than the predetermined diameter and having a deformed shape,
  The small-diameter workpiece is inserted into a tube having a hollow portion, and is attached to one end of the tube and has a circular outer peripheral cross section. Gripped by a finger chuck having a circumferential section and supplied to the spindle,
  The collet chuck can grip the small-diameter workpiece via the finger chuck by gripping and reducing the diameter of the finger chuck.
  A machine tool characterized by that. A small-diameter workpiece, which is a deformed material, is inserted into a tube, has a circular outer circumferential section attached to one end of the tube, and has an inner circumferential section corresponding to the shape of the small-diameter workpiece so that the small-diameter workpiece can be supported. Gripping the small-diameter workpiece on a finger chuck;
A step of feeding the small-diameter workpiece to a spindle of a machine tool;
A step of grasping a collet chuck having an inner peripheral section of the circular small diameter workpieces fed to the main shaft, through the finger chuck,
Holding the tip portion of the small-diameter workpiece with a guide bush;
Releasing the gripping of the small-diameter workpiece by the collet chuck, and sending the small-diameter workpiece to the cutting tool side by the amount of machining;
Gripping the small-diameter workpiece again by the collet chuck;
Cutting the small-diameter workpiece with the cutting tool ,
A workpiece machining method characterized by the above.

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