JP2001062667A - Machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a machine tool to be excellent in tips collecting and discharging performance. SOLUTION: This machine tool applies desired machining on a work through relative movement of a work and a tool in the three directions of an X-axis, an Y-axis, and a Z-axis. In this case, a trough 53 formed of a sheet member is situated in the longitudinal direction of the central part of a bed 3 throughout a range extending from the front part of a bed to the rear part thereof with a space formed between a bed 3 and the trough. A table 5 is moved along guide rails 21 longitudinally in a state to be stride the trough 53 and inclination covers 49 to cover the guide rails are situated throughout a whole region of longitudinal movement of the table 5 with the inclination covers inclined in the shape of a valley from the right and the left toward the trough 53, and a chip conveyor 65 is provided to discharge chips dropping in the trough 5 to the outside of a machine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine tool for performing desired processing on a workpiece by relatively moving the workpiece and a tool in three directions of X, Y, and Z axes. Related to machine tools.

[0002]

2. Description of the Related Art In a machine tool, one of the most important themes is how to efficiently discharge a large amount of chips generated when machining a workpiece out of the apparatus. Research and development. For example, Tokuho 6
JP-A-28835 and JP-A-58-93437 propose a structure in which troughs are provided on both sides of a table and chips are individually removed by the troughs on each side. That is,
FIG. 4 of Japanese Patent Publication No. Hei 6-28835 discloses a vertical machining center provided with tables moving in the X and Y axis directions, troughs provided on both sides of the table to receive chips, and chips in each trough. A configuration in which chips are discharged to the outside of the machine by a discharge means is disclosed. In addition, 58-934
In FIG. 3 of Japanese Patent Publication No. 37-304, a table which moves in the Z-axis direction is provided in a horizontal machining center, troughs are provided on both sides of the table to receive chips, and chip discharge means using fluid in each trough is provided. A configuration for discharging chips is disclosed.

[0003]

However, in the above two conventional structures, the troughs are dispersed in two places, and each of the troughs requires a chip discharging means, which complicates the structure. Also, the width of each trough is as small as dividing the dimension allocated for troughs into two, and the width of each trough becomes narrower when trying to make the whole machine compact, so that each trough has chips. (A bird's nest-like chip pool) is likely to be formed. In addition, since chips and cutting oil generated during machining retain cutting heat, there is also a problem that the bed of the machine tool is thermally deformed.

[0004] Therefore, an object of the present invention is to provide a compact machine tool which does not involve such inconvenience and has excellent performance for collecting and discharging chips and the like.

[0005]

According to a first aspect of the present invention, there is provided a machine tool for performing desired processing on a workpiece by relatively moving the workpiece and a tool in three directions of X, Y and Z axes. A bed serving as a base of the machine, and a column that moves along a guide provided in a lateral direction at a rear portion of the bed,
A spindle head that moves along a guide provided in the vertical direction at the front of the column and has a spindle for mounting the tool at the tip, and a front to rear portion of the bed in the front-rear direction of the center of the bed. And a concave trough made of a thin plate member attached with a space between the bed and the bed, and the work is placed on the bed on both left and right sides of the concave trough in the front-rear direction. A table moving across the concave trough along the guide provided on the table, and a table provided to cover the guide for the longitudinal movement of the table, and a valley from the left and right toward the concave trough. Inclined cover having an opening for chip falling over the entire area of the table moving in the front-rear direction, and chip discharging means provided in the concave trough and discharging the dropped chip outside the machine. And gist machine tool provided with the.

Preferably, a feeding means for moving the table in the front-rear direction is attached to the rear side of the table, and the feeding means for moving in the front-rear direction does not protrude to the front side of the table.

[0007]

[Function] A wide trough is provided at the center of the bed below the table, and a valley-shaped inclined cover inclined toward the trough is provided. Therefore, when machining a workpiece on the table despite its simple and simple structure. Chips falling from the opening of the inclined cover surely fall directly into the trough or along the inclined cover.

[0008] Since the trough is attached to the bed with a space, it is difficult for the heat of chips and cutting fluid to be directly conducted to the bed.

In the case where the feeding means for moving the table in the front-rear direction is attached to the rear side of the table, chips are provided at the rear side of the table through the gap space between the cover of the feeding means and the inclined cover, and the inside of the trough. At the front of the table, there is a large space corresponding to the trough, and the chips fall into the trough without being caught at all.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 is a right side view showing the overall schematic configuration of the machine tool according to one embodiment of the present invention. The machine tool 1 is a vertical machining center that relatively moves a work and a tool in three orthogonal directions of X, Y, and Z axes and performs desired machining (boring, milling, drilling, grinding, and the like) on the work. For convenience of explanation, the front cover and the like have been removed from the figure.

A large bed 3 serving as a base of the illustrated machining center 1 is formed by, for example, a casting method in which a molten metal that has been heated and melted is poured into a mold and cooled and solidified, and has an L-shape when viewed from the side. The bed core is formed by so-called lightening molding (frame structure by ribs) for weight reduction and high strength. The bed 3 incorporates a chip collecting / discharging structure which is a main part of the present invention, and details thereof will be described later.

A table 5 for detachably fixing a work (not shown) is provided at a front portion (operator side) of the bed, and is provided at a rear portion of the bed which is one step higher than the bed front portion. A column 9 (moving body) having a spindle head 7 is disposed on the upper side. The column 9 is supported movably in the bed left-right direction (X-axis direction) as viewed from the worker side, and the spindle head 7 moves in the vertical direction (Z-axis direction) with respect to the column standing surface on the worker side. Supported as possible. A vertical spindle 11 is rotatably arranged in the spindle head, and a lower end of the spindle is partially exposed for mounting a tool holder holding a tool.

An accessory device 15 including a control device and a lubricating oil supply device is disposed on the back side of the bed, and a machining fluid tank 17 for storing a machining fluid collected from the bed 3 is provided below the accessory device 15. A receiving cover 19 for guiding the working fluid into the working fluid tank is provided near the upper side. Next, with reference to FIGS. 1 and 2, the internal structure of a bed which is a main part of the present invention will be described in detail.

The work fixing table 5 is composed of a pair of mutually parallel Y-axis guide rails 21 fixed to the upper surface of the front part of the bed (operator side) and extending in the bed front-rear direction (Y-axis direction). Through a guide device basically composed of four (only two can be seen in FIG. 1) linear motion bearings 23 fixed to the table bottom surface engaged with the Y-axis guide rail 21,
It is supported movably in the Y-axis direction (bed front-back direction).

At the approximate center of the rear surface of the table 5, a nut bracket 27 projecting rearward is attached, and at the tip of the nut bracket, a feed screw nut 29 is attached. The feed screw nut 29 is attached to both Y-axis guide rails. It is screwed to a feed screw shaft 31 for driving the table, which is arranged in parallel on the upper side between 21. The feed screw shaft 31 is rotatably supported by a support bearing 37 mounted on a motor bracket 35 fixed to the rear side of the bed and a support bearing 41 mounted on a bracket 39 fixed on the front side of the bed. The end of the feed screw shaft on the rear side of the bed is connected to the motor shaft of the Y-axis feed motor 45 for driving the table attached to the motor bracket 35 so as to be integrally rotatable. The nut bracket 27 includes a feed screw nut 29 and a feed screw shaft 31 located on the front side of the bed with respect to the feed screw nut 29.
The parts are covered in a chevron, and serve as a cover so that chips and cutting fluid are not directly applied to them. It is to be noted that, although not shown, the nut bracket may be formed in a half-cylindrical cylindrical shape or a cylindrical or rectangular cylindrical shape, although not shown.

On both sides of the rear surface of the table, so-called telescopic covers (expandable covers) 49 that can expand and contract in the front-back direction of the bed as the table moves are provided so as to cover the Y-axis guide rails 21 from above. The telescopic cover 49 is arranged so as to exhibit a valley shape (in other words, an inverted C shape when viewed from the front or rear of the table) such that the telescopic cover 49 is inclined toward the center and becomes narrower.

Similarly, on both sides of the front surface of the table, telescopic covers 49 are provided so as to cover the Y-axis guide rails 21 from above, and the telescopic covers 49 on both sides are inclined toward the center and become narrower. It is arranged and arranged to exhibit such a valley shape (in other words, an inverted C-shape viewed from the front or rear of the table). The bottom of the valley has an opening so that chips and machining fluid fall downward from the opening. This telescopic cover 49 is an inclined cover referred to in the claims.

The bed surface portion of the bed 3 which is sandwiched between the two Y-axis guide rails 21 and forms a bottom surface of a concave groove portion extending in the Y-axis direction, which is one step lower, has a U-shaped cross section opened upward. A trough 53 made of a thin metal plate is mounted via a mounting seat (plate) 55 so as to have a predetermined gap (space) with respect to a bed surface portion mainly for heat insulation. At the front and rear ends of the trough 53 in the Y-axis direction,
a and 53b are provided, and a bottom surface opening 53c is provided in the bottom portion of the rear portion of the trough so that the working fluid can be dropped and collected into the working fluid tank 17 immediately below the trough.

Inside the trough 53, an endless chain 61 is provided.
A chip conveyor (a chip discharging means) 65 having a scraper (a scraping plate) 63 attached thereto at a predetermined pitch is disposed thereon, and the chips and the working fluid that have fallen into the trough 53 are forcibly scraped out and the bottom surface of the trough 53 is formed. It is configured such that it can be dropped into the machining liquid tank 17 from the opening 53c. In the vertical machining center 1 according to the present embodiment having the above-described configuration, a single wide trough 53 is disposed below the center of the table 5, and the valley along the moving direction (Y-axis direction) of the table 5 is provided. Since a simple and simple configuration in which the inclined cover (telescopic cover 49) is arranged so as to form a portion is employed, chips generated at the time of machining the work can be directly or trough-shaped into the trough 53 directly below the table. It can be reliably dropped and collected along. That is, on the front side of the table, there is a large space (entrance width dimension A of the trough 53) defined by the trough-shaped telescopic cover 49 above the trough 53, and the chips are
It can fall into the trough 53 without being caught at all. On the other hand, on the rear side of the table, only the space occupied by the nut bracket (angle-shaped cover) 27 that supports and covers the feed screw nut 29 is subtracted from the space corresponding to the large space on the front side of the table. Although only the side space (total 2B of the width of the entrance width of the trough 53) is free, it is still enough as a space for the chips to pass, and the angle of the nut bracket 27 helps the table. As on the front side, the chips can fall into the trough 53 without stress. Thereby, it is possible to eliminate chipping of chips and formation of chip piles (bird's nest-like chip accumulation).

Further, in this embodiment, since only one chip conveyor (chip discharging means) needs to be provided, compared with a conventional complicated structure in which a plurality of troughs are provided with a plurality of chip discharging means. Very reasonable and economical. As means for forcibly discharging chips in the trough, instead of a scraper-type device as in the above-described embodiment, although not shown, a processing liquid is ejected to the trough and chips are pushed out by the pressure and a screw conveyor type is used. A device can be employed.

Further, in the present embodiment, the trough 53
Is formed separately from the bed 3, and the trough 53 is formed with high heat dissipation by bending a thin plate member.
Is configured to be attached to the bed 3 with a gap (insulated space), so that the heat of the chips and the cutting fluid is less likely to be directly transmitted to the bed 3. Inconveniences such as thermal deformation of the bed 3 resulting from deterioration of the processing accuracy can be reduced or eliminated.

By the way, the vertical machining center 1 of the embodiment shown in FIGS. 1 and 2 has an offset structure in which the feed screw shaft 31 (Y-axis direction feed means) is always located on the rear side of the table. On the other hand, although not shown,
It is also possible to have a configuration in which the feed screw shaft penetrates (crosses) the lower part of the table and extends forward and backward of the table. In this embodiment, the cover is attached to the front side of the table for the same purpose as the nut bracket on the rear side of the table,
The chips can be reliably dropped and collected in the trough without being caught, as in the rear side of the table.

Next, as a second embodiment, a case where the present invention is applied to a horizontal machining center will be described with reference to FIG. The main differences from the vertical machining center in FIG.
A column 9 is provided that can move the rear part of the bed 3 in the left-right direction (X-axis direction), and the spindle head 7 is movable in the column 9 in the vertical Y-axis direction. The main shaft 11 is horizontally supported, and the bed 3
The upper front part is provided with a table 5 which is movable in the front and rear Z-axis directions and is indexable. Below the table 5, a telescopic cover and a trough are provided, and the structure in which chips dropped into the trough are discharged to the working fluid tank by the chip conveyor is the same as in the above-described embodiment, and thus the detailed description is omitted. As described above, the present invention is applied not only to a machine tool having a vertical spindle but also to a machine tool having a horizontal spindle.

[0024]

As described above, according to the present invention, one of the central portions of the bed is provided in the front-to-rear direction from the front to the rear just below the inclined cover below the table, and is wider than the opening width of the inclined cover. Since a machine tool comprising a chip processing mechanism is provided by a trough, a valley-shaped inclined cover for guiding chips to fall into the trough, and one chip discharge means provided in the trough, a simple machine tool is provided. Despite the configuration, it is possible to reliably collect and discharge chips, and to realize a compact machine tool. Since the trough is attached with a space to the bed,
It is difficult for the heat of chips and cutting fluid to be conducted directly to the bed.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a bed of a machine tool according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the bed taken along the line II-II in FIG. 1 and viewed from a direction of an arrow.

FIG. 3 is a right side view illustrating an overall schematic configuration of the machine tool according to the embodiment of FIG. 1;

FIG. 4 is a right side view illustrating an overall schematic configuration of a machine tool according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Vertical machining center 3 ... Bed 5 ... Table 17 ... Processing fluid tank 21 ... Y-axis guide rail 27 ... Nut bracket 29 ... Feed screw nut 31 ... Feed screw shaft 49 ... Telescopic cover 53 ... Trough 55 ... Mounting seat 65 ... Chip conveyor

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideyuki Kashiwagi 3560-1, Katsuyamamura, Minamitsuru-gun, Yamanashi Prefecture Inside Makino Milling Machinery Co., Ltd. Inside milling mill

Claims (2)

[Claims] 1. A machine tool for performing desired processing on a work by relatively moving a work and a tool in three directions of X, Y, and Z axes, comprising: a bed serving as a base of the machine; A column that moves along a guide provided in the left and right direction at the rear, and a spindle head that moves along a guide provided in the vertical direction at the front of the column, and has a spindle for mounting the tool at the tip. A concave trough made of a thin plate member provided from the front to the rear of the bed in the front-rear direction of the center of the bed and attached with a space between the bed and the work; And a table that moves across the concave trough along a guide provided in the front-rear direction on the bed on both the left and right sides of the concave trough; and covers a guide for the front-rear movement of the table. Provided An inclined cover inclined in a valley shape from left and right toward the concave trough, and having an opening for chip dropping over the entire region of the table in the front-rear direction; and provided in the concave trough. And a chip discharging means for discharging the dropped chips to the outside of the machine. 2. The machine tool according to claim 1, wherein feed means for moving the table in the front-rear direction is attached to the rear side of the table, and feed means for moving in the front-rear direction does not project from the front side of the table.