JP2004216506A - Automatic positioning device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for highly accurately and automatically positioning a movable block such as a work pallet on a table. <P>SOLUTION: An annular central pillar 12 is protruded upward from a reference block 2 on a fixed side and a plurality of wedge faces 13 are provided on the outer periphery of the central pillar 12 in peripherally spaced relation. On the outside of the central pillar 12, a circular plug 15 is arranged which is inserted into a positioning hole 5 of the movable block 3. On a peripheral wall 15a of the circular plug 15, a plurality of thrusting tools 17 are supported to be movable in the radial direction in peripherally spaced relation. Each of the thrusting tools 17 can be put in wedge engagement with the wedge face 13 and reset inward to the radial direction. An output member 21 is inserted into the central pillar 12 so as to be movable up and down and the output member 21 is connected at its upper part to the circular plug 15. A lock spring 34 in the reference block 2 moves the circular plug 15 down via the output member 21 and pressure oil in a release chamber 35 moves the circular plug 15 up via the output member 21. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for automatically positioning a movable block such as a work pallet on a reference block such as a table of a machine tool.
[0002]
[Prior art]
In general, this type of positioning device is configured such that a circular positioning hole opened in a supported surface of a movable block is fitted to a plug protruding from a support surface of a reference block (for example, Japan -See JP-A-57-27640).
[0003]
[Problems to be solved by the invention]
In the above prior art, it is necessary to provide a predetermined fitting gap between the positioning hole and the plug in order to smoothly fit both of the positioning hole and the plug. For this reason, the positioning accuracy is reduced by the fitting gap.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a device which can automatically and accurately position.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, as shown in FIGS. 1A and 1B or FIGS. 4A and 4B, an automatic positioning device is configured as follows.
An annular center column 12 is protruded from the reference block 2 on the fixed side in the distal direction, and the center column 12 is fixed to the reference block 2. A wedge surface 13 is provided on the outer periphery of the above-mentioned center column 12 so as to approach the axis as it goes toward the above-mentioned tip. An annular plug 15 to be inserted into the positioning hole 5 of the movable block 3 is arranged outside the above-mentioned center column 12. The plurality of pressing tools 17 are supported on the peripheral wall 15a of the annular plug 15 at a distance in the circumferential direction so as to be movable in the radial direction. Each of the pressing members 17 is wedge-engaged with the wedge surface 13, and each of the pressing members 17 is configured to be able to return inward in the radial direction by the return means 18. An output member 21 is inserted into the shaft 12 so as to be movable in the axial direction, and a distal end of the output member 21 is connected to the annular plug 15. A lock unit 31 and a release unit 32 are provided in the reference block 2. The locking means 31 locks the annular plug 15 in the proximal direction via the output member 21. The release means 32 releases the annular plug 15 via the output member 21 in the distal direction.
[0005]
The first aspect of the present invention has the following operational effects.
When positioning the movable block on the reference block, first, the positioning hole of the movable block is fitted into the annular plug (and pressing tool) of the reference block, and then the locking means is connected to the movable block via the output member. Is driven in the proximal direction. Then, the plurality of pressing tools supported by the annular plug directly or indirectly wedge-engage with the wedge surface of the center column and move outward in the radial direction. Adhere to the hole. For this reason, the above-mentioned movable block is restrained by the above-mentioned center pillar via the above-mentioned plurality of press tools. At the same time, the output member presses the movable block against the reference block via the pressed pressing tool.
On the other hand, when the movable block in the locked state is released, the annular plug may be driven in the distal direction by the release means via the output member. Then, the wedge engagement between the wedge surface and the pressing tool is released, and the return means moves the pressing tool radially inward. This releases the close contact between the pressing tool and the positioning hole. Thereafter, the movable block may be separated from the reference block.
[0006]
According to the first aspect of the present invention, after the positioning hole and the annular plug are fitted, the fitting gap can be eliminated by the pressing tool. Therefore, it is possible to achieve both smooth fitting of these positioning holes and the annular plug and positioning with high precision. In addition, since the lock means and the release means are provided in the reference block, positioning and release of the position can be automatically performed, and foreign matters such as chips and dust enter the inside of the lock means and the release means. Can be prevented.
At the time of the lock drive, the output member presses the movable block to the reference block via the annular plug and the pressing tool, so that a dedicated clamping means can be omitted as necessary. It is.
[0007]
As described in the second aspect of the present invention, in the first aspect of the present invention, the inner space of the peripheral wall 15a of the annular plug 15 is covered by a ceiling wall 15b in a hermetically sealed manner. It is preferable that the base of the above-mentioned peripheral wall 15a is supported in a hermetically movable manner in the axial direction.
According to the second aspect of the present invention, since the inner space of the annular plug can be kept in a sealed state, foreign matter in the atmosphere can be prevented from entering between the engagement surface of the pressing tool and the wedge surface. Can be prevented.
[0008]
As shown in the third aspect of the present invention, it is preferable that a plurality of the wedge surfaces 13 are provided in the center column 12 at intervals in a circumferential direction. In this case, the pressing tool can be moved radially outward with high precision by the wedge surface.
[0009]
According to a fourth aspect of the present invention, in the third aspect of the present invention, a plurality of inclined grooves 19 are provided at intervals in the circumferential direction on the center pillar 12, and the bottom wall of the inclined grooves 19 It is preferable to form the wedge surface 13 described above. In this case, the pressing tool can be moved to the outside in the radial direction with higher accuracy by the wedge surface.
[0010]
According to a fifth aspect of the present invention, in the fourth aspect of the present invention, it is preferable that the return means 18 be formed by a fitting structure between the peripheral wall of the inclined groove 19 and the pressing tool 17. . In this case, both the simple construction of the return means and the reliable return operation can be achieved.
[0011]
According to a sixth aspect of the present invention, in the first or second aspect of the invention, when the wedge surface 13 is formed by a tapered outer peripheral surface, the wedge surface 13 can be simply configured.
[0012]
As shown in the seventh aspect of the present invention, it is preferable to add the following configuration to any one of the first to sixth aspects of the present invention.
A cleaning fluid supply port 40 is provided in the reference block 2, and a cleaning fluid discharge port 41 is formed by a fitting gap between the peripheral wall 15 a of the annular plug 15 and the pressing tool 17. 41 communicates with the supply port 40 described above.
In this case, since the above-mentioned fitting gap can be automatically cleaned, the above-mentioned presser moves smoothly with high precision.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
1A, 1B and 2 show a first embodiment of the present invention.
FIG. 1A is a cross-sectional view of the automatic positioning device when viewed from an elevation. FIG. 1B is a plan view of FIG. 1A described above. FIG. 2 is a cross-sectional view of a pressing tool described later.
[0014]
In this embodiment, a base plate 2 which is a reference block is placed on a table 1 of a machine tool, and a supported surface 3a of a work pallet 3 which is a movable block is received on a support surface 2a of the base plate 2. The work pallet 3 is arranged so as to be centered.
[0015]
A plurality of circular positioning holes 5 are opened in the supported surface 3a of the work pallet 3. A plug means 6 is provided on the base plate 2 corresponding to each positioning hole 5. Here, only one set of the plurality of sets of positioning holes 5 and plug means 6 is shown.
[0016]
The plug means 6 is configured as follows.
A mounting hole 8 is formed in the base plate 2, a datum block 9 is precisely fitted into the mounting hole 8, and a flange 9 a of the block 9 is fixed to a peripheral wall of the mounting hole 8 by four fastening bolts 10. You. An annular shaft 12 protrudes upward (toward the tip) from the block 9 described above. The axis of the shaft 12 is substantially the same as the axis of the mounting hole 8. The upper surface of the flange 9a constitutes the support surface 2a described above.
As will be described later, three wedge surfaces 13 are provided on the outer circumference of the above-mentioned center column 12 at substantially equal intervals in the circumferential direction, approaching the above-mentioned axis as going upward.
[0017]
An annular plug 15 inserted into the positioning hole 5 is arranged on the outer periphery of the above-mentioned center column 12. The annular plug 15 has a peripheral wall 15a and a ceiling wall 15b. Here, the inner space of the peripheral wall 15a is covered in a hermetically sealed manner by the ceiling wall 15b. The lower portion of the peripheral wall 15a is supported on the outer peripheral surface of the center column 12 via a sealing member (or a scraper) 16 so as to be vertically movable and hermetically sealed.
[0018]
Three pressing members 17 are supported on the peripheral wall 15a of the annular plug 15 at a distance in the circumferential direction so as to be movable in the radial direction, and each pressing member 17 is wedge-engaged with the wedge surface 13. is there.
Further, each of the pressing members 17 is configured to be able to return inward in the radial direction by the return means 18. More specifically, the above-mentioned shaft 12 is provided with three inclined grooves 19 at intervals in the circumferential direction. Each inclined groove 19 is formed in a V-shape in a cross-sectional view, and the wedge surface 13 is formed on a bottom wall thereof. The return means 18 is constituted by a fitting structure between the peripheral wall of the inclined groove 19 and the pressing tool 17.
[0019]
An output member 21 is inserted into the center column 12 so as to be vertically movable. The output member 21 includes a piston 22 hermetically inserted below the datum block 9, and a piston rod 23 projecting upward from the piston 22. Above the piston rod 23, the ceiling wall 15b of the annular plug 15 is screwed tightly.
In addition, the annular plug 15 is prevented from rotating around the axis by the guide pin 25 fitted to the ceiling wall 15b.
[0020]
Locking means 31 and release means 32 are provided in the block 9. The lock means 31 includes a lock spring 34 mounted on a lock chamber 33 above the piston 22 and the piston 22. Here, the lock spring 34 is constituted by a plurality of disc springs. The release means 32 includes a hydraulic release chamber 35 formed below the piston 22 and the piston 22. A pressure oil supply / discharge port 36 is communicated with the release chamber 35.
[0021]
Further, a supply port 40 for compressed air for cleaning is provided in the base plate 2. The fitting gap between the peripheral wall 15a of the annular plug 15 and the pressing member 17 forms a discharge port 41 for compressed air for cleaning. The supply port 40 passes through the horizontal path 42 in the datum block 9, the vertical path 43 and the horizontal through-hole 44 of the piston rod 23, and the lower space of the ceiling wall 15 b in this order. It is communicated with the exit 41.
[0022]
The automatic positioning device described above operates as follows.
In the release state of FIG. 1A (and FIG. 2), pressure oil is supplied to the release chamber 35. As a result, the piston 22 raises the piston rod 23 and the annular plug 15 against the urging force of the lock spring 34, and the pressing tool 17 moves radially inward along the inclined groove 19. It is moving towards.
[0023]
When positioning the work pallet 3 on the base plate 2, first, as shown in FIG. 1A, the work pallet 3 is lowered in the release state to make the positioning holes 5 into the annular plug 15 and the 3. The work pallet 3 is received in the datum block 9 by fitting the two pressing members 17 with a predetermined gap therebetween.
At the time of the fitting, the compressed air discharged from the discharge port 41 cleans the positioning hole 5.
[0024]
Next, the pressure oil in the release chamber 35 is discharged. Then, the piston 22 strongly lowers the annular plug 15 by the urging force of the rock spring 34. Then, each of the pressing members 17 supported by the annular plug 15 is wedge-engaged with the wedge surface 13 of the center column 12. As a result, the three pressing members 17 move outward in the radial direction, and the pressing surfaces 17a of the respective pressing members 17 strongly adhere to the positioning holes 5.
At the same time, the piston 22 pulls down the work pallet 3 via the annular plug 15 and the pressing tool 17, so that the supported surface 3a of the work pallet 3 is supported by the support plate 3 of the base plate 2. It is pressed against the surface 2a. Thereafter, the work pallet 3 is strongly pressed against the base plate 2 by a clamp means (not shown).
[0025]
When switching from the locked state to the released state, first, the clamped state of the clamping means (not shown) is released, and then the pressurized oil is supplied to the release chamber 35 as described above. As a result, the piston 22 raises the annular plug 15, the pressing tool 17 moves radially inward along the inclined groove 19, and the locked state is released. Thereafter, the work pallet 3 is raised.
[0026]
When the pulling force of the pressing tool 17 at the time of the lock driving is set to a sufficiently large value, the clamp means (not shown) can be omitted.
In the illustrated release state, the pressing surface 17a of the pressing tool 17 protrudes from the outer peripheral surface of the annular plug 15, but instead, the pressing surface 17a is 15 may be located more inward than the outer peripheral surface.
[0027]
FIG. 3 is a view showing a modification and is similar to FIG. 2 described above. In this case, the inclined groove 19 is formed in a T-shape in a cross-sectional view, and the pressing tool 17 is fitted into the inclined groove 19. As in the case of FIG. 2, the return means 18 is formed by the fitting structure, and the wedge surface 13 is formed on the bottom wall of the inclined groove 19.
[0028]
4A and 4B show a second embodiment. 4A is a view similar to FIG. 1A, and FIG. 4B is a view similar to FIG. In the second embodiment, members similar to those of the first embodiment are given the same reference numerals in principle.
[0029]
The second embodiment is different from the first embodiment in the following structure.
The wedge surface 13 is constituted by a tapered outer peripheral surface. The pressing tool 17 is in contact with the tapered wedge surface 13. Here, the contact surface of the pressing tool 17 is formed by a flat surface, but may be formed in an arc shape in a cross-sectional view. The return means 18 for returning the pressing tool 17 inward in the radial direction is constituted by a rod-shaped spring. As shown in FIG. 4B, the rod-shaped return means 18 is inserted into the through hole 48 of the pressing tool 17.
Further, the lock chamber 33 is communicated with another pressure oil supply / discharge port 49, and the lock means 31 is configured as a hydraulic lock type.
[0030]
The above-described first embodiment and second embodiment and each modified example can be further modified as follows.
The pressing tool 17 may be indirectly engaged via another member instead of directly engaging the wedge surface 13. Instead of providing the illustrated three pressing tools 17, two pressing tools 17 may be provided, or four or more pressing tools 17 may be provided.
[0031]
The support surface 2 a may be provided on the base plate 2 instead of being provided on the upper surface of the flange 9 a of the datum block 9.
The center column 12 and the datum block 9 may be formed separately instead of being formed integrally. In this case, the center column 12 may be firmly fixed to the datum block 9 by bolting or screwing.
Further, the datum block 9 and the base plate 2 may be integrally formed instead of being formed separately.
[0032]
A hydraulic lock and a spring release type may be used instead of the spring lock and a hydraulic release type of FIG. 1A or the hydraulic lock and a hydraulic release type of FIG. 4A.
The pressure fluid used for the lock or the release may be a gas such as compressed air instead of the illustrated pressure oil. Further, the pressure fluid for cleaning may be a gas or a liquid such as nitrogen in place of the illustrated compressed air.
[0033]
The positioning device of the present invention may be provided with a seating confirmation unit. For example, a detection nozzle hole (not shown) is opened in the support surface 2a on the upper surface of the flange 9a, and compressed air for detection is supplied to the detection nozzle hole. Then, when the supported surface 3a of the work pallet 3 comes into contact with the support surface 2a, the pressure in the detection nozzle hole increases. By detecting the pressure increase with a pressure switch or the like, it can be confirmed that the work pallet 3 is seated on the base plate 2.
[0034]
The combination of the reference block and the movable block is not a combination of the illustrated base plate 2 and the work pallet 3 but a combination of a machine tool table and a work pallet, a combination of a work pallet and a jig base, a jig base and a work. It may be a combination of pieces, a combination of a work jig such as a welding jig and a work such as a work piece. Further, the present invention is also applicable to positioning of workpieces and tools of various processing machines such as a laser beam machine and an electric discharge machine.
Note that the positioning device of the present invention can be used with only one set instead of using a plurality of sets.
[Brief description of the drawings]
FIG. 1A is a cross-sectional view of an automatic positioning device according to a first embodiment of the present invention, as viewed from an elevation. FIG. 1B is a plan view of the positioning device.
FIG. 2 is an enlarged cross-sectional view of a pressing tool provided in the positioning device.
FIG. 3 is a view similar to FIG. 2 showing a modification of the above-described pressing tool.
FIG. 4A and FIG. 4B show a second embodiment of the present invention. 4A is a view similar to FIG. 1A, and FIG. 4B is a view similar to FIG.
[Explanation of symbols]
2 ... Reference block (base plate), 3 ... Movable block (work pallet), 5 ... Positioning hole, 12 ... Center pillar, 13 ... Wedge surface, 15 ... Circular plug, 15a ... Peripheral wall, 15b ... Ceiling wall, 17 ... Pressing tool , 18: return means, 19: inclined groove, 21: output member, 31: lock means, 32: release means, 40: supply port, 41: discharge port.

Claims (7)

An annular center column (12) is protruded from the fixed side reference block (2) in the distal direction, and the center column (12) is fixed to the reference block (2).
A wedge surface (13) is provided on the outer periphery of the above-mentioned center column (12), which approaches the axis as it goes toward the above-mentioned tip,
An annular plug (15) inserted into the positioning hole (5) of the movable block (3) is arranged outside the above-mentioned center column (12),
A plurality of pressing tools (17) are supported on the peripheral wall (15a) of the annular plug (15) so as to be movable in the radial direction at intervals in the circumferential direction. 13) wedge-engaged with each other, and each of the pressing members (17) can be returned inward in the radial direction by a return means (18).
An output member (21) is movably inserted in the center axis (12) in the axial direction, and a distal end of the output member (21) is connected to the annular plug (15).
Locking means (31) and release means (32) are provided in the reference block (2), and the locking means (31) is connected to the annular plug (15) via the output member (21). An automatic positioning device characterized in that it is locked in the end direction and the release means (32) releases the annular plug (15) in the distal direction via the output member (21). The automatic positioning device according to claim 1,
The inner space of the peripheral wall (15a) of the annular plug (15) is covered with a ceiling wall (15b) in a hermetic manner, and the base of the peripheral wall (15a) is axially mounted on the center pillar (12). An automatic positioning device characterized in that it is movable and supported in a sealed manner. The automatic positioning device according to claim 1 or 2,
An automatic positioning device, wherein a plurality of the wedge surfaces (13) are provided on the center column (12) at intervals in a circumferential direction. The automatic positioning device according to claim 3,
A plurality of inclined grooves (19) are provided in the center pillar (12) at intervals in the circumferential direction, and the wedge surface (13) is formed on a bottom wall of the inclined groove (19). Automatic positioning device. The automatic positioning device according to claim 4,
An automatic positioning device, wherein the return means (18) is constituted by a fitting structure between the peripheral wall of the inclined groove (19) and the pressing tool (17). The automatic positioning device according to claim 1 or 2,
An automatic positioning device, wherein the wedge surface (13) is constituted by a tapered outer peripheral surface. The automatic positioning device according to any one of claims 1 to 6,
A cleaning fluid supply port (40) is provided in the reference block (2), and the cleaning fluid is supplied by a clearance between the peripheral wall (15a) of the annular plug (15) and the pressing tool (17). An automatic positioning device comprising: a discharge port (41); and the discharge port (41) communicates with the supply port (40).

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