JP5215061B2 - Dust-proof and waterproof structure of machine tool using waterproof sheet - Google Patents

Description

  The present invention relates to a dustproof and waterproof structure for a machine tool using a waterproof sheet.

  Machine tools usually have dustproof and waterproof measures such as covering each axis of the machine tool with bellows, but in ultra precision processing machines, bellows etc. may affect the operation of each axis. In some cases, only a simple dustproof and waterproof structure that does not affect the processing accuracy can be used. For example, Patent Document 1 discloses a splash guard that is covered with a single sheet including the spindle device and the X-axis and Y-axis guides that are driving mechanisms thereof. Further, in the splash guard, chips and cutting oil are hardly accumulated by making the sheet into a bag shape and putting air therein.

JP 2008-93763 A

  In an ultra-precision machine, a dust-proof and waterproof structure may be provided on each shaft for dust-proof and waterproof properties. However, the structure may be complicated and adversely affected, and the number of parts increases, resulting in an increase in cost. On the other hand, if it does not have a dustproof and waterproof structure, dust and liquid may enter the bearing directly, leading to failure.

  When the driving side and the fixed side of the spindle device or the like are covered with a single seamless sheet as in Patent Document 1, the stroke of the spindle device in the vertical and horizontal directions or in the horizontal and forward directions is limited. In order to secure the stroke, the sheet must have a considerable slack, and the possibility that the slack interferes with the main shaft increases. Patent Document 1 also discloses means for preventing air slack by sending air into the bag-type sheet. However, since air flows into the sheet and vibration occurs in the sheet and shaft, a machine that requires high accuracy is disclosed. It seems difficult to apply to machines.

  Accordingly, an object of the present invention is to provide a dustproof and waterproof structure capable of effectively partitioning a drive unit such as a spindle of a machine tool and a fixed unit such as a machine cover without affecting the drive accuracy of the spindle. .

In order to achieve the above object, the invention described in claim 1 is a dustproof and waterproof structure for a machine tool having a drive part and a fixed part, and is attached to the fixed part and a first flange attached to the drive part. has a bag-like form provided with no substantial gap between the second flange to be have a waterproof sheet for partitioning the machining area and machine internal area of the machine tool, the tarpaulin movable range of the drive unit Provided is a dustproof and waterproof structure for a machine tool using a waterproof sheet, characterized in that it has a dimension that always has a folded portion inside.

  According to a second aspect of the present invention, in the dustproof and waterproof structure according to the first aspect, the waterproof sheet is suspended from at least one position of the fixing portion of the machine tool, and the at least one position is a plurality of positions of the machine tool. Provided is a dustproof and waterproof structure in which the total load applied to the shafts is minimized or the load applied to a specific shaft is minimized.

  The invention according to claim 3 is the dustproof and waterproof structure according to claim 1 or 2, further comprising means for making the internal pressure of the machine internal area of the machine tool higher than the internal pressure of the processing area. provide.

  According to a fourth aspect of the present invention, there is provided the dustproof and waterproof structure according to the third aspect, wherein the means includes an exhaust of an air bearing provided in the machine interior area of the machine tool.

  Invention of Claim 5 is a dust-proof waterproof structure of any one of Claims 1-4, The joint of the said waterproof sheet is provided in the side part of this waterproof sheet, and it mutually overlaps in this joint Provided is a dustproof and waterproof structure in which a waterproof sheet located on the upper side of the waterproof sheet faces the processed area side at the joint.

  The invention according to claim 6 is the dustproof waterproof structure according to any one of claims 1 to 5, wherein a joint of the waterproof sheet is provided on an upper portion or a side portion of the waterproof sheet. provide.

  According to the dustproof waterproof structure including the waterproof sheet according to the present invention, the waterproof sheet that partitions the processing area of the machine tool and the machine internal area is configured to always have a folded portion within the movable range of the drive unit. The operating accuracy of the drive unit is not affected by the tension of the waterproof sheet. Therefore, the dustproof waterproof structure according to the present invention does not require a protection structure for each axis of the machine tool such as a bellows, and can be suitably used for a highly accurate machine tool.

  The tarpaulin is suspended from at least one position of the fixed part of the machine tool, and the total load applied to a plurality of axes of the machine tool is minimized or the load applied to a specific axis is minimized at the at least one position. By setting the position to be such that the weight of the sheet acts on the drive unit, it is possible to prevent the operation accuracy of the drive unit from being lowered.

  By having a means for making the internal pressure of the machine internal area of the machine tool higher than the internal pressure of the machining area, it is possible to more reliably prevent the machining fluid and the like from entering the machine internal area from the machining area. Further, as the means, by using the exhaust of the air bearing provided in the machine internal area of the machine tool, the cost can be reduced without providing any additional means.

  When forming a joint on the waterproof sheet, by providing the joint on the top or side of the waterproof sheet, it is possible to prevent the processing liquid or the like from entering the machine internal area by gravity. When the joint is provided on the side of the waterproof sheet, the waterproof sheet positioned on the upper side of the waterproof sheets overlapping each other at the joint faces the processing area side, so that the machine for processing liquid by gravity, etc. Prevention of entry into the internal area is more reliably achieved.

  FIG. 1 is an external view of a machine tool 10 including a dustproof and waterproof structure according to the present invention, and FIG. 2 is a schematic diagram showing a configuration of a drive shaft of the machine tool 10. The machine tool 10 guides the rotary shaft 12 to which a workpiece (not shown) can be attached, the Y-axis slide 14 that is a Y-axis drive unit that supports the rotary shaft 12, and the Y-axis slide 14 in the vertical direction (Y direction). A Y-axis guide 16, a Z-axis slide 18 that is a Z-axis drive unit that supports the Y-axis guide 16, and a Z-axis guide 20 that guides the Z-axis slide 18 in the rotation axis direction (Z direction). Although not shown, the machine tool 10 moves an X-axis slide and an X-axis slide in the X-axis direction as an X-axis drive unit for moving the rotary shaft 12 in the X direction perpendicular to both the Y direction and the Z direction. An X-axis guide for guiding may be further provided.

  As shown in FIG. 1, a machining area 22, which is a region for machining a workpiece attached to the rotary shaft 12, is surrounded by a machining area cover 24 so that machining fluid and the like are not scattered outside. Further, the machine tool 10 includes a machine fixing cover 26 that protects the slides and guides of the above-mentioned axes, and a waterproof sheet (hereinafter simply referred to as a sheet) that is attached to the machine fixing cover 26 so that machining fluid does not enter the slide and guide sides. 28).

  Hereinafter, the configuration of the waterproof sheet will be described in detail. FIG. 3 is a cross-sectional view (side cross-sectional view) of the machine tool 10 as viewed in the lateral direction (X direction), and FIG. 4 is a view of the waterproof sheet as viewed from substantially the front (Z direction). As described above, the waterproof sheet 28 prevents the machining fluid or the like in the machining area 22 from entering the slide and guide sides (hereinafter referred to as the machine interior area 30) of each axis of the machine tool. It is configured to partition the area 30. Specifically, the seat 28 has a first flange 32 attached to a movable part (for example, the rotating shaft 12) of the machine tool and a second flange 34 attached to a fixed part (for example, the machining area cover 24) of the machine tool. And it has a bag-like form provided without a substantial gap between the first flange and the second flange. The seat 28 is further dimensioned to have a folded portion 36, as shown in FIG. 3, rather than being tightly stretched between the first flange 32 and the second flange 34. The folded portion is always formed in each axis of the machine tool, that is, in the stroke of the movable part (within the operating range).

  Specifically, as shown in FIGS. 5A to 5C, the movable portion (the rotating shaft 12 in the illustrated example) to which the first flange 32 is attached is positioned at the forefront (processing area side). In the state (Fig. 5 (a)), the state located in the rearmost (machine internal side) (Fig. 5 (c)) and the state located in the middle (Fig. 5 (b)) Also have some folded portion 36. According to such a configuration, the waterproof sheet is not strongly stretched regardless of the position of the movable part, so that a large load is not applied to the movable part such as the rotating shaft. Therefore, the present invention can also be applied to an ultraprecision machine. In addition, by using a bag-type waterproof sheet, it is possible to operate without applying an excessive load even when the driving side moves in the forward / backward, up / down, or left / right direction.

  The material of the waterproof sheet is preferably a material having high water repellency, a low coefficient of friction, and sufficient flexibility so as to ensure the operation performance of the machine tool. Specifically, Nabel 10 (registered trademark), Hypalon (registered trademark) sheet, urethane sheet, and the like available from Nabel Co., Ltd. are preferable.

  Further, as shown in FIG. 4, by providing round corners on the outer periphery of the first flange 32 and the inner periphery of the second flange 34, the waterproof sheet is caught on the corner of the flange or rubbed and damaged by the corner. Can be prevented. Alternatively, the entire flange may be circular or elliptical.

  If the waterproof sheet is relatively large, the weight of the sheet may act on the rotating shaft even if the sheet has a folded portion, which may affect the operation accuracy of the rotating shaft. Therefore, as shown in FIG. 6, the seat 28 is hung from the fixed side (fixed cover 26 in the illustrated example) with a stretchable rope or string 38 so that at least a part of its own weight is supported on the fixed side. preferable. Here, the position 40 on the fixed cover on which the seat 28 is suspended is determined by searching in advance for a position where the load on each axis is minimized. Specifically, it may be a position where the total load applied to a plurality or all of the axes is minimized, or a position where the load applied to a specific axis is minimized. The load applied to each axis can be measured using a known load meter or the like. The hanging position 40 is not limited to one.

  Since the waterproof sheet according to the present invention usually has a three-dimensional shape, a seam (a part where two sheets partially overlap) is always generated on a part of the sheet. In the present invention, in order to prevent the machining fluid or the like from entering the inside of the machine due to gravity, as shown in FIG. 7, the joint 42 generated in the sheet 28 is located at an upper portion or a side portion of the sheet, that is, a portion other than the lower portion. Provided. Specifically, when the sheet is substantially rectangular, the joint 42 is provided on the upper side 44 or the side side 46, and is not provided on the bottom side 48. By providing the seam other than the lower side of the bag-type sheet, the possibility that the processing liquid and dust enter the machine from the seam can be greatly reduced. When the joint 40 is provided on the side, as shown in FIG. 8, when the upper sheet 28 a and the lower sheet 28 form a joint 42, the upper sheet 28 a The joint is configured to face the processing area 24 side.

  By making the air pressure inside the machine higher than the machining area side, it is also possible to suppress the entry of the machining fluid into the machine inside area. By making the machine internal area 30 a sealed structure and making the internal pressure of the machine internal area higher than the internal pressure of the machining area 22, entry of machining fluid or the like from the above-mentioned joints or gaps between the machining area (not shown) and the machine internal area is prevented. can do. Note that the machine internal area 30 may not have a strictly sealed structure as long as a constant internal pressure difference can be obtained between the machine internal area 30 and the machining area 22, that is, there may be a slight gap. Further, as shown in FIG. 9, when the pressure on the machine internal area 30 side is increased, the pressure as shown by the arrow acts on the sheet 28 to deform the sheet. Specifically, the folded portion 36 is moved to the processing area side. It becomes convex and the entire sheet is somewhat stretched. When the sheet is deformed in this way, it is possible to prevent the processing liquid or the like from accumulating at the lower part of the sheet. However, the tension of the sheet, that is, the pressure difference between the machine inner area and the processing area 22 is set to such an extent that the tension of the sheet does not affect the operation accuracy of the driving unit such as the rotating shaft.

  As a means for increasing the pressure in the machine internal area 30, various methods such as supplying air from a nozzle (not shown) provided in the area 30 can be considered, but an air bearing is used for the bearing of each shaft. In this case, the internal pressure of the machine internal area 30 can be increased without using a means such as a nozzle by utilizing the exhaust of the air bearing.

1 is an external view of a machine tool having a dustproof and waterproof structure according to the present invention. It is the schematic which shows the structure of the drive part of the machine tool of FIG. It is sectional drawing which looked at the machine tool in the horizontal direction. It is a figure which shows a waterproof sheet with the flange to which this sheet | seat is attached. (A) Side sectional view showing a state in which the drive unit is located closest to the machining area side, (b) Side cross section showing a state in which the drive unit is located substantially in the middle between the machining area and the machine internal area It is a figure, (c) It is a sectional side view which shows the state in which the drive part is located in the machine interior area side most. It is a figure which shows the form which suspended the waterproof sheet with the rope. It is a figure which shows the example which formed the joint in the waterproof sheet. It is a figure which shows the sheet | seat structural example in the case of forming a joint in the side part of a waterproof sheet. It is a figure which shows the state which made the internal pressure of the machine internal area high.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Machine tool 12 Rotating shaft 22 Processing area 28 Waterproof sheet 30 Machine internal area 36 Turn-up part 38 Rope 42 Joint

Claims (6)

A dustproof and waterproof structure for a machine tool having a drive part and a fixed part,
It has a bag-like form provided without a substantial gap between the first flange attached to the drive part and the second flange attached to the fixed part, and partitions the processing area of the machine tool from the machine internal area. Has a tarpaulin,
The dustproof waterproof structure for a machine tool using the waterproof sheet, characterized in that the waterproof sheet has a size that always has a folded portion within a movable range of the drive unit.   The waterproof sheet is hung from at least one position of the fixed part of the machine tool, and the at least one position is a load that is applied to a specific axis that minimizes the total load applied to a plurality of axes of the machine tool. The dust-proof and waterproof structure according to claim 1, wherein the position is such that is minimized.   The dustproof and waterproof structure according to claim 1 or 2, further comprising means for making an internal pressure of the machine internal area of the machine tool higher than an internal pressure of the processing area.   The dustproof and waterproof structure according to claim 3, wherein the means includes an exhaust of an air bearing provided in the machine internal area of the machine tool.   The joint of the waterproof sheet is provided on a side portion of the waterproof sheet, and the waterproof sheet located on the upper side of the waterproof sheets overlapping each other at the joint faces the processing area side at the joint. The dustproof and waterproof structure according to any one of -4.   The dustproof waterproof structure according to any one of claims 1 to 4, wherein a joint of the waterproof sheet is provided on an upper part or a side part of the waterproof sheet.

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