JP2011167773A - Chuck device and lathe equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chuck device with a diaphragm in a simple and compact configuration and also having mounting compatibility with a collet chuck device, and to provide a lathe equipped with the same. <P>SOLUTION: A male screw is arranged at a tip of a spindle 21 of an automatic lathe 1 and a holding member 51 is screwed thereto. The circumferential edge of the diaphragm 52 is fastened to the holding member 51 with a bolt and a chuck force adjusting screw 58 is screwed to the center part of the diaphragm 52. The chuck force adjusting screw 58 is movable in an axial direction by the screw structure of the chuck force adjusting screw 58. When a corner 43b of a toggle 43 of a toggle switch part 111 does not press a push pipe 41, a gap is formed between the chuck force adjusting screw 58 and a chuck opening/closing rod 55. Thereby, the diaphragm 52 is restored from elastic deformation by membrane force and a chuck claw 53 mounted on the diaphragm 52 holds a workpiece. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a chuck device and a lathe equipped with the chuck device.

  In a machine tool such as a lathe, a structure in which a main shaft grips a workpiece (hereinafter referred to as a gripping mechanism) includes a toggle and a collet chuck device as disclosed in Patent Documents 1 and 2, for example. Yes.

  A gripping mechanism using a collet chuck device is widely used because it has an advantage that it can be used at a relatively low cost. On the other hand, in such a gripping mechanism, it is difficult to increase the repeatability of the swing of the workpiece after gripping when the workpiece is gripped, for example, because the collet chuck has a slit.

  As a gripping mechanism for improving the drawbacks of the collet chuck device as described above, a configuration including a diaphragm chuck device that grips a workpiece by a film force of a diaphragm driven by air is known (for example, Patent Document 3).

Japanese Patent Laid-Open No. 4-115804 JP-A-2-232104 JP 2002-321108 A

  A lathe that uses a collet chuck device includes a gripping mechanism that is driven by toggle as described above, but does not have an air supply mechanism that operates the diaphragm chuck device. In order to open the chuck, the diaphragm chuck device disclosed in Patent Document 3 requires an air supply mechanism in order to open the chuck claw by feeding air into the diaphragm and inflating the diaphragm into a convex shape. Therefore, the spindle had to be dedicated. In order to attach an air diaphragm chuck device as disclosed in Patent Document 3 to the main shaft, the main shaft end must be large. Therefore, when the diaphragm chuck device is to be attached to the lathe, the spindle and the air supply mechanism have to be dedicated.

  That is, in a collet chuck device and the diaphragm chuck device, the main shaft, and headstock shared since the structure is different in the air supply mechanism or the like for driving the gripping mechanism is difficult, when purchasing an automatic lathe, which previously Only one side could be used after deciding whether to make it. Therefore, when the collet chuck device and the diaphragm chuck device are used depending on the workpiece, they have to be processed by lathes of different gripping mechanisms, resulting in a problem of high cost.

  The present invention has been made in view of the above-described problems, and provides a chuck device that can be simply and compactly configured with a diaphragm and that is compatible with a collet chuck device, and a lathe equipped with the chuck device. For the purpose.

In order to achieve the above object, a chuck device according to a first aspect of the present invention includes:
A holding member disposed so as to be screwed to the tip of the rotating shaft;
A diaphragm that is held by the holding member and elastically deforms by receiving a predetermined pressing force in the axial direction of the rotating shaft;
A gripping member provided on the surface of the diaphragm, and comprising a plurality of claws for gripping a gripping object;
A pressing member that is disposed so as to be inserted through the rotating shaft in the axial direction, and that applies the pressing force toward the gripping object with respect to the diaphragm;
A spring member that biases a predetermined spring force in a direction opposite to the pressing direction with respect to the pressing member,
It is characterized by that.

In the above chuck device,
A toggle that is pivotably supported; and a pressing mechanism that urges the pressing member in the pressing direction by the toggle.
It is good as well.

The diaphragm further includes an adjusting screw that is screwed into a central portion of the diaphragm,
The adjustment screw includes a pressure receiving surface that comes into contact with the pressing member, and is capable of adjusting an interval between the pressure receiving surface and the pressing member.
It is good as well.

An intermediate member that is disposed between the adjustment screw and the spring member and transmits a reaction of the spring force to the diaphragm via the adjustment screw;
It is good as well.

The adjustment screw includes a recess into which a tip portion of the pressing member is inserted on a surface facing the pressing member.
It is good as well.

The pressing member and the adjustment screw are both hollow in the axial direction.
It is good as well.

The diaphragm includes a recess into which a front end portion of the pressing member is inserted on a surface facing the pressing member.
It is good as well.

The spring member is disposed between the pressing member and the holding member.
It is good as well.

The pressing member and the diaphragm are both hollow in the axial direction.
It is good as well.

The pressing member is divided into a plurality in the axial direction.
It is good as well.

In order to achieve the above object, a lathe according to the second aspect of the present invention provides:
A headstock,
A spindle rotatably supported on the spindle stock;
The chuck device provided on the main shaft, and
It is characterized by that.

In order to achieve the above object, another lathe of the present invention provides:
A headstock,
A spindle rotatably supported on the spindle stock;
A back spindle stock arranged opposite to the spindle stock;
A back spindle rotatably supported on the back spindle stock;
Provided with one or both of the main shaft and the back main shaft, and the chuck device described above.
It is characterized by that.

In the above lathe,
A collet chuck having a tapered surface formed on the outer peripheral portion and gripping a gripping object;
A collet chuck device comprising: a collet sleeve that is fitted to the tapered surface of the collet chuck to close the collet chuck by receiving the pressing force from the pressing member;
The collet chuck device and the chuck device including the diaphragm have mounting compatibility.
It is good as well.

  According to the configuration of the present invention, since a mechanism for supplying an air to the diaphragm is unnecessary while providing the diaphragm, a chuck device having a simple and compact configuration can be obtained. Further, by using such a chuck device, it is possible to change to a collet chuck device by exchanging only the chuck portion, so that it is possible to obtain a lathe that is compatible with the mounting of the diaphragm chuck device and the collet chuck device. it can.

It is sectional drawing which shows the structure of the automatic lathe which concerns on 1st Embodiment of this invention. It is a fragmentary sectional view showing a diaphragm chuck part. (A) is the figure which looked at the diaphragm and the chuck | zipper force adjustment screw from the axial direction, (b) is sectional drawing cut | disconnected by the III-III line | wire of (a). It is sectional drawing which shows the closing operation | movement of the chuck | zipper in 1st Embodiment. It is sectional drawing which shows the opening operation | movement of the chuck | zipper in 1st Embodiment. It is a fragmentary sectional view showing the modification which attached the collet chuck. It is a fragmentary sectional view showing composition of an automatic lathe concerning a 2nd embodiment of the present invention, and closing operation of a chuck. It is a fragmentary sectional view showing opening operation of a chuck in a 2nd embodiment. It is sectional drawing which shows the structure of the automatic lathe which concerns on 3rd Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. Hereinafter, an automatic lathe will be described as an example of a lathe. Unless otherwise specified in the description of the following positions, “front (side)” refers to the side on which the workpiece is mounted in the axial direction of the lathe spindle (or back spindle), and “rear (side)” It refers to the opposite side, and “axial direction” refers to the axial direction of the main axis (or back main axis).

(First embodiment)
1 to 3 show the configuration of the automatic lathe 1 according to the first embodiment. On the bed 16, a headstock 11 composed of a plurality of members is installed. The main shaft 21 is disposed so as to pass through the main shaft 11 and is rotatably supported by a bearing 22 and a bearing 23. The main shaft 21 is rotationally driven by a built-in motor 31. In the built-in motor 31, the stator 32 is disposed on the inner periphery of the headstock 11, and the rotor 33 is disposed on the outer periphery of the main shaft 21.

  The main shaft 21 is configured to be hollow, and a push tube 41 and a chuck opening / closing rod 55 are arranged in that hollow portion in order from the side opposite to the workpiece W. The chuck opening / closing rod 55 has a hollow structure, and the outer diameter and inner diameter of the chuck opening / closing rod 55 are formed such that the workpiece W side becomes smaller at a plurality of steps. The push tube 41 also has a hollow structure, and the end surface on the workpiece W side is in contact with one end surface of the chuck opening / closing rod 55. A plurality of grooves corresponding to a toggle 43 described later are provided on the outer peripheral surface of the push tube 41 in the vicinity of the end opposite to the workpiece W.

  The main shaft 21 extends to the rear of the main shaft base 11, and a toggle switching unit 111 is provided at the rear end portion of the main shaft 21. The toggle switching unit 111 includes a chuck opening adjustment nut 42, a toggle 43, a toggle support 44, a toggle sleeve 45, and a bearing 46.

  The chuck opening amount adjusting nut 42 is screwed with a threaded portion provided at the rear end portion of the main shaft 21, and moves the position of the toggle support 44 in the axial direction when rotated by a predetermined tool or the like.

  The toggle 43 is composed of a plurality of odd-shaped pieces. Each member of the toggle 43 has a fulcrum 43a, which is one end portion, supported by a toggle support 44. In the two shown, the range is restricted from other members by a rotation operation around the X axis in the figure. It can swing inside. Each member of the toggle 43 includes a corner portion 43b for pushing the push tube 41 in the workpiece W direction.

  The toggle sleeve 45 is formed in a substantially cylindrical shape, but a tapered surface is formed on the inner diameter side of the rear end portion, and the other end portion of the toggle 43 is in contact with the tapered surface and the inner peripheral surface. It has become. In addition, a bearing 46 is disposed on the outer peripheral surface of the toggle sleeve 45 (for simplification of illustration, illustration of a support member of the bearing 46 is omitted). As a result, when the main shaft 21 rotates, not only the chuck opening amount adjusting nut 42 screwed into the main shaft 21 but also the toggle 43, the toggle support 44 and the toggle sleeve 45 rotate together.

  In order to drive such a toggle switching unit 111, the automatic lathe 1 includes a cylinder 12, a cylinder rod 13, and an arm 14. The cylinder 12 receives the supply of air from the intake port 17 or the intake port 18 to expand and contract the cylinder rod 13, thereby rotating the arm 14 around a fulcrum 14 a within a predetermined range. The arm 14 is mechanically connected to a toggle sleeve 45, and is configured to be able to drive the toggle sleeve 45 back and forth in the axial direction in accordance with its rotational movement.

  Further, a diaphragm chuck portion 101 is provided on the workpiece W side of the automatic lathe 1. The diaphragm chuck unit 101 includes a holding member 51, a diaphragm 52, a chuck force adjustment screw 58, a chuck claw 53, a chuck force adjustment spring 56, and a chuck force adjustment spring receiver 57 in addition to the chuck opening / closing rod 55 described above. And.

  The holding member 51 is screwed into the front end portion of the main shaft 21. The holding member 51 holds the diaphragm 52 on the front end surface having, for example, six screw holes. Although the holding member 51 is substantially cylindrical, the inner diameter of a part of the inner periphery is smaller than the others, and the outer peripheral surface of the chuck force adjusting spring receiver 57 is held by the inner peripheral surface of this part.

  The diaphragm 52 is a member having a plate-like portion that undergoes predetermined elastic deformation (film deformation) with respect to an external force, and is fastened to the holding member 51 with bolts at, for example, six attachment holes 52a. The diaphragm 52 includes, for example, six screw holes 52c for holding the chuck claws 53 on the front end face. Further, a screw hole is further provided at the center of the diaphragm 52, and a chucking force adjusting screw 58 is screwed into the screw hole.

  The chucking force adjusting screw 58 is a hollow male screw. The chucking force adjusting screw 58 includes a hexagonal hole 58a provided on the front side and a recess 58b provided on the rear side. As shown in FIG. 1, the tip of the chuck opening / closing rod 55 is inserted into the recess 58b.

  The chuck claw 53 includes, for example, six claws that are split in the axial direction, and each claw is radially attached to the diaphragm 52 with bolts when viewed from the axial direction. As shown in FIG. 1, the chuck claw 53 can chuck the workpiece W on its inner diameter side surface.

  The chuck force adjusting spring 56 is a coil spring that is disposed between the chuck opening / closing rod 55 and the chuck force adjusting spring receiver 57 and has a predetermined spring force (repulsive force).

  The chuck force adjustment spring receiver 57 is a deformed hollow member, and is disposed between the chuck force adjustment screw 58 and the chuck force adjustment spring 56. The chuck force adjustment spring receiver 57 holds the chuck force adjustment spring 56 with the chuck opening / closing rod 55 and transmits the reaction of the spring force of the chuck force adjustment spring 56 to the chuck force adjustment screw 58.

  As described above, all of the members (the push tube 41, the chuck opening / closing rod 55, the chuck force adjusting screw 58, etc.) passing through the main shaft 21 and the central axis of the automatic lathe 1 can pass a rod-shaped material (work). It has a hollow structure.

  The automatic lathe 1 includes a control unit 100 that controls the overall operation of the automatic lathe 1 such as a chucking operation. The control unit 100 includes, for example, a CPU (Central Processing Unit), a RAM (Rondom Access Memory), a ROM (Read Only Memory), and the like.

  Next, the operation of the automatic lathe 1 according to this embodiment will be described. In addition, the operation | movement in each following embodiment is performed according to the instruction | indication of the control part 100 unless there is particular notice.

(When closing the chuck)
First, as shown in FIG. 4, air is sent to the intake port 18 of the cylinder 12 (arrow A1). Thereby, the cylinder 12 contracts the cylinder rod 13 (arrow A2). Along with this, the arm 14 connected to the cylinder rod 13 moves around the fixed fulcrum 14a, and moves the toggle sleeve 45 forward, that is, in the direction toward the workpiece W (arrow A3).

  As the toggle sleeve 45 moves, the toggle 43 rotates about the fulcrum 43 a and comes into contact with the tapered surface of the toggle sleeve 45. In this state, the corner 43b of the toggle 43 is retracted, and the toggle 43 does not push the push tube 41 forward by the corner 43b. That is, no force from the toggle 43 acts on the push tube 41.

  Before the chuck is closed, that is, when the chuck is open, the toggle 43 pushes the push tube 41 and the chuck opening / closing rod 55, so that the chuck force adjusting spring 56 of the diaphragm chuck portion 101 is contracted with a predetermined force. . Here, when the toggle 43 operates as described above, the chuck force adjusting spring 56 pushes and moves the chuck opening / closing rod 55 in the direction of the arrow A4 by the repulsive force. Thereby, similarly, the push tube 41 is pushed and moved in the direction of the arrow A5. The push tube 41 moving in the arrow A5 direction is locked by the corner 43b of the toggle 43, and the chuck opening / closing rod 55 moving in the arrow A4 direction is locked by the locked push tube 41. Does not move backwards.

  By moving the chuck opening / closing rod 55 in this way, a gap 59 is formed between the end surface of the tip of the chuck opening / closing rod 55 and the end surface of the chuck force adjusting screw 58.

  In a state where the chuck is open, a force is applied to the diaphragm 52 from the chuck opening / closing rod 55 via the chuck force adjusting screw 58, and the diaphragm 52 is deformed so as to protrude toward the workpiece W side. Along with this deformation, the chuck claw 53 is opened. In this operation, the gap 59 is formed between the chuck opening / closing rod 55 and the chuck force adjusting screw 58 as described above, so that the force from the chuck opening / closing rod 55 does not act on the diaphragm 52. Therefore, the diaphragm 52 returns from the convex deformation to the workpiece W side by its restoring force, thereby closing the chuck claw 53. The chuck claw 53 grips the workpiece W by such a force that the chuck claw 53 closes (chuck force).

  Here, the repulsive force of the chuck force adjusting spring 56 also acts on the diaphragm 52. Therefore, the chucking force acting on the workpiece W from the chucking claw 53 can be expressed by the following formula: (chucking force) = (restoring force of the film of the diaphragm 52 itself) − (repulsive force of the chucking force adjusting spring 56).

  The spring force of the chuck force adjusting spring 56 in the automatic lathe 1 is a repulsive force that pushes the end surface of the chuck force adjusting screw 58 via the chuck force adjusting spring receiver 57. As shown in FIG. 3, since the outer diameter of the chucking force adjusting screw 58 and the inner diameter of the diaphragm 52 are screwed together, and the diaphragm 52 and the chuck claw 53 are connected by bolts, the chucking force adjustment is performed. The spring force of the spring 56 acts as a force for opening the chuck claw 53. Therefore, the gripping force cannot exceed the restoring force of the membrane of the diaphragm 52 itself as represented by the above formula.

  Next, a method for adjusting the chucking force will be described. The chucking force is adjusted by changing the spring force of the chucking force adjusting spring 56 by moving the chucking force adjusting screw 58 in the axial direction.

  When the chuck force adjusting screw 58 is moved backward by rotating the hexagonal hole 58a at the center of the chuck force adjusting screw 58 with a hexagon wrench or the like, the chuck force adjusting spring receiver 57 is also moved backward. Thereby, the length of the chuck force adjusting spring 56 is shortened, and the spring force is increased. At this time, according to the above formula, the chucking force is weaker than before the adjustment because of the relative relationship.

  On the other hand, when the chuck force adjusting screw 58 is moved to the left, the chuck force becomes stronger than before the adjustment because the spring force of the chuck force adjusting spring 56 becomes weaker.

(When opening the chuck)
The operation of opening the chuck is basically the reverse of the operation of closing the chuck. First, as shown in FIG. 5, air is sent to the intake port 17 of the cylinder 12 (arrow B1). Thereby, the cylinder 12 extends the cylinder rod 13 (arrow B2). Along with this, the arm 14 connected to the cylinder rod 13 moves around the fixed fulcrum 14a, and moves the toggle sleeve 45 rearward (arrow B3).

  As the toggle sleeve 45 moves, the toggle 43 rotates about the fulcrum 43a, and the end opposite to the fulcrum 43a comes into contact with the inner peripheral surface of the toggle sleeve 45. Thereby, the toggle 43 pushes the end surface of the push tube 41 in the workpiece W direction by the corner portion 43b (arrow B4). That is, the force from the toggle 43 acts on the push tube 41.

  As the push tube 41 moves in the workpiece W direction, the chuck opening / closing rod 55 is also pushed and moved in the direction of the arrow A5. Thereafter, the end face of the tip of the chuck opening / closing rod 55 hits the concave portion of the chuck force adjusting screw 58 and pushes the chuck force adjusting screw 58 and the diaphragm 52 to be screwed in the workpiece W direction.

  The diaphragm 52 is deformed so as to be convex toward the workpiece W side by being pressed by receiving a pressing force from the chuck opening / closing rod 55. As described above, since the diaphragm 52 and the chuck claw 53 are coupled by the bolt, the chuck claw 53 is opened with the deformation of the diaphragm 52.

  Here, a method for adjusting the chuck opening amount will be described. As described above, the chuck opening adjustment nut 42 is screwed to the right end of the main shaft 21 with a screw. When the chuck opening adjustment nut 42 is moved in the axial direction with a screw, the toggle support 44 is also moved in the axial direction. By moving the toggle support 44, the stroke amount that the corner portion 43b of the toggle 43 moves by pushing the push tube 41 can be changed. For example, if the toggle support 44 is moved forward, the stroke amount increases and the chuck opening amount also increases. On the contrary, if the toggle support 44 is moved rearward, the stroke amount is reduced and the chuck opening amount is also reduced.

(Modification of the first embodiment)
Next, a modification of this embodiment will be described. In the automatic lathe 1 of this embodiment, a collet chuck can be used in place of the diaphragm chuck portion 101. First, the configuration of the modification will be described.

  As shown in FIG. 6, the collet chuck portion 103 in this modification includes a collet sleeve 81, a spring 82, a collet chuck 83, and a collet nut 84. The diaphragm chuck 101 in FIG. 1 can be replaced with a collet chuck 103, and other configurations of the automatic lathe 1 are the same as those in FIG.

  Although the rear side of the collet sleeve 81 is formed in a substantially cylindrical shape, a stepped portion is provided on the inner diameter side so that the thickness of the portion including the spring 82 and the collet chuck 83 is reduced. The front part is a thick part, and the inner diameter is tapered toward the workpiece W side. The collet sleeve 81 is inserted into the main shaft 21 from the workpiece W side, and the rear end surface is in contact with the front end surface of the push tube 41.

  The spring 82 is a coil spring that is inserted into the collet sleeve 81 from the workpiece W side and disposed so as to abut against the stepped portion of the collet sleeve 81. The collet chuck 83 is inserted into the collet sleeve 81 following the spring 82. A part of the outer diameter side surface of the collet chuck 83 is formed as a tapered surface that makes contact with the tapered surface on the inner diameter side of the collet sleeve 81 at the same angle. The work W side (head portion) of the collet chuck 83 is provided with a slit 83a so as to be divided into, for example, three parts when viewed from the axial direction. By applying force to the head portion from the outer diameter side, the head portion is The workpiece W can be gripped by reducing the diameter.

  The collet nut 84 is a cap-shaped member that is screwed into the tip end portion of the main shaft 21. A hole is provided in the center of the collet nut 84 when viewed from the axial direction, and the tip of the collet chuck 83 protrudes from the hole toward the workpiece W side. Further, the collet nut 84 abuts on the outer edge of the collet chuck 83, thereby restricting the movement of the collet chuck 83 toward the workpiece W side.

  Next, operation | movement of the automatic lathe 1 provided with the collet chuck | zipper part 103 of this modification is demonstrated.

(When opening the chuck)
When the collet chuck 83 is opened and closed in the collet chuck portion 103 of this modification, the joint for supplying air to the cylinder 12 is different from the case of the diaphragm chuck portion 101 described above. That is, when the collet chuck 83 is opened in the example of FIG. 6, air is supplied to the intake port 18 as shown in FIG. 4 (arrow A1). Accordingly, the cylinder rod 13 (arrow A2), the arm 14, the toggle sleeve 45 (arrow A3), the toggle 43, and the like operate in the same manner as in FIG.

  Before this operation, that is, when the chuck is closed, the toggle 43 pushes the push tube 41 and the collet sleeve 81, so that the spring 82 of the collet chuck portion 103 is contracted by a predetermined force. Since the force from the toggle 43 does not act on the push tube 41 by the opening operation of the chuck, the spring 82 pushes and moves the collet sleeve 81 and the push tube 41 backward by the repulsive force (arrow C1).

  At this time, as the collet sleeve 81 moves, the taper surface thereof is also displaced rearward, so that the deformation of the head portion of the collet chuck 83 that is sandwiched between the collet sleeve 81 from the outer diameter side and elastically deformed to the inner diameter side is restored. . As a result, the diameter of the collet chuck 83 is increased and the gripping surface 83b is opened.

(When closing the chuck)
The operation of closing the chuck in the collet chuck 103 is basically the reverse of the operation of opening the chuck described above. That is, as shown in FIG. 5 described above, air is first supplied to the intake port 17 of the cylinder 12 (arrow B1). Accordingly, the cylinder rod 13 (arrow B2), the arm 14, the toggle sleeve 45 (arrow B3), the toggle 43, the push tube 41 (arrow B4) and the like operate in the same manner as in FIG.

  As the push tube 41 moves in the direction of arrow B4, that is, in the direction of arrow C2 in FIG. 6, the collet sleeve 81 is similarly pushed and moved in the direction of arrow C2. As a result, the head portion of the collet chuck 83 is pressed from the outside to reduce the diameter. As a result, the collet chuck 83 can grip the workpiece W by closing the gripping surface 83b.

  As described above, according to this embodiment, the chuck device including the diaphragm at the tip of the main shaft can be provided with a simple and compact configuration. In particular, by using a widely used toggle drive, it is possible to easily and inexpensively attach a chuck device using a diaphragm to the end of the main shaft without changing the main shaft. Thereby, the diaphragm chuck which can be processed with high coaxial accuracy and can prevent chips from entering the chuck and the main shaft can be used more effectively.

  Further, the collet chuck and the diaphragm chuck can be shared, and each chuck portion can be easily mounted on the main shaft. Accordingly, the diaphragm chuck and the collet chuck can be properly used with one lathe according to the application, and the processing efficiency can be improved. Furthermore, since there are many parts shared by the diaphragm chuck and the collet chuck, it is possible to reduce manufacturing costs and storage costs.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. In the following description, the same components as those described above are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 7, the automatic lathe 2 of the present embodiment includes a diaphragm chuck portion 102 instead of the diaphragm chuck portion 101 described above. The diaphragm chuck portion 102 is different from the diaphragm chuck portion 101 in that it does not include a mechanism for adjusting the chucking force. The diaphragm chuck portion 102 includes a holding member 72, a diaphragm 73, and an opening / closing rod return spring 71, in addition to the chuck pawl 53 and the chuck opening / closing rod 55 common to the diaphragm chuck portion 101.

  The holding member 72 is screwed into the front end portion of the main shaft 21. The holding member 72 holds the diaphragm 73 on the front end surface including, for example, six screw holes. The holding member 72 has a substantially cylindrical shape, but the inner diameter of a part of the inner periphery is smaller than the others, and the outer peripheral surface of the convex portion on the rear side of the diaphragm 73 is held by the inner peripheral surface of this part. Yes.

  The diaphragm 73 is a member having a plate-like portion that undergoes predetermined elastic deformation (film deformation) with respect to an external force, and is attached to the holding member 72 with a bolt. Further, the diaphragm 73 includes, for example, six screw holes for holding the chuck claws 53 on the front end face. Further, the diaphragm 73 is hollow, and a convex portion is formed on the rear side of the center portion of the shaft, and a concave portion 73a similar to the chucking force adjusting screw 58 is provided at the central portion of the convex portion. Yes.

  The open / close rod return spring 71 is a coil spring disposed between the chuck open / close rod 55 and the holding member 72. The opening / closing rod return spring 71 has a different use from the chuck force adjustment spring 56 in the diaphragm chuck portion 101. As shown in FIG. 7, when the chuck is closed, a gap 74 is generated between the chuck opening / closing rod 55 and the diaphragm 73 (described later). Since there is this gap, the chuck opening / closing rod 55 and the push tube 41 are not fixed and can move in the axial direction. Thereby, when the main shaft 21 is rotated to process the workpiece W, noise may be generated. Further, when the end face of the tip of the chuck opening / closing rod 55 moves and hits the end face of the diaphragm 73, the chucking force of the chuck claws 53 may change, which may affect the processing accuracy. Therefore, the chuck opening / closing rod 55 and the push tube 41 are fixed by pressing the end surface of the holding member 72 and the end surface of the chuck opening / closing rod 55 with the opening / closing rod return spring 71.

  Next, the operation of the automatic lathe 2 configured as described above will be described.

(When closing the chuck)
When the chuck is closed in the diaphragm chuck portion 102 of the automatic lathe 2, it is the same as when the chuck is closed in the diaphragm chuck portion 101 described above. That is, as shown in FIG. 4, first, air is supplied to the intake port 18 (arrow A1). Accordingly, the cylinder rod 13 (arrow A2), the arm 14, the toggle sleeve 45 (arrow A3), the toggle 43, and the like operate in the same manner as in FIG.

  Since the force from the toggle 43 does not act on the push tube 41, the chuck opening / closing rod 55 and the push tube 41 move backward (arrow D1) by the spring force (repulsive force) of the open / close rod return spring 71. This operation is also the same as in FIG. 4 (arrow A4, arrow A5).

  By moving the chuck opening / closing rod 55 in this way, a gap 74 is formed between the end surface of the tip of the chuck opening / closing rod 55 and the end surface of the diaphragm 73.

  When the chuck is open, a pressing force is applied to the diaphragm 73 from the chuck opening / closing rod 55, and the diaphragm 73 is deformed so as to protrude toward the workpiece W side. Along with this deformation, the chuck claw 53 is opened. In this operation, since the gap 74 is formed between the chuck opening / closing rod 55 and the diaphragm 73 as described above, the force from the chuck opening / closing rod 55 does not act on the diaphragm 73. Therefore, the diaphragm 73 returns from the convex deformation to the workpiece W side by its restoring force, thereby closing the chuck claw 53. The chuck claw 53 grips the workpiece W by such a force that the chuck claw 53 closes (chuck force).

(When opening the chuck)
The case where the chuck is opened by the diaphragm chuck unit 102 is the same as the case where the chuck is opened by the diaphragm chuck unit 101 described above. As shown in FIG. 5, first, air is supplied to the intake port 17 of the cylinder 12 (arrow B1). Accordingly, the cylinder rod 13 (arrow B2), the arm 14, the toggle sleeve 45 (arrow B3), the toggle 43, the push tube 41 (arrow B4) and the like operate in the same manner as in FIG.

  Accordingly, the chuck opening / closing rod 55 is pushed by the push tube 41 and moves in the direction of arrow E1 (arrow B5 in FIG. 5) in FIG. After that, the end face of the tip of the chuck opening / closing rod 55 abuts against the concave portion of the diaphragm 73, thereby pushing the diaphragm 73 toward the workpiece W side.

  The diaphragm 73 is deformed so as to be convex toward the workpiece W side by being pushed from the chuck opening / closing rod 55. As described above, since the diaphragm 73 and the chuck claw 53 are coupled by the bolt, the chuck claw 53 opens as the diaphragm 73 is deformed.

  As described above, it is also possible to configure the diaphragm chuck unit 102 without the chuck force adjusting mechanism as in the present embodiment. It should be noted that the automatic lathe 2 of the present embodiment can also be used by being replaced with the collet chuck portion 103 instead of the diaphragm chuck portion 102 as a modification.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG.

  The automatic lathe 3 according to this embodiment includes a spindle stock 11 and a back spindle stock 91. The head stock 11 and the rear head stock 91 are installed on a common bed 95.

  On the main shaft side, a collet chuck portion 103 according to a modification of the first embodiment described above is provided. Except for the chuck portion, the configuration of the automatic lathe 1 of FIG.

  The diaphragm chuck portion 101 of the first embodiment described above is provided on the back spindle side. This configuration is the same as that of the automatic lathe 1 in FIG. 1, the back spindle 91 corresponds to the spindle 11 in FIG. 1, and the back spindle 92 corresponds to the spindle 21 in FIG. 1.

  FIG. 9 shows an operation example of the automatic lathe 3 of the present embodiment. FIG. 9 shows an example in which the work W0, which is a rod-shaped material, is held by the collet chuck 83 on the spindle side and is processed by the tool 93. In this example, the machined workpiece W0 is then moved to the rear spindle side and chucked by the operation of the diaphragm 52, the chuck claw 53, and the like. And it can process with the precision tool which requires the coaxial precision of the work W and the location to process, for example with a parting tool (not shown) by the side of the back spindle. Thus, according to this embodiment, a highly accurate workpiece can be processed continuously from a single rod-shaped material (work).

  In addition, this invention is not limited to embodiment mentioned above and a specific example, A various deformation | transformation and application are possible.

  For example, in each of the embodiments described above, the push tube 41 and the chuck opening / closing rod 55 are separate members, but they may be configured to be integrated.

  The cylinder 12 is operated by air, but is not limited to air and may be operated by hydraulic pressure. In this case, a fuel filler port can be provided in place of the intake port 17 and the intake port 18.

  Further, a servo motor may be used instead of the cylinder 12. In this case, in order to cause the toggle sleeve 45 to perform a predetermined operation, a power transmission member can be appropriately used instead of the cylinder rod 13 and the arm 14.

  Further, the spindle stock (or the back spindle stock) may move in the Z axis or the X axis without being fixed and moving.

  Further, the combination of the main spindle side and the rear main spindle side in the third embodiment is not limited to FIG. 9, and the diaphragm chuck portion 101, the diaphragm chuck portion 102, and the collet chuck portion 103 can be arbitrarily combined.

  Further, the chuck force adjusting spring 56, the open / close rod return spring 71, and the spring 82 are not limited to coil springs, and may be any elastic body that biases the spring force.

  Further, the pressing member (the push tube 41, the chuck opening / closing rod 55) and the chuck force adjusting screw 58 may be hollow or may not be hollow.

1-3 Automatic lathe (Lathe)
11 Spindle table 12 Cylinder 13 Cylinder rod 14 Arm 16, 95 Bed 17, 18 Air inlet 21 Spindle (rotary shaft)
22, 23 Bearing 31 Built-in motor 32 Stator 33 Rotor 41 Push tube (pressing member)
42 Chuck opening adjustment nut 43 Toggle 44 Toggle support 45 Toggle sleeve 46 Bearing 51, 72 Holding member 52, 73 Diaphragm 53 Chuck claw (gripping member)
55 Chuck Open / Close Rod (Pressing Member)
56 Chuck force adjustment spring (spring member)
57 Chuck force adjustment spring receiver (intermediate member)
58 Chuck force adjustment screw (adjustment screw)
59, 74 Clearance 71 Opening / closing rod return spring (spring member)
81 Collet sleeve 82 Spring 83 Collet chuck 84 Collet nut 91 Back spindle base 92 Back spindle 93 Tools 101, 102 Diaphragm chuck (chuck device)
103 Collet chuck (Collet chuck device)
111 Toggle switching part (pressing mechanism)
W, W0 Workpiece (Holding object)

Claims (13)

A holding member disposed so as to be screwed to the tip of the rotating shaft;
A diaphragm that is held by the holding member and elastically deforms by receiving a predetermined pressing force in the axial direction of the rotating shaft;
A gripping member provided on the surface of the diaphragm, and comprising a plurality of claws for gripping a gripping object;
A pressing member that is disposed so as to be inserted through the rotating shaft in the axial direction, and that applies the pressing force toward the gripping object with respect to the diaphragm;
A spring member that biases a predetermined spring force in a direction opposite to the pressing direction with respect to the pressing member,
A chuck device characterized by that. A toggle that is pivotably supported; and a pressing mechanism that urges the pressing member in the pressing direction by the toggle.
The chuck device according to claim 1, wherein: The diaphragm further includes an adjusting screw that is screwed into a central portion of the diaphragm,
The adjustment screw includes a pressure receiving surface that comes into contact with the pressing member, and is capable of adjusting an interval between the pressure receiving surface and the pressing member.
The chuck device according to claim 1 or 2, wherein An intermediate member that is disposed between the adjustment screw and the spring member and transmits a reaction of the spring force to the diaphragm via the adjustment screw;
The chuck device according to claim 3. The adjustment screw includes a recess into which a tip portion of the pressing member is inserted on a surface facing the pressing member.
The chuck device according to claim 3 or 4, wherein The pressing member and the adjustment screw are both hollow in the axial direction.
The chuck device according to any one of claims 3 to 5, wherein: The diaphragm includes a recess into which a front end portion of the pressing member is inserted on a surface facing the pressing member.
The chuck device according to claim 1 or 2, wherein The spring member is disposed between the pressing member and the holding member.
The chuck device according to claim 7. The pressing member and the diaphragm are both hollow in the axial direction.
The chuck device according to claim 7 or 8, wherein The pressing member is divided into a plurality in the axial direction.
The chuck device according to any one of claims 1 to 9, wherein: A headstock,
A spindle rotatably supported on the spindle stock;
A chuck device according to any one of claims 1 to 10, provided on the main shaft,
A lathe characterized by that. A headstock,
A spindle rotatably supported on the spindle stock;
A back spindle stock arranged opposite to the spindle stock;
A back spindle rotatably supported on the back spindle stock;
The chuck device according to any one of claims 1 to 10, provided on one or both of the main shaft and the back main shaft.
A lathe characterized by that. A collet chuck having a tapered surface formed on the outer peripheral portion and gripping a gripping object;
A collet chuck device comprising: a collet sleeve that is fitted to the tapered surface of the collet chuck to close the collet chuck by receiving the pressing force from the pressing member;
The collet chuck device and the chuck device including the diaphragm have mounting compatibility.
The lathe according to claim 11 or 12, characterized in that.

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