WO2005089987A1

WO2005089987A1 - Machine tool with work spindle and material machining method by the same

Info

Publication number: WO2005089987A1
Application number: PCT/JP2004/003727
Authority: WO
Inventors: Toshiyuki Suzuki
Original assignee: Citizen Watch Co. Ltd.
Priority date: 2004-03-19
Filing date: 2004-03-19
Publication date: 2005-09-29

Abstract

A machine tool (10), comprising a work spindle (12) capable of holding and rotating a work material (W), a tool mounting part (16) fitted to the work spindle so as to be operated together with the work spindle and to which a tool (14) is fitted, an operating mechanism (18) operating the work spindle, and a rotatable second work spindle (24) formed separately from the work spindle (12). The tool mounting part (16) further comprises a plurality of tool holding parts (22) disposed on the work spindle about the rotating axis (12a) thereof at specified intervals in the circumferential direction. The control device (20) of the operating mechanism (18) indexes and rotates the work spindle so that the plurality of tools fitted to the plurality of tool holding parts can be selectively positioned at their respective work positions (P). Also the control device (20) can make the tool fitted to the tool mounting part operate to cut a work material (W’) held on the second work spindle.

Description

Description Machine tool equipped with a work spindle and its material processing method

The present invention relates to a machine tool provided with a work spindle. The present invention further relates to a material processing method for a machine tool having a work spindle. Background art

A machine tool equipped with a plurality of spindles (hereinafter referred to as workpiece spindles) each capable of holding and rotating a workpiece (workpieces) is, for example, an automatic machine represented by an NC (numerical control) lathe. Known for lathes (ie lathes that can be machined automatically). In this type of machine tool, multiple work spindles and multiple turrets are collectively mounted on a single machine to reduce machining time, and the operation of these work spindles and turrets is individually controlled. In addition, multi-functionalization has been promoted to enable simultaneous processing of different types (for example, outer diameter cutting and boring) of the same workpiece, and simultaneous processing of different workpieces. Also, the turret is equipped with various types of tools such as piles, drills, milling cutters, etc. that can be exchanged, and performs turning, drilling, and milling on workpieces gripped by individual work spindles. Various processing steps, such as, can be performed, so that complex and various shaped machined products can be automatically processed.

For example, Japanese Patent Laid-Open Publication No. Hei 6-703 (JP 6-703 A) describes a pair of work spindles that can be arranged coaxially facing each other in the direction of the rotation axis, and a plurality of tools are mounted on each of them. The operation of the pair of turrets and the work spindle and the turret are individually controlled, and the different Disclosed is an NC lathe including an NC device that performs simultaneous processing on a workpiece. As a tool post, a turret tool post that indexes a tool by rotating motion is used.

In addition, Japanese Patent Application Laid-Open Publication No. Hei 10-510758 (JP10-5017758A) and Japanese Patent No. 27774243 (JP277774243) Each of B 2) includes a pair of peak spindles that can be arranged coaxially facing each other in the axial direction, and a pair of turret turrets, each of which mounts a plurality of tools and operates independently. Disclosed is an NC lathe that enables simultaneous processing of different workpieces held on a work spindle. In recent years, with the promotion of multifunctionality in machine tools, it has been required to further increase the number of tools previously mounted on the turret, which can be continuously used during the execution of a machining program. In order to increase the number of mountable tools on the turret, as described in the above-mentioned related art publications, a turret having a plurality of tool holding portions spaced apart in the circumferential direction around the rotation axis. It is common to use a tool post.

Here, since the turret tool rest performs the feed operation and the indexing operation of the tool by different operations, it has a large number of control axes and a relatively complicated structure. In addition, the turret turret has a sufficient distance between the center of rotation and the tool cutting edge to avoid interference between the mounted tool and the workpiece, and as a result, is relatively large as a whole Tend. Therefore, increasing the number of tool holders on the turret turret or increasing the number of turret turrets for the purpose of increasing the number of tools that can be mounted on the turret is not the same as the structure of the machine tool. This can lead to increased control complexity and overall size, leading to higher manufacturing and operating costs. Also, adding a turret turret to an existing machine tool is not feasible, since it requires a major modification of the machine structure. From this point of view, there is also known a machine tool in which a so-called comb tooth turret capable of mounting a plurality of tools in a parallel arrangement and a turret turret are provided. Although the number of tools that can be mounted on the comb turret is smaller than that of the turret turret, the tool feed operation and indexing operation can be performed with the same feed control axis, making it easier than the turret turret. It has a simple structure. However, it is still not practical to equip a comb turret that satisfies the required number of tools.

Furthermore, in conventional machine tools, generally, regardless of the type of tool post, the mounted tools are exchanged on the machine tool, and the position of the cutting edge is corrected as necessary. As the number of tools that can be mounted on the tool post increases, it is desired to reduce the time and labor required for such changeover. Disclosure of the invention

Therefore, an object of the present invention is to increase the number of mountable tools as a tool post total in a machine tool having a work spindle without complicating the machine structure and operation control or increasing the overall size. It is an object of the present invention to provide a machine tool capable of performing such operations.

Another object of the present invention is a material processing method for a machine tool having a work spindle, which does not complicate the operation control even when the number of mountable tools as the total tool post is increased. An object of the present invention is to provide a material processing method capable of processing a workpiece by a desired tool.

In order to achieve the above object, the present invention provides a work spindle, which is capable of gripping and rotating a work material, a tool mounting part which is installed on the work spindle so as to be operable with the work spindle, and to which a tool is attached; And a machine tool comprising:

In the above machine tool, the operating mechanism indexes the work spindle to rotate. A control device for positioning the tool attached to the tool attachment portion to a predetermined work position.

In this configuration, the tool mounting section has a plurality of tool holding sections that are arranged in the circumferential direction with the rotation axis of the work spindle as a center, and the control device controls each of the plurality of tools mounted on the plurality of tool holding sections. It is advantageous to selectively position the in the working position.

Further, the operating mechanism may include a control device that causes the tool attached to the tool attaching portion to perform a cutting operation on the workpiece.

In this configuration, it is preferable that the control device controls the cutting operation in a state where the work spindle holds another workpiece.

Alternatively, the work spindle may include a discharge mechanism for discharging the workpiece gripped by the work spindle, and in this case, the control device may control the cutting operation in a state where the discharge mechanism is discharged. preferable. The discharge mechanism may have a knockout bin.

Further, the discharging mechanism may include a compressed air discharging device. The work spindle includes a hollow cylindrical spindle main body, a chuck installed in an end area of the spindle main body, and a holding member for holding a chuck in an end area of the spindle main body, and a tool attached to the holding member. It is possible to adopt a configuration in which a section is provided.

In this configuration, it is advantageous that a positioning element for positioning the tool mounting portion in the rotation direction of the work spindle is provided between the main spindle body and the holding member.

Further, it is advantageous that a fitting portion for centering the tool mounting portion with respect to the rotation axis of the work spindle is provided between the main spindle body and the holding member. The holding member is a second holding device having no tool mounting portion. Advantageously, it is interchangeable with the component. The tool attached to the tool attachment can be a throw-away tip.

Further, a rotatable second work spindle separate from the work spindle can be further provided, and in this case, the operating mechanism is configured to mount the tool to the workpiece gripped by the second work spindle. The tool attached to the part can be cut.

In this configuration, the work spindle having the tool mounting portion can be a back spindle that can rotate while gripping the partially-processed workpiece delivered from the second work spindle.

In addition, the control device can rotate the second work spindle to cause the tool attached to the tool mounting portion to perform turning on the workpiece held by the second work spindle.

Alternatively, the control device can rotate the work spindle having the tool attachment portion, and cause the tool attached to the tool attachment portion to perform the milling process on the workpiece gripped by the second work spindle.

Alternatively, the control device may rotate the work spindle having the tool mounting portion and the second work spindle in synchronization with each other so that the workpiece mounted on the tool mounted on the tool mounting portion is gripped by the second work spindle. Can be polygon-processed.

The present invention further relates to a material processing method for a machine tool having a plurality of workpiece spindles separated from each other, wherein a tool is attached to a first workpiece spindle, and a workpiece is gripped by a second workpiece spindle. The present invention also provides a material processing method in which the first and second work spindles are operated, and the workpiece is machined by a tool attached to the first work spindle.

In this material processing method, the first work spindle can be operated so that the spindle function and the turret function are continuously performed in the machining program. Brief Description of Drawings

The above and other objects, features, and advantages of the present invention will become more apparent from the following description of preferred embodiments with reference to the accompanying drawings. In the accompanying drawings,

FIG. 1 is a schematic diagram showing a basic configuration of a machine tool according to the present invention. FIG. 2A is a diagram showing a work spindle of the machine tool according to the first embodiment of the present invention. Sectional view along

FIG. 2B is a diagram showing the axial end face of the work spindle shown in FIG. 2A, and a diagram for explaining a method of aligning the cutting edge;

FIG. 3A is a diagram showing a work spindle of a machine tool according to a second embodiment of the present invention, and is a sectional view similar to FIG. 2A,

FIG. 3B is a diagram showing an axial end face of the work spindle of FIG. 3A, FIG. 4A is a cross-sectional view showing a modification of the work spindle of FIG. 3A,

FIG.4B is a diagram showing an axial end face of a modification of FIG.4A,

FIG. 5 is a view showing a work spindle of a machine tool according to a third embodiment of the present invention, and is a sectional view similar to FIG. 2A,

FIG. 6 is a sectional view showing a modification of the work spindle of FIG. 5,

FIG. 7 is a schematic view showing a layout example of a work spindle and a tool post of a machine tool according to the present invention,

8A and 8B are views for explaining an example of a material processing method according to the present invention, and

9A to 9D are diagrams illustrating another example of the material processing method according to the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same or similar components have common reference numerals. Attach.

Referring to the drawings, FIG. 1 shows a basic configuration of a machine tool 10 according to the present invention. The machine tool 10 is mounted on the workpiece spindle 12 so as to be operable with the workpiece spindle 12 and the workpiece spindle 12, which can hold and rotate the workpiece W, and a tool mounting portion to which the tool 14 is attached. 16 and an operating mechanism 18 for operating the work spindle 12.

According to the machine tool 10 having such a basic configuration, the work spindle 12 functions as a turret, and the tool 14 attached to the tool mounting portion 16 allows the machine tool 10 Other workpieces W 'placed on a table (not shown) can be processed. With this configuration, the number of tools that can be mounted in advance as the entire tool post in the machine tool 10 increases without additionally providing a tool post as a new moving structure. In this case, the existing operation mechanism 18 (including hardware and software) for operating the work spindle 12 can be used as it is, so that the mechanical structure and operation control of the machine tool 10 are complicated and the overall dimensions are reduced. There is no increase.

The operating mechanism 18 can include a control device 20 for indexing and rotating the work spindle 12. The control device 20 positions the tool 14 attached to the tool mounting portion 16 at a predetermined work position (for example, position P) on a machine base (not shown) of the machine tool 10. In particular, as shown in the figure, it is advantageous that the tool mounting portion 16 has a plurality of tool holding portions 22 which are arranged in the circumferential direction with the rotation axis 12 a of the work spindle 12 as a center. In this case, the control device 20 indexes and rotates the work spindle 12 so that each of the plurality of tools 14 attached to the plurality of tool holders 22 is selectively positioned at the work position P. Let it.

In addition, the control device 20 of the operating mechanism 18 can perform the cutting operation of the tool 14 attached to the tool mounting portion 16 on the workpiece W ′. The By providing such a control device 20, the work spindle 12 functions as a turret tool post, and the workpiece W can be processed by the various tools 14 mounted on the tool mounting portion 16. The machine tool 10 that can perform various machining processes such as turning, drilling, milling, etc., can automatically process workpieces of complex and various shapes. It is advantageous to further provide a rotatable second work spindle 24 separate from the work spindle 12. In this configuration, the operation mechanism 18 can perform the cutting operation of the tool 14 attached to the tool attachment portion 16 on the workpiece W ′ gripped by the second work spindle 24.

The first work spindle 12 and the second work spindle 24 are basically arranged such that their respective rotation axes 12 a and 24 a are parallel to each other. And preferably, the first and second work spindles 12 and 24 are arranged so as to be coaxially opposed to each other in the rotational axis direction, as shown in the drawing, and the operating mechanism 18 is provided with the first and second work spindles. Either one or both of the work spindles 12 and 24 can be moved relatively along at least one of two orthogonal axes (for example, a-axis and axis) set on a machine base (not shown). It is configured to be able to.

In this configuration, either one of the work spindles 12 and 24 constitutes a main front spindle that can grip and rotate the unprocessed workpiece supplied from the outside in an automatic lathe, and The work spindles 12 and 24 can form a supplementary back spindle which can rotate by gripping a partially processed workpiece delivered from the front spindle.

In this configuration, the tool mounting portion 16 can be provided not only on the first work spindle 12 but also on the second work spindle 24. In this case, the operating mechanism 18 is connected to the By operating the work spindle 24 of No. 2 as a tool post, the workpiece W gripped by the first work spindle 12 can be machined by the tool 14 mounted on the tool mounting portion 16 thereof. . Further, the present invention can be applied to a machine tool having three or more work spindles.

Next, some preferred embodiments of the machine tool according to the present invention will be described with reference to FIGS. 2A to 6. Each of these embodiments relates to an automatic lathe. The illustrated work spindle is capable of gripping and rotating a partially-processed workpiece delivered from a front spindle (second work spindle). It is configured as a simple auxiliary back spindle.

2A and 2B show a work spindle 30 of the machine tool according to the first embodiment of the present invention. The work spindle 30 includes a hollow cylindrical spindle main body 32 having a rotation axis 32a, a chuck 34 installed in an axial end region 32b of the spindle main body 32, and a chuck 34. And a holding member 36 for holding the main body 32 in an end region 32b. The holding member 36 is provided with the tool mounting portion 16 described above.

The spindle main body 32 is rotatably mounted on the headstock 40 via a bearing device 38, and is operatively connected to a rotary drive source (not shown) such as a servomotor. A rod-shaped workpiece (not shown) is fed to the spindle main body 32 through the open chuck 34 in the axial direction. Then, in a state where the workpiece is firmly gripped by the chuck 34 by the operation of the operation member described later, the spindle main body 32 is rotationally driven by the rotational drive source about the axis 32a.

The spindle main body 32 is driven by a rotary drive source included in the operating mechanism 18 in Fig. 1 to perform high-speed rotary motion (speed control) for turning, which is the main function, and milling, which is a supplementary function. It is configured to be able to perform the rotary indexing motion (C-axis position control) for cutting. Also, headstock 4 0 Under the drive of the feeder included in the operating mechanism 18 in FIG. 1, for example, the control axis (Z axis) direction parallel to the central axis 32a and the control axis (X axis) orthogonal to the Z axis It is configured to be able to perform a feeding operation in the direction.

The chuck 34 is a hollow cylindrical body having a center axis 34 a and capable of receiving a workpiece therein, and has a center axis 34 at the front end in the axial direction (the right end in FIG. 2A). A grip portion 42 having a slotted structure is provided in which the inner diameter can be elastically changed (that is, opened and closed) with reference to a. The holding portion 42 includes a plurality (three in FIG. 2B) of axial slits 44 engraved over an appropriate length from the front end in the axial direction of the chuck 34. Each of the vertical split pieces 46 formed between the directional slits 44 can be elastically displaced in the radial direction like a leaf spring.

The gripping portions 42 of the chucks 34 uniformly apply an external force inward in the radial direction to the plurality of vertically split pieces 4 6 to elastically bend from an initial position. The workpiece is firmly and firmly gripped by reducing the diameter of the workpiece until it comes into close contact with the workpiece. When the radial pressure on the gripper 42 is released, the plurality of vertical split pieces 46 are elastically restored to the initial position, the inner peripheral surface is enlarged, and the workpiece is released from the gripper 42. Is done.

The gripping portion 42 of the chuck 34 has a frusto-conical pressure receiving surface 4 that gradually increases in diameter toward the front end in the axial direction of the chuck 34 along the outer surface of the plurality of vertical split pieces 46. 8 is formed. The pressure receiving surface 48 is formed at a position separated from the front end surface in the axial direction of the grip portion 42 in the axial rearward direction, and is adjacent to the large-diameter end of the pressure receiving surface 48 and located at the center axis 34 a. A substantially orthogonal annular shoulder surface 50 is formed.

A hollow cylindrical operating member 52 having a center axis 52 a is interposed between the spindle main body 32 and the chuck 34. The operating member 52 accommodates the chuck 34 in its axial front end (right end in FIG. 2A) in a concentric manner so as to be slidable in the axial direction, while the axial front end of the main spindle body 32 (FIG. 2A). (Right end at A) Region is concentrically accommodated so that it can slide in the axial direction.

A frustoconical working surface 54 engageable with a pressure receiving surface 48 provided on the gripper 42 of the chuck 34 is formed on the annular inner surface of the front end region in the axial direction of the operating member 52. You. The working surface 54 extends gradually from the front end face in the axial direction of the operating member 52 toward the rear in the axial direction with a reduced diameter, and constitutes a pressurizing surface that is annularly contacted with the pressure receiving surface 48.

The operating member 52 further accommodates an elastic member 56 made of, for example, a compression coil spring adjacent to the chuck 34 in the axial rearward direction. The elastic member 56 always elastically urges the chuck 34 toward the axial front end of the operating member 52 (that is, the direction in which the pressure receiving surface 48 is separated from the operating surface 54).

The holding member 36 is a hollow cap-shaped member having a center axis 36 a, and is detachably attached to the front end in the axial direction of the main spindle body 32. The holding member 36 is provided with a female screw 58 at the rear end in the axial direction (the left end in FIG. 2A), and is screwed into the female screw 58 at the front end in the axial direction of the main spindle body 32. Male threads 60 are provided.

In addition, an annular locking surface 62 substantially perpendicular to the central axis 36a is formed on the inner surface of the front end region (right end in FIG. 2A) of the holding member 36 in the axial direction. The locking surface 62 has a shape and dimensions capable of engaging with the shoulder surface 50 provided on the grip portion 42 of the chuck 34. When the holding member 36 is attached to the front end of the spindle main body 32 with the chuck 34 and the elastic member 56 properly accommodated in the operating member 52, the locking surface 62 becomes the shoulder surface 5 of the chuck 34. 0, and holds the chuck 34 so as not to drop from the operating member 52 against the bias of the elastic member 56.

When the workpiece is gripped by the chuck 34, the operating member 52 receives a driving force from a driving unit (not shown) at its rear end face 52 b in the axial direction, and moves in the axial direction from the main spindle body 32. Move so that it is pushed forward The At this time, the chuck 34 is fixedly arranged with respect to the spindle main body 32 by abutment between the shoulder surface 50 and the locking surface 62 of the holding member 36. 2 moves axially forward with respect to the spindle main body 32 and the chuck 34, and the working surface 54 of the operating member 52 presses the pressure receiving surface 48 of the chuck 34. As a result, the gripper 42 of the chuck 34 naturally reduces its diameter, and firmly grips the workpiece.

When the chuck 34 is opened, if the driving force from the drive unit to the operating member 52 is released, the elastic member 56 biases the operating member 52 so that the spindle main body 32 and the chuck 3 4 , The pressing force from the working surface 54 of the operating member 52 to the pressure receiving surface 48 of the chuck 34 is released. As a result, the gripper 42 of the chuck 34 restores elasticity and expands its diameter, releasing the workpiece.

The spindle main body 32, chuck 34, holding member 36 and operating member 52 constituting the work spindle 30 align their respective axes 32a, 34a, 36a and 52a with each other. Assembled together. The configuration of the work spindle 30 described above is known as the configuration of the back spindle of the automatic lathe. In addition to this, in the work spindle 30 according to the present invention, the holding member 36 is provided with a recess 64 extending annularly around the axis 36 a in the axial front end region of the outer surface thereof. An annular mounting member 66 is fixedly received in the recess 64, thereby forming a tool mounting portion 16.

The holding member 36 and the mounting member 66 are made of the same rigid material as the tool holder installed on a general tool rest. And the holding member 3

The mounting member 66 having a complementary substantially rectangular cross section is received without looseness in the substantially rectangular recessed portion 64 of FIG. 6, and is fixed by a fastening element 68 such as a port. The mounting member 66 has a plurality of (four in the figure) grooves 70 arranged at one end surface in the axial direction at substantially equal intervals in the circumferential direction. This Each of these grooves 70 constitutes the above-mentioned tool holding portion 22 (FIG. 1), and each of the grooves 70 has a cutting edge protruding outward in the radial direction of the mounting member 66. 14 is attached.

Each groove 70 of the mounting member 66 has a substantially trapezoidal profile in the end view of FIG. 2B, and the tool 14 mounted in the groove 70 partially matches the trapezoidal profile of the groove 70. It has a parallelogram outline. Therefore, each tool 14 is complementarily received in the corresponding groove 70 of the mounting member 66 without play, and is fixed at a predetermined position by a fastening element 72 such as a port.

Each tool 14 mounted on the mounting member 6 6 on the holding member 3 6 controls the indexing rotation control axis (C axis) for the workpiece to be gripped, which is one of the spindle functions of the peak spindle 30. It is used to selectively position at a predetermined working position on a machine base (not shown). Therefore, in order to accurately determine the tool 14 at the working position, the tool mounting part 16 (the holding member 36 and the mounting member 66) is provided between the main spindle body 32 and the holding member 36. A positioning element 74 is provided for mechanical positioning in the zero rotation direction.

In the illustrated embodiment, the positioning element 74 is provided with a female screw 58 provided on the holding member 36, a male screw 60 provided on the spindle main body 32, and a mounting member 66. And a plurality (four in the figure) of elongated holes 76 through which are inserted. When attaching the holding member 36 to the main spindle body 32, the female screw 58 is firmly tightened to the male screw 60 with a predetermined torque, so that the holding member 36 is fixed in the rotational direction with respect to the main spindle body 32. You.

Further, by fastening the fastening element 68 inserted into the elongated hole 76 of the mounting member 66 at an appropriate position with respect to the elongated hole 76, the mounting member 66 rotates relative to the holding member 36. Fixed in the direction. At this time, before completely tightening the fastening elements 68, the work spindle 30 is moved to a specific rotational position. (Preferably at the C-axis origin), and in this state, the cutting edge of one tool 14 mounted on the mounting member 66 is brought into contact with, for example, a reference stationary surface 78 set in advance on the machine base. Then, in this contact state, the fastening element 68 is completely tightened, and the mounting member 66 is fixed to the holding member 36. As a result, the tool mounting portion 16 is mechanically positioned at a predetermined position in the rotation direction, and the cutting edge position of each tool 14 is specified on the C axis of the work spindle 30. As a result, each tool 14 can be accurately indexed to the working position by the C-axis control of the control device 20 (FIG. 1) of the operating mechanism 18.

The work spindle 30 is an indexing rotation control axis as one of the spindle functions.

If a (C-axis) angle detector is provided, instead of the above procedure, tighten the fastening element 6 8 before attaching the cutting edge of the tool 14 to the reference stationary surface 78. 6 can be fixed to the holding member 36. In this case, the rotation position where the cutting edge of the tool 14 abuts on the reference stationary surface 78 is detected by the angle detector, and based on this rotation position, the controller 20 (Fig. 1) presets C Correct the axis origin. As a result, in the subsequent machining program, each tool 14 can be accurately determined at the work position using the capture origin.

Each of the tools 14 mounted on the mounting member 66 on the holding member 36 is further provided with a feed control axis (X axis and X axis) for the workpiece to be gripped, which is one of the main spindle functions of the work spindle 30. The cutting edge is configured to perform an interpolation cutting operation on a machine base (not shown) using the Z axis). Therefore, the plurality of tools 14 attached to the tool attachment portion 16 (the holding member 36 and the attachment member 66) are arranged such that each of the cutting edges has a rotation axis of the work spindle 30 (the axis 3 of the spindle body 32). 2) It must be fixedly held at a predetermined distance from a). Also, the tool mounting part 16 is firmly fixed to the proper position on the spindle main body 32 so as not to be displaced in the radial direction under external force such as cutting resistance applied to the tool 14 during machining work. Need to be retained There is.

For that purpose, as described above, the tool 14 is complementarily received and fixed in the corresponding groove 70 of the mounting member 66 without play. Also, as described above, when the female screw 58 of the holding member 36 is firmly tightened to the male screw 60 of the spindle main body 32, the annular end face 32c provided at the front end in the axial direction of the spindle main body 32 is formed. It is advantageous that the annular second locking surface 36 b provided on the inner surface of the holding member 36 at the axially intermediate position thereof substantially abuts each other.

Further, in the illustrated embodiment, the tool mounting portion 16 is centered between the main spindle body 32 and the holding member 36 with respect to the axis 32 a of the main spindle body 32 (that is, the rotation axis of the work spindle 30). A fitting portion 80 is provided. The fitting portion 80 includes a cylindrical outer peripheral surface portion 82 formed on the spindle main body 32 adjacent to the end surface 32 c and a holding member 36 adjacent to the second locking surface 36 b. And an inner peripheral surface portion 84 provided. The outer peripheral surface portion 82 and the inner peripheral surface portion 84 are designed such that when the holding member 36 is properly mounted on the main spindle body 32, they are fitted complementarily (that is, in an intaglio style). Has shape and dimensions. Thereby, the holding member 36 is fixed in the radial direction with respect to the main spindle body 32.

In addition to this, the mounting member 66 is complementarily received in the recess 64 of the holding member 36, and the plurality of fastening elements 68 are firmly tightened, so that the mounting member 66 is radially attached to the holding member 36. Fixed to. In this way, the tool mounting section 16 is held centered on the main spindle body 32 against external forces such as cutting resistance. As a result, the plurality of tools 14 mounted on the tool mounting portion 16 have their respective cutting edges positioned at a predetermined distance from the rotation axis of the work spindle 30 (the axis 3 2 a of the spindle main body 32). Is fixedly held.

FIGS. 3A and 3B show a machine tool according to a second embodiment of the present invention. The work spindle 90 is shown. The work spindle 90 in the second embodiment has substantially the same configuration as the work spindle 30 in the above-described first embodiment, except for the configuration of the tool mounting portion. Therefore, corresponding components are denoted by common reference numerals, and description thereof is omitted.

In the work spindle 90, a holding member 36 for holding the chuck 34 in the end region 3 2b of the spindle main body 32 directly supports the tool 14 and forms a tool mounting portion 16 . The holding member 36 is provided with a keyway 92 extending in the axial direction at the rear end in the axial direction (the left end in FIG. 3A) of the inner surface thereof. Correspondingly, a key 94 is fixedly installed at a predetermined position on the outer peripheral surface in the axial front end (right end in FIG. 3A) of the main spindle body 32. The holding member 36 is attached to the main spindle body 32 by moving in the axial direction with respect to the main spindle body 32 while slidably receiving the key 94 in the key groove 92. In the illustrated embodiment, each of the holding member 36 and the main spindle body 32 has a plurality of key grooves 92 and a plurality of keys 94 at appropriate positions spaced apart in the circumferential direction.

The holding member 36 further has an annular locking surface 62 that engages with the shoulder surface 50 of the chuck 34 at the axial front end (the right end in FIG. 3A) of the inner surface thereof. An annular shoulder surface 96 substantially perpendicular to the central axis 36a is formed in the rear end region in the axial direction of the outer surface. The holding member 36 is fixed to the main spindle body 32 using an annular cap nut 98 having a center axis 98 a. The cap nut 98 has a female screw 100 in its axial rear end (left end in FIG. 3A) and a central axial line in its axial front end (right end in FIG. 3A). An annular locking surface 102 substantially perpendicular to 98a is formed. The female screw 100 is screwed into a male screw 60 provided in the axial front end region of the main spindle body 32. In addition, the locking surface 102 has a shape and dimensions capable of engaging with the shoulder surface 96 of the holding member 36. After attaching the holding member 36 to the front end of the spindle main body 32, the cap nut 98 is arranged so as to surround the rear end region in the axial direction of the holding member 36, and the female screw 10 of the cap nut 98 is arranged. 0 is screwed into the male screw 60 of the main spindle body 32. Then, the female screw 100 is tightly fastened to the male screw 60, and the retaining surface 102 of the cap nut 98 is brought into close contact with the shoulder surface 96 of the retaining member 36, thereby holding the retaining member 36. Is fixed to the spindle body 32. Further, in this state, the locking surface 62 of the holding member 36 closely abuts the shoulder surface 50 of the chuck 34, and holds the chuck 34 so as not to fall off from the operating member 52.

The holding member 36 is provided with a plurality (four in the figure) of grooves 70 arranged on the front end face in the axial direction at substantially equal intervals in the circumferential direction. Each of these grooves 70 constitutes the above-described tool holding portion 22 (FIG. 1), and each of the grooves 70 has a cutting edge protruding radially outward of the holding member 36. Is attached. That is, in this embodiment, the attachment member 66 in the above-described first embodiment is omitted.

Each groove 70 of the holding member 36 has a substantially trapezoidal outline in the end view of FIG. 3B, and the tool 14 mounted in the groove 70 partially matches the trapezoidal outline of the groove 70. It has a parallelogram outline. Therefore, each tool 14 is complementarily received in the corresponding groove 70 of the holding member 36 without play, and is fixed at a predetermined position by a fastening element 72 such as a port.

Each of the tools 14 mounted on the holding member 36 uses an indexing rotation control axis (C axis) for the workpiece, which is one of the main spindle functions of the workpiece spindle 90, and is used as a machine base (not shown). It is selectively positioned to the work position predetermined above. Here, the key groove 92 of the holding member 36 and the key 94 of the spindle main body 32 are positioning elements for mechanically positioning the tool mounting portion 16 (holding member 36) in the rotation direction of the work spindle 90. It works as On the holding member 36, the groove 70 for mounting the tool 14 and the keyway 92 The relative positional relationship is unchanged, and can be stored in advance in the control device 20 (FIG. 1) of the operating mechanism 18. Further, the position of the key 94 of the spindle main body 32 can be stored in advance in the control device 20 (FIG. 1) based on the C-axis origin of the work spindle 90. Therefore, the cutting edge position of each tool 14 attached to the holding member 36 is specified on the same axis of the work spindle 90. As a result, each tool 14 can be accurately located at the work position by the C-axis control of the control device 20.

Further, in the illustrated embodiment, the inner peripheral surface area having the key groove 92 of the holding member 36 and the outer peripheral surface area having the key 94 of the spindle main body 32 are formed by attaching the tool mounting portion 16 to the main spindle main body. It functions as a fitting portion centered with respect to the axis 32 of 32 (that is, the rotation axis of the work spindle 90). Thereby, the tool mounting portion 16 (holding member 36) is held centered on the main spindle body 32 against external force such as cutting resistance.

4A and 4B show a modification of the work spindle 90 described above. In this modification, the holding member 36 is fixed to the main spindle body 32 by using a fastening element 104 such as a bolt instead of the cap nut 98. In the illustrated embodiment, four fastening elements 104 are used which are equally spaced in the circumferential direction. According to this configuration, the tool mounting portion 16 (holding member 36) can be mechanically positioned in the rotation direction of the work spindle 90, and the tool mounting portion 16 can be more firmly fixed. It can be effectively applied to cutting work with high processing load.

FIG. 5 shows a work spindle 110 of a machine tool according to a third embodiment of the present invention. The work spindle 110 in the third embodiment has substantially the same configuration as the work spindle 30 in the above-described first embodiment except that the existing equipment can be used more effectively. Therefore, corresponding components are denoted by common reference numerals, and description thereof is omitted. In the work spindle 110, the spindle main body 32 protrudes beyond the front end face in the axial direction of the operating member 52 at its end area 3 2b, and its annular end face 3 2c and the shoulder surface of the chuck 34 are provided. And 50 are arranged on the same plane when viewed in a direction orthogonal to the axis 32a. On the other hand, the locking surface 62 of the holding member 36 has a shape and dimensions capable of uniformly engaging both the shoulder surface 50 of the chuck 34 and the end surface 32c of the spindle main body 32. .

Such a configuration of the main spindle body 32 and the holding member 36 is a general configuration in the rear main spindle of an existing automatic lathe. Therefore, in the work spindle 110, the holding member 36 can be replaced with a second (ie, existing) holding member 112 having no tool mounting portion 16. In other words, for the work spindle of the existing structure, the holding member 112 used for the work spindle is replaced with the holding member 36 constituting the tool mounting part 16 in cooperation with the mounting member 66. By simply doing so, the work spindle 110 according to the present invention can be configured. Thus, according to the work spindle 1 110

However, the number of tools that can be installed can be easily increased by making minimal structural changes such as replacing one part with an existing automatic lathe.

On the other hand, in the first and second embodiments described above, the spindle main body and the holding member used for the work spindle of the existing structure are replaced with the spindle main body 32 and the holding member 36. For example, the work spindles 30 and 90 according to the present invention can be configured. Even with such a configuration, the number of mountable tools can be increased with a relatively small structural change compared to existing automatic lathes.

The work spindle 110 has a cylindrical outer peripheral surface portion 8 2 formed on the spindle main body 32 adjacent to the end face 32 c similarly to the fitting portion 80 of the work spindle 30 described above. And an inner peripheral surface portion 84 provided on the holding member 36 adjacent to the locking surface 62. The tool mounting portion 16 is connected to the axis 32a of the spindle main body 32 (that is, the work spindle 11). Centering about 0 axis of rotation) It functions as a fitting part 80 that performs the fitting. Also, as a preparatory work, the cutting edge of one tool 14 is set in advance on the machine base so that the multiple tools 14 attached to the tool mounting part 16 can be accurately indexed to the working position. The position of the cutting edge of each tool 14 on the C-axis of the work spindle 110 can also be specified by contacting the reference stationary surface 7 8 (Fig. The same is true.

FIG. 6 shows a modification of the work spindle 110 described above. In this modification, the attachment member 66 is omitted, and the tool 14 is directly mounted in the groove 70 provided in the holding member 36. In this case as well, the present invention can be implemented simply by replacing the holding member 112 (FIG. 5) used for the work spindle of the existing structure with the holding member 36 forming the tool mounting part 16. Such a work spindle 110 can be configured.

The work spindles 30, 90, 110 in the various embodiments described above serve as the back spindle of the automatic lathe, and the workpiece W (FIG. 1) is gripped by the chuck 34, and the operation mechanism 18 Under the control of the controller 20 (FIG. 1), the main operations such as high-speed rotation, indexing rotation, and cutting feed can be performed. Further, these work spindles 30, 90, and 110 serve as a tool rest of the tool 14 attached to the tool attachment portion 16 as well as rotate at high speed under the control of the control device 20 (FIG. 1). It can perform the main operations such as run-out rotation, cutting feed, etc., and the workpiece W (Fig. 1) gripped by the front spindle (second workpiece spindle) of the automatic lathe and various tools depending on the desired tool 14 Can be cut.

For example, the control device 20 rotates the front spindle (second workpiece spindle) at a high speed while rotating the workpiece spindle 30, 90, 110 with the front spindle along the X axis and the Z axis. By performing a feed operation, the workpiece W 1 (FIG. 1) gripped by the front spindle can be turned by the tool 14 attached to the tool attachment portion 16. In this case, the tool mounting part 1 6 As the plurality of tools 14 to be attached to the cutting tool, various throw-away tips II attached to the tip of a known cutting tool, and various pipes can be selected if the dimensions are allowed.

Further, the control device 20 moves the work spindles 30, 90, 110 and the front spindle along the X axis and the Z axis while continuously rotating the work spindles 30, 90, 110 at a high speed. The workpiece W ′ (FIG. 1) gripped on the front spindle can be milled by the tool 14 attached to the tool mounting section 16 by relatively moving the workpiece. In this case, the plurality of tools 14 attached to the tool attachment portion 16 are all the same as shown in the figure, and a throw-away tip attached to the tip of a known cutting tool can be selected.

Further, the control device 20 synchronizes the work spindles 30, 90, 110 with the front spindle at a predetermined speed while continuously rotating the work spindles 30, 90, 110 with the front spindle. The spindle and the spindle are moved relatively along the X and Z axes, and the workpiece W (Fig. 1) gripped by the front spindle is moved to the polygon by the tool 14 attached to the tool attachment section 16 Can be processed. Also in this case, the plurality of tools 14 attached to the tool attachment portion 16 are all the same as shown in the figure, and a sloppy tip attached to the tip of a known cutting tool can be selected.

As described above, the operation required for the work spindles 30, 90, and 110 as the tool post in each embodiment is the same as the operation as the original back spindle, and therefore, the operation is already installed on the automatic lathe. The operating mechanism 18 (including hardware and software) can be used without modification. In other words, the work spindles 30, 90, 110 can be used as a tool post without impairing the original back spindle function. Therefore, without complicating the mechanical structure and operation control of the automatic lathe or increasing the overall dimensions, the tool post in the automatic lathe can be fully used. The number of tools that can be mounted in advance as a body can be increased. The indexing operation of the tool 14 on the work spindles 30, 90, and 110 as a tool post is performed under the control of the C-axis of a servo motor (not shown) equipped as one of the spindle functions. This has the advantage that the time required for tool selection can be effectively reduced. In addition, when the work spindles 30, 90, and 110 are equipped with a C-axis angle detector as one of the spindle functions, the indexing position can be easily corrected and the tool can be mounted. The total number of tools 14 that can be mounted on the part 16 can be easily increased. In addition, when the tool 14 attached to the tool mounting part 16 is a throw-away chip, the main spindle body 32 functions as, for example, a shank of a pipe, so the rigidity of the tool as a whole is considered. Is improved. Also, when replacing the tool 14 to be mounted on the tool mounting section 16, prepare a plurality of tool mounting sections 16 (holding members 36, mounting members 66) with different tools 14 mounted in advance. In addition, if the entire tool mounting portion 16 is replaced, the time and labor required for setup change can be reduced despite the increase in the number of tools that can be mounted on the turret.

FIG. 7 shows an example of the layout of the work spindle and the tool rest of the machine tool according to the present invention. This example relates to an NC lathe. The main front spindle 120, which grips and rotates the workpiece supplied from the outside of the lathe, and coaxially opposes the front main spindle 120 in the axial direction. The auxiliary back spindle 1 2 2 that grips and rotates the partially machined workpiece passed from the front spindle 1 220 and multiple tools 1 2 4 and 1 2 6 respectively The first and second turrets 1 28, 130 are provided and independently operated, and the third turret 13 2 is provided with a plurality of tools 1 26 and fixedly arranged.

The front spindle 120 is configured to move linearly along a feed control axis (Z1 axis) parallel to its own axis of rotation 120a. More positive The surface spindle 120 is a rotary indexing control axis (C 1) that performs high-speed rotary motion for turning, which is the main function, and rotary indexing rotation for cutting, such as milling, which is a supplementary function. Axis). Therefore, the front spindle 120 is moved to a desired position on the end face or the outer peripheral face of the workpiece to be gripped by its own chuck by the rotation indexing motion under the control of the C1 axis. It enables a variety of machining using the rotary tools mounted on the tool post 1 28, 130. In addition, a guide bush as an auxiliary support device is provided at a predetermined position in front of the front spindle 120 in the axial direction to support the workpiece gripped by the front spindle 120 in the vicinity of a portion to be machined at the tip thereof. Thread 134 is installed coaxially with front spindle 120.

The first turret 1 2 8 is arranged in front of the main spindle 120 in the axial direction, close to the side of the guide bush 134, and is a feed control axis orthogonal to the Z 1 axis of the front main spindle 120. (XI axis) and linearly move along the feed control axis (Y1 axis) orthogonal to both Z1 axis and X1 axis. The first turret 1 28 is a so-called comb turret that holds a plurality of tools 1 2 4 and 1 2 6 in a parallel arrangement, and is a turning tool such as a pile and a rotary tool such as a drill and a milling cutter. Can be equipped so that it can be positioned orthogonally to the rotation axis 120a of the front main shaft 120. The first turret 1 2 8 basically has its own X 1 axis movement and front spindle on the cutting edge of the desired tool 1 2 4 and 1 2 6 selected by its own Y 1 axis movement. By cooperating with the Z1 axis movement of 120, interpolation operation can be performed according to the NC program, and as a result, the desired workpiece can be cut into the workpiece held by the front spindle 120. Is applied. Note that the Y1 axis movement of the first tool post 1 2 8 is not only a tool selection operation, but also, for example, when a rotary tool is selected, a cutting (D-cut) operation on the outer peripheral surface of the workpiece. Also works.

The second turret 130 is the first turret across the guide bush 1 34 A straight line along the feed control axis (X 2 axis) orthogonal to the Z 1 axis of the main spindle 1 2 0 and the feed control axis (Z 2 axis) parallel to the Z 1 axis. Configured to move. The second turret 130 is a so-called turret turret that holds a plurality of tools 124, 126 at equal intervals in the circumferential direction. The rotary indexing control axis (TI Axis) and equipped with turning tools such as piles, and rotating tools such as drills and milling cutters that can be positioned orthogonally or parallel to the rotation axis 120a of the front spindle 120. it can. Turret 2 130 basically has its own X 2 axis movement and Z 2 axis movement on the cutting edge of the desired tool 12 4, 12 6 indexed by its own TI axis rotation. With the cooperation of the above, the interpolation operation can be performed according to the NC program, whereby the workpiece to be gripped by the front spindle 120 or the rear spindle 122 is subjected to the desired cutting. You.

The back spindle 1 2 2 has a rotation axis 1 2 2 a parallel to the rotation axis 1 2 0 a of the front spindle 1 2 0, and a guide bush 1 3 4 is sandwiched in front of the front spindle 1 2 0 in the axial direction. The feed is orthogonal to the Z1 axis of the front main spindle 120. It moves linearly along the U control axis (X3 axis) and the feed control axis (Z3 axis) parallel to the Z1 axis. It is configured to In addition, the back main spindle 1 2 2 uses a rotary indexing control axis (C 2 Axis). Therefore, the back spindle 122 is moved to the desired position on the end face or the outer peripheral surface of the workpiece gripped by its own chuck by the rotation indexing movement under the control of the C2 axis, and the first to third spindles are rotated. The tool post 1 28, 1 30 and 1 32 can be used to perform a variety of machining using the rotating tools.

The third turret 1 32 has a comb-type turret configuration that holds a plurality of tools 1 2 6 in a parallel arrangement, and mainly boring pipes, drills, and ends. Equipped with a drilling tool such as a mill so that it can be positioned parallel to the rotation axis 1 2 2 a of the rear spindle 1 2 2, and is arranged opposite the X 3 axis movement path of the rear spindle 1 2 2 .

The back spindle 1 2 2 basically selects the desired tool 1 2 6 on the third turret 1 3 2 by its own X 3 axis movement, as well as its own X 3 axis movement and Z 3 axis In cooperation with the movement, it is possible to cause the cutting edge of the tool 1 26 to perform a relative interpolation operation in accordance with the NC program, thereby being transferred from the front spindle 120 to the rear spindle 122. The desired material is subjected to the desired cutting.

As described above, the NC lathe described above controls the operation of each of the spindles 120 and 122 and each of the turrets 1 and 8 and 130 along a number of control axes, so that three NC lathes are provided. Using the desired tool 1 2 4 and 1 2 6 selected on the turret 1 2 8 1 3 0 and 1 3 2, the workpiece to be gripped by both spindles 1 2 0 and 1 2 2 Can be processed automatically. In an NC lathe having such a configuration, if the tool spindle 14 is mounted on the rear spindle 12 2 with the tool mounting section 16 in the above-described various embodiments, the number of tools that can be mounted as a tool post as a whole can be easily increased. The tool change operation can be simplified.

Next, an example of a material processing method according to the present invention will be described with reference to FIGS. 8A and 8B. This machining example can be carried out by an NC lathe having the layout example of FIG. 7 in which the work spindle 30 shown in FIG. 2A is applied to the back spindle 122.

First, as a preparatory stage, a plurality of tools 14 required for machining are attached to the tool mounting part 16 of the work spindle 30 that constitutes the back spindle 1 2 2 (first work spindle) in Fig. 7. The workpiece W is gripped by the front spindle 120 (second spindle) in FIG. 7, and the desired length of the tip of the workpiece W is extended from the guide push 13 4 (FIG. 8). A) Then, ヮ Work spindle 30 is indexed, and the selected desired tool 14 is positioned at work position P. Then, guide the work spindle 30 to the guide bush 1

Feed operation is performed to 3 4 (and the main spindle 12 0), and the workpiece W is cut by the selected tool 14:!: (FIG. 8B).

In the above machining example, in order to allow the work spindle 30 to continue to perform the original back spindle function smoothly, chips and cutting oil are removed inside the chuck 34 of the work spindle 30 during cutting. It is necessary to prevent intrusion. Regarding this requirement, the work spindle 30 constituting the back spindle 122 generally has a discharge mechanism 140 for discharging a workpiece (not shown) held by the chuck 34. Therefore, the control device 20 of the operating mechanism 18 (FIG. 1) controls the feed operation required for the above-described cutting while the discharge mechanism 140 is in the discharge operation. This can prevent chips and cutting oil from entering the chuck 34.

Specifically, the ejection mechanism 140 can have a knockout pin 142 that mechanically pushes a workpiece (not shown) gripped by the chuck 34 from the rear in the axial direction to the front ( (Figure 8B). In this case, the control device 20 applies the knockout pin 14 2 to the grip portion of the chuck 34.

Controls the above-mentioned feeding operation while inserted in 42. At this time, the knockout pin 144 may be gripped by the chuck 34. The knockout pins 144 are connected to a drive source such as a cylinder device.

(Not shown).

Further, the discharge mechanism 144 may have a compressed air discharging device 144 for pushing out a workpiece (not shown) held by the chuck 34 with compressed air (FIG. 8B). The compressed air discharging device 144 includes a compressed air supply source 144 a and an air passage 144 b provided inside the knockout pin 142. In this case, the controller 20 The feed operation is controlled while the compressed air is blown out from the knockout pin 142 to the area of the chuck 34 by operating the air supply source 144a.

Next, another example of the material processing method according to the present invention will be described with reference to FIGS. 9A to 9D. This machining example can also be performed by an NC lathe having the layout example of FIG. 7 in which the work spindle 30 shown in FIG. 2A is applied to the back spindle 122.

First, in the same manner as in the preparation stage described with reference to FIG. 8A, a plurality of tools 14 required for processing are attached to the tool mounting portion 16 of the work spindle 30 constituting the rear spindle 12 2 (FIG. 7). On the other hand, the workpiece W is gripped by the front spindle 120 (FIG. 7), and the desired length of the tip of the workpiece W is extended from the guide bush 134. Then, the desired cutting force p is applied to the workpiece w by using the desired tools 12 4 and 12 6 mounted on the first and second tool rests 1 28 and 130 shown in FIG. .

When the processing on the front spindle side is completed, the work spindle 30 functions as the original back spindle, and the tip end of the workpiece W is gripped by the chuck 34. In this state, the work spindle 30 and the front spindle 120 (FIG. 7) are rotated at a high speed in synchronization with each other, for example, by a parting tool 144 attached to the first turret 128 (FIG. 7). The workpiece W is cut at a predetermined position (Fig. 9A). During this time, the discharge mechanism 140 is in a non-operating state, and the knockout bin 142 is drawn into the work spindle 30.

The workpiece spindle 30 holding the partially processed workpiece W on the chuck 34 is once separated from the guide bush 134. In the meantime, a predetermined length of the tip of the succeeding workpiece W, which is gripped by the front main spindle 120 (FIG. 7), is extended by the guide bush 134. Therefore, the workpiece W is held in the chuck 34 by the tool post function of the peak spindle 30. The work spindle 30 is indexed while holding the tool, and the selected desired tool 14 is positioned at the work position P. Then, the workpiece spindle 30 is fed with respect to the guide bush 134 to cut the workpiece W by the selected tool 14 (FIG. 9B).

As described above, in this machining example, the control device 20 (FIG. 1) of the operating mechanism 18 controls the feed operation required for the above-described cutting while holding the workpiece W on the work spindle 30. I do. This prevents chips and cutting oil from entering the inside of the chuck 34 of the work spindle 30 during cutting.

Subsequently, the work spindle 30 is again made to function as a back spindle, and for example, the desired tool 12 6 mounted on the third tool rest 13 2 of the NC lathe shown in FIG. A desired cutting process is performed on the gripped workpiece W (Fig. 9C). Then, at the stage where the machining on the back spindle has been completed and the cutting of the workpiece W has been completed, the work spindle 30 is brought close to a predetermined collection box 148, the chuck 34 is opened, and the chuck is opened. The workpiece W is discharged to the collection box 148 by the operation of the lockout pin 144 (FIG. 9D).

As described above, according to the material processing method of the present invention, since the tool is attached to the work spindle, the workpiece can be mounted in spite of an increase in the number of mountable tools as the total tool post of the machine tool. The original back side of the spindle With the same operation control as the operation control of the spindle, the workpiece can be machined with the desired tool. Also, as in the machining examples shown in Figs. 9A to 9D, in a series of machining programs, the work spindle equipped with the tool is designed to continuously perform its spindle function and turret function. It can be operated. Therefore, according to the machine tool and the material processing method of the present invention, it is possible to switch between the spindle function and the tool rest function of the work spindle having the tool mounting portion at a desired time without requiring an artificial switching operation. You can.

Although the present invention has been described with reference to the preferred embodiments, it will be appreciated by those skilled in the art that various modifications and changes can be made without departing from the spirit and scope of the claims described below. You will understand. For example, Figure

If the guide bush 1 34 is omitted in the example of the layout shown in Fig. 7, a tool mounting part 16 is provided on the front main spindle 120 in addition to or instead of the rear main spindle 122. 14 can also be attached. In addition to a plurality of work spindles arranged in parallel with each other and a plurality of work spindles arranged orthogonally to each other as well as a machine having a pair of work spindles arranged opposite to each other as shown in the figure. In a conventional machine tool, a tool can be mounted by equipping a desired work spindle with a tool mounting portion. In either case, the work spindle equipped with the tool mounting part can be used as a tool post in addition to the original spindle function, so the total number of tools that can be installed as a tool post total can be increased.

Claims

The scope of the claims

1. A machine tool,

A work spindle that can hold and rotate the workpiece,

A tool mounting portion which is installed on the work spindle so as to be operable with the work spindle and on which a tool is mounted;

An operating mechanism for operating the work spindle;

Machine tool equipped with

2. The machine tool according to claim 1, wherein the operation mechanism includes a control device for indexing and rotating the work spindle to position a tool attached to the tool attachment portion at a predetermined work position.

3. The tool mounting portion has a plurality of tool holding portions which are spaced apart in a circumferential direction around a rotation axis of the work spindle, and the control device includes a plurality of tool holding portions mounted on the plurality of tool holding portions. 3. The machine tool according to claim 2, wherein each of the tools is selectively positioned at the working position.

4. The machine tool according to claim 1, wherein the operation mechanism includes a control device that causes a tool attached to the tool attachment portion to perform a cutting operation on a workpiece.

5. The machine tool according to claim 4, wherein the control device controls the cutting operation in a state where another workpiece is gripped by the work spindle.

6. The work spindle includes a discharge mechanism that discharges a workpiece gripped by the work spindle, and the control device controls the cutting operation in a state where the discharge mechanism performs a discharge operation. Machine tool according to item 4

7. The machine tool according to claim 6, wherein the discharge mechanism has a knock bin.

8. The method according to claim 6, wherein the discharge mechanism has a compressed air discharging device. Machine Tools.

9. The work spindle includes a hollow cylindrical spindle main body, a chuck installed in an end region of the spindle main body, and a holding member for holding the chuck in the end region of the spindle main body. The machine tool according to claim 1, wherein the tool attachment portion is provided on a holding member.

10. The machine tool according to claim 9, wherein a positioning element for positioning the tool mounting portion in a rotation direction of the work spindle is provided between the spindle main body and the holding member.

11. The machine tool according to claim 9, wherein a fitting portion that centers the tool mounting portion with respect to the rotation axis of the work spindle is provided between the spindle main body and the holding member.

12. The machine tool according to claim 9, wherein the holding member is replaceable with a second holding member having no tool mounting portion.

13. The machine tool according to claim 1, wherein the tool attached to the tool attachment portion is a throw-away chip.

14. The apparatus further comprises a rotatable second work spindle separate from the work spindle, and the operating mechanism attaches the workpiece gripped by the second work spindle to the tool mounting portion. The machine tool according to claim 1, wherein the tool performs a cutting operation.

15. The work spindle having the tool mounting portion is a back spindle that can rotate while gripping a partially-processed workpiece delivered from the second workpiece spindle. The machine tool according to 4.

16. The control device rotates the second work spindle, and causes a tool attached to the tool attachment section to perform a turning operation on the workpiece gripped by the second work spindle. The machine tool described in 4.

17. The control device rotates the work spindle having the tool mounting portion, and applies the second key to the tool mounted on the tool mounting portion. 15. The machine tool according to claim 14, wherein the work material gripped by the spindle is milled.

18. The control device may rotate the work spindle having the tool attachment portion and the second work spindle in synchronization with each other, and attach the tool attached to the tool attachment portion to the second work spindle. 15. The machine tool according to claim 14, wherein the gripped workpiece is polygonally processed.

1 9. A material processing method for a machine tool having a plurality of workpiece spindles separated from each other,

Attach a tool to the first workpiece spindle,

The workpiece is gripped by the second spindle,

Operating the first and second work spindles to process the workpiece by the tool;

Material processing method.

20. The material processing method according to claim 19, wherein the first work spindle is operated so as to continuously perform a spindle function and a tool rest function in a machining program.