JP2014073552A - Grinding machine - Google Patents

Abstract

A grinding machine capable of truing without moving a reference surface is provided.
[Solution]
A reference member 16 having a reference surface 16a that can contact the truing roll 8 by feeding the truing roll 8 in the U-axis direction and forms a predetermined angle with the U-axis direction is provided.
A calculation unit 36 is provided that calculates the diameter of the truing roll based on the feed position of the U-axis where the truing roll 8 and the reference surface 16a are in contact.
By using the value of the diameter of the truing roll, the relative position of the grinding wheel 11 and the truing roll 8 is determined and moved relative to each other, so that the grinding surface of the grinding wheel 11 is trued.
[Selection] Figure 2

Description

  The present invention relates to a truing method for a grinding wheel of a grinding machine, and more particularly, to a grinding machine that measures the diameter of a truing roll and positions the truing roll using the value.

It is important from the viewpoint of ensuring the sharpness of the grinding wheel and the life of the grinding wheel that the cutting amount of the truing roll with respect to the grinding wheel during truing is set to the minimum necessary value. On the other hand, when truing is performed, the truing roll is worn, the diameter of the truing roll is changed, and as a result, the truing action position is changed. For this reason, it is important to always accurately grasp the diameter of the truing roll and accurately manage the cutting position of the truing roll, and the diameter of the truing roll is measured by the following method.
A reference member having a reference surface is arranged on the axis of feeding of the truing roll passing through the center of rotation of the truing roll, and is fed until the outer peripheral surface of the truing roll comes into contact with the reference surface. The diameter of the truing roll is calculated from the feed position of the rotation center of the truing roll when both are in contact (for example, Patent Document 1).

JP 2011-212782 A

In the prior art, the reference surface is arranged on the feed axis passing through the center of rotation of the truing roll when measuring the truing roll diameter. For this reason, it is necessary to move the reference surface to a position where it does not interfere with the truing roll during truing, an error in the reference surface position accompanying this movement occurs, and the measurement accuracy of the truing roll diameter decreases.
The present invention has been made in view of the above circumstances, and an object thereof is to provide a grinding machine capable of truing without moving a reference surface.

In order to solve the above-mentioned problem, the feature of the invention according to claim 1 is provided with a moving means for relatively moving a truing roll and a grinding wheel that are rotationally driven, and using the value of the diameter of the truing roll, the grinding wheel In a grinding machine for truing the grinding working surface of the grinding wheel, by determining the relative position of the truing roll and relative movement,
Feed means for feeding the truing roll in a feed axis direction orthogonal to the rotational axis of the truing roll;
A reference member having a reference surface that forms a predetermined angle with the feed axis direction and that contacts a truing action surface of the truing roll when the truing roll is at a predetermined position in the feed axis direction;
A calculating means for calculating a diameter of the truing roll using a value of the predetermined position;

  A feature of the invention according to claim 2 is that, in the invention according to claim 1, the truing roll, the feeding means, and the reference member are provided on a turntable.

  A feature of the invention according to claim 3 is that, in the invention according to claim 1 or claim 2, the reference member is disposed below the rotational axis of the truing roll.

  According to the invention of claim 1, since the amount of change in the feed position where the reference surface and the truing roll contact is larger than the amount of change in the radius of the truing roll, the error in the truing roll diameter due to the error in the feed position is small. Thus, the truing diameter can be accurately calculated. Therefore, it is possible to provide a grinding machine with good shape shaping accuracy of a grinding wheel by truing.

  According to the second aspect of the present invention, it is possible to provide a grinding machine capable of easily carrying out an arc-shaped truing on the grinding wheel by turning the turning table and setting an accurate arc radius.

  According to the invention which concerns on Claim 3, since a reference | standard member does not become an obstacle of truing roll replacement | exchange, the grinding machine with easy truing roll replacement | exchange can be provided.

It is a top view which shows the whole structure of the grinding machine of this embodiment. It is a perspective view which shows the whole truing apparatus of this embodiment. It is a figure which shows the condition which measures the truing roll diameter of this embodiment. It is a figure which shows the relationship between the truing roll diameter and feed position of this embodiment. It is a flowchart figure of the truing roll diameter measurement process of this embodiment. It is a figure which shows the relationship between the grinding wheel at the time of truing and a truing roll. It is A arrow directional view of FIG. It is a flowchart figure of the truing process of this embodiment.

Hereinafter, an embodiment of the present invention will be described based on an example in which an arc-shaped truing is performed on a grinding wheel of an internal grinding machine that grinds an inner circumferential raceway surface and the like of a bearing outer ring.
As shown in FIG. 1, the internal grinding machine 1 includes a bed 2, and on the bed 2, a feed device 3 that feeds a base 4 in the X-axis direction by rotation of a feed motor 12, and a Z-axis orthogonal to the X-axis. A grinding wheel base feeding device 9 is provided in the direction to feed the grinding wheel base 10 by the rotation of the feed motor 13. On the base 4, a main shaft 5 that rotatably holds the workpiece W and a turning table 6 that is turned around a B axis orthogonal to the X axis and the Z axis by a turning motor (not shown). A truing device 7 that rotationally drives a truing roll 8 is provided on the swivel table 6. The grinding wheel base 10 includes a rotation motor (not shown) that rotatably supports the grinding wheel 11 and rotates the grinding wheel 11.
With the above configuration, the main shaft 5 and the truing device 7 are fed by the feed device 3 in the X-axis direction with respect to the grinding wheel 11. Further, the grinding wheel 11 is fed in the Z-axis direction by the grinding wheel platform feeder 9, and the grinding wheel 11 comes into contact with the grinding position where the grinding wheel 11 contacts the inner peripheral machining surface of the workpiece W and the outer periphery of the truing roll 8. Indexed to the truing position.

  As shown in FIG. 2, the truing device 7 includes a truing body 71 supported by a guide 72 fixed on the turntable 6 so as to be capable of reciprocating in the U-axis direction parallel to the X-axis. Is fed in the U-axis direction by a feed screw 74 that is rotationally driven by Here, the truing roll 8 is held at a position where the truing roll 8 passes over the turning center P of the turning table 6 when fed in the U-axis direction. Further, the reference member 16 is disposed on the turntable 6 and on the passing path in the U-axis direction of the truing roll 8. The truing main body 71 includes an AE (acoustic emission) detection sensor 75 inside, and can detect an AE signal generated when the truing roll 8 contacts the reference member 16.

  The internal grinding machine 1 includes a control device 30 that performs automated grinding and truing by executing a predetermined program. As a functional configuration of the control device 30, an X-axis control unit 31 that controls the feed of the feed device 3, a Z-axis control unit 32 that controls the feed of the grindstone table feed device 9, and a B-axis control that controls the turning of the turning table 6. A unit 33, a U-axis control unit 34 that controls the feed of the truing device 7, and a grinding wheel shaft control unit 35 that controls the rotation of the grinding wheel 11. In addition, a calculation unit 36 that performs various calculations based on a preset calculation formula and a recording unit 37 that records various programs and data are provided.

A method for measuring the diameter of the truing roll 8 will be described with reference to FIGS.
In the side view of the truing device 7 shown in FIG. 3, the distance in the U-axis direction between the turning center P of the turning table 6 and the rotation center Q of the truing roll 8 is defined as the feed position of the U-axis. Since the reference member 16 is disposed on the feed path of the truing roll 8, the reference surface 16a and the outer peripheral surface of the truing roll 8 are in contact at a predetermined U-axis feed position.
This contact position differs depending on the diameter of the truing roll 8, and the relationship between the diameter of the truing roll 8 and the contact position can be expressed as shown in FIG. In FIG. 4, the movement axis n of the rotation center Q of the truing roll 8 and the extension line m of the reference surface 16a intersect at an inclination angle Θ of the reference surface 16a, and the intersection is a point M. Let L be the distance in the U-axis direction between the point M and the turning center P. Assuming that the radius of the truing roll 8 is rt and the feed position of the U-axis at the time of contact between the reference surface 16a and the truing roll 8 is Uk ₁ , the equation rt / sinΘ = Uk ₁ + L is established. Accordingly, the radius rt of the truing roll 8 can be calculated by the equation rt = (Uk ₁ + L) · sin Θ, and the inclination angle Θ and the distance L between the point M and the turning center P in the U-axis direction are constant. The radius rt of the truing roll 8 can be calculated by detecting the feed position Uk ₁ of the U axis when the truing roll 8 is in contact. The U-axis feed position is always recorded in the U-axis control unit 34 and can be read at any time.

A specific measuring process of the truing roll diameter will be described based on the flowchart of FIG.
The values of the inclination angle Θ of the reference surface 16a and the distance L between the intersection M and the turning center P, which are obtained by measurement in advance, are recorded in the recording unit 37.
The truing roll 8 is rotated (S1). The U-axis is driven to position the truing roll 8 to the truing roll diameter measurement start position Uk (S2). The truing roll 8 is advanced by step feed by ΔU (S3). It is confirmed whether the AE sensor 75 has detected an AE signal. If not confirmed, the process moves to step S3 and step-feeds again. If confirmed, the process moves to step S5 (S4). The current position Uk ₁ of U-axis is recorded in the recording unit 37 (S5). The truing roll diameter rt is calculated by the calculation unit 36 using the formula rt = (Uk ₁ + L) · sin Θ and recorded in the recording unit 37 (S6).
According to the measuring method of the truing roll diameter as described above, the change amount of the U-axis contact position is larger than the change amount of the truing roll diameter. For this reason, the diameter error is smaller than the U-axis feed error, and the measurement accuracy of the truing roll diameter is improved. Further, by disposing the reference member 16 below the truing roll 8, it is possible to prevent the reference member 16 from interfering with the replacement of the truing roll 8.

Next, a method of truing the grinding action surface in the cross section including the rotation center of the grinding wheel 11 into an arc having a central angle α will be described with reference to FIGS. 6 and 7.
In the side view of the truing device shown in FIG. 6, the radius of the truing roll 8 is rt, the radius of the grinding wheel 11 is rw, and the arc radius of the truing of the grinding wheel 11 is rs. In addition, the origin position of the X axis is the position of the rotation center O of the grinding wheel 11, and the X axis
The reference position of (Table 4) is the turning center P of the turning table 6, and the X-axis feed position is represented by the distance between the rotation center O and the turning center P in the X-axis direction.
The truing roll 8 is positioned at the feed position Ut calculated by Ut = rt + rs. Here, the reference member 16 is disposed at a position where the truing roll 8 and the reference member 16 do not contact each other. Next, the table 4 is positioned at Xt calculated by Xt = rw−rs, and the outer periphery of the grinding wheel 11 and the truing roll 8 comes into contact with each other. In this state, as shown in FIG. 7, the truing roll 8 is caused to reciprocate circularly between 8 ′ and 8 ″ of the central angle α by the peristaltic motion of the turning table 6, thereby setting the radius rs around the outer periphery of the grinding wheel 11. Arc-shaped truing can be performed.

A specific truing process will be described with reference to the flowchart of FIG.
The values of the angle α of the central angle of the arc shape of the truing and the radius rs of the arc are input to the recording unit 37 in advance.
The truing roll 8 is rotated (S1). The U-axis is driven to position the truing roll 8 to the truing start position Ut (S2). The Z axis is driven to position the grinding wheel 11 to the truing start position Zt facing the truing roll 8 (S3). The X axis is driven to position the turning center P of the table 4 to the truing start position Xt. Here, the value of Xt is a value obtained by subtracting the arc radius rs from the radius rw of the grinding wheel 11 (S4). The table 4 is advanced by ΔX _{1 by} step feed, and the truing roll 8 is cut into the grinding wheel 11 (S5). It is confirmed whether the AE sensor 75 has detected an AE signal. If not confirmed, the process moves to step S5 and step-feeds again. If confirmed, the process moves to step S7 (S6). The B axis is driven, and the truing roll 8 is turned α / 2 clockwise. By this operation, the truing roll 8 is positioned at the position 8 ″ shown in FIG. 7 (S7). The B-axis is driven to cause the truing roll 8 to turn α in the counterclockwise direction. It is positioned at a position of 8 'shown in (S8). table 4 is advanced by a step feed [Delta] X _2, cut into a truing roll 8 to the grinding wheel 11 (S9) to drive the .B shaft, truing roll 8 As a result of this operation, the truing roll 8 removes the grinding surface of the grinding wheel 11 by ΔX _{2 in the} X-axis direction and is positioned at the position 8 ″ (S10). The table 4 is retracted and the turning center P is positioned at the truing start position Xt (S11). The B axis is driven and the truing roll 8 is turned α / 2 counterclockwise. By this operation, the truing roll 8 is positioned at the position 8 shown in FIG. 7, and the rotation axis of the truing roll 8 and the rotation axis of the grinding wheel 11 become parallel (S12). The value of the radius rw of the grinding wheel 11 is calculated by the calculation unit 36 using the formula rw = Xt + rs−C · ΔX ₁ −ΔX _2, and the value of rw of the recording unit 37 is rewritten. Here, C is a number of repetitions of step feed [Delta] X ₁ in step S5 (S13).

  According to the above truing method, the error of the radius rs of the truing arc is the sum of the feed error of the U axis and the error of the radius rt of the truing roll 8 and does not include other factors. The error in measuring the truing roll diameter is the sum of the U-axis feed error and the AE sensor detection error, and does not include other factors. As a result, if the detection error of the AE sensor is excluded, the radius rs of the truing arc can be determined with an accuracy substantially equal to the feed accuracy of the U axis, and a desired accuracy can be easily ensured.

In this embodiment, the reference member 16 is fixed to the turning table 6, but it may be fixed to the side surface of the grindstone table 10. In this case, the grindstone is driven by driving the Z-axis to a position where the reference member and the truing roll 8 face each other. After positioning the table 10, a measuring process of the diameter of the routing roll is performed.
Further, although the contact between the truing roll 8 and the reference member 16 is detected by the AE signal, it may be detected by a power change of a motor that drives the truing roll 8.

W: Workpiece 3: Feeding device 4: Base 6: Turning table 7: Truing device 8: Truing roll 9: Grinding wheel table feeding device 10: Grinding wheel table 11: Grinding wheel 16: Reference member 30: Control device 31: X axis control Unit 32: Z-axis control unit 33: B-axis control unit 34: U-axis control unit 36: Calculation unit 37: Recording unit

Claims (3)

A moving means for relatively moving the truing roll and the grinding wheel that are rotationally driven, and by using the value of the diameter of the truing roll to determine the relative position of the grinding wheel and the truing roll, In a grinding machine to truing the grinding surface of the grinding wheel,
Feed means for feeding the truing roll in a feed axis direction orthogonal to the rotational axis of the truing roll;
A reference member having a reference surface that forms a predetermined angle with the feed axis direction and that contacts a truing action surface of the truing roll when the truing roll is at a predetermined position in the feed axis direction;
A grinding machine provided with a calculating means for calculating the diameter of the truing roll using the value of the predetermined position.   The grinding machine according to claim 1, wherein the truing roll, the feeding means, and the reference member are provided on a turning table.   The grinding machine according to claim 1 or 2, wherein the reference member is disposed below a rotation axis of the truing roll.

Images