JP2013043258A - Workpiece positioning tool for machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positioning tool capable of handling workpieces in various shapes.SOLUTION: A positioning tool for the alignment of a workpiece placed on a table of a machine tool includes a body having a through-hole in which a fixing bolt fixed to a tool fixing hole formed at the table is inserted, an arm that protrudes outward radially from the body, an eccentric pin rotatably arranged to the arm, and a pin lock for regulating the rotation of the eccentric pin. The outer peripheral surface of the eccentric pin abuts on a side end face of the workpiece.

Description

  The present invention relates to a jig for positioning a workpiece placed on a table of a machine tool.

  When machining a workpiece automatically using a machine tool such as an NC milling machine or machining center, a positioning jig is used to position the workpiece so that the workpiece reference surface matches the machining reference position on the table on which the workpiece is placed. It is used. Normally, this positioning jig is provided with a cylindrical contact body, and the workpiece is positioned by pressing the reference surface of the workpiece against the contact body. In addition, when fixing a workpiece | work to a table, the clamp jig prepared separately is used.

  The table of the machine tool is provided with a plurality of jig fixing holes for fixing the positioning jig at regular intervals, and the jig fixing hole suitable for the position where the workpiece is brought into contact is selected and positioned. The tool can be fixed.

  When machining workpieces having the same shape continuously, the workpiece can be positioned efficiently by using such a positioning jig. As an example of the positioning jig, a positioning jig applicable to a plurality of types of workpieces having similar shapes has been proposed (see Patent Document 1).

JP-A-5-182891

  By the way, when a workpiece is machined by the machine tool, there are many types of workpieces to be machined, and the workpiece shapes are often complicated. Therefore, even if an attempt is made to install a positioning jig at an appropriate position on the table for each workpiece shape, there may be no jig fixing hole at that position. In this case, since a positioning jig cannot be used, the position must be manually adjusted using a dial gauge or the like, resulting in a problem that workability is extremely deteriorated.

  The present invention has been made in view of such a background, and an object of the present invention is to provide a positioning jig that can cope with various workpiece shapes by widening the position adjustment range of a contact body that contacts a workpiece. .

One aspect of the present invention is a positioning jig for positioning a workpiece placed on a table in a machine tool,
A main body having a through hole through which a fixing bolt for fixing to a jig fixing hole provided in the table is inserted;
An arm portion projecting radially outward from the main body portion;
An eccentric pin rotatably disposed on the arm portion;
A pin lock portion for restricting the rotation of the eccentric pin,
In the positioning jig, the outer peripheral surface of the eccentric pin is configured to come into contact with the side end surface of the workpiece.

  The positioning jig includes the main body portion, the arm portion, and the eccentric pin disposed on the arm portion. The main body part and the arm part can be fixed by freely rotating with the axis of the through hole provided in the main body part as a rotation axis. Therefore, the eccentric pin can be installed at an arbitrary position in a circle centered on the through hole and having the length of the arm portion as a radius.

  The eccentric pin is rotatably disposed on the arm portion. When the eccentric pin is rotated, the position of the outer peripheral surface of the eccentric pin changes. For this reason, fine adjustment of the position of the workpiece reference surface in contact with the outer peripheral surface can be easily performed.

  And the said positioning jig has the said pin lock part which controls rotation of the said eccentric pin. The position of the outer peripheral surface of the eccentric pin is fixed by the pin lock portion. Therefore, the reference surface position of the work contacting the outer peripheral surface can be kept constant.

  As described above, by providing both the arm part and the eccentric pin, the position adjustment of the eccentric pin by the rotation of the arm part and the fine adjustment by the rotation of the eccentric pin itself can be combined to support various workpiece shapes. Positioning the workpiece.

3 is a perspective view showing a positioning jig in Embodiment 1. FIG. FIG. 3 is an explanatory view showing a positioning jig in use according to the first embodiment. Sectional drawing of the positioning jig of the use condition in Example 1 (the AA arrow directional cross-sectional view of FIG. 1). FIG. 9 is an explanatory diagram illustrating a state where a workpiece is positioned in the second embodiment.

  The positioning jig is fixed to a jig fixing hole provided in a table of the machine tool using a fixing bolt inserted through the main body. The jig fixing hole is provided in the table in order to insert a fixing bolt and fix one end thereof. The shape of the jig fixing hole is an independent perfect circular or elongated hole or groove. There is a shape.

  Moreover, the eccentricity in the eccentric pin means that the distance from the rotation axis of the eccentric pin to the outer peripheral surface is not uniform. When the eccentric pin itself rotates, it comes into contact with the workpiece at a position different from that before the rotation on the outer peripheral surface. Therefore, before and after rotating the eccentric pin, the distance from the rotating shaft to the workpiece contact position on the outer peripheral surface changes. Therefore, the position of the reference plane of the workpiece can be changed by rotating the eccentric pin.

  In the positioning jig, it is preferable that the distance between the rotation center of the eccentric pin and the axis of the through hole is not less than ½ of the interval between the jig fixing holes. ). In this case, the eccentric pins can be arranged at all positions between adjacent jig fixing holes by adjusting the pivot position of the arm. Since the distance between the center of rotation of the eccentric pin and the axis of the through hole is too long, the upper limit of the distance is preferably about the same as the interval between adjacent jig fixing holes. There should be.

  Further, the outer shape of the eccentric pin can be circular (claim 3). In this case, when performing the fine adjustment of the workpiece position as described above, it becomes easy to continuously change the distance from the axis of the eccentric pin to the outer peripheral surface as the eccentric pin rotates.

  Further, the eccentric pin that has a pin shaft body inserted through the pin shaft hole provided in the arm portion and can slide and rotate the pin shaft body in the pin shaft hole can be used. Item 4). In this case, the eccentric pin can be disposed on the arm portion in a rotatable state and in a highly rigid state.

  Further, in the case of using the eccentric pin configured to be rotatable as described above, the pin lock portion communicates with the pin shaft hole from the side surface of the arm portion in order to more reliably restrict the rotation. A pin fixing screw hole provided so as to have a pin fixing screw meshing with the pin fixing screw hole, and a mechanism provided with a mechanism for compressing and fixing the shaft body of the eccentric pin by the pin fixing screw. (Claim 5).

  In this case, the rotation of the eccentric pin can be more reliably regulated by pressing and fixing the shaft body of the eccentric pin. If the eccentric pin is not sufficiently fixed, the eccentric pin rotates when the workpiece to be processed comes into contact with the outer peripheral surface of the eccentric pin, and the workpiece reference surface is shifted from the processing reference position. There is a risk of being.

In the case where the pin lock portion for compressing and fixing the pin shaft body as described above is used, the pin lock portion may have pin fixing screw holes and pin fixing screws arranged at least at two or more locations. Good (Claim 6).
In this case, the rotation of the pin shaft body can be more reliably regulated by fixing the pin shaft body with a plurality of pin fixing screws.

  In addition, when providing the said 2 or more pin fixing screw hole, the position is not specifically limited. That is, as viewed from the axial direction of the pin shaft hole into which the eccentric pin is inserted, the pin fixing screw hole may be provided so as to overlap or may be provided radially. When pin fixing screw holes are provided radially, even if pin fixing screw holes provided in one direction may not be used due to interference with the workpiece shape, pin fixing screw holes provided in another direction may cause It becomes possible to regulate the rotation of the eccentric pin.

Example 1
Examples of the positioning jig will be described with reference to FIGS.
The positioning jig 1 of this example is a positioning jig for positioning a workpiece 8 placed on a table 9 in a machine tool, and is a fixing bolt 91 that is fixed to a jig fixing hole 90 provided in the table 9. It has the main-body part 10 provided with the through-hole 11 which penetrates. Further, as shown in FIG. 1, an arm portion 2 projecting radially outward from the main body portion 10, an eccentric pin 3 rotatably disposed on the arm portion 2, and rotation of the eccentric pin 3 And a pin lock portion 4 for regulating The outer peripheral surface 30 of the eccentric pin 3 is configured to contact the side end surface of the workpiece 8.
This will be described in detail below.

  As shown in FIGS. 1 and 3, the main body portion 10 of the positioning jig 1 is a cylindrical part having a through hole 11 provided so as to penetrate the central axis. The inner diameter of the through hole 11 is adjusted to a dimension that slides smoothly without large play corresponding to the outer diameter of the shaft body of the fixing bolt 91.

  An arm portion 2 is attached to the upper surface of the main body portion 10. As shown in FIGS. 1 and 2, the arm portion 2 has a shape that protrudes outward in the radial direction of the main body portion 10 from an arm base portion 22 having an arcuate outer shape having the same curvature as the main body portion 10. As shown in FIG. 3, the arm base portion 22 is fixed to the main body portion 10 with bolts 14 inserted from the lower surface of the main body portion 10.

  As shown in FIGS. 1 and 3, the arm base 22 is provided with a hole 21 having a diameter larger than the head of the fixing bolt 91 at a position coaxial with the through hole 11 of the main body 10. . The through hole 11 and the hole 21 having different diameters overlap each other so that the upper surface 100 of the main body 10 functions as a seating surface that receives the head of the fixing bolt 91. Further, a pin shaft hole 20 is provided at the distal end portion of the arm portion 2 protruding outward in the radial direction when viewed from the main body portion 10.

  As shown in FIG. 3, the pin shaft body 31 of the eccentric pin 3 is inserted into the pin shaft hole 20. The eccentric pin 3 has a disk shape, and is provided in an eccentric state at the upper end of the cylindrical pin shaft body 31, that is, so that the central axes of both are shifted. The eccentric pin 3 is provided with a fine adjustment hole 32 that meshes with a hexagon wrench at a position that is coaxial with the pin shaft body 31, and the pin shaft body 31 slides and rotates within the pin shaft hole 20, and together with the eccentric pin, 3 rotation is possible.

  As shown in FIGS. 1 and 2, the pin lock portion 4 that restricts the rotation of the eccentric pin 3 has four pin fixing screw holes provided on the side surface of the arm portion 2 so as to communicate with the pin shaft hole 20. (Not shown) and a pin fixing screw 41 that meshes with the pin fixing screw hole. The pin fixing screw holes are provided at two positions on each of the two side surfaces at the tip of the arm portion 2 so as to face each other with the central axis of the pin shaft hole 20 interposed therebetween.

  As shown in FIG. 3, the positioning jig 1 inserts the shaft portion of the fixing bolt 91 into the through hole 11 and the jig fixing hole 90, and connects the main body portion 10 and the table 9 to the head of the fixing bolt 91 and the fixing bolt. It can be fixed to the table 9 by tightening with a nut 92 that meshes with 91.

  Next, the function and effect of this example will be described. As shown in FIGS. 2 and 3, the positioning jig 1 has a fixing bolt 91 inserted through the through hole 11 of the main body portion 1 and the hole 21 of the arm portion 2, and the inner diameter of the through hole 11 is equal to the fixing bolt. The dimension is adjusted to smoothly slide in accordance with the outer diameter of the shaft body 91. Therefore, the main body portion 10 and the arm portion 2 can be fixed on the table 9 by freely rotating with the axis of the through hole 11 as a rotation axis. Therefore, the eccentric pin 3 disposed at the distal end of the arm portion 2 has an arbitrary distance on the circumference indicated by a broken line 33 in FIG. 2 having a radius from the axis of the through hole 11 to the pin shaft body 31. It becomes possible to install in the position.

  Further, the eccentric pin 3 provided in the arm portion 2 has a disk shape, and is disposed so as to be rotatable together with a pin shaft body 31 that slides and rotates in the pin shaft hole 20. Therefore, the rotation of the eccentric pin 3 can continuously change the distance from the center of rotation of the eccentric pin 3 to the point of contact with the workpiece on the outer peripheral surface 30. Therefore, the position of the reference plane of the workpiece can be finely adjusted by rotating the eccentric pin 3.

  The work reference surface can be finely adjusted within a range in which the outer peripheral surface 30 can be disposed by rotating the eccentric pin 3. In this example, when the eccentric pin 3 rotates, the position of the outer peripheral surface can be changed to the broken line 300 shown in FIG. Therefore, the reference surface of the workpiece 8 that is in contact with the outer peripheral surface can be shifted to the position of the broken line 80 at the maximum.

  In addition, the pin lock portion 4 is a pin fixing screw hole provided at two locations in each direction so as to sandwich the central axis of the pin shaft hole 20 at a portion protruding radially outward of the main body portion 10 of the arm portion 2. And a pin fixing screw 41. Therefore, the rotation of the pin shaft body 31 can be more reliably regulated by the plurality of pin fixing screws 41, and the reference surface position of the workpiece 8 contacting the outer peripheral surface 30 can be kept constant.

  Further, as viewed from the pin shaft hole 20, pin fixing screw holes are provided radially. Therefore, even if there is a pin fixing screw hole that cannot be used due to interference with the workpiece 8, the rotation of the eccentric pin 3 can be restricted by the pin fixing screw hole provided in another direction.

  Further, the pin shaft body 31 can be inserted into the pin shaft hole 20 and can be slid and rotated in the pin shaft hole 20. Therefore, the eccentric pin 3 can be arranged on the arm portion 2 in a rotatable state and in a highly rigid state.

(Example 2)
In this example, an example in which a workpiece is positioned using a plurality of the positioning jigs 1 described in the first embodiment will be described.

  As shown in FIG. 4, the workpiece 8 used in this example has a shape obtained by cutting off a part of a disk-shaped member. A case is assumed in which drilling of the six processing holes 84 shown in FIG. 4 is continuously performed on a plurality of workpieces using an NC milling machine.

  First, based on the shape and dimensions of the workpiece 8, a reference plane necessary for making the workpiece 8 coincide with the machining reference position is set. Specifically, the straight portions 81 and 82 of the workpiece 8 are provided on the reference surface for arranging in parallel to the jig fixing hole 90, and the arc portion is provided on the reference surface for determining the position in the direction perpendicular to the jig fixing hole 90. 83 are set.

  Next, in order to make the three reference surfaces coincide with the processing reference position, a point to be brought into contact with the outer peripheral surface 30 of the positioning jig 1 is determined for each reference surface. And the position which fixes the positioning jig 1 to the jig fixing hole 90 is calculated so that the outer peripheral surface 30 is arrange | positioned in the said point.

  According to the position calculated as described above, the three positioning jigs 1 (a) to 1 (c) are arranged on the table 9 before placing the work 8, and the fixing bolt 91 and the nut 92 are used to Fix in position. The interval between the jig fixing holes 90 provided in the table 9 of the NC milling machine is 80 mm, and the distance from the axis of the pin shaft body 31 of the positioning jig 1 to the axis of the through hole 11 in the main body 10. Is 40 mm.

  Then, the workpiece 8 is brought into contact with the positioning jig 1 arranged as described above as shown in FIG. At this time, only during the first machining, it is confirmed by the dial gauge that the three reference surfaces 81, 82, 83 coincide with the machining reference position of the NC milling machine. When the reference surface is deviated from the processing reference position, the eccentric pin 3 is rotated to finely adjust the position of the workpiece 8 so that the reference surface matches the processing reference position. After the workpiece 8 positioned in this way is fixed by a separately prepared clamping jig, drilling is performed.

  In this example, as shown in FIG. 4, the outer peripheral surface 30 of the eccentric pin 3 can be disposed at a position away from the jig fixing hole 90 of the table 9. That is, by using the positioning jig 1 having both the arm portion 2 and the eccentric pin 3, the position adjustment of the eccentric pin 3 by the rotation of the arm portion 2 and the fine adjustment by the rotation of the eccentric pin 3 itself are performed. The positioning can be performed in correspondence with the workpiece 8 having a complicated shape without depending on the position of the combination and jig fixing hole 90.

  Particularly in this example, the distance from the through hole 11 to the rotation center of the eccentric pin 3 is ½ of the interval between the jig fixing holes 90. Therefore, the eccentric pins 3 can be arranged at all positions between the adjacent jig fixing holes 90 by adjusting the rotation position of the arm portion 2.

  On the other hand, when trying to position the workpiece 8 using a conventional positioning jig having no arm portion, the positioning jig cannot be disposed at an appropriate position. For this reason, every time the workpiece 8 is placed on the table 9, positioning must be performed using a dial gauge or the like, and workability is greatly reduced as compared with the case where the positioning jig 1 is used.

DESCRIPTION OF SYMBOLS 1 Positioning jig 10 Body part 11 Through hole 2 Arm part 20 Pin shaft hole 3 Eccentric pin 30 Outer peripheral surface 4 Pin lock part 8 Work 9 Table 90 Jig fixing hole 91 Fixing bolt

Claims (6)

A positioning jig for positioning a workpiece placed on a table in a machine tool,
A main body having a through hole through which a fixing bolt for fixing to a jig fixing hole provided in the table is inserted;
An arm portion projecting radially outward from the main body portion;
An eccentric pin rotatably disposed on the arm portion;
A pin lock portion for restricting the rotation of the eccentric pin,
A positioning jig, wherein an outer peripheral surface of the eccentric pin is configured to abut on a side end surface of the workpiece.   2. The positioning jig according to claim 1, wherein the distance between the axis of the pin that is the center of rotation of the eccentric pin and the axis of the through hole is 1 / of the interval between the jig fixing holes in the table. A positioning jig having two or more.   The positioning jig according to claim 1 or 2, wherein an outer shape of the eccentric pin is circular.   The positioning jig according to any one of claims 1 to 3, wherein the eccentric pin includes a pin shaft body that is inserted and disposed in a pin shaft hole provided in the arm portion. A positioning jig characterized in that the eccentric pin is rotated by sliding and rotating a body in the pin shaft hole.   5. The positioning jig according to claim 4, wherein the pin lock portion includes a pin fixing screw hole provided so as to communicate with the pin shaft hole from a side surface of the arm portion, and a pin fixing that meshes with the pin fixing screw hole. A positioning jig comprising: a screw, and configured to compress and fix the shaft body of the eccentric pin with the pin fixing screw.   The positioning jig according to claim 5, wherein the pin lock portion has pin fixing screw holes and pin fixing screws arranged at least at two or more locations.

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