JP2997930B1 - Method for preventing collision between a grinding wheel head side part and a work table side part in CNC cylindrical grinding machine - Google Patents

Abstract

A collision between a grinding wheel head side part p1 and a work table side part p2 when turning an upper table 6 to an arbitrary angle θ position is reliably and labor-savingly avoided. SOLUTION: A measuring device 10 for measuring a turning angle θ of an upper table 6 forming a part of a work table 2 is provided, and an approach between a grinding wheel side part p1 and a work table side part p2 based on the measurement information. To block.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing a collision between a grinding wheel head side part and a work table side part in a computer numerically controlled (hereinafter referred to as CNC) cylindrical grinding machine.

[0002]

2. Description of the Related Art In a CNC cylindrical grinder, in order to avoid a collision between a grinding wheel head side part and a work table side part, the grinding wheel head and the work table are prevented from approaching beyond an allowable limit. More specifically, an x-axis direction allowable movement range of the grinding wheel head related to the moving position of the work table and a z-axis direction allowable moving range of the work table related to the moving position of the grinding wheel head are set. The tables can be moved only within their respective movement tolerances.

However, since each of the above-mentioned movable ranges is determined on condition that the upper table forming a part of the work table is fixed to be parallel to the z-axis, When used in a state where is turned, there is no longer any possibility that it will work accurately, and the collision may occur. For this reason, when turning and using the upper table, it is necessary for the operator to work while paying close attention to avoid the collision.

[0004]

SUMMARY OF THE INVENTION According to the present invention, when the above-mentioned upper table is rotated and used for taper grinding or the like, the collision between the grindstone-side part and the worktable-side part is determined by an operator. The purpose is to be able to avoid it without care.

[0005]

According to the present invention, there is provided a measuring device for measuring a turning angle of an upper table which forms a part of a work table, and a grindstone side is measured based on measurement information of the measuring device. Implement so as to prevent the part and the worktable side part from approaching beyond the allowable range.

More specifically, the measuring device is provided,
In connection with the measurement information of this measuring device, the operation is performed so as to specify the x-axis direction allowable movement range of the grinding wheel head and the z-axis direction allowable movement range of the work table. Alternatively, the positional relationship between the specific portion on the grinding wheel side and the specific portion on the work table is determined based on the measurement information of the measuring device, and the positional relationship information prevents the specific portions from approaching beyond the allowable range. It is carried out as follows.

[0007] Thus, even if the upper table is used while being turned at an arbitrary angle, the collision between the grinding wheel head side part and the work table side part is mechanically avoided.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. FIG. 1 is a plan view of a CNC cylindrical grinding machine according to the present invention, and FIG. 2 is a front view of the grinding machine. In these figures,
1 is a bed, 2 is a work table movable on the bed 1 in the z-axis direction, and 3 is a grindstone head movable on the bed 1 in the x-axis direction.

The work table 2 comprises a lower table 4 guided by the bed 1 and an upper table 6 mounted on the upper surface of the lower table 4 so as to be able to rotate around a predetermined vertical axis 5. At this time, a headstock 7 and a tailstock 8 are mounted on the upper surface of the upper table 6. The grindstone table 3 is provided with a rotating grindstone 9 so as to be rotatable.

When grinding the work, the headstock center 7a
After the work is fixed between the tailstock center 8a and necessary information is input to the CNC device, the grinding process is started. Thereby, for example, the rotary grindstone 9 is rotated, the main shaft 7b of the headstock 7 is rotated, and the work is rotated. The rotating grindstone 9 is pressed at a required angle to a required portion of the work by moving the grindstone table 3 in the x-axis direction, etc.
The required grinding is performed.

The grinding machine according to this embodiment operates under the condition that the upper table 6 is turned in a counterclockwise direction.
When the worktable 2 is moved beyond a certain range, the specific part p1 on the grinding wheel side and the specific part p on the worktable side are moved.
2 occurs, and it is necessary to prevent this.

For this reason, the present embodiment is configured as follows. That is, a measuring device (rotary encoder) 10 for measuring the turning angle of the upper table 6 around the fixed vertical axis 5 is provided at five fixed vertical axes of the lower table 4. Then, when the upper table 6 turns, the rotary encoder 10 measures the turning angle, continuously inputs the measurement information to the CNC device, and based on the measurement information, the grindstone head side specific portion p1 and the work table side. The positional relationship with the specific part p2 is determined each time the upper table is turned. The measuring device 10 detects a linear displacement at a location that changes in conjunction with the turning displacement of the upper table 6 and detects the linear displacement.
May be derived.

By the way, the mathematical expression used for the determination of the positional relationship is obtained, for example, as follows. That is,
As shown in FIG. 3, a zx coordinate system having the origin at the fixed vertical axis 5 which is the turning center of the upper table 6 is formed. In this coordinate system, when the turning angle of the upper table is zero,
It is assumed that the coordinate value of the point p3 located at the right end of the front edge of the upper table 6, which is the worktable-side specific portion, is (u, v).

At this time, a line segment m indicating the position of the front edge of the upper table 6 is expressed by the equation x = v. Now, when the upper table 6 is turned counterclockwise by a certain angle θ, the coordinate value of the point p4 located at the right end of the front edge of the upper table 6 becomes (uθ, vθ). Uθ and vθ are represented by the following equations. uθ = u · cos θ−v · sin θ (1) vθ = u · sin θ + v · cos θ (2)

A line segment m1 indicating the position of the front edge of the upper table 6 after the upper table 6 has been turned counterclockwise by a certain angle θ is represented by the following equation. x = z · tan θ + (v / cos θ) (3) Equation (3) is derived as follows. That is, (1),
Judging from equation (2), the following equation holds. z2 = z1 · cosθ−x1 · sinθ (4) x2 = z1 · sinθ + x1 · cosθ (5) Here, z1 and x1 are coordinate values of an arbitrary point p5 on the line segment m, z2 and x2 are the specific points p after the point p5 is turned counterclockwise around the constant vertical axis 5 by a constant angle θ.
6 is the coordinate value. At this time, the specific point p6 is the line segment m
1 above.

Since the equation of the line segment m is x = v, v is substituted for x1 in the equations (4) and (5).
Thus, the following equation is obtained. z2 = z1 · cos θ−v · sin θ (6) x2 = z1 · sin θ + v · cos θ (7)

From equation (6), z1 = (z2 + vsin)
θ) / cos θ. By substituting this equation into equation (7), an equation corresponding to the above equation (3) is obtained as follows. x2 = ((z2 + vsinθ) / cosθ) · sinθ + v · cosθ = z2 · tanθ + v / cosθ

Next, a ZX coordinate system in which the coordinate values of the fixed vertical axis 5 are (a, b) is formed. In the z-x coordinate system, the expression of the line segment m1 expressed by the expression (3) is as follows in the z-x coordinate system. That is, the relationship between the coordinate values in the above coordinate system is as follows. Z = z + a, X = x + b Therefore, z = Za, x = Xb. Here, z and x are coordinate values in the zx coordinate system, and Z and X are coordinate values in the ZX coordinate system. By substituting these relationships into equation (3), X-b = (Za) .tan θ + v / cos θ Therefore, the line segment m1 is expressed by the following equation. X = Ztan θ−a · tan θ / cos θ + b (8)

Next, conditions for preventing a collision between the line segment m1 and the specific portion p1 in the ZX coordinate system will be described in consideration of the equation (8). At this time, the specific part p1 on the grinding wheel side
Is a coordinate value in the ZX coordinate system (S, T).

First, a range in which the grinding wheel head 3 can move in the x-axis direction without causing the collision (a movable range of the grinding wheel head 3 in the x-axis direction) is expressed as follows. a) S <uθ + a (S <u · cos θ−v · sin
θ + a). T> (Sa) tan θ + v / cos θ + b (9) If the equation (9) is satisfied, the collision does not occur. b) S ≧ uθ + a (S ≧ u · cos θ−v · sin
θ + a). T> uθ · tan θ + v / cos θ + b (10) If the expression (10) is satisfied, the collision does not occur.

Next, the range in which the worktable 2 can move in the z-axis direction without causing the collision (the movable range of the worktable 2 in the z-axis direction) is expressed as follows. a) T> vθ + b (T> u · sinθ + v · cos
θ + b). The collision does not occur. b) T ≦ vθ + b (T ≦ u · sinθ + v · cos)
θ + b). S <(T−b) / tan θ−v / sin θ + a (11) If the equation (11) is satisfied, the collision does not occur.

The above equations (9), (10) and (1)
1) Equation and S <uθ + a, S ≧ uθ + a T> vθ +
Expressions such as b and T ≦ vθ + b are expressed as a specific portion p on the grinding wheel head side.
1 is a mathematical expression used to determine the positional relationship between 1 and the worktable-side specific portion p2.

By causing the CNC device to calculate these equations, the movable range of the grinding wheel head 3 in the x-axis direction related to the moving position of the work table 2 represented by the position of the constant vertical axis 5 is determined. In addition to specifying the movable range of the work table 2 in the z-axis direction related to the movement position of the work table 2, the grindstone table 3 and the work table 2 are controlled so as to be moved only within the corresponding movable ranges.

At this time, in order to prevent the specific part p1 on the grinding wheel head side and the specific part p2 on the work table side from approaching within a certain distance, the whetstone head 3 or the work table 2 is more appropriate than the limit of the corresponding movable range. An allowable limit is provided at a position on the movable side by a distance, a movable allowable range corresponding to each movable range is specified, and movement to a side outside the allowable range is restricted. The movement allowable range does not specify the movable range, for example, the expression (9),
It may be directly obtained from an expression obtained by adding a constant as an allowance for collision to an appropriate side of the right side or the left side such as Expressions (10) and (11).

Thus, during operation of the CNC apparatus, even if the upper table 6 is displaced, the specific portion p1 on the grindstone side and the specific portion p2 on the worktable side approach each other beyond the allowable range of movement. And their collisions are reliably prevented.

The above embodiment can be modified, for example, as follows. That is, in the above-described embodiment, the allowable movement range of the grinding wheel base 3 and the work table 2 is specified. However, without specifying such a allowable movement range, the whetstone base 3 and the work table 2 are moved within these allowable movement ranges. Is prepared from these position information, and the current position information of the grindstone table 3 and the worktable 2 always satisfies this conditional expression.
To be moved. The conditional expression at this time may be, for example, a modified expression of Expressions (9), (10), and (11).

In the above embodiment, the case where the specific part p1 on the grindstone side and the specific part p2 on the work table side which collide with each other due to the turning of the upper table 6 are points and lines. Such a collision can be prevented by a proper idea.

Further, a specific site p1, which may collide,
There may be a plurality of pairs of p2. In this case, the allowable movement range of the grindstone table 3 and the work table 2 is specified for each pair according to the above description. The work table 2 is moved only in an overlapping range of a plurality of allowable movement ranges corresponding to each.

[0029]

According to the present invention described above, it is possible to reliably and labor-savingly avoid collision between the grinding wheel base side portion and the work table side portion when the upper table is turned to an arbitrary angle position and used. Becomes

[0030]

[0031]

[Brief description of the drawings]

FIG. 1 is a plan view of a CNC cylindrical grinder according to the present invention.

FIG. 2 is a front view of the grinding machine.

FIG. 3 is an explanatory plan view of the grinding machine.

[Explanation of symbols]

 2 Work table 6 Upper table 10 Measuring device θ Rotation angle p1 Specific part on the grinding wheel side p2 Specific part on the work table side

Claims (3)

(57) [Claims] 1. A measuring device for measuring a turning angle of an upper table forming a part of a work table, wherein the turning angle of the upper table based on measurement information of the measuring device is θ, and the center of the table turning center is When the position coordinates are [a, b], the position coordinates of the specific portion on the grinding wheel side are [S, T], and the position coordinates of the specific portion on the work table side are [u, v], the specific portion of the grinding wheel side is the workpiece. The range in which the grinding wheel head can move in the x-axis direction without colliding with the specific part on the table side is defined as T> (u · cos θ−v · sin θ) tan θ + v / cos θ + b. A method for preventing a collision between a grinding wheel head side part and a work table side part in a CNC cylindrical grinding machine, wherein the method is carried out so as to prevent access beyond an allowable range. 2. A measuring device for measuring a turning angle of an upper table forming a part of a work table, wherein the turning angle of the upper table based on measurement information of the measuring device is θ, and the center of the table turning center is When the position coordinates are [a, b], the position coordinates of the specific portion on the grinding wheel side are [S, T], and the position coordinates of the specific portion on the work table are [u, v], the specific portion of the grinding wheel side and the work table are set. When the positional relationship with the side specific portion is S <u · cos θ−v · sin θ + a, the range in which the grinding wheel head can move in the x-axis direction without causing the grinding wheel side specific portion to collide with the worktable side specific portion. , T> (S−a) tan θ + v / cos θ + b, and the positional relationship between the specific portion on the grinding wheel side and the specific portion on the work table side is S ≧ u · cos θ−v · sin θ + a. The range in which the grinding wheel head can move in the x-axis direction without causing collision with the specific part on the table side is defined as T> (u · cos θ−v · sin θ) tan θ + v / cos θ + b. A method for preventing collision between a grinding wheel head side part and a work table side part in a CNC cylindrical grinding machine, which is performed so as to prevent approach beyond a range. 3. A measuring device for measuring a turning angle of an upper table forming a part of a work table, wherein a turning angle of the upper table based on measurement information of the measuring device is θ, and a center of the table turning center is When the position coordinates are [a, b], the position coordinates of the specific portion on the grinding wheel side are [S, T], and the position coordinates of the specific portion on the work table are [u, v], the specific portion of the grinding wheel side and the work table are set. When the positional relationship with the side specific part is T ≦ u · sin θ + v · cos θ + b, the range in which the work table can move in the z-axis direction without causing the work table side specific part to collide with the grindstone side specific part is as follows: S <(T−b) / tan θ−v / sin θ + a, and a CNC cylindrical grinder implemented to prevent the wheel head side part and the work table side part from approaching beyond an allowable range. To prevent collision between the wheel head side part and the work table side part in the above.