Machine tool

Abstract

A machine tool according to an aspect has a partition with which a space above a base in a housing is separated into a machining chamber in which machining with a tool is performed and a storage chamber in which a headstock is accommodated. The machine tool includes: a workpiece spindle rotatably supported by the headstock hand having a leading end exposed to the machining chamber; a coolant discharge part located in the machining chamber and configured to discharge a coolant during machining of a workpiece supported by the workpiece spindle; a mist collector located in a space above the headstock and having an outlet open on a side face of the housing; a mist intake formed on the partition and being open toward the machining chamber; and a pipe arranged in the storage chamber and connecting an inlet of the mist collector with the mist intake.

Description

MACHINE TOOL

[0001] The present invention relates to a machine tool, and particularly to an arrangement of a mist collector for collecting misty coolant.

[0002] During machining of a workpiece in a machine tool, coolant is supplied to cool a tool and the workpiece and remove chips. Because the coolant is in a misty state in a machining chamber, the misty coolant being discharged out from the machine tool can cause contamination in a factory. Mist collectors for collecting misty coolant have therefore been installed (refer to PTL 1 and PTL 2).

[0003] JP 6915131 B1JP 7144631 B1

[0004] Such a mist collector is typically installed separately from a machine tool or attached onto an outer face of a housing (splash guard) of a machine tool. In the former case, a space for installation of a mist collector needs to be secured outside of the machine tool. A space for pipes connecting the machining chamber with the mist collector is also needed. In the latter case as well, a space for the mist collector needs to be secured outside of the machine tool. Thus, interference between these structures and other structures has to be prevented.

[0005] An embodiment of the present invention is a machine tool having a partition with which a space above a base in a housing is separated into a machining chamber in which machining with a tool is performed and a storage chamber in which a headstock is accommodated. The machine tool includes: a workpiece spindle rotatably supported by the headstock hand having a leading end exposed to the machining chamber; a coolant discharge part located in the machining chamber and configured to discharge a coolant during machining of a workpiece supported by the workpiece spindle; a mist collector located in a space above the headstock and having an outlet open on a side face of the housing; a mist intake formed on the partition and being open toward the machining chamber; and a pipe arranged in the storage chamber and connecting an inlet of the mist collector with the mist intake.

[0006] The present invention achieves a space-saving machine tool while maintaining the functions of a mist collector.

[0007] FIG. 1 is a perspective view of an external appearance of a machine tool according to an embodiment.FIG. 2 is a hardware configuration diagram of a machine tool.FIG. 3 is a perspective view of an internal structure of the machine tool.FIG. 4 is a front view of an internal structure of a storage chamber.FIG. 5 is a cross-sectional view as viewed in the direction of arrows A-A in FIG. 4, and illustrates a configuration of a mist collector.FIG. 6 is a view in the direction of an arrow B in FIG. 4.FIG. 7 is a cross-sectional view as viewed in the direction of arrows C-C in FIG. 6.FIGS. 8A and 8B illustrate an arrangement of a mist collector.FIGS. 9A to 9D illustrate a structure for maintenance of a mist collector.FIGS. 10A to 10C illustrate a structure for maintenance of the mist collector.FIGS. 11A to 11C illustrate a structure for filter replacement of the mist collector.FIGS. 12A and 12B illustrate a structure for filter replacement of the mist collector.FIG. 13 is a front view of an internal structure of a storage chamber according to a first modification.FIG. 14 is a front view of an internal structure of a storage chamber according to a second modification.FIG. 15 is a front view of an internal structure of a storage chamber according to a third modification.FIG. 16 is a front view of an internal structure of a storage chamber according to a fourth modification.FIG. 17 is a front view of an internal structure of a storage chamber according to a fifth modification.FIG. 18 is a diagram illustrating arrangement of a mist collector in a case where a storage chamber is on a right side as viewed from the front of a machine tool.

[0008] An embodiment of the present invention will now be described below with reference to the drawings. FIG. 1 is a perspective view of an external appearance of a machine tool according to an embodiment. Hereinafter, for convenience of explanation, the up-down direction, the front-back direction, and the left-right direction when a machine tool 1 is viewed from the front will be referred to as an X direction, a Y direction, and a Z direction, respectively.

[0009] The machine tool 1 is a turning center for machining a workpiece into a desired shape by appropriately changing tools. The machine tool 1 includes a machining chamber 4 inside a housing 2. Machining equipment for machining workpieces is installed in the machining chamber 4. An operation panel 6 for operating the machining equipment is installed on a side face of the housing 2.

[0010] A coolant tank 8 for storing coolant to be supplied to the machining chamber 4 is located adjacent to the housing 2 of the machine tool 1 (see FIG. 3). The machine tool 1 is provided with a mist collector 10 for collecting misty coolant (also referred to as “oil mist”) in the machining chamber 4. According to the present embodiment, the arrangement of the mist collector 10 is devised, which achieves a space-saving machine tool 1, details of which will be described hereinafter.

[0011] FIG. 2 is a hardware configuration diagram of the machine tool 1. The machine tool 1 includes an information processing device 100, a machining controller 102, and machining equipment 104. The machining controller 102 functions as a numerical controller, and outputs control signals to the machining equipment 104 in accordance with a machining program (NC program). The machining equipment 104 drives workpiece spindles and moves a tool in accordance with instructions from the machining controller 102 to machine a workpiece.

[0012] The machining equipment 104 includes a workpiece spindle driver 110, a turret driver 112, a coolant supply system 114, and a mist collector driver 116. In the present embodiment, as will be described later, the workpiece spindles capable of holding a workpiece include a first workpiece spindle and a second workpiece spindle. The workpiece spindle driver 110 includes a first spindle driver 120 for driving the first workpiece spindle and a second spindle driver 122 for driving the second workpiece spindle. The turret driver 112 drives a turret type tool rest, which will be described later.

[0013] The coolant supply system 114 supplies a coolant into the machining chamber 4. The coolant is used as a cutting fluid for removing heat from and lubricating a tool and a workpiece during machining, and also as a cleaning fluid for removing chips scattered in the machining chamber 4. The coolant supply system 114 includes, in addition to the coolant tank 8 mentioned above, coolant discharge parts 124, a pump 126, and a control valve 128, which are arranged on a coolant circulation path, which is not illustrated.

[0014] A plurality of coolant discharge parts 124 are provided in the machining chamber 4. Each of the coolant discharge parts 124 includes a nozzle for discharging the coolant and an actuator for driving the nozzle, and discharges the coolant toward a set target position. The pump 126 pumps up the coolant stored in the coolant tank 8 and supplies the pumped-up coolant to the coolant discharge parts 124. The control valve 128 includes a plurality of on-off valves to switch between coolant flow paths in the coolant circulation path.

[0015] The mist collector driver 116 drives the mist collector 10 when the coolant is discharged in the machining chamber 4. The mist collector driver 116 includes a motor 60 for driving a fan of the mist collector 10, which will be described in detail later.

[0016] The information processing device 100 includes the operation panel 6, and outputs control commands to the machining controller 102 in accordance with operational inputs performed by an operator. The information processing device 100 also controls screens displayed on a monitor of the operation panel 6 in accordance with operational inputs performed by the operator.

[0017] The components of the information processing device 100 are implemented by hardware including computing units such as central processing units (CPUs) and various co-processors, storage devices such as memories and storages, and wired or wireless communication lines that connect these units and devices, and software that is stored in the storage devices and supplies processing instructions to the computing units. Computer programs may be constituted by device drivers, operating systems, various application programs on upper layers thereof, and a library that provides common functions to these programs.

[0018] FIG. 3 is a perspective view of an internal structure of the machine tool 1. For convenience of explanation, a state without covers (splash guards) on the front face and the left and right side faces of the housing 2 is illustrated. The machine tool 1 includes a partition 12 with which a space above a bed 3 (base) in the housing 2 is separated into the machining chamber 4 and a storage chamber 5.

[0019] The machining equipment 104 includes a first headstock 14, a second headstock 16, a tool rest 18, and the like on the bed 3. The first headstock 14 is accommodated in the storage chamber 5, and the second headstock 16 and the tool rest 18 are accommodated in the machining chamber 4. The storage chamber 5, in which no movable member is present, has a size necessary and sufficient to accommodate the first headstock 14 and sufficiently smaller than the machining chamber 4. The first headstock 14 rotatably supports a first workpiece spindle 20. A leading end of the first workpiece spindle 20 extends through the partition 12 and is exposed to the machining chamber 4. A chuck capable of holding a workpiece is attached to the leading end of the first workpiece spindle 20. The first workpiece spindle 20 is driven to rotate by the first spindle driver 120 mentioned above.

[0020] The second headstock 16 rotatably supports a second workpiece spindle 22. The second headstock 16 is covered with a dedicated cover 17 for preventing entry of chips and coolant. The second workpiece spindle 22 is exposed through the cover 17. A chuck capable of holding a workpiece is attached to a leading end of the second workpiece spindle 22. The second workpiece spindle 22 is driven to rotate by the second spindle driver 122 mentioned above. The second workpiece spindle 22 may be replaced with a tailstock, which is not illustrated, as necessary.

[0021] The first workpiece spindle 20 and the second workpiece spindle 22 are arranged to coaxially face each other along the Z direction. Each of the first headstock 14 and the second headstock 16 includes a spindle motor for rotating the workpiece spindle. The second headstock 16 is movable in the Z direction by being driven by a movement mechanism, which is not illustrated. Specifically, the second headstock 16 is movable in a direction in which the second workpiece spindle 22 is moved toward or away from the first workpiece spindle 20, by which the distance between the first workpiece spindle 20 and the second workpiece spindle 22 can be adjusted. The movement mechanism is a feed screw mechanism using a ball screw, for example.

[0022] The tool rest 18 is located behind the second headstock 16 in the depth direction in the machining chamber 4, and functions as a “tool holder”. The tool rest 18 includes a turret base 24 and a turret 26. The turret base 24 has a rotary shaft extending in the Z direction, and rotatably supports the turret 26. The turret base 24 includes a spindle motor for driving the turret 26 to rotate. The turret 26 is provided with a plurality of clamping / unclamping mechanisms (not illustrated) along its periphery. The clamping / unclamping mechanisms allows tools of different types (not illustrated) to be attached and detached.

[0023] The turret base 24 is movable in the X, Y, and Z directions by being driven by a movement mechanism, which is not illustrated, to adjust the relative positions of a workpiece held by each workpiece spindle and a tool held by the turret 26. The movement mechanism is a feed screw mechanism using a ball screw, for example.

[0024] This structure enables the turret 26 to move in the X, Y, and Z directions. Furthermore, the turret 26 is rotatable about an axis extending in the Z direction to switch between tools used for machining. Specifically, the turret 26 can move in three orthogonal axial directions relative to a workpiece supported by one or both of the first workpiece spindle 20 and the second workpiece spindle 22, so that the workpiece can be cut or turned by a tool.

[0025] The aforementioned coolant discharge parts 124 are located at predetermined positions in the machining chamber 4 (not illustrated). The coolant discharge parts 124 discharge the coolant toward a tool during machining of a workpiece, and also discharge the coolant to flush out chips scattered in the machining chamber 4. Note that some or all of tools to be supported by the turret 26 may have functions of a so-called through-spindle coolant device. Specifically, each tool may have an internal passage through which the coolant flows and which communicates with the coolant circulation path. The tool has, at its leading end, a discharge outlet that is an end of the internal passage and through which the coolant is discharged. Discharge of the coolant from a leading end of a tool during machining as described above can improve the machining accuracy, shorten the machining time, increase the tool life, improve the chip removal performance, and the like.

[0026] Because the coolant discharged from the coolant discharge parts 124 is in a misty state in the machining chamber 4, the misty coolant being discharged out from the machine tool can cause contamination in a factory. The machine tool 1 is therefore provided with the mist collector 10 for collecting the oil mist. The mist collector 10 is located in a space above the first headstock 14 in the storage chamber 5. The partition 12 has a mist intake 28 that is open toward the machining chamber 4. A pipe 30 connecting an inlet 10a of the mist collector 10 with the mist intake 28 is arranged in the storage chamber 5.

[0027] A cover 32 for covering the mist intake 28 from above is provided on a side face of the partition 12. The cover 32 is open downward, and restricts direct entry of the coolant discharged from the coolant discharge parts 124 into the mist intake 28. When the mist collector 10 is driven, the oil mist in the machining chamber 4 is drawn into the mist intake 28 and delivered into the inlet 10a via the pipe 30. The oil mist is collected in the mist collector 10, and cleaned air is discharged through an outlet 10b.

[0028] FIG. 4 is a front view of an internal structure of the storage chamber 5. In the storage chamber 5, a support pillar 40 stands upright, in addition to the first headstock 14, on the bed 3. A table 42 is located on an upper end of the support pillar 40, and the mist collector 10 is placed on the table 42. The first headstock 14 is located on the near side in the depth direction in the storage chamber 5, and the support pillar 40 is located on the far side (at the back) in the depth direction. Because the table 42 extends from the upper end of the support pillar 40 toward the near side, the mist collector 10 is cantilevered and supported by the support pillar 40, and located on the near side relative to the support pillar 40 in the depth direction.

[0029] The mist collector 10 is located on the far side (at the back) relative to the first headstock 14. The outlet 10b of the mist collector 10 communicates with the outside of the machine tool via an opening 34 of the housing 2. Specifically, the opening 34 is formed at a position of the housing 2 corresponding to the position of the outlet 10b. The pipe 30 extends from the inlet 10a of the mist collector 10, is curved slightly toward the near side, and connected with the mist intake 28. The pipe 30 is located above the first headstock 14. In this manner, the arrangement of the mist collector 10 and the pipe 30 makes effective use of the space above the first headstock 14 in the storage chamber 5.

[0030] FIG. 5 is a cross-sectional view as viewed in the direction of arrows A-A in FIG. 4, and illustrates a configuration of the mist collector 10. The mist collector 10 has a case 50 in which a fan 52, a first filter 54, and a second filter 56 are accommodated. A flow passage 58 of air introduced through the inlet 10a is formed in the case 50. The flow passage 58 connects the inlet 10a with the outlet 10b. The first filter 54, the fan 52, and the second filter 56 are arranged in this order from the upstream side of the flow passage 58. The second filter 56 is located near the outlet 10b. The motor 60 for driving the fan 52 to rotate is located in the case 50. The fan 52 and the first filter 54 are coaxially mounted on a rotary shaft 62 of the motor 60.

[0031] The first filter 54 and the second filter 56 each have a mesh having a predetermined roughness, and successively collect the oil mist contained in the air introduced into the mist collector 10. The second filter 56 has a mesh that is finer than the mesh of the first filter 54, so as to collect the oil mist having small particle sizes that has not been caught by the first filter 54. A hood 64 (outlet cover) that surrounds the outlet 10b is removably attached to the case 50. Note that such a configuration of the mist collector 10 is known as also described in PTL 2 (JP 7144631 B1), for example, detailed description thereof will be omitted.

[0032] When the motor 60 is driven to activate the mist collector 10, the fan 52 and the first filter 54 axially rotate. This causes air containing oil mist in the machining chamber 4 to be sucked through the mist intake 28 (see FIG. 4) and delivered through the pipe 30 to the inlet 10a of the mist collector 10. In this process, the air introduced into the case 50 via the inlet 10a passes through the first filter 54, by which the oil mist is separated, and is delivered to the downstream side via the fan 52 (see two-dot chain arrows). The oil mist separated by the first filter 54 is returned to the machining chamber 4 via drain, which is not illustrated, and then collected in the coolant tank 8.

[0033] The air having passed through the first filter 54 passes through the second filter 56 by which the remaining oil mist is removed. The cleaned air resulting from the removal of the oil mist is let out of the machine tool via the outlet 10b.

[0034] FIG. 6 is a view in the direction of an arrow B in FIG. 4, and shows the position of the mist intake 28 in the machining chamber 4. The mist intake 28 is located on the near side in the depth direction in the machining chamber 4. Specifically, the mist intake 28 is provided at an upper position on the near side in the depth direction (the Y direction) of the partition 12. The mist intake 28 is located above (right above) the first workpiece spindle 20 exposed to the machining chamber 4.

[0035] The cover 32 has a necessary and sufficient size for covering the mist intake 28, and is located at a position avoiding an interference area (an area surrounded by a two-dot chain line) of the tool rest 18. The partition 12 has a recessed space 70 so as not to interfere with the tool rest 18 when the tool rest 18 moves in the X direction (see FIG. 3).

[0036] Note that, as illustrated in FIG. 4, the inlet 10a of the mist collector 10 is at a position that is relatively higher than the mist intake 28. Thus, the pipe 30 curves slightly downward from the inlet 10a toward the mist intake 28. As a result, the coolant that is liquefied in the pipe 30 easily returns to the machining chamber 4. In other words, droplets of the coolant easily flow from the mist intake 28 into the machining chamber 4.

[0037] FIG. 7 is a cross-sectional view as viewed in the direction of arrows C-C in FIG. 6. A leading end of the pipe 30 extends through an opening 72 of the partition 12. The leading end of the pipe 30 is slightly widened and protrudes into the machining chamber 4, and the open end thereof forms the mist intake 28. The cover 32 has a cover body 80 that covers the mist intake 28 from above and from a side, and a shield 82 on an inner side of the cover body 80. The shield 82 extends obliquely downward from a face of the cover body 80 facing the mist intake 28 to below the mist intake 28. This prevents the coolant scattered under the machining chamber 4 from splashing and directly entering into the mist intake 28.

[0038] An upper face of the cover body 80 is an inclined face that is inclined downward, so that droplets of coolant adhered to the upper face can be dropped down in the machining chamber 4. The cover body 80 is open downward, and also has a slit 84 having an appropriate size on a base end side of its side face. The slit 84 is located closer to the base end side of the pipe 30 than the mist intake 28. This prevents direct entry of the coolant into the mist intake 28 and provides a sufficient area for an inlet into which oil mist is delivered.

[0039] FIGS. 8A and 8B illustrate an arrangement of the mist collector 10. FIG. 8A illustrates a state in which the hood 64 is attached, and FIG. 8B illustrates a state in which the hood 64 is removed. For convenience of explanation, a state in which a front cover of the housing 2 is removed is illustrated in FIGS. 8A and 8B.

[0040] As illustrated in FIG. 8A, a main unit (that is, functional components such as the fan 52 and the filters 54 and 56) of the mist collector 10 is accommodated in the storage chamber 5, and only the hood 64 protrudes to the outside of the housing 2. The hood 64 restricts the direction in which air is discharged from the mist collector 10 in the factory, which prevents the air from being directed to workers, for example. Because only the hood 64 protrudes as described above, the size of protrusion from the housing 2 is reduced.

[0041] The hood 64 can be removed depending on the position and the state of installation in the factory. As illustrated in FIG. 8B, removal of the hood 64 reduces structures protruding from the faces of the housing 2 and achieves space savings.

[0042] FIGS. 9A to 9D and 10A to 10C illustrate a structure for maintenance of the mist collector 10. FIGS. 9A to 9D illustrate a support structure of the mist collector 10. FIGS. 9A and 9B are perspective views as viewed from above, and FIGS. 9C and 9D are perspective views as viewed from below. FIGS. 10A to 10C illustrate a method of taking out the mist collector 10 for maintenance.

[0043] As illustrated in FIGS. 9A and 9B, the table 42 is constituted by a bracket 42a and an oil pan 42b, which are assembled on each other. The bracket 42a is cantilevered and supported by the support pillar 40. The bracket 42a functions as a “fixed table” fixed to the upper end of the support pillar 40, and the oil pan 42b functions as a “movable table” that is slidable in the Z direction relative to the bracket 42a.

[0044] As also illustrated in FIGS. 9C and 9D, the bracket 42a has three guide holes 43 extending in the Z direction. A plurality of screw holes 44 are formed on a lower face of the oil pan 42b at positions corresponding to the guide holes 43 (FIG. 9D). The bracket 42a and the oil pan 42b are fastened to each other with a plurality of screws 45 attached from the lower face side of the bracket 42a (FIG. 9C). In the present embodiment, one screw 45 is located on a distal end side and two screws 45 are located on a base end side in the sliding direction of each guide hole 43. The guide holes 43 and the screws 45 constitute a “sliding mechanism”.

[0045] Specifically, the oil pan 42b is slidable relative to the bracket 42a when the screw 45 on the distal end side in the sliding direction is removed and the screws 45 on the based end side in the sliding direction are loosened (FIG. 9D). The oil pan 42b is movable in the Z direction with the mist collector 10 placed thereon. When the oil pan 42b reaches an end point in the sliding direction, the distal end sides of the guide holes 43 serve as stoppers that catch the screws 45 on the base end sides in the sliding direction, which stops the oil pan 42b. Thus, the oil pan 42b and the mist collector 10 do not fall off.

[0046] As illustrated in FIGS. 10A to 10C, for detaching the mist collector 10, a worker first removes a cover 11 located on a lower part of a side cover 2b (splash guard), detaches the pipe 30 from the mist collector 10, further removes some of the aforementioned screws 45 and loosens others of the screws 45.

[0047] Subsequently, the worker draws the oil pan 42b, on which the mist collector 10 is placed, out of the housing 2 through the opening 34 of the side cover 2b (splash guard) by sliding the oil pan 42b, and detaches the mist collector 10, which allows maintenance of the mist collector 10. In this process, the entire front cover 2a (splash guard) of the housing 2 need not be removed, which facilitates the maintenance work. In a modification, an upper part (including the opening 34) of the front cover 2a may be removed so that the oil pan 42b can be drawn out.

[0048] FIGS. 11A to 11C, 12A and 12B illustrate a structure for filter replacement of the mist collector 10. FIGS. 11A to 11C illustrate a structure for attachment of the case 50 and the hood 64. FIGS. 12A and 12B illustrate a structure for opening and closing the outlet 10b by the hood 64.

[0049] As illustrated in FIG. 11A, the hood 64 is attached to the case 50 to surround the outlet 10b. As illustrated in FIG. 11B, the hood 64 is attached near the outlet 10b with a hinge 64a, and can open and close the outlet 10b like a door. The hood 64 includes a plurality of straightening vanes 64b arranged in the vertical direction. Air discharged from the mist collector 10 is straightened obliquely upward and discharged to the outside by the straightening vanes 64b.

[0050] As illustrated in FIG. 11C, when the hood 64 is opened, the outlet 10b is open. In this state, the second filter 56 can be taken out. Specifically, the structure for opening and closing the hood 64 as described above facilitates replacement of the second filter 56.

[0051] As illustrated in FIGS. 12A and 12B, because the mist collector 10 is exposed through the opening 34 of the side cover 2b, the hood 64 can be easily opened and closed from outside the housing 2.

[0052] While a structure in which the hood 64 is attached to the case 50 in an openable and closable manner has been presented in the preset embodiment, a structure in which the hood 64 is removably attached to the case 50 may be adopted.

[0053] A machine tool has been described above on the basis of the embodiment. In the present embodiment, the first headstock 14 and the second headstock 16 are provided as headstocks for supporting a workpiece spindle. The space above the bed 3 in the housing 2 is partitioned into the machining chamber 4 and the storage chamber 5 with the partition 12, the first headstock 14 is located in the machining chamber 4, and the second headstock 16 is located in the storage chamber 5. Because chips and coolant scattering in the machining chamber 4 do not reach the storage chamber 5, no cover is needed for the first headstock 14.

[0054] Because the first headstock 14 is fixed to the bed 3, the storage chamber 5 has a necessary and sufficient size for installation of the first headstock 14 but has a free space above the first headstock 14. In the present embodiment, this free space is effectively used to accommodate the mist collector 10 in the housing 2. Because the mist collector 10 and the pipe 30 are located in the space above the first headstock 14 and structures installed or protruding outside the machine tool are reduced, a space-saving machine tool is achieved while the functions of the mist collector 10 are maintained.

[0055] In particular, because the support pillar 40 stands upright on the far side (at the back) in the storage chamber 5 and supports the mist collector 10 in a cantilever manner toward the near side, the mist collector 10 can be placed above the first headstock 14 without interference with the first headstock 14. Because the mist collector 10 and the first headstock 14 are spaced from each other, vibration of the mist collector 10 while being driven is prevented from being transmitted to the first headstock 14 or suppressed. Thus, the driving of the mist collector 10 does not affect the machining accuracy of workpieces.

[0056] In addition, in the machining chamber 4, the space above the first workpiece spindle 20 is effectively used by arrangement of the mist intake 28. This also prevents interference of the cover 32 of the mist intake 28 with the tool rest 18.Modifications

[0057] FIG. 13 is a front view of an internal structure of a storage chamber according to a first modification. In this modification, the hood 64 is also located inside the housing 2. According to this modification, protrusions of the mist collector 10 from the side cover 2b (splash guard) of the housing 2 are eliminated, which prevents interference with a worker working outside the housing 2. This makes use of a relatively plenty of space above the storage chamber 5.

[0058] FIG. 14 is a front view of an internal structure of a storage chamber according to a second modification. In this modification, the mist collector 10 is installed at a position on the far side in the storage chamber 5 within the width in the left-right direction (the width in the axial direction) of the first headstock 14 (see one-dot chain lines in FIG. 14). The support pillar 40 is installed at a position to the right of that in the embodiment illustrated in FIG. 4. This makes use of a relatively plenty of space on the far side (at the back) of the first headstock 14 in the storage chamber 5. According to this modification, a space (hereinafter also referred to as an “extra space”) can be made to the left of the first headstock 14 and the mist collector 10 in the storage chamber 5, which allows installation of other devices of the machine tool.

[0059] FIG. 15 is a front view of an internal structure of a storage chamber according to a third modification. In this modification, air discharged from the mist collector 10 is directed upward through the opening 34 through an upper face cover 2c (splash guard) of the housing 2. The mist collector 10 is located at substantially the same position as that in the second modification, and a pipe 33 connecting the outlet 10b of the mist collector 10 with the opening 34 is provided. This makes use of an upper region of the extra space in the second modification. According to this modification, because air that has passed through the mist collector 10 is discharged toward above the housing 2, the air is less likely to directly hit a worker working around the machine tool. Thus, this prevents or suppresses discomfort to workers during operation of the mist collector 10. While a structure in which air is discharged upward has been presented in this modification, the design thereof can be changed in various manners by changing the orientation of the pipe 33.

[0060] FIG. 16 is a front view of an internal structure of a storage chamber according to a fourth modification. In this modification, the extra space formed in the second modification is eliminated, so that the storage chamber 5 and therefore the machine tool are made to be compact. The mist collector 10 and the first headstock 14 are arranged so that left ends thereof are substantially aligned and close to the side cover 2b.

[0061] FIG. 17 is a front view of an internal structure of a storage chamber according to a fifth modification. In this modification, the mist collector 10 is installed on a far and low side in the storage chamber 5. This makes use of a relatively plenty of space on the far side (at the back) of the first headstock 14 in the storage chamber 5. The table 42 is placed on the bed 3, and the mist collector 10 is placed on the table 42. The opening 34 is formed on a lower part of the side cover 2b to face the outlet 10b of the mist collector 10. According to this modification, the support pillar 40 of the embodiment described above can be omitted, which simplifies the structures and achieves space savings.

[0062] In a case where the mist collector 10 can be made more compact, the mist collector 10 may be placed on the near side of the storage chamber 5 and to the left of the first headstock 14. In other words, the mist collector 10 and the first headstock 14 may be arranged adjacent to each other in the axial direction.Other modifications

[0063] The present invention is not limited to the embodiment described above. For example, a machine tool according to an aspect of the present invention may have a partition with which a space above a base in a housing is separated into a machining chamber in which machining with a tool is performed and a storage chamber located adjacent to the machining chamber and accommodating a device, and may include: a coolant discharge part located in the machining chamber and configured to discharge a coolant during machining of a workpiece supported by a workpiece spindle; a mist collector located in the storage chamber; and a mist intake formed on the partition and being open toward the machining chamber. An outlet of the mist collector may be connected with an opening on a side face, a rear face, a front face, or a top face of the housing by a pipe, or the outlet of the mist collector may be in direct contact with the side face, the rear face, the front face, or the top face of the housing. In other words, the mist collector may be located in the storage chamber, so that the outlet of the mist collector is flush with an outer surface of the housing.

[0064] While an example of the storage chamber with a left workpiece spindle that is located on the left as viewed from a front door of a machine tool has been presented in the embodiment, the storage chamber is not limited to the example. As illustrated in FIG. 18, a mist collector may be provided in a storage chamber with a right workpiece spindle that is located on the right as viewed from a front door of a machine tool. In a manner similar to the embodiment, such a configuration also prevents significant protrusion of part of the mist collector from the housing as in conventional devices. In addition, the storage chamber is not limited to one accommodating part of a workpiece spindle, but may be a machine room or the like adjacent to the machining chamber and accommodating other devices such as a numerical controller (NC) or some devices of a coolant tank. Such a configuration also allows a mist collector to be provided in a space at the back of the machining chamber in a machine tool, for example, and thus prevents protrusion of part of the mist collector from the housing to the outside.

[0065] In the embodiment described above, an example in which the first workpiece spindle 20 and the second workpiece spindle 22 are provided as workpiece spindles and arranged to face each other along the axial direction has been presented. In a modification, a structure without the second workpiece spindle 22 may be adopted. A tailstock may be provided instead of the second workpiece spindle 22.

[0066] While the machine tool 1 has been described as being a turning center in the embodiment, the machine tool 1 may be a combined machine tool having the functions of a turning center and a machining center. The machine tool 1 may be a combined machine tool based on a turning center capable of milling and turning.

[0067] In a case where the machine tool 1 is a combined machine tool, a tool spindle is provided instead of the turret (tool rest). The tool spindle functions as a “tool holder” and is rotatably supported by a spindle head. The spindle head is driven in the X, Y, and Z directions by a movement mechanism. The combined machine tool further includes a tool storage and a tool changer. The tool storage includes a magazine for housing tools. The tool changer includes an automatic tool changer (ATC) to take out a tool from the tool storage and replace a tool on the tool spindle with the taken-out tool in accordance with a replacement instruction from the machining controller 102.

[0068] The present invention is not limited to the embodiments described above and modifications thereof, and any component thereof can be modified and embodied without departing from the scope of the invention. Components described in the embodiments and modifications can be combined as appropriate to form various embodiments. Some components may be omitted from the components presented in the embodiments and modifications.

[0069] This application claims priority from Japanese Patent Application No. 2024-153556 filed on September 6, 2024 and Japanese Patent Application No. 2025-041344 filed on March 14, 2025, the entire contents of which are hereby incorporated by reference herein.

Claims

1. A machine tool having a partition with which a space above a base in a housing is separated into a machining chamber in which machining with a tool is performed and a storage chamber in which a headstock is accommodated, the machine tool comprising: a workpiece spindle rotatably supported by the headstock and having a leading end exposed to the machining chamber; a coolant discharge part located in the machining chamber and configured to discharge a coolant during machining of a workpiece supported by the workpiece spindle; a mist collector located in a space above the headstock and having an outlet open on a side face of the housing; a mist intake formed on the partition and being open toward the machining chamber; and a pipe arranged in the storage chamber and connecting an inlet of the mist collector with the mist intake.

2. The machine tool according to claim 1, further comprising: a support pillar standing upright on the base in addition to the headstock in the storage chamber, wherein the mist collector is supported by the support pillar.

3. The machine tool according to claim 2, wherein the support pillar is located on a far side in a depth direction in the storage chamber, and wherein the mist collector is cantilevered and supported by the support pillar and located on a near side of the support pillar in the depth direction.

4. The machine tool according to claim 1 or 2, wherein the mist intake is located above the workpiece spindle exposed to the machining chamber.

5. The machine tool according to claim 4, wherein a cover that covers the mist intake from above to restrict direct entry of the coolant discharged from the coolant discharge part is provided on a side face of the partition in the machining chamber.

6. The machine tool according to claim 4, further comprising: a first headstock being the headstock; a first workpiece spindle being the workpiece spindle; a second workpiece spindle arranged to face the first workpiece spindle in the machining chamber; a second headstock located in the machining chamber, rotatably supporting the second workpiece spindle, and being movable in a direction in which the second workpiece spindle is moved toward or away from the first workpiece spindle; and a tool holder located on a far side of the second headstock in the depth direction in the machining chamber, wherein the mist intake is located on a near side in the depth direction of the machining chamber.

7. The machine tool according to claim 6, wherein the mist collector is located on a far side of the first headstock in the depth direction, and wherein the pipe is located above the first headstock.

8. The machine tool according to claim 7, wherein the inlet of the mist collector is at a position relatively higher than the mist intake.

9. The machine tool according to claim 2, wherein the mist collector is placed on a table on an upper end of the support pillar, wherein the table includes: a fixed table fixed to the support pillar; a movable table on which the mist collector is placed; and a sliding mechanism between the fixed table and the movable table, and wherein the movable table with the mist collector placed thereon is slidable to outside of the housing.

10. The machine tool according to claim 1, wherein the housing has an opening at a position corresponding to a position of the outlet of the mist collector, wherein the mist collector includes: a case having a flow passage connecting the inlet with the outlet; a fan located on the flow passage; a filter located near the outlet on the flow passage; and a hood attached to the case to surround the outlet, wherein the hood is attached to the case in a manner that the outlet is openable and closable, and wherein the filter is replaceable when the outlet is open.

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