JPS6130858B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing an indexing board, and more specifically, the present invention relates to a method for manufacturing an indexing board, and more particularly, two or more reference plates having a plurality of reference holes spaced at equal intervals on the same circumference, and a method that is harder than the reference plates and has reference holes. The present invention relates to a method for manufacturing an indexing board made of a combination of a plurality of steel balls slightly larger than the above. Conventionally, for indexing machines that divide the circumference into equal parts, the indexing reference plate is usually manufactured by machining, and therefore the indexing accuracy is determined by the machining accuracy. Therefore, there is the difficult problem of increasing the processing accuracy in order to create a higher-precision indexing machine, and the disadvantage of indexing machines is that their indexing accuracy gradually deteriorates as they are used. . Figures 5 and 6 show the conventionally used 6
This is an example of an equally divided index board.
As shown in Fig. 5, this is a reference plate 1 made by machining six reference holes 2 at equal intervals on the same circumference.
As shown in FIG. 6, the reference plate 1 is assembled to the fixed plate 4 by rotatably fitting the shaft portion 1a provided at the center of the reference plate 1 into the center hole 4a provided at the center of the fixed plate 4. , a hole 4b provided on the circumference of the fixed plate 4
By inserting a pin 5 into the reference hole 2 of the reference plate 1, the relative rotation of both plates 1 and 4 is fixed and indexing is performed. Of course, incorrect machining of the six reference holes 2 will result in incorrect placement of the index, and in addition, the clearance between the shaft portion 1a and the center hole 4a, the pin 5, the reference hole 2, and the hole 4b of the fixing plate 4. The clearance between the two causes an indexing error. Further, in the above-mentioned indexing machine, wear and deformation of each fitting part and sliding part that occur as the indexing machine is used further deteriorates its indexing accuracy. The present invention has been made in view of the above-mentioned conventional problems, and it is an object of the present invention to provide a manufacturing method that allows an indexing machine with higher accuracy than conventional indexing machines to be obtained by performing simple operations. This is the purpose. DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the indexing board manufacturing method of the present invention will be described in detail below with reference to FIGS. 1 to 3. The indexing board that is the subject of this manufacturing method has the required number of indexers or an integral multiple thereof (for example, 6, 12, 18, etc. in the case of 6 equal divisions) on the same circumference. Reference hole 2
It is composed of a combination of two or more reference plates 1 having 1 and a plurality of steel balls 3 interposed between two reference plates 1.
It is used in combination with a number of reference plates 1 and a number of steel balls 3 corresponding to the number of reference holes. The reference plate 1 has a reference hole 2 formed by machining similar to the conventional one, and therefore, the machining error of the reference hole 2 is the same as that of the conventional one. Further, a steel ball 3 that is harder than the reference plate 1 and whose outer diameter is larger than the inner diameter of the reference hole 2 is prepared. It is desirable that the steel ball 3 has a variation in outer diameter of 1 μm or less, and a steel ball 3 having this level of accuracy is easily obtained. Next, an example in which a set of indexing boards is made using two reference plates 1 and 1' will be explained with reference to the drawings. First, one reference plate 1 is appropriately set on the table of a pressurizing device (not shown), and then steel balls 3 are fitted and placed in each reference hole 2, respectively. Subsequently, the other reference plate 1' is placed so that each reference hole 2' of the other reference plate 1' fits with each steel ball 3 in an overlapping manner.
In this case, if there is a machining error in the reference holes 2 and 2' of both reference plates 1 and 1', as shown in FIG. Since the centers do not coincide, each steel ball 3 makes almost full contact with the peripheral edge of the lower reference hole 2, but partially contacts the peripheral edge of the upper reference hole 2'. .
In such a state, when the upper reference plate 1' is pressurized from above with an appropriate load, the contact portion 2a of the lower reference hole 2 with respect to each steel ball 3 and the upper reference hole 2' are caused by this pressurization. Contact part 2
a' will be plastically deformed by the steel balls 3, respectively. Hereinafter, the above pressure operation is performed while changing the position of the upper reference plate 1' relative to the lower reference plate 1 by the arrangement pitch of the reference holes 2', that is, the reference holes 2 of the upper reference plate 1' relative to the steel balls 3. The pressurizing operation is carried out once for all the holes while changing the combination of holes 2', and since there are six reference holes 2' in this embodiment, the pressurizing operation is repeated a total of six times in one turn. In this way, after performing the first run-in correction operation for both the reference plates 1, 1' and the steel ball 3, turn both the reference plates 1, 1' upside down, and then While changing the combination of the reference holes 2 of the reference plate 1,
A second run-in operation is performed by performing a total of six pressurization operations in the same manner as above. After that, by repeating the above fitting correction operation 3, 4 times...n times while changing the pressure load as appropriate or keeping it constant, the center position of the steel ball 3 will be adjusted to both sides as shown in Fig. 3. It comes to converge on the equally divided circumference of a perfect circle on the reference plates 1 and 1'. As a result, the indexing machining error of the reference holes 2, 2' of the reference plates 1, 1' is corrected, and the center position of the steel ball 3 relative to the reference plate is indexed, and in the end, the indexing process as an indexing plate is corrected. Output accuracy is improved. When the indexing board thus obtained is used, one of the reference plates 1 or 1' is used as the conventional fixed plate 4 shown in FIG. 6. In addition, when making multiple sets of indexing boards using three or more reference plates, in addition to the run-in operation described above for two boards, the run-in correction for all the reference plates is also performed by changing the combination of reference plates. The operation is repeated, thereby making it possible to obtain a plurality of sets of indexing discs that are compatible and have almost the same high indexing accuracy. Next, the table below shows the results of an experiment in which a pressurizing operation, that is, a fitting correction operation was performed according to the operating procedure of the above embodiment.

【table】

【table】

[Table] (Table 1) is an example of an experiment using three reference plates A, B, and C as a set.
It shows data about the board, and the operating procedure is as follows. 1st time (1st turn) Add 7t with reference plate A down and reference plate B up 2nd time Add 7t with reference plate B down and reference plate C up 3rd time Add 7t with reference plate C down and reference plate Place A on top and add 12t 4th time Put reference plate A down, put reference plate B on top and add 12t 5th time Place reference plate B on the bottom, put reference plate C on top and add 15t 6th time Put reference plate C down , 15t was added with reference plate A facing upward. Table 2 also shows an experimental example using three reference plates D, E, and F as a set, and the operating procedure is as follows. 1st time (1st turn) Add 5t with reference plate D at the bottom and reference plate E at the top 2nd time Add 5t with reference plate E at the bottom and reference plate F at the top 3rd time Add 5t with reference plate F at the bottom and reference plate Add 10t with D on top 4th time Add 10t with reference plate D on the bottom and reference plate E on top 5th time Add 13t with reference plate E on the bottom and reference plate F on top 6th time Add reference plate F Below, add 13t with reference plate D on top 7th time Add 15t with reference plate D on the bottom and reference plate E on top 8th time Add 15t with reference plate E on the bottom and reference plate F on top Further ( Table 3) is an example of an experiment in which a re-familiarization correction operation was performed on two of the three reference plates A and B for which the experiment in Table 1 was completed, and the operating procedure was as follows. It is. 1st time (1st turn) Add 16t with reference plate A down and reference plate B up 2nd time Add 16t with reference plate A and B upside down 3rd and 4th time add 17t as described above The same amount of 175t is added for the 5th and 6th additions. However, in each table, D ₁ to _{D 6} are the distances between the centers of the steel balls (unit:
mm) _. It is a value. As is clear from the above experimental results, the variation in the increase in error after the run-in correction is gradually reduced in proportion to the increase in the number of pressurization operations compared to before the correction, and finally, as shown in Fig. 5 and It is possible to obtain an indexing board with higher precision than the conventional one shown in FIG. 6 (σ _{o -1} is about 0.02). This is the third
Standard deviation σ _o ― ₁ is 0.017 by adjusting the fit up to the table.
This can be easily inferred from the fact that it is 0.024. As described in detail above, the present invention includes two or more reference plates having a plurality of reference holes equally spaced on the same circumference, and a plurality of steel balls that are harder than the reference plates and larger than the reference holes. When manufacturing an indexing machine consisting of a combination of It is possible to obtain a starting board. As the indexing board obtained in this way is used, the contact points with the steel balls of the reference plate,
In other words, even if the contact surface is worn or deformed, this wear or deformation does not cause a decrease in indexing accuracy, but rather has the advantage of improving and improving indexing accuracy as an extension of the run-in correction operation. .

[Brief explanation of the drawing]

Fig. 1 is a plan view showing one reference plate in the indexing board, Fig. 2 is a sectional view showing the state of the indexing board, which is made up of a combination of two reference plates and a steel ball, before pressurizing operation; Figure 3 is a sectional view showing the state after the pressurizing operation, Figure 4 is an explanatory diagram of the distance between the centers of steel balls on the reference plate, and Figures 5 and 6 are explanatory diagrams showing a conventional indexing board. . 1, 1'...Reference plate, 2, 2'...Reference hole, 3...
…wrecking ball.

Claims (1)

[Claims] 1. A split plate made of a combination of two reference plates in which a plurality of reference holes are formed at equal intervals on the same circumference, and a plurality of steel plates that are harder than the reference plates and larger than the reference holes. In the method of manufacturing the release plate, a steel ball is fitted and placed in each reference hole of one reference plate set in a predetermined position, and then the steel balls are fitted to the reference holes of another reference plate. At the same time, in this state, the upper reference plate is pressed against the lower reference plate with a predetermined load, and this pressurizing operation is then applied to the assembly of the reference holes of the upper reference plate against the steel balls. An operation step of performing at least one run-in correction operation by changing the alignment and performing the run-in correction operation on all the holes, and an operation step of performing the same run-in correction operation as above after turning both of the above reference plates upside down. A method of manufacturing an indexing board including. 2. Production of an indexing board consisting of a combination of three or more reference plates with a plurality of reference holes formed at equal intervals on the same circumference and a plurality of steel balls that are harder than the reference plates and larger than the reference holes. In this method, a steel ball is fitted and placed in each reference hole of one reference plate set at a predetermined position, and then the other reference plate is superimposed and placed so that the reference hole fits with the steel ball. At the same time,
In this state, the upper reference plate is pressed against the lower reference plate with a predetermined load, and then this pressurizing operation is performed for all holes by changing the combination of the reference holes of the upper reference plate with respect to the steel balls. By doing so, there is an operation step of performing at least one adjustment of the reference hole, an operation step of turning both of the reference plates upside down and then performing the same adjustment of adjustment as above, and further, a step of performing the adjustment of the adjustment of the reference hole at least once. A method for manufacturing an indexing board, which includes an operation step of changing the combination of plates and repeating the above-mentioned fitting correction operation for all reference plates.