WO2017203824A1

WO2017203824A1 - Machine tool

Info

Publication number: WO2017203824A1
Application number: PCT/JP2017/012798
Authority: WO
Inventors: 克史湯口; 雄二増田; 康直笹井; 近藤　智行
Original assignee: スター精密株式会社
Priority date: 2016-05-23
Filing date: 2017-03-29
Publication date: 2017-11-30
Also published as: TW201741052A; JP2017209737A

Abstract

Provided is a machine tool capable of reducing the amount of heat generated while limiting increases in the size of the cutting tool holder in the axial direction of the rotating tool. The machine tool (1) is provided with a cutting tool holder (10) with a tool placement surface (50) on which multiple rotating tools (T2), which are rotated by a rotation-driving force (F1) that is transmitted to driven gears (G1), are disposed so as to project in the axial direction (D1) of the rotating tools. The cutting tool holder (10) comprises: a transmitting gear (60), which is capable of moving along an imaginary plane (PL1) that passes through the multiple driven gears (G1) and which meshes directly or indirectly with each of the multiple driven gears (G1) at different positions (P1-P6); a rotation-driving section (70) for meshing with the transmitting gear (60) to rotate the transmitting gear (60); and an object selection section (80) for moving the transmitting gear (60) along the imaginary plane (PL1) and positioning the transmitting gear (60) so as to mesh directly or indirectly with the driven gear (G10) to be driven that has been selected from the multiple driven gears (G1).

Description

Machine Tools

The present invention relates to a machine tool including a tool post having a tool placement surface on which a plurality of rotary tools are arranged in a state of protruding in the axial direction of the rotary tool.

As machine tools, a front spindle and a rear spindle for gripping a workpiece, a front machining tool post, and a lathe equipped with a rear machining tool post are known. The turret may be used in a state in which a plurality of rotary tools that are rotated by the rotational driving force transmitted to the driven gear are arranged on the same tool arrangement surface. In this case, the axial directions of the plurality of rotary tools are parallel to each other, and each rotary tool protrudes in the axial direction from the tool placement surface. The tool placement surface of the back machining tool post is directed to the back spindle side, for example. In this case, the back machining tool post is arranged on the machine body with the surface opposite to the tool arrangement surface facing the front machining tool post.
The drive unit for rotating the rotary tool rotates all the rotary tools mounted on the back working tool post together.

The multi-axis machining unit disclosed in Patent Document 1 is a machining unit for performing drilling and tapping, but in relation to a plurality of drive shafts provided in the head, each of them is moved forward and backward in the axial direction. An operating shaft for driving and rotating the spindle is provided. Each drive shaft is wrapped in a drive sleeve. Of the plurality of drive sleeves, the drive sleeve in the backward limit faces the non-rotating conduction means and does not rotate. Therefore, the tool corresponding to this drive sleeve does not rotate. On the other hand, the drive sleeve that is moving forward among the plurality of drive sleeves is rotated by the rotation conducting means. Therefore, the tool corresponding to this drive sleeve rotates.

Japanese Patent Laid-Open No. 9-11014

When all the rotary tools mounted on the back working tool post are rotated together, heat is generated accordingly. Therefore, if the rotary tool used for workpiece machining can be selectively rotated, the amount of heat generation can be reduced, leading to improved stability of machining accuracy.
However, since the above-described back working tool post has the front working tool post on the front main spindle side, there is a limitation in the dimension in the rotary tool axis direction. For this reason, it is difficult to provide the rear working tool post with a mechanism that moves in the axial direction in order to selectively rotate the rotary tool as in the drive sleeve disclosed in Patent Document 1.

The above-mentioned problem may exist not only for the back working tool post but also for the front working tool post.

The present invention has an object to provide a machine tool capable of reducing the amount of heat generation while suppressing an increase in the size of the tool post in the axial direction of the rotary tool.

The present invention is a machine tool provided with a tool post having a tool placement surface on which a plurality of rotary tools rotated by a rotational driving force transmitted to a driven gear protrude in the axial direction of the rotary tool,
The tool post is
A transmission gear that is movable along an imaginary plane passing through the plurality of driven gears and meshes directly or indirectly with each of the plurality of driven gears at different positions;
A rotation drive unit that meshes with the transmission gear and rotates the transmission gear;
An object selection unit that moves the transmission gear along the virtual plane and places the transmission gear in a position that directly or indirectly meshes with a driven gear that is selected from the plurality of driven gears. It has an aspect.

According to the present invention, it is possible to provide a machine tool capable of reducing the amount of heat generation while suppressing the increase in the size of the tool post in the direction of the rotary tool axis.

It is a top view which shows the example of a lathe typically. It is a perspective view which shows typically the example of the principal part of the tool post for back processing. It is a side view which shows typically the example of the rotary tool provided with the driven gear. It is a perspective view which shows typically the example of the gear structure of the tool post for back processing. It is a figure which shows typically the structural example of the tool post for back processing. 6A and 6B are perspective views schematically showing examples of planetary gear units. It is a figure which shows typically the structural example of the tool post for back processing. It is a perspective view which shows typically the example which changed the position of the planetary gear. It is a perspective view which shows typically the gear structure of the tool post for back processing which concerns on a comparative example.

Hereinafter, embodiments of the present invention will be described. Of course, the following embodiments are merely examples of the present invention, and all the features shown in the embodiments are not necessarily essential to the means for solving the invention.

(1) Summary of technology included in the present invention:
First, the outline of the technology included in the present invention will be described with reference to the examples shown in FIGS. In FIG. 1 and the like, a spindle moving lathe 1 is shown as an example of a machine tool. FIGS. 1 to 8 are schematic views, and the enlargement ratios in the respective directions shown in these figures may be different, and the figures may not be consistent.

The tool rest 10 of the machine tool (1) of the present technology illustrated in FIGS. 1 to 8 includes a plurality of rotating tools T2 that are rotated by the rotational driving force F1 transmitted to the driven gear G1 and project in the rotating tool axial direction D1. It has a tool placement surface 50 to be placed, and further has a transmission gear (for example, planetary gear 60), a rotation drive unit 70, and an object selection unit 80. The transmission gear (60) is movable along an imaginary plane PL1 (see FIG. 5) that passes through the plurality of driven gears G1, and has different positions (for example, positions P1 to P6) with respect to each of the plurality of driven gears G1. Mesh directly or indirectly. The rotation drive unit 70 meshes with the transmission gear (60) and rotates the transmission gear (60). The object selection unit 80 moves the transmission gear (60) along the virtual plane PL1, and directly or indirectly moves the transmission gear (60) to the driven gear G10 to be driven selected from the plurality of driven gears G1. Set to the meshing position.

For example, as illustrated in FIG. 1, a front headstock 21 provided with a front main spindle 31, a guide bush 40, a rear headstock 22 provided with a rear main spindle 32, a comb tool post 11, a back processing tool post 12, Are provided on the lathe 1. In FIG. 1, the front headstock 21 is movable in the Z1 axis direction, the back mainstock 22 is movable in the Z2 axis direction and the X2 axis direction, and the comb tool post 11 is moved in the X1 axis direction and the Y1 axis direction. The back working tool post 12 is movable in the Y2 axis direction. As illustrated in FIG. 2, rotary tools T22, T23, T24, and T25 are arranged on the upper stage on the tool placement surface 50 on the side facing the back spindle 32 in the back machining tool post 12, and below the rotary tool T22. It is assumed that the rotary tool T21 is arranged at the bottom, and the rotary tool T26 is arranged below the rotary tool T25. The rotary tools T21 to T26 are collectively referred to as a rotary tool T2. The back machining tool post 12 moves in the Y2 axis direction, and the back spindle 32 that grips the workpiece W2 that has been machined in front moves in the X2 axis direction, so that the workpiece W2 faces one of the rotary tools T2. be able to.

FIG. 9 schematically shows the gear structure of the back working tool post according to the comparative example. Each rotary tool T2 is provided with a driven gear G1 that is rotatable about a rotation axis AX10 (see FIG. 2) of the rotary tool T2, and rotates by a rotational driving force transmitted to the driven gear G1. Of the six driven gears G1, idler gears G91 mesh with the driven gears G11, G12, G13, and idler gears G92 mesh with the driven gears G14, G15, G16. The idler gears G91 and G92 mesh with an idler gear G93, the idler gear G93 meshes with an idler gear G94, and the idler gear G94 meshes with a drive gear G95. When a rotary tool drive motor (not shown) rotates the drive gear G95, the rotational drive force is transmitted to both the idler gears G91 and G92 via the idler gears G94 and G93. From the idler gear G91, the rotational driving force is transmitted to all of the driven gears G11, G12, G13, and from the idler gear G92, the rotational driving force is transmitted to all of the driven gears G14, G15, G16. Therefore, when the drive gear G95 rotates, all of the rotary tools T21 to T26 rotate.

Here, when the rotary tools T21 to T26 rotate together, heat is generated by friction between the bearing part of the rotary tool and the sliding part of the cooling oil sealant. If the heat generation continues, there is a possibility that the tool post body will thermally expand, and this thermal expansion may cause an error in the position of the tool and cause variations in the finished product dimensions. On the other hand, in order to selectively transmit the rotational driving force to the rotary tool, a selection mechanism for that purpose is required. However, the back working tool post 12 shown in FIG. 1 cannot be enlarged in the rotary tool axial direction D1 for providing the selection mechanism for the following reason.

The workpiece W1 held by the guide bush 40 is processed by the tool T1 mounted on the comb tool post 11. Since the guide bush 40 is attached to the support base 24 so as not to move in the Z1 axis direction, the comb tool post 11 is also attached to the base 2 so as not to move in the Z1 axis direction. Since the back working tool post 12 is arranged on the comb tool post 11 with the surface 51 opposite to the tool placement surface 50 facing, the rotary tool axial direction D1 of the back working tool post 12 is set.
Is limited in length (depth D).
Further, since there is an exterior 3 in front of the comb tool post 11 (in the + X1 axis direction), the back working tool post 12 is placed in front of the comb tool post 11 in order to increase the depth D of the back processing tool post 12. Can not be placed in.

As illustrated in FIGS. 4 to 8, in the above aspect of the present technology, the transmission gear (60) meshes with each of the plurality of driven gears G1 directly or indirectly at different positions (P1 to P6). The rotational driving force F1 is not transmitted to the driven gear G1 that is not directly or indirectly meshed with the gear (60). Thereby, the rotating tool which is not selected does not rotate, the amount of heat generation is reduced, and as a result, the stability of machining accuracy is improved. The transmission gear (60) moves along a virtual plane PL1 passing through the plurality of driven gears G1. This eliminates the need to move the transmission gear (60) in the rotary tool axial direction D1 in order to selectively rotate the rotary tool T2. Therefore, this aspect can provide a machine tool that can reduce the amount of heat generation while suppressing an increase in the size of the tool post in the direction of the rotary tool axis.

Here, the indirect meshing of the transmission gear with the driven gear includes the direct meshing of the transmission gear with the idler gear meshing with the driven gear, the direct meshing of the transmission gear with the idler gear train, and the like. In this technology, some driven gears directly mesh with the transmission gear and the remaining driven gears mesh indirectly with the transmission gear, all the driven gears mesh directly with the transmission gear, and all the driven gears communicate with the transmission gear. Including indirect meshing.

By the way, the rotational drive unit 70 may have a sun gear 71 that meshes with the transmission gear (60) and transmits the rotational driving force F1 to the transmission gear (60). The transmission gear (60) may be supported so as to be able to rotate with respect to the planet carrier 62 that can rotate around the rotation shaft 72 of the sun gear 71. The object selection unit 80 may rotate the planet carrier 62 around the rotation shaft 72 of the sun gear 71 and position the transmission gear (60) directly or indirectly in mesh with the driven gear G10 to be driven. In this aspect, since the transmission gear (60) functions as a planetary gear, it is possible to provide a suitable machine tool that reduces the amount of heat generation while suppressing an increase in the size of the tool rest in the direction of the rotary tool axis.

(2) Specific examples of machine tool configurations:
FIG. 1 is a plan view schematically illustrating a spindle moving NC (Numerical Control) lathe 1 as an example of a machine tool. The lathe 1 includes a front spindle 21 provided with a front spindle 31, a guide bush 40, a rear spindle 22 provided with a rear spindle 32, a comb tool post 11, and a back machining tool post 12 on a base 2. , Turrets 13 and the like. The front headstock 21 and the rear headstock 22 are collectively referred to as the headstock 20, the front main spindle 31 and the rear main spindle 32 are collectively referred to as the main spindle 30, and the comb tool post 11, the rear working tool post 12, and the turret 13 are used as the tool. Collectively referred to as table 10. For the sake of convenience, FIG. 1 also shows an NC device (numerical control device) 7 that numerically controls the operations of the headstock 20, guide bush 40, tool post 10 and the like, but the NC device 7 is in the position shown in FIG. Is not limited.

In FIG. 1, the front spindle 31 is movable in the Z1 axis direction together with the front spindle stock 21, the back spindle 32 is movable in the Z2 axis direction and the X2 axis direction together with the rear spindle stock 22, and the comb tool post 11 is It can move in the X1 axis direction and the Y1 axis direction, the back working tool post 12 can move in the Y2 axis direction, and the turret 13 can move in the X3 axis direction, the Y3 axis direction, and the Z3 axis direction. The X1-axis direction, the X2-axis direction, and the X3-axis direction are the same direction, and are collectively referred to as the X-axis direction. The Y1-axis direction, the Y2-axis direction, and the Y3-axis direction are the same direction and are collectively referred to as the Y-axis direction. The Z1 axis direction, the Z2 axis direction, and the Z3 axis direction are the same direction and are collectively referred to as the Z axis direction.

The base 2 is also called a bed, a table, or the like, and constitutes a base part that directly or indirectly supports the above-described

parts

10, 20, 40, and the like. FIG. 1 shows that the base 2 supports the guide bush 40 via the support base 24.

A spindle 30 provided on the spindle stock 20 releasably holds a columnar (rod-like) workpiece W1 inserted in the longitudinal direction, and the workpiece W1 around the spindle centerlines AX1 and AX2 along the longitudinal direction of the workpiece W1. Rotate. The guide bush 40 supports a long workpiece W1 penetrating the front main shaft 31 in the Z1 axis direction so as to be slidable in the Z1 axis direction, and is driven to rotate about the main shaft center line AX1 in synchronization with the front main shaft 31. . Thereby, bending of an elongate workpiece | work is suppressed and a highly accurate process is performed. A portion of the work W1 that protrudes from the guide bush 40 in the + Z1 axial direction is front-faced by the comb tool post 11 and the turret 13. The back spindle 32 releasably grips the workpiece W2 that has been processed in the front and inserted in the Z2 axis direction, and rotates the workpiece W1 about the spindle center line AX2. Note that the concept of the workpiece W2 that has been processed in front is included in the concept of the workpiece W1. For example, the back spindle 32 that grips the workpiece W2 cut off by the cutting tool included in the tool T1 moves in the X2 axis direction to rotate the rotary tool T2 of the back working tool post 12.
It is possible to make the workpiece W2 face each other.

The tool post 10 is equipped with various tools T1 including a rotary tool T2 such as a rotary drill. The comb-shaped tool post 11 is arranged on the + X1 axial direction side from the guide bush 40, and can perform front machining on the workpiece W1 gripped by the guide bush 40 with various tools T1. The comb tool post 11 may perform back surface processing on the workpiece W <b> 2 gripped by the back main shaft 32. The turret 13 is mounted with a plurality of tools T1 radially about the indexing axis AX3, can turn about the indexing axis AX3, and can perform front machining. The turret 13 may also be subjected to back processing. The back working tool post 12 is arranged on the + Z1 axis direction side from the comb tool post 11 and can perform back working on the workpiece W2 held by the back main spindle 32.

The NC device 7 includes a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), a clock circuit, an interface (I / F), and the like. An NC program is executed upon receiving information input. The operator can store the NC program in the RAM of the NC device 7 using an operation panel or an external computer. The NC device 7 of this specific example can control the operation of the drive motors 74 and 81 (see FIG. 5) so as to selectively rotate the rotary tool T2 mounted on the back surface processing tool post 12.

FIG. 2 schematically illustrates a main part of the back working tool post 12. The rotary tool T2 mounted on the back working tool post 12 is disposed on the tool placement surface 50 on the side facing the back main spindle 32. As illustrated in FIG. 3, each rotary tool T2 is provided with a driven gear G1 that is rotatable about a rotation axis AX10 of the rotary tool T2, and a rotational driving force F1 transmitted to the driven gear G1 (see FIG. 7). Rotates about the rotation axis AX10. A plurality of rotary tools T2 are arranged on the tool arrangement surface 50 in a state of protruding in the rotary tool axial direction D1.

FIG. 4 is a perspective view schematically illustrating a gear structure arranged on the back surface 50b of the tool arrangement surface 50 with the illustration of the surface 51 opposite to the tool arrangement surface 50 in the back surface processing tool post 12 omitted. is there. FIG. 5 schematically illustrates the configuration of the back surface processing tool post 12 as viewed from the + X1 direction side.
The driven gears G11, G12, G13, G14, G15, and G16 shown in FIG. 4 are provided on the rotary tools T21, T22, T23, T24, T25, and T26, respectively. Of the six driven gears G1, the idler gear G22 meshes with the driven gear G12, and the idler gear G25 meshes with the driven gear G15. The idler gears G22 and G25 are collectively referred to as an idler gear G2. The idler gear is also an intermediate gear arranged between the driving side gear and the driven gear, and the side on which the rotational driving force from the driving side gear is driven without any rotational driving force from other than the driving side gear. Tell the gears. The direction of the rotating shaft of the idler gear G2 shown in FIG. 4 is the direction along the rotating tool axis direction D1. Here, as shown in FIG. 5, a virtual plane passing through the gears G11 to G16, G22, and G25 is defined as a plane PL1. The virtual plane PL1 is orthogonal to the rotary tool axis direction D1, but may be a plane that is not orthogonal as long as it is offset from the rotary tool axis direction D1. The fact that the virtual plane deviates from the direction orthogonal to the rotary tool axis direction due to an error in machining dimensions or the like is included in the fact that the virtual plane is orthogonal to the rotary tool axis direction.

The back working tool post 12 of this specific example includes a planetary gear unit U1, a unit driving gear 82, and a gear 75 for selectively transmitting the rotational driving force F1 to the driven gear G10 to be driven from the driven gears G11 to G16. , 76, 77 and drive

motors

74, 81.

FIG. 6A illustrates the sun gear side of the planetary gear unit U1. FIG. 6B illustrates the planet carrier side of the planetary gear unit U1. The planetary gear unit U1 shown in FIGS. 6A and 6B has a sun gear 71, a planet carrier 62, a planetary gear 60 (an example of a transmission gear), and a unit driven gear 63. The sun gear 71 passes through an imaginary plane PL1 shown in FIG. 5, meshes with the planetary gear 60, and can rotate around the rotation shaft 72 shown in FIG. The rotating shaft 72 shown in FIG. 5 is oriented along the rotating tool axis direction D1, and is orthogonal to the virtual plane PL1. The planet carrier 62 is closer to the tool placement surface 50 than the virtual plane PL1, and can rotate around the rotation shaft 72 of the sun gear 71. The planetary gear 60 passes through an imaginary plane PL1, is supported so as to be rotatable about the rotation axis 61 with respect to the planet carrier 62 in a state of meshing with the sun gear 71, and rotates along the imaginary plane PL1. It can move around the sun gear 71 in an arc. The rotating shaft 61 of the planetary gear is oriented along the rotating tool axis direction D1, and is orthogonal to the virtual plane PL1. The unit driven gear 63 is located between the sun gear 71 and the planet carrier 62, is fixed relative to the planet carrier 62, and can rotate around the rotation shaft 72 of the sun gear 71.

FIG. 7 schematically illustrates the configuration of the back working tool post 12 as viewed from the −Z1 direction side. The planetary gear 60 shown in FIG. 7 directly meshes with the driven gear G11 at the meshing position P1, directly meshes with the idler gear G22 at the meshing position P2, directly meshes with the driven gear G13 at the meshing position P3, and directly meshes with the driven gear G14 at the meshing position P4. The meshing position directly meshes with the idler gear G25 at the meshing position P5, and meshes directly with the driven gear G16 at the meshing position P6. Since the idler gear G22 meshes with the driven gear G12, the planetary gear 60 meshes indirectly with the driven gear G12 at the meshing position P2. Since the idler gear G25 meshes with the driven gear G15, the planetary gear 60 meshes indirectly with the driven gear G15 at the meshing position P5. Since the meshing positions P1 to P6 are different from each other, the planetary gear 60 is meshed directly or indirectly with each of the driven gears G11 to G16 at different meshing positions P1 to P6.

The back surface processing tool post 12 has a target selection unit 80 that moves the planetary gear 60 along the outer periphery of the sun gear 71. The object selection unit 80 includes a unit drive gear 82 that meshes with the unit driven gear 63, and a planet carrier drive motor 81 that rotates the unit drive gear 82. The planet carrier drive motor 81 is a servo motor having a self-locking function, and is connected via a unit drive gear 82 and a unit driven gear 63 so that the planet carrier 62 does not rotate at a rotation position according to an instruction from the NC device 7. Can be fixed. For example, when the NC device 7 reads a command to selectively use the rotary tool T21 from the NC program when the planetary gear 60 is not in the position P1 where the planetary gear 60 is engaged with the driven gear G11, the NC device 7 rotates the planetary carrier 62 according to the engagement position P1. An instruction to set the position is issued to the planetary carrier drive motor 81. Receiving this instruction, the planet carrier driving motor 81 rotates the planet carrier 62 through the

gears

82 and 63 so that the planetary gear 60 is brought into the meshing position P1, and the

gears

82 and 63 are rotated at the rotational positions corresponding to the meshing position P1. The planet carrier 62 is fixed via FIG. 4 shows that the driven gear G11 is selected as the driven gear G10 to be driven, and the planetary gear 60 at the meshing position P1 is meshed with the driven gear G11. The object selection unit 80 moves the planetary gear 60 to any of the meshing positions P1 to P6 around the rotation shaft 72 of the sun gear 71, and meshes the planetary gear 60 directly or indirectly with the driven gear G10 to be driven. To position.

The position of the planet carrier drive motor 81 is not limited to the position shown in FIG. 7 and can be changed as appropriate. For example, in FIG. 7, a planet carrier drive motor 81 and a unit drive gear 82 are arranged on the right side of the back working tool post 12, and a wheel train that transmits rotational force between the unit drive gear 82 and the unit driven gear 63 ( A plurality of idler gears) may be arranged.
Further, the fixing of the planet carrier 62 is not limited to the self-locking function of the planet carrier driving motor itself. For example, an excitation operation type electromagnetic clutch (non-excitation operation type electromagnetic brake) that disconnects the power transmission system by electromagnetic force generated by energization is provided on the rotation shaft of the unit drive gear 82 or the rotation shaft of the unit driven gear 63. May be.

Further, the back working tool post 12 has a rotational driving force transmission system for rotating the planetary gear 60 for transmission of the rotational driving force F1. The rotational driving force transmission system includes an idler gear 77 meshed with the sun gear 71, an idler gear 76 meshed with the idler gear 77, a drive gear 75 meshed with the idler gear 76, and a rotary tool drive motor 74 that rotates the drive gear 75. have. The rotational driving force transmission system and the sun gear 71 function as the rotational driving unit 70 in this specific example. The NC device 7 issues an instruction to rotate the drive gear 75 to the rotary tool drive motor 74 when a command to rotate the rotary tool to be driven selected from the rotary tools T21 to T26 is read from the NC program. Upon receiving this instruction, the rotary tool drive motor 74 rotates the drive gear 75, rotates the planetary gear 60 via the idler gears 76, 77 and the sun gear 71, and finally drives via the driven gear G10 to be driven. Rotate the target rotating tool. In this way, the rotational drive force F1 from the rotary tool drive motor 74 is transmitted to the driven gear G10 to be driven through at least the drive gear 75, the idler gears 76 and 77, the sun gear 71, and the planetary gear 60. . When the NC device 7 issues an instruction to stop the rotation of the drive gear 75 to the rotary tool drive motor 74, the rotary tool drive motor 74 that has received this instruction stops the rotation of the drive gear 75 and at least the idler gear 76. , 77, the sun gear 71, and the planetary gear 60, the rotation of the driven gear G10 to be driven is stopped.
In addition, the direction of the rotating shaft of the

gears

75, 76, 77, 82 shown in FIGS. 4 and 5 is also the direction along the rotating tool axis direction D1.
Further, when the planetary gear 60 rotates in a certain rotation direction, rotary tools T22 and T25 provided with driven gears G12 and G15 meshed with idler gears G22 and G25 and driven gears G11, G13, G14 and G16 were provided. The rotation direction is opposite to that of the rotary tools T21, T23, T24, and T26. Therefore, the rotation direction of the rotary tool drive motor 74 is controlled so that the rotation direction is reversed between when the planetary gear 60 is in the meshing positions P2 and P5 and when the planetary gear 60 is in the meshing positions P1, P3, P4 and P6. That's fine.

(3) Actions and effects of the above specific examples:
Next, the operation and effect of the above specific example will be described.
For example, when the planetary gear 60 is in the meshing position P1 shown in FIG. 7, the planetary gear 60 is directly meshed with the driven gear G11 (driven gear G10) as shown in FIG. In this case, the rotational driving force F1 from the motor 74 is transmitted to the driven gear G11 via the

gears

75, 76, 77, 71, 60, and the rotary tool T21 rotates. At this time, the rotational driving force F1 is not transmitted to the driven gears G12 to G16, and the rotary tools T22 to T26 do not rotate.

Here, it is assumed that the NC device 7 issues an instruction to the planetary carrier drive motor 81 to set the planetary carrier 62 to a rotational position corresponding to the meshing position P5 in accordance with a command to selectively use the rotary tool T25. Receiving this instruction, the planet carrier driving motor 81 rotates the planet carrier 62 via the unit driving gear 82 and the unit driven gear 63 so as to move the planet gear 60 from the meshing position P1 to the meshing position P5, and the meshing position P5. The planetary carrier 62 is fixed through the

gears

82 and 63 at a rotational position corresponding to the above. FIG. 8 shows that the driven gear G10 to be driven is switched to the driven gear G15, and the planetary gear 60 at the meshing position P5 is engaged with the driven gear G15. Upon receiving an instruction to rotate the drive gear 75 from the NC device 7, the rotary tool drive motor 74 rotates the drive gear 75, and idler gears 76 and 77, sun gear 71, planetary gear 60, idler gear G25, and driven gear G15. The rotary tool to be driven is rotated via the. That is, the rotational drive force F1 from the rotary tool drive motor 74 is transmitted to the driven gear G15 via the

gears

75, 76, 77, 71, 60, G25, and the rotary tool T25 rotates. At this time, the rotational driving force F1 is not transmitted to the driven gears G11 to G14 and G16, and the rotary tools T21 to T24 and T26 do not rotate.

As illustrated above, the planetary gear 60 meshes with each of the driven gears G11 to G16 directly or indirectly at different meshing positions P1 to P6, so that the driven gear that is not meshed directly or indirectly with the planetary gear 60 is used. The rotational driving force F1 cannot be transmitted. As a result, an unselected rotating tool does not rotate, vibration and noise are reduced, energy consumption is reduced, and the amount of heat generated by friction between the bearing portion of the rotating tool and the sliding portion of the cooling oil sealant is reduced. Less. As a result, the thermal expansion of the tool post body is suppressed, and the stability of processing accuracy is improved. Moreover, since the frequency of rotation of each rotary tool becomes low, the wear of the bearing of the rotary tool is reduced, leading to an improvement in the life of the rotary tool.

Further, since the planetary gear 60 moves along the virtual plane PL1 passing through the driven gears G11 to G16, it is not necessary to move the transmission gear in the rotary tool axial direction D1 in order to selectively rotate the rotary tool T2. If there is a comb-shaped tool post 11 in the −Z-axis direction from the back working tool post 12 and the exterior 3 is in front, the depth D of the back working tool post 12 is limited. There is no need to increase D. For this reason, the rotary tool switching mechanism can be housed in the back working tool post with the external dimensions of the back working tool post shown in FIG.

From the above, this example can provide a machine tool capable of reducing the amount of heat generation while suppressing the increase in the size of the tool post in the direction of the rotary tool axis.

(4) Modification:
Various modifications can be considered for the present technology.
For example, the tool post to which the present technology can be applied is not limited to the back working tool post, and may be a front working tool post such as the comb tool post 11 as long as it has a rotary tool. Moreover, this technique is applicable also to machine tools other than a lathe.
In addition to the rotating tool, a tool that does not rotate may be arranged on the tool arrangement surface.

The layout of the rotary tool with respect to the tool placement surface can be variously designed such that the number of rotary tools is three or more in the Y-axis direction and the number of rotary tools is five or more in the X-axis direction. For example, in the tool arrangement surface 50 shown in FIG. 2, another rotary tool may be arranged under the rotary tool T21, and another rotary tool may be arranged under the rotary tool T26.
Further, two or more components having rotating tools T21 to T26, driven gears G11 to G16, idler gears G22 and G25, and planetary gear unit U1 are arranged, and a set to be used is selected by a link mechanism or the like. The planetary gear 60 may be selectively meshed with the driven gear G10. It is also included in the present technology to selectively rotate the rotary tool in this way.

The angle formed between the virtual plane on which the planetary gear moves and the rotation tool axis direction is preferably 90 °, but may be, for example, less than 90 ° and 60 ° or more, and is not limited to 90 °.
Further, the transmission gear that meshes directly or indirectly with each of the plurality of driven gears at different positions may be moved along an imaginary plane passing through the plurality of driven gears, and is not limited to a planetary gear.

(5) Conclusion:
As described above, according to the present invention, according to various aspects, it is possible to provide a technology such as a machine tool that can reduce the amount of heat generation while suppressing the increase in the size of the tool post in the direction of the rotary tool axis. Needless to say, the above-described basic actions and effects can be obtained even with a technique that does not have the constituent elements according to the dependent claims but includes only the constituent elements according to the independent claims.
In addition, the configurations disclosed in the above-described examples are mutually replaced or the combination is changed, the known technology and the configurations disclosed in the above-described examples are mutually replaced or the combinations are changed. The configuration described above can also be implemented. The present invention includes these configurations and the like.

DESCRIPTION OF SYMBOLS 1 ... Lathe (example of machine tool) 2 ... Base 3 ... Exterior, 7 ... Numerical control device,
10 ... Turret, 11 ... Comb turret, 12 ... Turret for back machining,
13 ... Turret,
20 ... headstock, 21 ... front headstock, 22 ... back headstock, 24 ... support base,
30 ... main shaft, 31 ... front main shaft, 32 ... back main shaft, 40 ... guide bush,
50 ... Tool placement surface, 50b ... Back side,
60 ... Planetary gear (example of transmission gear), 61 ... Rotating shaft, 62 ... Planetary carrier,
63 ... unit driven gear,
70 ... Rotation drive part, 71 ... Sun gear, 72 ... Rotation shaft,
74: Rotary tool drive motor, 75: Drive gear, 76, 77 ... Idler gear,
80 ... object selection unit, 81 ... planet carrier drive motor,
82: Unit drive gear,
AX10: Rotating shaft, D1: Rotating tool axial direction, F1: Rotational driving force,
G1, G11 to G16 ... driven gear, G2, G22, G25 ... idler gear,
G10: driven gear to be driven,
P1 to P6 ... position, PL1 ... plane,
T1, ... tool, T2, T21 to T26 ... rotating tool,
U1 ... Planetary gear unit,
W1 ... Work, W2 ... Work processed in front.

Claims

A machine tool including a tool post having a tool placement surface in which a plurality of rotary tools that rotate by a rotational driving force transmitted to a driven gear project in the axial direction of the rotary tool,
The tool post is
A transmission gear that is movable along an imaginary plane passing through the plurality of driven gears and meshes directly or indirectly with each of the plurality of driven gears at different positions;
A rotation drive unit that meshes with the transmission gear and rotates the transmission gear;
An object selection unit that moves the transmission gear along the virtual plane and places the transmission gear in a position that directly or indirectly meshes with a driven gear that is selected from the plurality of driven gears. Machine Tools.
The rotational drive unit includes a sun gear that meshes with the transmission gear and transmits the rotational driving force to the transmission gear;
The transmission gear is supported so as to be able to rotate with respect to a planet carrier that can rotate around the rotation axis of the sun gear,
2. The machine tool according to claim 1, wherein the object selection unit rotates the planet carrier around a rotation axis of the sun gear so that the transmission gear meshes directly or indirectly with the driven gear to be driven. machine.