JPH04289072A - Control of dress for grindwheel - Google Patents

Abstract

PURPOSE:To reduce a dress grinding time, and improve a machine operation ratio by setting an aerial line, and performing dressing at a predetermined dress grinding speed on the grindwheel side where the track of dress moulding exceeds the aerial line. CONSTITUTION:A dressor 5 is at a point A, it advances at a rapid traverse speed to a point B toward an aerial line P, and it further advances to a point C equivalent to an outer circumferential line of a grindwheel at a normal dress grinding speed. It advances at the dress grinding speed from the point C in the direction of X to a point D to grind the outer circumference of a grindwheel 1. It advances from the point D along a thread 2 in an inclination direction, and it advances by a rapid traverse from a point E on the line P to a point F. It advances from the point F in the direction of X to a point G, and it advances from the point G along the inclination direction of the thread 2 to a point H. It advances to a point I (at the outer circumference of the grindwheel) at the dress grinding speed. It advances from the point I in the direction of X to a point J, it retracts from the point J in the direction of Y to a point K, and it advances at the rapid traverse speed from the point K to the point L. It goes inversely from the point L in the direction of X, and it returns to the original point A, where one cycle is completed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the dressing of a grindstone, in which the speed of movement of the grindstone and dresser on the locus of movement during dressing of the grindstone is controlled, thereby efficiently dressing the grindstone.

0002

2. Description of the Related Art For example, the outer periphery of a grindstone must be dressed in the shape of a thread for thread grinding. In this case, the grindstone and dresser are moved in the X and Y directions, and the dresser is run along a predetermined trajectory, but in the prior art, the speed of movement was constant.

0003

Problems to be Solved by the Invention When the speed of movement of the dresser along the trajectory path is constant, the following problems occur. In other words, when dressing the outer periphery of a grinding wheel into a threaded shape, it is impossible to suddenly position the dresser at a predetermined grinding position and dress the entire thread, so it is necessary to cut in little by little and dress the entire thread. Become. On the other hand, since the grindstone and dresser perform dress grinding while repeating a cycle of moving along a predetermined locus path, dress grinding is performed only on a portion of the locus path at the beginning of dressing. That is, no dress grinding is performed in the remaining portion. Dress grinding time is the time it takes for the grindstone and dresser to move along the path multiplied by the number of cuts, but the dress grinding time actually accounts for only a small percentage of the total time, and is wasted time. The problem of waste arises. Since dressing of a grindstone generally takes a long time (about 3 hours), saving the above-mentioned wasted time is an extremely effective means for improving work efficiency.

The present invention was devised in view of the above circumstances, and provides a dressing control for a grinding wheel that minimizes wasted time during dressing grinding, shortens dressing grinding time, and improves machine operation rate. The purpose is to provide a method.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention moves the relative positions of the grindstone and the dresser in the X and Y directions along a predetermined trajectory, and dresses the outer periphery of the grindstone. In the control method, an imaginary line is set close to the grinding surface of the grinding wheel, and dressing is performed at a predetermined dressing grinding speed on the side of the grinding wheel where the locus of dressing forming exceeds the imaginary line, and a trajectory that does not exceed the imaginary line is set. The present invention is characterized by a grindstone dressing control method in which a control program for the control means is set so as to rapidly advance the path.

[0006]

[Operation] An imaginary line is set at a position close to the grinding surface of the grinding wheel. For example, when the dresser crosses the imaginary line and approaches the grinding wheel, it is moved on the locus path at the normal dress grinding speed. On the other hand, if the position is below the imaginary line, dress grinding is not performed, and therefore the workpiece is moved in rapid traverse along the trajectory path. With the above, wasted time can be reduced and dress grinding time can be shortened.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the grindstone 1 is supported by a grindstone stand main body 3, and is moved in the Y-axis direction by a grindstone motor 4 (hereinafter referred to as motor M1). On the other hand, the dresser 5 is fixed to the table 6 side, and the table moving motor 7 (hereinafter, motor M2
) moves in the X-axis direction. Of course, depending on the type of grinder, only the dresser 5 side moves in the X and Y axis directions, but for the sake of explanation, it is assumed that the grindstone 1 and the dresser 5 move as described above.

Motor M1 and motor M2 are controlled by a control device 8 (
(hereinafter referred to as NC8). Manual or automatic programming commands are input to NC8. The motors M1 and M2 are controlled to move the grindstone 1 and the dresser 5 in the Y-axis and X-axis directions by a predetermined movement amount and movement speed based on programming commands input into the NC 8.

As shown in FIG. 2, threads 2 corresponding to thread grooves are dress-molded on the outer periphery of the grindstone 1. Of course, the grindstone 1 may be used for internal grinding, but in this embodiment, a grindstone 1 for external grinding will be described.

[0010] To dress the thread 2 of the grindstone 1,
As described above, the grindstone 1 side and the dresser 5 side move in the Y-axis and X-axis directions, but for convenience of explanation, it is assumed that the grindstone 1 remains stationary and the dresser 5 side moves. Since it is dangerous for the dresser 5 to come into contact with the grindstone 1 during dress forming, an imaginary line PP (hereinafter referred to as line P) is set at a position close to the outer periphery of the grindstone 1. The gap δ between the line P and the outer periphery of the grinding wheel 1 is usually 2 mm to 3 mm.
The value of is set.

FIG. 3 shows the trajectory path 9 of the dresser 5 for dressing the thread 2. That is, dresser 5
is first at point A (starting point), moves toward line P to point B, and further moves to point C, which corresponds to the grindstone outer circumferential line. The process proceeds from point C to point D in the X direction, and the outer periphery of the grindstone 1 is ground. From point D, proceed along the thread 2 in an inclined direction, cross point E on line P, and proceed to point F. G from point F to X direction
Proceed to point G and move along the inclination direction of screw thread 2 to point H (
(on line P) and point I (point on the outer periphery of the grinding wheel). Proceed from point I to point J along the X direction, retreat from point J in the Y direction, and proceed to point K (on line P) and point L. From point L, move backward in the X direction, return to the original point A, and complete one cycle.

Next, the dressing control method will be explained. Regarding the control method, a description of the control circuit will be omitted since it is based on normal programming control. FIG. 3 shows the grinding start state. That is, the dresser 5 advances at a fast forward speed from point A, which is the starting point, to point B. To clearly display fast forwarding, the fast forwarding portion is shown with a dotted line. When the dresser 5 reaches the line P, the dressing grinding speed becomes normal and progresses from point B to point C. Note that the portion fed at the dress grinding speed is shown by a solid line. Point C is a position corresponding to the outer periphery of the grindstone 1. Next, the dresser 5 advances from point C to point D at the dress grinding speed, and from point D to point E on line P along the inclination direction of the thread 2 at the dress grinding speed. The dresser 5 advances at a rapid traverse speed from point E to point F, and also advances between points F and G and between points G and H at a rapid traverse speed. It progresses at the dress grinding speed from point H on line P to point I, which corresponds to the outer periphery of grinding wheel 1, and from point I to point J along the X direction at the same speed, and until point K on line P. Proceed along the Y direction at dress grinding speed. From point K to L
The dresser 5 advances at a rapid traverse speed from the point and point L to the original point A. As mentioned above, only the part beyond line P,
The dresser 5 is program-controlled by the NC 8 so as to be fed at the dress grinding speed.

FIG. 3 shows a state in which dress grinding is started, and the outer periphery of the grindstone 1 is not dressed at all. FIG. 4 shows a case where the thread 2 is dress-molded halfway. At the same time as above, the part below line P, that is, between A and B', E'
-F, F-G, G-H', K'-L, and LA-A, the dresser 5 is fed at a rapid traverse speed. On the other hand, line P
In other words, the locus paths beyond B'-C, C-D-M-E', H'-N-I-J, and J-K' are fed at the dress grinding speed. As a result of the above, the CD of grindstone 1
A portion of the MNI is threaded. FIG. 5 shows a state in which the threads 2 of the grindstone 1 are completely dress-molded. In this case, only the sections between A and B'', between K'' and L, and between LA and A are fast-forwarded,
For all other parts, the dresser 5 is fed at the dress grinding speed.

As described above, since the dresser 5 is moved at a rapid traverse speed in the portion of the locus path 9 of the dresser 5 where dress grinding of the grindstone 1 is not performed, the overall dress grinding time can be saved. In this embodiment, the thread 2 having the shape shown in the drawings has been described, but the shape of the thread is not limited thereto. Further, as described above, a similar dressing control method is applied to the case of a grindstone for internal grinding.

[0015]

[Effects of the Invention] According to the present invention, the following effects can be achieved. (1) Only the portion of the trajectory path necessary for dress grinding is fed at a predetermined dress grinding speed, and the other portions are fed at a rapid feed speed, so the overall dressing forming time can be greatly shortened. As an experimental example, the dress forming time of about 3 hours was shortened to 1 hour. (2) Since the dressing control is performed by normal programming control, it is only necessary to change and set the program commands according to the shape of the thread, and it is extremely easy to perform.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view for explaining the relative movement relationship between the grindstone and the dresser in this embodiment.

FIG. 3 is a partial cross-sectional view for explaining the operation of this embodiment.

FIG. 4 is a partial cross-sectional view for explaining the operation of this embodiment.

FIG. 5 is a partial cross-sectional view for explaining the operation of this embodiment.

[Explanation of symbols]

1 Grindstone 2 Screw thread 3 Grindstone main body 4 Grindstone motor (motor M1) 5 Dresser 6 Table 7 Table movement motor (motor M2) 8 Control device (NC) 9 Trajectory path

Claims (1)

[Claims] 1. A control method for dressing the outer periphery of a grindstone by moving the relative position of a grindstone and a dresser in the X and Y directions along a predetermined locus, the method comprising: setting an imaginary line close to the grinding surface of the grindstone; A control program of the control means is set to perform dressing at a predetermined dressing grinding speed on the grinding wheel side where the trajectory of dressing forming exceeds the imaginary line, and to perform fast forwarding on the trajectory path that does not exceed the imaginary line. How to control the dressing of the grinding wheel.