JP7441678B2 - Rotary tool equipment and machine tools - Google Patents

Description

The present invention relates to a rotary tool device and a machine tool.

As a conventional machine tool, Patent Document 1 discloses a rotary tool device in which a plurality of spindle axes are arranged in the horizontal direction, and machining is performed by adjusting the direction of the cutting edges of the plurality of rotary tools with respect to the axis of the workpiece. It will be done.

JP 2019-181653 Publication

In the machine tool disclosed in Patent Document 1, due to space constraints, the rotary tool device drives a plurality of spindle shafts by combining one motor and a gear mechanism to drive a plurality of rotary tools. For this reason, displacement due to backlash and heat generation and vibration from spindle shafts other than the processing spindle shafts rotating simultaneously are transmitted to the spindle shaft, making it impossible to perform highly accurate processing. The same applies when combining one motor and a belt mechanism.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a rotary tool device and a machine tool that can perform highly accurate machining.

In order to achieve the above object, a rotary tool device according to a first aspect of the present invention includes:
a tool holder that holds a rotary tool for machining a workpiece held by a spindle;
a spindle shaft formed such that the tool holding portion can be attached to the tip;
a motor having an output shaft directly connected to a base end of the spindle shaft and rotating the spindle shaft together with the tool holding portion;
one casing that supports the motor, accommodates a plurality of spindle shafts arranged parallel to each other, and rotatably accommodates the spindle shafts;
A plurality of the motors are provided on each of the plurality of spindle shafts with specifications according to the rotary tool ,
The cutting edge of the rotary tool is brought into contact with the workpiece and processed by relative movement between the axial direction of the workpiece held by the main shaft and the plurality of axial directions of the rotary tool,
Rotary tool equipment.

In order to achieve the above object, a machine tool according to a second aspect of the present invention includes:
a rotary tool device;
The main shaft rotatably holds the workpiece.

According to the present invention, highly accurate processing can be performed.

1 is a schematic plan view of a machine tool according to an embodiment of the present invention. 1 is a schematic front partial sectional view of a machine tool according to an embodiment of the present invention. 1 is a schematic side view of a machine tool according to an embodiment of the present invention. FIG. 1 is an enlarged partial cross-sectional view of a rotary tool device according to an embodiment of the present invention.

A rotary tool device and a machine tool according to an embodiment of the present invention will be described with reference to the drawings. In the following explanation, the vertical direction is referred to as the "Y-axis direction," the horizontal direction along the center line of the workpiece is referred to as the "Z-axis direction," and the horizontal direction perpendicular to the Y-axis and Z-axis directions is referred to as the "X-axis direction." ”.

As shown in FIGS. 1 and 2, the machine tool 1 is configured, for example, as an NC (Numerical Control) lathe that processes a workpiece. The machine tool 1 includes a bed S, which is the base of the entire machine tool 1, a spindle unit 10, a Z-axis moving mechanism 20, a tool mechanism 30, a rotary tool device 50, and a control unit 90 that controls the machine tool 1. , is provided.

(Spindle unit 10)
As shown in FIGS. 1 and 2, the spindle unit 10 is a mechanism for processing the front surface (the surface facing the +Z side) and the side surface of the workpiece. The spindle unit 10 includes a spindle 11 that rotatably holds a workpiece, and a headstock 12 that rotatably supports the spindle 11. The main shaft 11 is equipped with a chuck at its tip for holding a workpiece. The headstock 12 has a built-in spindle rotation motor (not shown) that rotates the workpiece held by the chuck. The spindle unit 10 includes a Z-axis moving mechanism 20 that moves the spindle stock 12 in the Z-axis direction.

As shown in FIG. 1, in the Z-axis moving mechanism 20, a rail 21 is attached to the bed S along the Z-axis direction, and the headstock 12 is movable along the rail 21. The Z-axis moving mechanism 20 moves the headstock 12 together with the nut 12a (see FIG. 2) in the Z-axis direction by rotating the ball screw 21a using the Z-axis motor 21b. As a result, the main shaft 11 moves relative to the bed S in the Z-axis direction.

(Tool mechanism 30)
As shown in FIGS. 1 and 2, the tool mechanism 30 is a mechanism that moves tools 31a and 32a of tool units 31 and 32 in the X-axis direction and the Y-axis direction with respect to the workpiece gripped by the spindle unit 10. .

The tool mechanism 30 includes a fixed base 41 fixed to the bed S, tool units 31 and 32, an X-axis moving mechanism 33 that moves the tool units 31 and 32 in the It includes a Y-axis moving mechanism 34 that moves in the Y-axis direction along the Y-axis direction, and a guide bush device 80 that is fixed to the fixed base 41.

As shown in FIGS. 1 and 2, the fixing base 41 has a cavity 41a that penetrates in a direction along the central axis A of the main shaft 11.
The fixed base 41 is provided with an X-axis moving mechanism 33 and a Y-axis moving mechanism 34 via the X-axis moving mechanism 33. Like the Z-axis moving mechanism 20, the X-axis moving mechanism 33 and the Y-axis moving mechanism 34 are configured by a motor, a ball screw, and a nut.

As shown in FIGS. 2 and 3, the tool units 31 and 32 are arranged on the left and right sides of the Y-axis moving mechanism 34 in FIG. The tool units 31 and 32 are positioned so as to sandwich the workpiece held by the main spindle 11 from both sides in the X-axis direction. The tool units 31 and 32 include a plurality of tools 31a and 32a, and tool rests 31b and 32b that hold the plurality of tools 31a and 32a along the X-axis direction. A plurality of tools 31a, 32a are provided in the tool rests 31b, 32b, arranged in a comb shape in the Y-axis direction. Each of the tools 31a and 32a is composed of, for example, a cutting tool.

Under the control of the control unit 90, the Z-axis moving mechanism 20, the X-axis moving mechanism 33, or the Y-axis moving mechanism 34 moves the tools 31a and 32a relative to the axis (Z-axis direction) of the workpiece rotated by the main shaft 11. Workpieces are processed by moving them so that they face in the intersecting directions.

A guide bush device 80 is arranged in the cavity 41a of the fixed base 41. The guide bush device 80 assists in holding and moving the workpiece as the main shaft 11 moves. The guide bush device 80 can be changed as appropriate depending on the workpiece to be processed.

(Rotary tool device 50)
As shown in FIGS. 1, 3, and 4, the rotary tool device 50 is provided in the Y-axis moving mechanism 34 below the tool unit 31, and processes a workpiece using a rotary tool 51 that rotates itself. The rotary tool 51 is composed of, for example, a drill, a tap, a milling cutter, or the like.

The rotary tool device 50 includes a tool holder 52 that holds a rotary tool 51 for machining a workpiece held by the main spindle 11, a spindle shaft 53 on which the tool holder 52 can be attached to a tip 53a, and a spindle shaft 53. A tool rotation motor (motor) 54 is directly connected to the base end 53b of the rotary tool 51 and rotates the spindle shaft 53 along with the tool holder 52. The casing 55 accommodates the spindle shaft 53 in a rotatable manner so as to face a direction intersecting the central axis (axis of the workpiece) A of the main shaft 11 held by the main shaft 11 .

In the rotary tool device 50, a housing 55 is fixed below the tool unit 31 of the Y-axis moving mechanism 34. In the housing 55, a spindle shaft 53 is arranged parallel to the horizontal direction along the X-axis direction, and a plurality of (in the illustrated example, two) spindle shafts 53 are arranged in the Y-axis direction (vertical direction). . Thereby, the cutting edge of the rotary tool 51 attached to the housing 55 is arranged so as to face the direction (X-axis direction) perpendicular to the central axis A of the main shaft 11.

Each spindle shaft 53 is rotatably supported by a housing 55. A plurality of bearings 55a are provided in the housing 55 at intervals in the X-axis direction. In each spindle shaft 53, a plurality of bearings 55a support vibration of the central axis of the spindle shaft 53, rotational load and thrust load accompanying machining.

A tool holder 52 is detachably attached to the tip 53a of each spindle shaft 53, and the rotary tool 51 is fixed to the tool holder 52. The tool holder 52 and the rotary tool 51 constitute one tool unit. One of the plurality of types of tool units is selectively attached to the tip 53a of the spindle shaft 53.

As shown in FIG. 4, a motor output shaft 54a of a tool rotation motor 54 is directly connected to a base end 53b of each spindle shaft 53 via a connection coupling 54b. The base end 53b of the spindle shaft 53 has a cylindrical shape with a smaller diameter than the main body of the spindle shaft 53. The motor output shaft 54a has a cylindrical shape with the same diameter as the base end 53b of the spindle shaft 53. The coupling coupling 54b has a cylindrical shape. A base end 53b of the spindle shaft 53 is fixed inside one end of the coupling coupling 54b, and a motor output shaft 54a is fixed inside the other end of the coupling coupling 54b. That is, the same number of tool rotation motors 54 are prepared according to the number of spindle shafts 53, and the tool rotation motors 54 are directly connected to the spindle shafts 53 through only the coupling coupling 54b without using a driving force transmission mechanism such as a gear mechanism or a belt mechanism. to drive. As a result, together with the tool holder 52, the mounted rotary tool 51 is rotated by an independent tool rotation motor 54.

The tool rotation motor 54 is preferably a small motor in order to secure mounting space to the housing 55, and an AC motor or a DC motor such as a synchronous motor or an induction motor is used depending on the rotary tool 51.
Furthermore, since each spindle shaft 53 is provided with an independent tool rotation motor 54, each motor may have different specifications, and motors with different rotational speeds and outputs may be selected as appropriate depending on the rotary tool 51 to be used. and set it up. The tool rotation motor 54 can also be configured with, for example, one with a rotation speed of 5,000 rpm and one with a high-speed rotation of 20,000 rpm.

In such a rotary tool device 50, the tool rotation motor 54 that rotates the rotary tool 51 is directly connected to each spindle shaft 53 as an independent motor, so each tool rotation motor 54 can be made compact. Therefore, the rotary tool device 50 itself can be made compact. In addition, since a drive force transmission mechanism such as a gear mechanism or a belt mechanism is not used, backlash and vibration transmission can be suppressed and highly accurate machining can be performed. Further, the rotary tools 51 other than the rotary tool 51 used for machining can be kept stopped, and high-precision machining can be performed without the effects of vibration or heat generation. In addition, when driving multiple rotary tools 51 with one motor, the rotation speed is regulated by a gear mechanism or a belt mechanism using a belt and a pulley, making it nearly impossible to change the rotation speed. By using the rotary tool motor 54 that corresponds to the tool 51, it is possible to select the number of rotations, and it is also possible to expand the workable range.

As described above, the rotary tool device 50 is configured to be movable in the X-axis direction and the Y-axis direction by fixing the housing 55 to the Y-axis moving mechanism 34. It is also possible to provide a rotational position adjusting section (not shown) having a rotating shaft for rotating the casing 55 around a vertical axis, for example. This allows the rotating tool 51 to be oriented in a direction that intersects the central axis A of the main spindle 11 (the axis of the workpiece) and the direction in which the rotating tool 51 extends (direction of the central axis of the spindle shaft 53) (e.g., a vertical axis parallel to the Y axis). The housing 55 can be rotated around the rotation axis (direction), and the direction of the cutting edge of the rotary tool 51 can be adjusted by rotating it on a horizontal plane formed by the X-axis and the Z-axis. Thereby, the range that can be processed by the rotary tool device 50 can be expanded.

(Control unit 90)
The control unit 90 controls the entire machine tool 1, and includes a ROM (Read Only Memory), a RAM (Random Access Memory), and a CPU (Central Processing Unit). Note that the control unit 90 is schematically shown in FIG. 1 and the like.

The control section 90 numerically controls each section according to an NC (Numerical Control) program supplied from an operation section (not shown). The control unit 90 controls the main spindle 11, the Z-axis moving mechanism 20, the tool mechanism 30, the X-axis moving mechanism 33, the Y-axis moving mechanism 34, and the rotary tool device 50 through numerical control.

Next, an example of machining a workpiece by the machine tool 1 will be described.
In machining by the tool mechanism 30, under numerical control by the control unit 90, as shown in FIGS. , 32a are brought into contact with the workpiece, and the workpiece is sent in the Z-axis direction via the Z-axis moving mechanism 20. As a result, the workpiece is processed.

In machining using the rotary tool device 50, under numerical control by the control unit 90, as shown in FIGS. , the tool rotation motor 54 of only the rotary tool 51 used for machining by the rotary tool device 50 is rotated, the cutting edge of the rotary tool 51 is brought into contact with the workpiece, and the Z-axis moving mechanism 20, the X-axis moving mechanism 33, and the Y-axis moving mechanism 34 combines the feeding of the workpiece in the Z-axis direction and the movement of the rotary tool 51 in the X-axis and Y-axis directions. As a result, the workpiece is processed by the rotary tool 51.
In machining using the rotary tool device 50, the rotary tool 51 used is a drill, tap, milling cutter, or the like.

The machining by the tool mechanism 30 and the machining by the rotary tool device 50 may be performed in combination as a first machining and a subsequent second machining, or each may be performed as independent machining. When the machining is completed, the workpiece is dropped into a chute (not shown) and the machined workpiece is discharged from the machine tool 1. In this manner, the workpiece is processed by the machine tool 1.

(effect)
According to the embodiment described above, the following effects are achieved.
(1) The rotary tool device 50 includes a tool holder 52 that holds a rotary tool 51 that processes a workpiece held by the main spindle 11, a spindle shaft 53 that is formed on a tip 53a so that the tool holder 52 can be attached, A tool rotation motor (motor) 54 that is directly connected to the base end 53b of the spindle shaft 53 and rotates the spindle shaft 53 together with the tool holder 52; The casing 55 accommodates the spindle shaft 53 in a rotatable manner so as to face a direction intersecting the central axis (axis of the workpiece) A of the main shaft 11 held by the main shaft 11.
According to this configuration, the tool rotation motor 54 is directly connected to the base end 53b of the spindle shaft 53 on which the rotary tool 51 is held at the tip 53a, so that the rotary tool 51 can be rotated through the gear mechanism or the belt mechanism. Machining can be performed with the rotary tool 51 while suppressing the effects of backlash, vibration, heat generation, etc. that occur when the shaft rotates. Thereby, highly accurate machining can be performed, and machining such as polygon machining and gear machining that is performed in synchronization with the rotation of the main shaft 11 can also be performed with high precision. Further, since no gear mechanism or belt mechanism is used, the rotary tool device 50 can be made compact.

(2) The plurality of spindle shafts 53 are housed in one housing 55 in a state in which they are arranged parallel to each other, and a plurality of tool rotation motors 54 are provided for each of the plurality of spindle shafts 53. It will be done.
According to this configuration, by driving each spindle shaft 53 with an independent tool rotation motor 54, the tool rotation motors 54 other than the rotary tool 51 used for machining can be stopped, and the tool rotation motors 54 other than the rotary tool 51 used for machining can be stopped. There is no influence of vibration or heat generation from sources other than the rotary tool 51, and highly accurate machining is possible. Moreover, the tool rotation motor 54 can be made into a small motor depending on the rotary tool 51, and the rotary tool device 50 can be made compact. Further, the tool rotation motor 54 can have different specifications depending on the rotary tool 51, and high-precision machining can be performed with an appropriate specification.

(3) The machine tool 1 includes a rotary tool device 50 and a main shaft 11 that rotatably holds a workpiece.
According to this configuration, the tool rotation motor 54 is directly connected to the base end 53b of the spindle shaft 53 on which the rotary tool 51 is held at the tip 53a, so that the rotary tool 51 can be rotated through the gear mechanism or the belt mechanism. Machining can be performed with the rotary tool 51 while suppressing the effects of backlash, vibration, heat generation, etc. that occur when the shaft rotates. Thereby, highly accurate machining can be performed, and machining such as polygon machining and gear machining that is performed in synchronization with the rotation of the main shaft 11 can also be performed with high precision. Further, since no gear mechanism or belt mechanism is used, the rotary tool device 50 can be made compact, and the machine tool 1 can also be made compact. Thereby, highly accurate workpiece machining can be realized.

Note that the present invention is not limited to the above embodiments and drawings. It is possible to make changes (including deletion of constituent elements) as appropriate without changing the gist of the present invention. An example of the modification will be described below.

(Modified example)
In the above embodiment, the machine tool 1 is configured so that the workpiece held by the spindle 11 is machined by the rotary tool 51 of the rotary tool device 50. may be provided. Thereby, in addition to machining the front side of the workpiece with the main spindle 11, the back side of the workpiece can be processed with the rotary tool device 50 by transferring the workpiece to the second main spindle.

In the above embodiment, the machine tool 1 is provided with the guide bush device 80 to assist in holding and moving the workpiece as the spindle 11 moves, but the spindle 11 does not move and there is no need to support the workpiece. In some cases, the guide bush device 80 may be replaced with a guide bushless cover. The guide bushless cover is disposed in the cavity 41a of the fixed base 41 so as not to come into contact with the workpiece.
In this way, even if the machine tool 1 is provided with a guide bushless cover, machining can be performed with the rotary tool device 50 in the same manner as in the above embodiment, and the same effects can be achieved.

In the above embodiment, the machine tool 1 was equipped with the tool mechanism 30 including the tool units 31 and 32 together with the rotary tool device 50, but instead of the tool mechanism 30 or together with the tool mechanism 30, an example of the tool unit It may also be equipped with a turret device. A plurality of tools are replaceably installed on a turret that rotates around a rotation axis, and the turret is rotated to select and process a plurality of tools. In this way, even when the machine tool 1 is provided with the turret device, machining is performed by the rotary tool device 50 in the same manner as in the above embodiment, and the same effects can be achieved.

The machine tool 1 in the embodiment described above only needs to include at least the rotary tool device 50, and one or both of the tool mechanisms 30 may be omitted.

In the embodiment described above, at least part of the work performed by the operator using the operating section of the machine tool 1 may be performed by a working robot under the control of the control section 90 instead of the worker.

DESCRIPTION OF SYMBOLS 1... Machine tool, 10... Spindle unit, 11... Spindle, 12... Headstock, 12a... Nut, 20... Z-axis movement mechanism, 21... Rail, 21a... Ball screw, 21b... Z-axis motor, 30... Tool mechanism , 31, 32... Tool unit, 31a, 32a... Tool, 31b, 32b... Tool rest, 33... X-axis moving mechanism, 34... Y-axis moving mechanism, 41... Fixed base, 41a... Cavity part, 50... Rotating tool device , 51...Rotary tool, 52...Tool holder, 53...Spindle shaft, 53a...Tip, 53b...Base end, 54...Rotary tool motor, 54a...Motor output shaft, 54b...Coupling for connection, 55...Housing , 55a...bearing, 80...guide bush device, 90...control unit, A...center axis of main spindle (work axis), S...bed

Claims (3)

a tool holder that holds a rotary tool for machining a workpiece held by a spindle;
a spindle shaft formed such that the tool holding portion can be attached to the tip;
a motor having an output shaft directly connected to a base end of the spindle shaft and rotating the spindle shaft together with the tool holding portion;
one casing that supports the motor, accommodates a plurality of spindle shafts arranged parallel to each other, and rotatably accommodates the spindle shafts;
A plurality of the motors are provided on each of the plurality of spindle shafts with specifications according to the rotary tool ,
The cutting edge of the rotary tool is brought into contact with the workpiece and processed by relative movement between the axial direction of the workpiece held by the main shaft and the plurality of axial directions of the rotary tool,
Rotary tool equipment. The motors other than those for the rotary tool to be processed are stopped;
The rotary tool device according to claim 1. The rotary tool device according to claim 1 or 2 ,
the main shaft that rotatably holds the work;
Machine Tools.

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