CN107160291B

CN107160291B - Grinding machine

Info

Publication number: CN107160291B
Application number: CN201710120264.4A
Authority: CN
Inventors: 山口智史; 牧内明; 牧野有司
Original assignee: JTEKT Corp
Current assignee: JTEKT Corp
Priority date: 2016-03-08
Filing date: 2017-03-02
Publication date: 2021-11-09
Anticipated expiration: 2037-03-02
Also published as: CN107160291A; JP6658119B2; JP2017159387A; DE102017104591A1

Abstract

The grinding machine (1) is provided with a grinding wheel (6) for grinding a workpiece (W); a coolant supply unit (8) that supplies coolant to the machining region (R); a displacement section (20) which is supported by the headstock body (3b) so as to be able to change the amount of projection from the end surface on the machining region (R) side of the headstock body (3b), and which moves a workpiece (W) placed in the machining region (R) from a position supported by the spindle (3a) to a position spaced from the spindle (3 a); and a sensor unit (40) that detects the amount of protrusion of the displacement unit (20) from the end surface of the headstock body (3b) that faces the machining region (R). The sensor unit (40) is disposed in a region opposite to the machining region (R) with respect to an end surface of the headstock body (3b) facing the machining region (R), and detects a portion of the displacement unit that does not protrude from the end surface facing the machining region of the headstock body.

Description

Grinding machine

Technical Field

The present invention relates to grinding machines.

Background

Japanese utility model publication No. 60-26901 discloses a headstock provided with a push-out member for pushing out a workpiece placed at a grinding wheel machining position to a carrying-in/out position of a transfer device. Japanese kokokoku publication No. 60-26901 describes a technique in which a regulating device is provided at a carrying-in/out position, and a workpiece at a machining position is conveyed to a position where the workpiece abuts against the regulating device by a pushing device.

Here, in the case where the workpiece is conveyed to the predetermined position by the pushing device, instead of using the restricting device described in japanese unexamined patent publication No. 60-26901, there is known a technique in which a sensor for detecting that the workpiece is conveyed to the predetermined position is disposed, and the conveying by the pushing device is performed before the workpiece is detected by the sensor. However, when a coolant is used for grinding by a grinding wheel, if the sensor is disposed in a state where the coolant is exposed at the machining position of the grinding wheel, the coolant may flow into the sensor, and the detection accuracy of the sensor may be lowered.

Disclosure of Invention

An object of the present invention is to provide a grinding machine including a sensor for detecting a position of a workpiece, the grinding machine being capable of preventing a reduction in detection accuracy of the sensor.

A grinding machine according to an aspect of the present invention includes: a spindle for supporting a workpiece in a machining region; a headstock body rotatably supporting the spindle; a grinding wheel for grinding the workpiece supported by the spindle; a coolant supply unit configured to supply a coolant to the machining region; a displacement section that is supported by the headstock body so that a projecting amount of the displacement section from an end surface of the headstock body facing the machining area can be changed, and that moves the workpiece placed in the machining area from a position supported by the spindle to a position spaced apart from the spindle; and a sensor unit that detects a protruding amount of the displacement unit from an end surface of the headstock body facing the machining area.

The sensor unit is disposed in a region on the opposite side of the machining region with respect to an end surface of the headstock body facing the machining region, and detects a portion of the displacement unit that does not protrude from the end surface of the headstock body facing the machining region.

According to the grinding machine of the above aspect, when grinding a workpiece, the coolant is supplied toward the machining region. In contrast, the sensor unit is disposed in a region opposite to the machining region with respect to the end surface facing the machining region of the headstock body, and detects a portion of the displacement unit that does not protrude from the end surface facing the machining region of the headstock body. Therefore, since the coolant can be prevented from flowing into the sensor unit, the detection accuracy of the sensor unit can be prevented from being lowered due to the coolant flowing into the sensor unit.

Drawings

Other features, elements, processes, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the present invention with reference to the accompanying drawings, in which reference numerals indicate elements of the present invention, and wherein,

fig. 1 is a diagram showing a structure of a grinding machine according to an embodiment of the present invention.

Fig. 2 is a front view of the headstock.

Fig. 3 is a cross-sectional view of the spindle stock taken along line III-III of fig. 2.

Detailed Description

Hereinafter, a grinding machine 1 as an example of an embodiment of the present invention will be described with reference to the drawings. The grinding machine 1 is a wheel slide traverse type grinding machine in which a wheel slide 5 is traversed (moved in the Z-axis direction) with respect to a base 2. Further, the workpiece W of the grinding machine 1 is a crankshaft.

In the grinding machine 1, a headstock 3 and a tailstock 4 are disposed on an upper surface of a bed 2 fixed to an installation surface. The headstock 3 is rotatably supported by a main spindle 3a with respect to a headstock body 3b, and the tailstock 4 is rotatably supported by a center 4 a. In the headstock 3, the main spindle 3a is rotationally driven by a motor 3c, and the workpiece W is supported by both ends of the main spindle 3a and the center 4 a.

A wheel slide 5 is provided on the upper surface of the base 2 so as to be movable in the Z-axis direction (the axial direction of the workpiece W) and the X-axis direction (the direction orthogonal to the axial line of the workpiece W). The wheel head 5 is moved in the Z-axis direction by a motor 5a and moved in the X-axis direction by a motor 5 b. A grinding wheel 6 for grinding the workpiece W is rotatably disposed on the wheel base 5, and the grinding wheel 6 is rotationally driven by a motor 6 a.

Further, a dimension determining device 7 for measuring the outer diameter of a grinding portion of the workpiece W and a coolant supply portion 8 for supplying a coolant to the grinding portion are disposed on the upper surface of the base 2. The coolant supply unit 8 supplies coolant to a nozzle (not shown) provided in the headstock 3, and the coolant is discharged from the nozzle toward the grinding portion. The grinding machine 1 is provided with a control device 9 for controlling the driving of the

motors

3c, 5a, 5b, and 6 a.

Next, the detailed structure of the headstock 3 will be explained. As shown in fig. 1, the headstock 3 includes a main shaft 3a, a headstock body 3b, and a motor 3 c. As described above, the main spindle 3a supports one end of the workpiece W. The main spindle 3a is rotatably supported by the headstock main body 3b in a state in which the tip of the main spindle 3a supporting the workpiece W is directed to a machining region R to be ground by the grinding wheel 6. The headstock body 3b is provided on the base 2 so that the direction of the tip of the spindle 3a can be adjusted.

As shown in fig. 2, a spindle 3a is disposed on an end surface of the headstock body 3b facing the machining region R, and a motor 3c is externally disposed on an end surface facing the opposite side of the machining region R. The motor 3c is a motor that applies a driving force for rotating the spindle 3a, and is disposed in a region opposite to the machining region R with respect to the headstock body 3 b. Further, in the headstock body 3b, a displacement device 10 for moving a workpiece W (see fig. 1) is disposed below the main spindle 3a and the motor 3 c. The displacement device 10 includes a displacement unit 20, a temporary receiving table 30, and a sensor unit 40.

As shown in fig. 3, the displacement section 20 is a hydraulic cylinder including a cylinder main body 21, a piston 22, and a rod 23, and is driven and controlled by the control device 9 (see fig. 1). A part of the rod 23 protrudes from an end surface facing the opposite side (left side in fig. 3) of the machining region R of the headstock body 3b, and the protruding portion is accommodated in the rod accommodating portion 24.

The piston 22 is housed so as to straddle the cylinder body 21 and the rod housing portion 24, and is connected to the rod 23 inside the rod housing portion 24. An extension portion 25 extending in a direction opposite to the extension direction of the rod 23 (the left direction in fig. 3) is connected to the piston 22, and a detection portion 26 extending downward is formed at the distal end portion of the extension portion 25. In fig. 3, the position of the extension portion 25 is indicated by a broken line. The extended arrangement portion 25 may be connected to the rod 23.

The piston 22 reciprocates in accordance with the oil pressure supplied to the cylinder main body 21, and the rod 23 and the detected portion 26 expand and contract in accordance with the reciprocation of the piston 22. Further, a sensor attachment portion 27 extending from the lever housing portion 24 in a direction opposite to the extending direction of the lever 23 (the left direction in fig. 2) is attached to the lever housing portion 24.

The temporary receiving table 30 is a portion that supports the workpiece W from below, and is always disposed in the machining region R. The temporary receiving table 30 is coupled to the tip of the rod 23, and the workpiece W supported by the temporary receiving table 30 moves integrally with the temporary receiving table 30 as the rod 23 expands and contracts.

The sensor unit 40 is a sensor that detects the amount of protrusion of the rod 23 from the surface of the headstock body 3b facing the machining region R, and includes a pair of proximity sensors 41 and 42. The pair of proximity sensors 41 and 42 are attached to the sensor attachment portion 27 at positions facing the region where the detection section 26 moves along with the expansion and contraction of the lever 23. That is, the sensor unit 40 is disposed in a region opposite to the machining region R with respect to the headstock body 3 b. The pair of proximity sensors 41 and 42 are arranged in parallel along the expansion and contraction direction of the rod 23, and one proximity sensor 41 is disposed closer to the machining region R than the other proximity sensor 42. Instead of the proximity sensors 41 and 42, a sensor such as an optical sensor or a detection ultrasonic wave may be used.

When the detection target portion 26 moving integrally with the lever 23 comes in front of one of the proximity sensors 41 while the lever 23 of the displacement portion 20 is extending, the one of the proximity sensors 41 detects the detection target portion 26 and transmits a detection signal to the control device 9. Upon receiving the detection signal from one of the proximity sensors 41, the control device 9 stops driving of the displacement section 20. Similarly, when the detection portion 26 comes in front of the other proximity sensor 42 during the contraction of the rod 23, the other proximity sensor 42 detects the detection portion 26 and transmits a detection signal to the control device 9. Upon receiving the detection signal from the other proximity sensor 42, the control device 9 stops driving of the displacement section 20.

The pair of proximity sensors 41 and 42 are fixed in a state of being inserted into the holes 27a and 27b formed in the sensor attachment portion 27, and the hole 27a into which one of the proximity sensors 41 is inserted is formed in an elongated hole shape whose longitudinal direction is the extending direction (the left-right direction in fig. 3) of the rod 23. Therefore, the one proximity sensor 41 can adjust the attachment position of the rod 23 in the expansion and contraction direction with respect to the sensor attachment portion 27.

In this way, the sensor unit 40 is disposed in a region opposite to the machining region R with respect to the headstock body 3b, and the pair of proximity sensors 41 and 42 detects the detected part 26 exposed from the headstock body 3b in a region opposite to the machining region R with respect to the headstock body 3b of the displacement unit 20. In this case, when grinding the workpiece W, the coolant discharged to the machining region R can be prevented from being sprayed to the sensor unit 40. Therefore, the detection accuracy of the sensor unit 40 can be prevented from being lowered. Further, since the cylinder main body 21 and the piston 22 in the displacement portion 20 are disposed below the motor 3c, it is possible to prevent a failure of the displacement portion 20 due to the coolant.

Further, since a part of the displacement section 20 and the sensor section 40 are disposed in a space formed below the motor 3c, the size of the headstock 3 as a whole can be prevented from becoming large. The sensor unit 40 is disposed in a region opposite to the machining region R with respect to the headstock body 3b in a state where the pair of proximity sensors 41 and 42 are exposed from the headstock body 3 b. Therefore, when a failure or the like occurs in the pair of proximity sensors 41 and 42, the replacement operation can be efficiently performed. In addition, since the one proximity sensor 41 is attached to the sensor attachment portion 27 in a state in which the position of the rod 23 in the extending/contracting direction can be adjusted, the position of the one proximity sensor 42 can be easily adjusted.

Next, the operation of the grinding machine 1 will be described. As shown in fig. 1 to 3, when the workpiece W is attached and detached, the tailstock 4 is separated from the headstock 3 as compared with the grinding process, the rod 23 is extended, and the temporary receiving table 30 is moved to a position separated from the headstock body 3 b.

After the workpiece W is placed on the temporary receiving table 30, the rod 23 is shortened to bring the temporary receiving table 30 close to the headstock body 3b, and the end of the workpiece W is brought into contact with the spindle 3 a. At this time, the control device 9 controls the driving of the displacement unit 20 to shorten the rod 23, and stops the driving of the displacement unit 20 when receiving a detection signal from the other proximity sensor 42. In fig. 2 and 3, the positions of the temporary receiving table 30, the extended portion 25, and the detection target portion 26 in a state where the rod 23 is contracted are indicated by two-dot chain lines.

Next, the tailstock 4 is brought closer to the headstock 3, and the workpiece W supported by the temporary support table 30 is supported at both ends by the main spindle 3a and the center 4a so as to be rotatable. Thereafter, the outer peripheral surface of the workpiece W is held by a chuck (not shown) provided in the headstock body 3b, and the workpiece W is ground by the grinding wheel 6.

As described above, the sensor unit 40 is disposed in the region on the opposite side of the machining region R with respect to the headstock body 3b, and detects the detected part 26, which is a portion of the displacement unit 20 exposed in the region on the opposite side of the machining region R with respect to the headstock body 3 b. This can prevent the coolant discharged to the machining region R from being sprayed to the sensor unit 40 during grinding of the workpiece W. Therefore, the detection accuracy of the sensor unit 40 can be prevented from being lowered. Further, since the cylinder main body 21 and the piston 22 are disposed below the motor 3c, it is possible to prevent the occurrence of a failure of the displacement portion 20 due to the coolant flowing into the cylinder main body 21 and the piston 22.

After the grinding process is completed, the tailstock 4 is moved in a direction away from the headstock 3. At this time, since the temporary receiving table 30 is disposed below the workpiece W, the workpiece W can be prevented from falling down with the movement of the tailstock 4. Thereafter, the rod 23 is extended to move the workpiece W in a direction away from the headstock 3, thereby replacing the workpiece W. At this time, the control device 9 controls the driving of the displacement unit 20 to extend the rod 23, and stops the driving of the displacement unit 20 when receiving a detection signal from one of the proximity sensors 41. A gantry loader or the like can be used to convey the workpiece W into the grinding machine 1.

In the above embodiment, the case where the motor 3c is externally provided on the end surface of the headstock body 3b facing the opposite side of the machining region R has been described, but the motor 3c may be housed inside the headstock body 3 b. In this case, the sensor unit 40 is preferably disposed in a space formed below the motor 3 c. In this case, since the sensor unit 40 is housed inside the headstock body 3b, the coolant can be reliably prevented from flowing to the sensor unit 40. Therefore, the occurrence of defects in the sensor unit 40 due to the coolant being poured can be prevented.

In the above embodiment, the case where the workpiece W is supported at both ends by the headstock 3 and the tailstock 4 has been described, but the workpiece W may be supported at both ends by 2 headstock 3. In this case, the chuck can be eliminated. In a state where the workpiece W is supported at both ends, the workpiece W may be rotationally driven from both sides, or the workpiece W may be rotationally driven from one side of the headstock 3.

As described above, the grinding machine 1 according to the embodiment of the present invention includes: a main spindle 3a for supporting a workpiece W in a machining region R; a headstock body 3b rotatably supporting the main shaft 3 a; a grinding wheel 6 for grinding the workpiece W supported by the spindle 3 a; a coolant supply unit 8 for supplying a coolant to the machining region R; a displacement unit 20 that is supported by the headstock body 3b so that the amount of projection from the end surface of the headstock body 3b toward the machining region R can be changed, and that moves the workpiece W placed in the machining region R from a position supported by the spindle 3a to a position spaced apart from the spindle 3 a; and a sensor unit 40 that detects the amount of protrusion of the displacement unit 20 from the end surface of the headstock body 3b toward the machining region R. In addition, in the grinding machine 1, the sensor unit 40 is disposed in a region opposite to the machining region R with respect to the end surface of the headstock body 3b facing the machining region R, and detects a portion of the displacement unit 20 that does not protrude from the end surface of the headstock body 3b facing the machining region R.

According to the grinding machine 1, the coolant is supplied toward the machining region R when the workpiece W is ground. On the other hand, the sensor unit 40 is disposed in a region opposite to the machining region R with respect to the end surface of the headstock body 3b facing the machining region R, and detects a portion of the displacement unit 20 that does not protrude from the end surface of the headstock body 3b facing the machining region R. Therefore, since the coolant can be prevented from flowing into the sensor unit 40, the detection accuracy of the sensor unit 40 can be prevented from being lowered due to the coolant flowing into the sensor unit 40.

In addition to the grinding machine 1 described above, the grinding machine 1 includes a temporary receiving table 30 which is connected to the displacement section 20, is always disposed in the machining region R, and supports the workpiece W detached from the main spindle 3 a. According to the grinding machine 1, the workpiece W detached from the main spindle 3a can be prevented from falling.

In the grinding machine 1 described above, the sensor unit 40 is disposed in a region on the opposite side of the machining region R from the headstock body 3 b. According to the grinding machine 1, the coolant can be prevented from being sprayed to the sensor unit 40. Therefore, the occurrence of defects in the sensor unit 40 due to the coolant being poured can be prevented.

In the grinding machine 1 described above, the sensor unit 40 is configured by the proximity sensors 41 and 42 capable of detecting the portions of the displacement unit 20 exposed to the headstock body 3b in the region on the opposite side of the machining region R. According to the grinding machine 1, when the proximity sensors 41 and 42 are broken down or the like, the proximity sensors 41 and 42 can be efficiently replaced.

In the grinding machine 1 described above, the headstock body 3b includes the motor 3c that applies a driving force for rotating the main spindle 3a, the motor 3c is provided in a state of being exposed in a region of the headstock body 3b on the opposite side of the machining region R, and the sensor unit 40 is disposed in a space formed below the motor 3 c. According to the grinding machine 1, since the empty space can be used as the arrangement space of the sensor unit 40, the increase in size of the headstock body 3b can be suppressed.

In the grinding machine 1 described above, the sensor unit 40 is disposed inside the headstock body 3 b. According to the grinding machine 1, the coolant can be prevented from being sprayed to the sensor unit 40. Therefore, it is possible to prevent the sensor unit 40 from being defective due to the coolant being poured.

In the grinding machine 1 described above, the headstock body 3b includes the motor 3c that applies a driving force for rotating the main spindle 3a, the motor 3c is housed inside the headstock body 3b, and the sensor unit 40 is disposed in a space formed below the motor 3 c. According to the grinding machine 1, since the empty space can be used as the arrangement space of the sensor unit 40, the increase in size of the headstock body 3b can be suppressed.

Claims

1. A grinding machine, comprising:

a spindle that supports a workpiece in a machining region;

a headstock body that rotatably supports the spindle;

a grinding wheel for grinding the workpiece supported by the spindle;

a coolant supply unit configured to supply a coolant to the machining region;

a displacement section that is supported by the headstock body so that a projecting amount of the displacement section from an end surface of the headstock body facing the machining area can be changed, and that moves the workpiece placed in the machining area from a position supported by the spindle to a position spaced apart from the spindle; and

a sensor unit that detects a protruding amount of the displacement unit from an end surface of the headstock body facing the machining area,

the sensor unit is disposed in a region opposite to the machining region with respect to an end surface of the headstock body facing the machining region, and detects a portion of the displacement unit that does not protrude from the end surface of the headstock body facing the machining region,

the sensor unit is disposed in a region on the opposite side of the machining region from the headstock body.

2. A grinding machine as claimed in claim 1 in which,

the machining apparatus further includes a temporary receiving table coupled to the displacement section, always disposed in the machining area, and configured to support the workpiece detached from the spindle.

3. A grinding machine as claimed in claim 1 in which,

the sensor unit is configured by a proximity sensor capable of detecting a portion of the displacement unit exposed to the headstock body in a region opposite to the machining region.

4. A grinding machine as claimed in claim 3 in which,

the headstock body includes a motor for applying a driving force for rotating the spindle,

the motor is provided in a state of being exposed in a region of the headstock body opposite to the machining region,

the sensor unit is disposed in a space formed below the motor.

5. A grinding machine, comprising:

a spindle that supports a workpiece in a machining region;

a headstock body that rotatably supports the spindle;

a grinding wheel for grinding the workpiece supported by the spindle;

a coolant supply unit configured to supply a coolant to the machining region;

the sensor unit is disposed inside the headstock body.

6. A grinding machine as claimed in claim 5 in which,

7. A grinding machine as claimed in claim 5 or 6 in which,

the motor is accommodated in the interior of the headstock body,

the sensor unit is disposed in a space formed below the motor.