JPS6125970Y2 - - Google Patents

Description

[Detailed description of the invention] This invention solves the problem that when grinding a workpiece while supporting it at both centers of a numerically controlled cylindrical grinder, the processing position relative to the grinding wheel will be displaced due to the difference in the center hole dimensions of the workpiece. The present invention relates to an automatic correction device.

Generally, in a cylindrical grinding machine, a table is placed on a bed so as to be movable in the longitudinal direction, and a headstock and a tailstock are mounted on this table. The spindle is supported within the headstock so as to be further movable in the longitudinal direction. When a workpiece is supported between both centers attached to the main spindle and tailstock, even if the workpieces have the same shape, the center hole dimensions of the workpieces vary, so the grinding side of the grinding wheel The side position of the workpiece machining changes. That is, as shown in Figure 1 A and B, if the center hole diameter of the workpiece 1 in A is φd ₁ and the center hole diameter in B is φd ₂ , then the difference in center hole depth δ ₀ is δ ₀ = 1/2 (d ₁ - d ₂ )・cot1/2θ where θ is the angle of the center hole, and the workpiece 1 will be installed at a position displaced from the grinding wheel 2 by this difference δ ₀ . In order to eliminate this displacement, first set the position of the workpiece locator 4 mounted on the table 3 at δ ₀ on the table.
₁ to the right as shown in FIG. In order to perform this corrective movement, conventionally a mechanical stopper has been attached to the bed to roughly position the table. However, this conventional method had the disadvantage that the operator had to set the position each time the workpiece was changed.

In order to solve the above-mentioned drawbacks, this invention automatically adjusts the position of the workpiece reference surface relative to the grinding surface of the grinding wheel for various workpieces by inputting the center hole dimensions of the workpiece in a numerically controlled cylindrical grinding machine. This is corrected to keep it constant.

Embodiments of this invention will be described below based on the drawings. It is assumed that program values A, B, C, . . . indicating the grinding position of the workpiece 1 are given as dimensions from the left end surface Z of the workpiece 1. When the workpiece 1 is supported at the center, the center hole diameter is φd.
Accordingly, the end surface Z is supported with a shift to the left from the center tip by δ=1/2 d·cot1/2θ. This value δ is because θ is generally constant at 60°, so δ=
It becomes 0.866d. Therefore, the table position program values indicating each grinding position of the workpiece 1 are A-δ, B-
δ, C−δ... Therefore, the center hole diameter dimension φdr of each workpiece is input into the keyboard switch 6 of the numerical control device, and the value d is temporarily stored in the storage device 7. When the input set is completed, the multiplier 8 calculates δ=
0.866d is calculated and stored in the program storage device 9 as the center hole depth. On the other hand, program values A, B, and C indicating the grinding position are input to the input device 10 and stored in the program storage device 9. Next, the arithmetic unit 11 calculates the difference between the program values A, B, C, etc. indicating each grinding position, and calculates A-δ, B-δ, C.
-δ... is calculated. Based on the result of this calculation device 11, a command is given to the positioning device 12 and the table 3 is
This allows for positioning. In addition, in this attitude, the dimensions from the workpiece end face to the grinding surface are constant,
In addition, although we have explained the case where the grinding diameter is the same, in particular, in the angle slide grinder that the applicant has proposed earlier, the position of the grinding wheel end side surface on the spindle side (determined by the shape of the grinding wheel) when the processing diameter is φ ₀ is An automatic end face sizing device is installed on the bed facing the grinding wheel at a certain distance from the fixed point above), and the program of the numerical control device is set from the machine origin to the above fixed point.
The effect increases synergistically when used in combination with a positioning method in which the amount of deviation from a fixed point to the zero point position of the end face automatic sizing device above the bed is set as an offset value that is not affected by the workpiece. It goes without saying that this method can also be applied to cases where the dimensions between the end face of the workpiece and the grinding surface and the grinding diameter are different.

As detailed above, there is no need for the operator to change the setup due to the difference in center hole dimensions every time the workpiece changes, and the difference in center hole dimensions can be automatically changed by simply inputting the center hole dimensions in advance or each time. This has the practical effect of improving operability by correcting errors in the installation position of the workpiece in the longitudinal direction.

[Brief explanation of the drawing]

Figure 1 A and B are diagrams showing the displacement of the workpiece reference and machining position due to the center hole dimension difference, Figure 2 is a diagram explaining the workpiece machining program values, and Figure 3 is a diagram showing the center hole dimensions input. This is a block diagram for performing table position correction. 3...table, 6...keyboard switch,
7... Storage device, 8... Multiplier, 9... Program storage device, 10... Input device, 11... Arithmetic device, 12... Positioning device.

Claims (1)

[Scope of Claim for Utility Model Registration] A numerically controlled cylindrical grinder capable of longitudinally positioning a table according to commands from a numerical controller, comprising: means for inputting a center hole diameter dimension; a means for inputting a program value indicating a grinding position; A means for storing center hole diameter dimensions; a multiplication means for converting the input center hole diameter dimension into a center hole depth; a means for storing the converted center hole depth and the program value; and a grinding position of the workpiece. and a positioning means that receives the output of the calculation means and causes the table to perform corrective positioning. A table position correction device for a numerically controlled cylindrical grinder, which is characterized by correcting displacement of the workpiece processing position due to differences in hole diameter dimensions.