JPH0627334Y2 - Numerically controlled grinding machine equipped with multiple grinding wheels - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a numerically controlled grinding machine capable of simultaneously forming a taper on a plurality of workpieces.

<Prior Art> Conventionally, in this type of numerically controlled grinding machine, a cam and a tappet come into contact with a workpiece in which two cams having the same phase and the same profile are close to each other like a camshaft of a twin cam engine. When forming a taper so as to make point contact, two grinding wheels of the same shape (hereinafter referred to as a multi-grinding wheel) are attached to the grinding wheel shaft, and the wheel head is angled by θG (according to the taper angle θW of the cam to be formed. = ΘW) Turn,
As shown in FIG. 6, the grinding wheels G1 and G2 of the multi-grinding wheel G
Surfaces S3, S facing the tapered surfaces S1, S2 of the workpiece W of
4 so that the distances X1 and X2 in the direction perpendicular to the workpiece axis O become equal to each other, the grindstone G1 is moved by a not-shown grindstone correcting tool in accordance with a template prepared in advance. The wheel G1 of the car G1 is corrected by the correction amount D to form a step on the multi-wheel.

<Problems to be Solved by the Invention> In such a conventional one, when forming a step on a multi-grinding wheel, it is necessary to replace the template of the grindstone correcting device according to the type of taper to be formed, and this template is replaced. The work is cumbersome and reduces workability.

<Means for Solving the Problems> The present invention has been made to solve the above-mentioned problems, and as shown in FIG. 1, a turning angle reading means 100 for reading the turning angle of the wheel head, This turning angle reading means 10
A turning direction determination means 101 for determining the turning direction of the grinding wheel base from the turning angle read by 0, a grinding wheel interval storage means 102 for storing the intervals between a plurality of grinding wheels, the turning angle detection means 100, and the grinding wheel interval. Correction amount calculation means 103 for calculating the correction amount of the grinding wheel from the storage means 102 such that the distances orthogonal to the workpiece center axis from the surface of the grinding wheel that faces the workpiece during turning are equal; It is characterized by comprising a grindstone correcting means 104 for correcting one of the adjacent grindstone wheels according to the calculated correction amount grindstone according to the turning direction judged by the turning direction judging means 101.

<Operation> Depending on the turning angle of the grinding wheel, the grinding wheel correction amount is calculated so that the distances orthogonal to the workpiece center axis from the surfaces of the grinding wheels that face the workpieces are equal, and the turning direction of the grinding wheel is calculated. Accordingly, the grindstone of the grindstone wheel corresponding to the grindstone correction amount is corrected by the grindstone to form a step.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 2, reference numeral 10 is a bed of a grinder, on which a headstock 11 and a tailstock 12 are mounted.

On the bed 10, a swivel shaft 40 for projectingly supporting the grindstone slide 45 is provided so as to swivel.

Each of the headstock 11 and the tailstock 12 has a center 1
5 and 16 are provided, the work W is sandwiched and supported between the centers 15 and 16, and the work W is rotationally driven via a drive fitting 18 by a main shaft 17 connected to a main shaft drive motor (not shown). It is supposed to be done.

The work table 13 is connected to a servo motor 21 via a screw feed mechanism including a ball screw 20 and is movable in the Z-axis direction parallel to the spindle axis O _s .

The grindstone slide 45 mounts the grindstone 14 so that the grindstone 14 can be moved back and forth in the X direction intersecting with the spindle axis O _s, and the grindstone mount 14 is provided with a screw feed mechanism including a ball screw 30 and a servo motor 31. It is controlled.

In addition, a grindstone base slide 45 on which the grindstone base 14 is placed.
Can be turned about the turning shaft 40 as a central axis by a servomotor 42 via a feed screw 41. Also, 42a
Is an encoder for detecting the inclination of the wheel head 14 from the rotation amount of the servo motor 42.

G is a multi-grinding wheel composed of adjoining grinding wheels G1 and G2 of the same shape, and is supported by a grindstone shaft 43 on the grindstone base 14.

Reference numeral 50 is a truing device for forming the grinding wheels G1 and G2, which is mounted on the grinding wheel base 14 and includes servo motors 51,
52 controls the tip position of the grindstone correction tool 50a via the feed screws 53 and 54.

FIG. 3 shows a control circuit for controlling the grinding machine having the above structure.

60 is the servomotor 21, 31, 42, 51, 52
It is a numerical controller for controlling the machining of the workpiece W by distributing pulses to the drive circuits 61X, 61Z, 61A, 61U, 61W for respectively driving the.

The numerical controller 60 includes an arithmetic processing unit 65, a memory M, and an interface 6 connected to the arithmetic processing unit 65.
6. A pulse generation circuit 67.

The interface 66 includes a data writing device 6
8. Display mounting 69 is connected.

The pulse generation circuit 67 includes an X axis, a Z axis, an A axis, and a U axis.
Pulse generators 67X, 67Z, 67A, 67U, 67W for independently distributing pulses to the axis and the W axis are provided to distribute the commanded number of pulses.

The memory M has a numerical control data area NCDA.
Is formed, and in this numerical control data area NCDA,
The machining program is written using the data writing device.

The operation when the grindstone correction command is read into the arithmetic processing unit 65 in the above configuration will be described with reference to FIG.

In step 200, the detected value of the encoder 42a is read and the turning angle θ of the grindstone base 14 is calculated. In step 201, it is determined from the turning angle θ calculated in step 201 whether or not the wheel head 14 has been turned. This judgment is Ye
In the case of s, the process proceeds to the next step 202, and the wheel head 1
The turning direction of 4 is determined. For example, if the turning state of the multi-grinding wheel G shown by the solid line in FIG. 6 is the positive direction (the opposite direction is the negative direction), if the determination is the positive direction, the process proceeds to the next step 203. Transition. In this step 203, it is determined whether or not the currently mounted multi-grinding stone G has already been corrected with the present turning angle θ in the positive direction. If this determination is No, the process proceeds to the next step 204, and it is further determined whether or not the multi-grinding stone G has been corrected in the negative direction. If this determination is No, the process proceeds to the next step 207 and the grinding wheel G
1 has a grinding wheel G for forming a step δ1 shown in FIG. 5 (a).
1 is deleted by the deletion amount C1. This step difference δ1 is calculated by the following arithmetic expression.

δ1 = L · Sin θ where L is the distance between the grinding wheels G1 and G2. When this grindstone correction is completed, the routine proceeds to the next step 206, where the grindstone wheels G1 and G2 are cut by a predetermined amount S, and the grindstone correction processing is completed.

If the determination in step 201 is No, the advancing / retreating direction of the grindstone 14 and the spindle axis O _s are the same as when machining a cylindrical workpiece.
Are orthogonal to each other, the process proceeds to step 206, and the grinding wheels G1 and G2 are cut by a predetermined amount S each.

If the determination in step 203 is Yes, it is determined that the grinding wheel G1 has already been stepped in the state of turning in the forward direction, and the process proceeds to step 206, where the grinding wheel G1
1 and G2 are cut by a predetermined amount.

Further, in the case of the judgment No in step 204, the grindstone base 1
4 is determined to have turned from the negative direction to the positive direction, the process proceeds to the next step 205, and as shown in FIG. 5 (b), in the grinding wheel G1, the grinding wheel head 14 has a turning angle θ2 in the negative direction. Since the step δ2 that is sometimes added to the grinding wheel G2 and the step δ3 corresponding to two steps (δ1 + δ2) at the current turning angle θ1 in the positive direction are added, the grinding wheel G1 is deleted by the deletion amount C2. The step δ3 is calculated by the following arithmetic expression.

δ3 = L · (Sin θ1 + Sin θ2) If the determination in step 202 is No, it is determined that the turning direction of the wheel head 14 is the negative direction, and steps 208 to 211 are performed.
Is processed. This processing is performed in steps 203 to 2 above.
The description is omitted because only the grinding wheel G1 of 07 is changed to G2.

By performing the above steps 200 to 211, it is possible to easily form a plurality of tapers on the adjacent workpieces having the same phase and the same profile by the multi-grinding stone G.

In this embodiment, the turning angle of the wheel head is calculated by reading the detected value of the encoder, but the command value instructed by the numerical control device may be read.

<Effects of the Invention> As described above, according to the present invention, when a plurality of tapers are formed on the workpiece, the wheel is corrected on one of the adjacent grinding wheels according to the turning angle of the grinding wheel to make a step. There is an advantage that the workability is not deteriorated in the correction work of the grinding wheel.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a block diagram for explaining the concept of the present invention, FIG. 2 is a numerical control grinder equipped with a multi-grinding stone of the embodiment, and FIG. Block diagram of a control circuit for controlling an example numerically controlled grinding machine, No. 4
5 and 5 are flowcharts showing the operation of the arithmetic processing unit in FIG. 3, and FIG. 6 is a diagram for explaining the correction of the grinding wheel. 10 ... Bed, 13 ... Work table, 14 ... Grindstone stand 21, 31, 42 ... Servo motor, 40 ... Rotation axis, 45 ... Grindstone stand slide, G ... Multi grindstone, G
1, G2 ... Grinding wheel, W ... Workpiece.

Claims (1)

[Scope of utility model registration request] 1. A slide supported on a bed so as to be rotatable about a rotation axis, a grindstone mounted on the slide so as to be able to advance and retreat, an advancing and retreating direction of the grindstone and this advancing and retreating direction. A whetstone correcting device movable in a direction orthogonal to
In a numerically controlled grinding machine equipped with a multi-grinding wheel consisting of adjacent grinding wheels of the same shape on a wheel head, a turning angle reading means for reading the turning angle of the wheel head and a turning angle read by the turning angle reading means A turning direction determining means for determining a turning direction of the grinding wheel base, a grinding wheel interval storage means for storing a distance between the plurality of grinding wheels, a turning angle reading means and the grinding wheel distance storage means for the turning of the grinding wheel base. Correction amount calculating means for calculating a correction amount of the grinding wheel such that distances orthogonal to the workpiece center axis from the surface of the grinding wheel facing the workpiece are equal, and in the turning direction determined by the turning direction determining means. Accordingly, a numerical control grinding machine having a multi-grinding wheel is provided with a grinding wheel correcting means for correcting one of the adjacent grinding wheel wheels with the calculated correction amount grinding wheel.