JP2014081380A - Positioning mechanism and positioning method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positioning mechanism which is easily attachable/detachable and which can reproduce positional relationship with good accuracy, and a positioning method.SOLUTION: A positioning mechanism is for performing positioning between a cylinder block 5 having positioning holes 5b and a measurement jig plate 2 having guide holes 2b corresponding to the positioning holes 5b. The positioning mechanism includes: a first pin 3 which includes a fixing part which is fixed to the positioning hole 5b on one side and an adjustment part which is inserted into the guide hole 2b on the other side, in which a female screw part is formed inside the fixing part, in which a taper part is formed and also a split groove is formed so as to expand in a radial direction inside the adjustment part; and a second pin 4 in which a pressing part, which pushes and expands the adjustment part in the radial direction by coming into contact with a male screw part which is screwed into the female screw part and the taper part, is formed.

Description

  The present invention relates to a positioning mechanism and a positioning method for an object to be measured and a measuring jig plate, particularly in positioning of two members.

  In a portable inner diameter roundness and cylindricity measuring machine, for example, a bore of a cylinder block of an engine which is a cylindrical hole is a measurement target. In the measurement, the measuring machine is positioned at the top of the bore. However, recent cylinder blocks use aluminum-based materials, and the materials are soft. For this reason, the cylinder block may be damaged due to contact or friction when the measuring machine is installed. In order to cope with this problem, a measurement jig plate is attached between the cylinder block and the measuring machine during measurement. Since the measuring machine performs positioning using the measurement holes provided in the measurement jig plate, the measurement jig plate is attached to the cylinder block with the center of the bore and the measurement hole aligned.

  Conventionally, in the two members that perform such attachment and removal, various positioning mechanisms have been devised so that one of the removed members can be attached again in the same positional relationship. For example, as shown in FIG. 10A, a method of positioning by inserting one or more parallel pins 10 into a guide hole 12 provided in the plate 11 has been devised. In such a positioning mechanism, a parallel pin 10 having a diameter smaller than that of the guide hole 12 is used because the parallel pin 10 is inserted into and removed from the guide hole 12 as shown in FIG. For this reason, it is possible to move by the gap between the parallel pin 10 and the guide hole 12, and high-precision positioning cannot be performed.

  On the other hand, as shown in FIGS. 11A and 11B, accuracy is improved by reducing the gap between the guide hole 12 using one parallel pin 10 and one or more diamond pins 13. A positioning mechanism has been devised. Further, as shown in FIGS. 12A and 12B, there is a positioning mechanism that enables high-precision positioning by fitting one or more taper pins 14 into a taper hole 16 provided in the plate 15. It has been devised. (For example, refer to Patent Document 1).

JP-A-10-175133

  However, in such a positioning mechanism, since it is necessary to process the tapered hole 16 with high accuracy at the same time, it takes time and effort to increase the part price. Further, since the pin is pushed into the hole, a strong force is required for attachment and removal, and attachment and removal are not easy.

  The present invention has been made for such a problem, and an object of the present invention is to provide a positioning mechanism and a positioning method that can be easily attached and detached and can accurately reproduce the positional relationship.

  In order to achieve the above object, a positioning mechanism according to one aspect of the present invention is a positioning mechanism for positioning a measured object having a positioning hole and a measuring jig having a guide hole corresponding to the positioning hole. A fixing portion that is fixed to the positioning hole on one side, an adjustment portion that is inserted into the guide hole on the other side, a female screw portion is formed inside the fixing portion, and an inner side of the adjustment portion Has a taper part and a first pin with a split groove formed to expand in the radial direction, a male screw part screwed into the female screw part, and the taper part to contact the adjustment part in the radial direction. And a second pin formed with a pressing portion to be widened.

  A positioning method according to another aspect of the present invention is a positioning method for positioning a measured object having a positioning hole and a measuring jig having a guide hole corresponding to the positioning hole, A fixing part fixed to the positioning hole on the side, an adjustment part inserted into the guide hole on the other side, a female screw part formed inside the fixing part, and a taper part inside the adjustment part A step of fixing a fixing portion of the first pin, which is formed and formed with a split groove so as to expand in the radial direction, a step of inserting the adjustment portion of the first pin into the guide hole, a female The male screw portion of the second pin formed with the male screw portion screwed into the screw portion and the pressing portion that contacts the taper portion and expands the adjustment portion in the radial direction is used as the female screw portion of the first pin. By screwing, the pressing part contacts the taper part. And a step of pushing the adjuster in a radial direction with.

  According to the present invention, the fixing portion of the first pin is fixed to the positioning hole of the object to be measured, the adjusting portion of the first pin is inserted into the guide hole of the measuring jig, and the male screw portion of the second pin Is inserted into the female threaded portion of the first pin, thereby positioning the object to be measured and the measuring jig. Accordingly, the measurement jig can be easily attached to and detached from the measurement object, and the positional relationship between the measurement object and the measurement jig can be accurately reproduced.

The perspective view which showed the structure of the positioning mechanism based on this invention Diagram showing the shape of the measurement jig plate The figure which showed the shape of the 1st pin The top view which showed another example of the shape of the dividing groove of the 1st pin The top view which showed another example of the shape of the dividing groove of the 1st pin The figure which showed the shape of the 2nd pin Top view showing the difference in the direction of position adjustment according to the direction of the split groove Side sectional view showing the state of measuring the inside of the cylinder block bore with a measuring machine Plan view showing the operating state of the fixed claw Diagram showing an example of a conventional positioning mechanism A diagram showing another example of a conventional positioning mechanism The figure which showed another example of the conventional positioning mechanism

  Hereinafter, preferred embodiments of a positioning mechanism and a positioning method according to the present invention will be described in detail with reference to the accompanying drawings.

  1 is a perspective view showing the configuration of the positioning mechanism, FIG. 2 is a diagram showing the shape of the measurement jig plate, FIG. 3 is a diagram showing the shape of the first pin, and FIG. 4 is a diagram showing the allocation of the first pin. FIG. 5 is a top view showing another shape example of the groove, FIG. 5 is a top view showing still another shape example of the split groove of the first pin, and FIG. 6 is a view showing the shape of the second pin.

  The positioning mechanism 1 includes a measurement jig plate 2, first pins 3 and 3, and second pins 4 and 4.

  The measuring jig plate 2 is placed on the cylinder block 5 when measuring a bore 5a, which is a cylindrical hole formed in the cylinder block 5 of the engine, using a portable inner diameter roundness and cylindricity measuring machine. Is done. A plurality of positioning holes 5b are formed on the cylinder block 5 with a certain distance from the bore 5a. As shown in FIG. 2A, the measurement jig plate 2 has a measurement hole 2a and a guide hole 2b formed in the same positional relationship as the bore 5a and the positioning hole 5b. Each guide hole 2b is provided with a screw hole 2c for attaching a retaining screw as shown in FIG. 2 (b).

  The first pin 3 is formed in a cylindrical shape as shown in FIG. 3A or 3B, and is fixed to one side by being screwed into the positioning hole 5b of the cylinder block 5 or driven in. 3a and an adjustment portion 3b to be inserted into the guide hole 2b of the measurement jig plate 2 is provided on the other side. A female screw portion 3a1 is formed inside the fixed portion 3a. The adjusting portion 3b is formed with a tapered portion 3b1 on the inside and four split grooves 3c in a cross shape so as to expand in the radial direction. A retaining groove 3d is formed on the side surface of the adjusting portion 3b. The retaining groove 3d is pressed against the retaining screw that prevents the first pin 3 from rotating when the male screw is inserted into the female thread portion 3a1.

  The number of the split grooves 3c may be three at an equal angle in a radial manner as shown in FIG. 4, or two in a straight shape as shown in FIG. 5, and four or more may be formed radially. Also good. The second pin 4 includes a male screw portion 4a attached to the female screw portion 3a1 of the first pin 3 as shown in FIG. 6, and pushes the adjustment portion 3b in a radial direction by contacting the taper portion 3b1. A contact portion 4b is formed.

  Next, the positioning method according to the present invention will be described in detail.

  In the positioning method, first, the fixing portion 3a of the first pin 3 is fixed to the plurality of positioning holes 5b of the cylinder block 5 shown in FIG. 1 by screwing, driving or the like. In this embodiment, it is fixed to the two positioning holes 5b formed in the upper left part and the lower right part of FIG. 1, but the present invention is not limited to this, and the first pin 3 is attached to more positioning holes 5b. It may be fixed.

  Subsequently, the adjustment portion 3 b of the first pin 3 fixed to the positioning hole 5 b is inserted into the guide hole 2 b of the measurement jig plate 2, and the measurement jig plate 2 is placed on the cylinder block 5. After the measurement jig plate 2 is placed, a retaining screw is inserted from the screw hole 2c and pressed against the retaining groove 3d of the first pin 3, so that the first pin 3 cannot be rotated.

  Subsequently, the male screw portion 4 a of the second pin 4 is screwed into the female screw portion 3 a 1 of the first pin 3. When the second pin 4 is screwed into the first pin 3, the pressing portion 4 b comes into contact with the tapered portion 3 b 1 of the first pin 3. Further, by screwing the second pin 4 into the first pin 3, the adjustment portion 3b is pushed and expanded in the radial direction.

  As a result, there is no gap between the guide hole 2b and the adjusting portion 3b of the first pin 3, the measurement jig plate 2 is fixed, and the center positions of the positioning hole 5b and the guide hole 2b are aligned. It is done. Similarly, the measuring jig plate 2 is fixed and positioned without a gap between the adjusting portion 3b in the two or more guide holes 2b.

  By aligning the center positions of the plurality of positioning holes 5b and the guide holes 2b, the center position of the bore 5a formed with a certain distance from the positioning hole 5b is in the same positional relationship as the positioning hole 5b and the bore 5a. It is positioned with high accuracy with the center position of the measurement hole 2a formed with respect to the guide hole 2b.

  In the present invention, when the first pin 3 in which the two split grooves 3c are linearly formed as shown in FIG. 5 is used, the positioning position can be adjusted depending on the direction of the split groove 3c. Become. Specifically, the adjustment portion 3b of the first pin 3 extends in the X direction by orienting the split groove 3c of the upper left first pin 3 shown in FIG. , The positioning position is adjusted in the X direction. Similarly, when the split groove 3c of the first pin 3 at the lower right shown in FIG. 7 is oriented perpendicularly to the arrow Y direction, the adjusting portion 3b of the first pin 3 extends in the Y direction, and the Y direction at the lower right. The positioning position is adjusted.

  Each adjustment amount in the X and Y directions. The second pin 4 is screwed into the first pin 3 and adjusted by the amount by which the first pin 3 is expanded. As a result, the measuring jig plate 2 is fixed and the position is finely adjusted by the screwing amount.

  After the positioning of the measurement jig plate 2 is completed, the measuring machine 6 is installed on the measurement hole 2a on the bore 5a where the measurement is performed as shown in FIG. The measuring machine 6 is provided with three fixing claws 7 on the installation fixing part 6a. As shown in FIG. 9 (a), the fixing claw 7 rotates about a pin 7c as a rotation center by rotating a plate (not shown) to which the guide pin 7a is attached and moving the guide pin 7a between the guide grooves 7b. To do. Thereby, the fixed claw 7 is pressed against the side surface of the measurement hole 2a as shown in FIG. 9B. The pressed fixing claw 7 fixes the measuring device 6 to the measuring jig plate 2 and aligns the shaft 6b of the measuring device 6 with the center of the measuring hole 2a.

  After the measurement by the measuring device 6, the second pin 4 is removed from the first pin 3, so that the expanded adjustment portion 3 b is restored and the measurement jig plate 2 is easily removed from the cylinder block 5. Things will be possible. After the removal, the adjusting portion 3b is inserted into the guide hole 2b of the measuring jig plate 2 and the second pin 4 is screwed into the first pin 3 so that the bore 5a and the measuring hole 2a are in the same positional relationship each time. Positioning is performed.

  As described above, according to the positioning mechanism and the positioning method according to the present invention, the center positions of the positioning hole 5b and the guide hole 2b are adjusted by the plurality of first pins 3 and the second pins 4, The center positions of the bore 5a and the measurement hole 2a are positioned with high accuracy. In addition, the measuring jig plate 2 can be easily removed simply by removing the second pin 4, and positioning can be performed by screwing the second pin 4 into the first pin 3 again. Thus, the positional relationship can be accurately reproduced.

  DESCRIPTION OF SYMBOLS 1 ... Positioning mechanism, 2 ... Measuring jig plate, 2a ... Measurement hole, 2b ... Guide hole, 2c ... Screw hole, 3 ... First pin, 3a ... Fixing part, 3a1 ... Female screw part, 3b ... Adjustment part 3b1... Tapered portion, 3c. Split groove, 3d... Retaining groove, 4. ... measuring machine, 6a ... installation fixing part, 7 ... fixing claw, 7a ... guide pin, 7b ... guide groove, 7c ... pin, 10 ... parallel pin, 11, 15 ... plate, 12 ... guide hole, 13 ... diamond pin, 14 ... Taper pin, 16 ... Taper hole

Claims (2)

A positioning mechanism for positioning an object to be measured having a positioning hole and a measuring jig having a guide hole corresponding to the positioning hole,
A fixing part fixed to the positioning hole is provided on one side, an adjustment part inserted into the guide hole is provided on the other side, and a female screw part is formed inside the fixing part. A first pin having a taper portion formed inside and a split groove formed to expand in the radial direction;
A second pin formed with a male screw part screwed into the female screw part and a pressing part that contacts the taper part and expands the adjustment part in the radial direction;
A positioning mechanism comprising: A positioning method for positioning a measured object having a positioning hole and a measuring jig having a guide hole corresponding to the positioning hole,
A fixing part fixed to the positioning hole is provided on one side, an adjustment part inserted into the guide hole is provided on the other side, and a female screw part is formed inside the fixing part. A step of fixing the fixing portion of the first pin in which the tapered portion is formed on the inner side and the split groove is formed so as to expand in the radial direction in the positioning hole;
Inserting the adjustment portion of the first pin into the guide hole;
The male screw portion of the second pin formed with a male screw portion to be screwed into the female screw portion and a pressing portion that is in contact with the taper portion and expands the adjustment portion in the radial direction is formed on the first pin. By screwing into the female threaded portion of the pin, the pressing portion contacts the tapered portion and pushes the adjusting portion in a radial direction; and
A positioning method comprising:

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