TW201817537A - Grinder - Google Patents

Abstract

Provided is a grinder that facilitates manual grinding work requiring careful operation. A grinder 1 has: a grindstone 4 that grinds a workpiece; a nozzle 71 through which a cooling liquid is jetted out to the workpiece; hand-feed handles 41, 42 that are operated by being rotated by an operator; a proximity sensor 53 that detects a proximate state between the workpiece and the grindstone 4; a control unit 50 that controls servo motors 61, 62 so as to bring the workpiece and the grindstone close to, or into contact with, each other at a speed corresponding to the rotational speeds of the hand-feed handles 41, 42; and notification devices (21, 31, 54) that notify the operator. The control unit 50 notifies the operator of the proximate state by using the notification devices in response to the proximate sensor 53, and either reduces the speed for bringing the workpiece W and the grindstone 4 close to each other with respect to the rotational speeds of the hand-feed handles 41, 42 before and after the proximate state, or temporarily stops the relative movement between the workpiece W and the grindstone 4 in the proximate state.

Description

   Grinder   

The invention relates to an NC machine tool with a manual feed handle. In the NC machine tool, the operator can relatively move the position of the grinding wheel relative to the workpiece by manual operation. Grinding machine for workability during handle operation.

For a numerical control (NC) machine tool having a manual feed handle that allows an operator to relatively move the position of the grinding wheel relative to the workpiece by manual operation, for example, Patent Document 1 describes a CNC (Computer numerical control) Grinding machine, which has a manual feed handle for table feeding and a manual feed handle for grinding table feeding, and a manual operation mode in which pulse generators are generated from each manual feed handle The pulse corresponding to the rotation amount is input to the control unit, and the control amount corresponding to the pulse is output from the control unit to the servo motor to move the position of the table or the grinding wheel.

In addition, conventional hydraulic grinders directly apply pressure to the hydraulic oil for moving the relative position of the grinding wheel with respect to the workpiece, and move the relative position of the grinding wheel with respect to the workpiece. An NC machine tool with a manual feed handle simulates the operating feel of this hydraulic grinder. For example, a grinder as shown in Patent Document 2 is known. In this grinder, when the distance between the grinding wheel and the workpiece is detected to be close, the torque of the manual feed handle is set to be variable, so that the operation of the manual feed handle feels heavy.

Similarly, Patent Document 3 discloses a technique in which an operator who uses a brake to make the handle operation feel resistance after the grinding wheel comes in contact with the workpiece can obtain a feeling similar to that when operating a handle of a hydraulic grinder.

    [Prior technical literature]         [Patent Literature]    

Patent Document 1: Japanese Patent Application Laid-Open No. 2006-123138

Patent Document 2: Japanese Patent Application Laid-Open No. 2015-157345

Patent Document 3: Japanese Patent Laid-Open No. 2001-38578

When the manual feed handle is operated to bring the grinding wheel close to the workpiece, the operator rotates the operation handle while confirming the preset coordinate value with the display device, so that the two do not collide, but if the When there is a difference between the actual value and the actual distance, the two may inadvertently make strong contact, which may cause adverse effects on the processing quality. Therefore, in fact, the grasp of the distance information between the grinding wheel and the workpiece is not just It is performed by confirming the coordinate values displayed on the display device, and also visually confirming the actual gap between the two, and then confirming the visual information of Mars and the like caused by the contact between the two. Be careful.

According to Patent Document 2, the manual feed handle allows the operator to feel the state where the grinding wheel is close to the workpiece in advance, and attempts have been made to provide the operator with further information on the sense of touch. However, as a means for making the torque variable, a brake pad is pressed against a shaft of a manual feed handle by a piston, which has a limitation in a response speed. In addition, exemplified aspects of the detection means for detecting a situation where the distance between the workpiece and the grinding wheel are close to each other include an acoustic wave sensor, a gap sensor, a distance measurement sensor, and the like. In a gap sensor, a distance measurement sensor, or the like, a proximity state based on a distance measurement value is detected in advance. Even if such a detection means is used to detect the approaching state, since the response speed of the means for changing the torque is slow, the grinding is completed when the operator feels the contact. On the other hand, in the case of using a sonic sensor, since the actual contact is detected instead of the approach of the workpiece to the grinding wheel, the grinding will be further advanced. In Patent Document 3, since the brake is applied to the handle after the contact is determined, the polishing is further advanced. Although a magnetic powder brake or the like is known as a means for varying the torque, there is also a limitation on the response speed.

An object of the present invention is to provide a grinder that can improve the workability of a manual grinding operation that requires careful operation.

In order to solve the above problems, the grinding machine of the present invention is characterized by comprising: a grinding wheel that grinds a workpiece; a nozzle that sprays a coolant on the workpiece; a manual feed handle that is operated by an operator to rotate; a proximity sensor that detects The approaching state of the workpiece and the grinding wheel; a moving device that moves the workpiece and the grinding wheel to change the relative position of the two; a control unit that controls the moving device so that the workpiece and the grinding wheel are at a speed according to the rotation speed of the manual feed handle Proximity / contact; and a notification device that notifies the operator, and the control unit responds to the detection information of the proximity sensor, and uses the notification device to notify the operator of the approach status, and before and after the approach status The speed at which the workpiece approaches the grinding wheel is reduced relative to the rotation speed of the manual feed handle, or the relative movement of the workpiece and the grinding wheel is suspended during the approaching state.

According to the present invention, when the grinding wheel is brought into a state immediately before contacting the workpiece, the feed speed is slowed down or paused, thereby avoiding the situation where the grinding wheel cuts into the workpiece at a constant speed to produce the homeopathic cutting. In addition, since the operator has been notified of the state immediately before the contact, the operator can know that there is a case where the speed mode is changed or a case where there is a pause.

1‧‧‧ grinder

4‧‧‧ Grinding Wheel

5‧‧‧Workbench

6‧‧‧ Grinding wheel table

7‧‧‧ spindle device

8‧‧‧ tailstock

10‧‧‧ Bed

21, 22, 23‧‧‧ display device

31,32,33‧‧‧Enter key

41,42‧‧‧Manual feed handle

50‧‧‧control unit

51,52‧‧‧Pulse generator

53‧‧‧ Proximity sensor

54‧‧‧Vibrator

56‧‧‧Drive unit

57‧‧‧Timer

58‧‧‧Memory

59‧‧‧ Flag

61,62‧‧‧Servo motor

71‧‧‧ Nozzle

72‧‧‧ Coolant

W‧‧‧ Workpiece

FIG. 1 is a perspective view illustrating the appearance of an embodiment of a grinding machine.

Fig. 2 is a system configuration diagram of a grinding machine.

FIG. 3 is a diagram showing an operation flow.

Hereinafter, the form for implementing this invention is demonstrated. FIG. 1 shows the appearance of the grinder 1. The grinding machine 1 includes a table 10, a work table 5, a grinding wheel 4, a grinding wheel table 6 that supports the grinding wheel 4, a spindle device 7, and a tailstock 8. In the drawing, the direction of the X axis indicates the direction in which the grinding wheel 4 cuts into the workpiece W, and the direction of the Z axis indicates the feed direction of the workpiece table 5. The X axis and the Z axis are orthogonal to each other. The grinder 1 includes display devices 21, 22, and 23 using a liquid crystal panel, various input keys 31, 32, and 33, a manual feed handle 41 in the X-axis direction, and a manual feed handle 42 in the Z-axis direction. The touch screen or touch panel can also be used to have the functions of the display devices 21, 22, 23 and the input keys 31, 32, 33. The display devices 21, 22, and 23 display a state where an operator inputs (sets) the grinder 1 or an operating state of the grinder 1 and the like. The various input keys 31, 32, and 33 accept inputs from the operator for switching between automatic operation mode and manual operation mode, and various settings. Among them, a display device 21 and an input key 31 are arranged near the manual feed handle 41 to input and output information related to the feed in the X-axis direction. In addition, a display device 22 and an input key 32 are arranged near the manual feed handle 42 to input and output information related to the feed in the Z-axis direction. The 71 series nozzle is used to spray the cooling liquid 72 between the workpiece W and the grinding wheel 4.

FIG. 2 is a diagram showing a system configuration of the grinder 1. The control unit 50 is a computer that executes a control program. Also, pulse generators 51, 52 are provided, which respectively convert the rotation of the manual feed handles 41 and 42 into pulses. The grinding wheel table 6 is moved in the X-axis direction by a servo motor 61 (corresponding to a moving device). The work table 5 is moved in the Z-axis direction by a servo motor 62 (corresponding to a moving device). With these moving devices, the workpiece W and the grinding wheel 4 are moved to change the relative positions of the two. Pulse generators 51 and 52 are connected to the control unit 50. In addition, the control unit 50 controls the servo motors 61 and 62 via the drive unit 56, and the display unit 21, 22, 23 and the input keys 31, 32, 33 are connected to the control unit 50. Light-emitting elements such as LEDs are installed in the input keys 31, 32, and 33. The control unit 50 can light the surfaces of the input keys 31, 32, and 33. Further, a proximity sensor 53 and a vibrator 54 are connected to the control unit 50. The proximity sensor 53 detects the approach state of the workpiece W and the grinding wheel 4 and supplies the proximity information to the control unit 50. The vibrator 54 is incorporated in the manual feed handles 41 and 42, and the operator's hand can be vibrated by the control unit 50.

Next, the grinding operation of the grinding machine 1 will be described. In addition, in the following description, the case of "displaying on the display device 21, 22, 23" includes display of any one unless otherwise mentioned. In addition, in the case of "input to input keys 31, 32, 33", unless otherwise mentioned, any input is included. In the control unit 50, a control program is programmed in such a manner that an automatic grinding operation and a manual grinding operation can be performed in a mode. To select any mode, enter the input keys 31,32,33. First, the workpiece W is clamped and fixed by the spindle device 7 and the tailstock 8. The control unit 50 detects the position (work position) in the X-axis direction and the Z-axis direction of the workpiece W by a contact (not shown), and is set in the internal memory 58. The position of the grinding wheel in the memory 58 is the position in the X-axis direction and the Z-axis direction of the grinding wheel 4. After that, the control unit 50 displays the grinding wheel position (X-axis direction, Z-axis direction) and the workpiece position (X-axis direction, Z-axis direction) on the display devices 21, 22, and 23.

When the automatic polishing operation is performed, the input keys 31, 32, and 33 in the grinder 1 are used to input information related to the grinding of the workpiece W, and the control program of the control unit 50 creates an NC program for the polishing operation. The control unit 50 rotates the spindle device 7 to rotate the workpiece W according to the NC program. On the other hand, after the grinding wheel 4 is rotated, by controlling the servo motor 61 or the servo motor 62, the grinding wheel 4 automatically grinds the workpiece W. At this time, the servo motors 61 and 62 are rotated by being supplied with pulses from the control unit 50. Each of the servo motors 61 and 62 is determined by the number of pulses transmitted thereto, and its rotation speed is determined by the number of pulses transmitted. The amount of pulsation determines the rotation speed.

Next, during manual grinding operations, the manual feed handles 41 and 42 are in a state where they can be effectively used. The operator rotates one manual feed handle 42 with a right hand, and operates the other manual feed handle 41 with a left hand. When each of the manual feed handles 41 and 42 is rotated, the input portions of the corresponding pulse generators 51 and 52 are rotated in conjunction with it to generate a number of pulses corresponding to the amount of rotation according to the speed of the rotation speed. As long as the manual feed handles 41 and 42 are rapidly rotated, the number of pulses transmitted per hour can be increased. The control unit 50 generates pulses corresponding to these pulses, and transmits them to the drive unit 56 to drive the servo motors 61, 62. The control unit 50 can change the rotation speed of the servo motors 61 and 62 according to the speed mode, and can change the ratio of the pulses transmitted to the drive unit 56 to the pulses generated by the manual feed handles 41 and 42.

Thereby, the servo motors 61 and 62 respectively rotate the angle corresponding to the number of pulses in a direction corresponding to the positive and negative of the supplied pulses at a speed according to the supply speed of the pulses, thereby controlling the relative position movement of the grinding wheel table 6 and the work table 5. . As a result, the grinding wheel 4 approaches and contacts the workpiece W, and the operator confirms the clearance between the grinding wheel 4 and the workpiece W by actually visually inspecting both, and recognizes the sparks and the like caused by the contact between them, and performs the grinding operation.

In this embodiment, the proximity sensor 53 is attached to the grinding wheel table 6. As the proximity sensor 53, a gap sensor, a distance measurement sensor, or the like may be used. In addition, as a notification device for notifying the operator of the approach state, a vibrator 54, a display device 21, 22, 23, and input keys 31, 32, 33 can be used. In addition to the vibrator 54, it is based on a visual notification, and the vibrator 54 is based on a tactile notification. Alternatively, an auditory notification device using a speaker may be used.

In the manual grinding operation of the grinder 1, when the operator rotates the manual feed handles 41 and 42, the relative position of the grinding wheel 4 with respect to the workpiece W is changed. In the grinder 1, as described below, the control unit 50 transmits the pulse interval generated by the pulse generators 51 and 52 to the drive unit 56 according to the approach state of the grinding wheel and the workpiece when the manual feed handles 41 and 42 rotate. The pulse interval is set to be variable so as to control the rotation of the servo motors 61 and 62 to slow down or to suspend the rotation for a period of 1 second to several seconds.

Next, an operation when the grinding wheel 4 is relatively moved in the X-axis direction with respect to the workpiece W by the rotation of the manual feed handle 41 will be described with reference to FIG. 3. FIG. 3 shows the operation flow of the control unit 50, FIG. 3A is a part of the control program, and FIG. 3B is a notification subroutine. In the manual grinding operation, the notification subroutine of FIG. 3B is called by the control program.

When the manual feed handle 41 is rotated to move the grinding wheel 4 in the X-axis direction relative to the workpiece W, the control program of the control unit 50 generates pulses so that one pulse becomes N pulses with respect to one pulse of the pulse generator 51, and Transfer to drive unit 56. In the memory 58 inside the control unit 50, the position of the grinding wheel in the X-axis direction of the grinding wheel 4 is updated and reflected on the display devices 21, 22, and 23 (step S1 in FIG. 3A). This operation is the same as a normal grinder. In the grinder 1 of this embodiment, the control program periodically calls the notification subroutine (step S2 in FIG. 3A).

When the grinding wheel 4 approaches the workpiece W to 1 mm (first approaching state), the control unit 50 detects this in step S11 and then moves to step S12. When the separation is more than 1mm, the control program is returned because it is still not the intended approach state.

In step S12, the vibrator 54 is operated as a notification device for notifying the operator, and the notification is a 1 mm approaching state (first approaching state). It is determined whether or not the proximity is detected by the proximity sensor 53 (step S13). If it is not detected, it will be considered that it is not the state immediately before contact and will return to the control program. When approaching several micrometers to several tens of micrometers, the proximity sensor 53 detects this and outputs a signal. When this signal is detected (specifically, at a signal level equivalent to a distance of 10 micrometers), the control unit 50 determines that the grinding wheel 4 is in a state immediately before contacting the workpiece W (second approach state), and then transfers control Go to step S14.

In step S14, the speed mode in which the rotation of the servo motor 61 is reduced is changed. This change in the feed rate is related to step S1 of the control program. A person who generates pulses such that one pulse with respect to the pulse generator 51 becomes N pulses is set as a person who generates M pulses with respect to one pulse, and returns. Control program. Among them, M is smaller than N. As a result of the speed mode change, after that, the pulse transmitted from the control unit 50 to the drive unit 56 becomes the number of pulses according to the new speed mode, and the approach speed of the grinding wheel 4 and the workpiece W decreases. When the speed mode change is performed, the display devices 21, 22, and 23 are used as a notification device, and the operator is notified that the speed mode change has been performed. Alternatively, the input keys 31, 32, and 33 may be used as a notification device, and a light-emitting element installed inside may be lit or blinked, and the notification may be in a state immediately before contact. After step S14 is completed, the control routine is returned.

In step S14, as shown by the dotted line, step S15 may be performed before or / or instead of the speed mode change. Step S15 is set so that when the proximity sensor 53 detects that it is close to 10 μm, the pulse generator 51 is The pulse generation does not transmit a new pulse toward the drive unit 56. The timer 57 is a timer updated by the operating clock of the control unit 50. In addition, it is prepared in advance that the flag 59 will be referred to before executing step S1 of the control program, and if the flag 59 has been set, the step will end in advance for the pulse generation of the pulse generator 51 without transmitting a new pulse to the drive unit 56. S1. In step S15, the timer 57 and the flag 59 are set in the initial operation, and then the timer 57 is checked, and the state of setting the flag 59 is maintained during a period before a certain time elapses. As a result, during the period set by the timer 57, the control unit 50 does not transmit a pulse to the drive unit 56 during the period set by the timer 57, and the X-axis direction approach operation is temporarily stopped.

According to this embodiment, when the state immediately before the grinding wheel 4 and the workpiece W come into contact, the speed is reduced or paused. By slowing the approaching / contacting speed of the workpiece W and the grinding wheel 4 relative to the rotation speed of the handle 41 before or after the approaching state, or suspending the relative movement of the workpiece W and the grinding wheel 4 when approaching, the grinding wheel 4 can be avoided to maintain A situation where homework cutting occurs when the original speed is cut into the workpiece W. In addition, since the operator is notified of the state immediately before the contact through the display device, the operator can know that there is a case where the speed mode is changed or a case where there is a pause.

In the above embodiment, the embodiment may be modified in such a manner that the pause processing in step S15 is performed together with the speed mode change processing in step S14. In this case, it is possible to prevent the homeopathic cutting from being caused by the operator's slow response, and then reduce the moving speed. On the other hand, even when the pause processing of step S15 is performed in place of the speed mode change processing of step S14, the display device 21, 22, 23 or the input keys 31, 32, and 33 are notified when the pause is performed. This is the case immediately before the contact, so it is still possible to prevent the homeopathic cutting into the grinding due to the slow response of the operator.

Although the operation when the grinding wheel 4 is relatively moved in the X-axis direction with respect to the workpiece W according to the rotation of the manual feed handle 41 has been described with reference to FIG. 3, the grinding wheel 4 is moved relative to the rotation of the manual feed handle 42. The same applies when the workpiece W is relatively moved in the Z-axis direction.

The configuration for moving the grinding wheel in the X-axis direction with respect to the workpiece is not limited to the configuration described in this embodiment, as long as the grinding wheel can be relatively moved in the X-axis direction with respect to the workpiece. Similarly, the configuration for moving the grinding wheel in the Z-axis direction with respect to the workpiece is not limited to the configuration described in this embodiment, as long as the grinding wheel can be relatively moved in the Z-axis direction with respect to the workpiece.

In addition, according to the above embodiment, the operator is notified of the state immediately before the contact before contact, and after the speed is changed or paused, and the grinding wheel is actually in contact with the workpiece, as shown in Patent Document 3, For authenticity, a brake (for example, a magnetic powder brake) provided in the handle unit may be used to manually increase the rotational resistance during the handle operation, and the condition of maintaining the contact state between the grinding wheel and the workpiece may be fed back to the operator with a sense of force.

In addition, in the above-mentioned embodiment, although the operator was notified of the state immediately before the contact in the state immediately before the contact, the position of the grinding wheel and the workpiece in the memory 58 can also be used to approach 1 mm. At the time of the state, the display device 21, 22, and 23 are used to notify the approaching state, and at the same time, the speed mode is changed or suspended. In this case, the proximity sensor 53 compares the position of the grinding wheel in the memory 58 with the position of the workpiece, and is implemented by a program as shown in step S11 of FIG. 3B to detect the proximity state. According to this configuration, since the speed mode is changed or suspended at a much higher place before the actual contact, the workability is worse than that in the case of 10 micrometers. In addition, the current situation is a grinding machine with high processing accuracy and several micrometers.

In the above embodiment, when it is determined that the grinding wheel 4 is in a state immediately before contacting the workpiece W (second approaching state), the display devices 21, 22, and 23 are used as a notification device to notify that the speed mode change has been performed. operator. Alternatively, the input keys 31, 32, and 33 may be used as a notification device to light or blink the light-emitting element mounted inside, but a vibrator different from the vibrator 54 may be used in combination with the display device 21, 22 23, at least one of the light-emitting element, the vibrator, or two of them, or a combination of all three, to notify the operator of the change in speed mode.

Claims (3)

    A grinding machine is characterized by comprising: a grinding wheel that grinds a workpiece; a nozzle that sprays coolant on the workpiece; a manual feed handle that is operated by an operator's rotation; and a proximity sensor that detects the approaching state of the workpiece to the grinding wheel; A moving device that moves a workpiece and a grinding wheel to change the relative position of the two; a control unit that controls the moving device so that the workpiece and the grinding wheel approach / contact the workpiece and the wheel at a speed according to the rotation speed of the manual feed handle; and a notification device , Which notifies the operator, and the control unit responds to the detection information of the proximity sensor, and uses the notification device to notify the operator of the approaching state, and at the same time, it will feed relative to the manual feed before and after the approaching state. The rotation speed of the handle slows the approaching speed of the workpiece to the grinding wheel, or suspends the relative movement of the workpiece and the grinding wheel when approaching.         For example, the grinder of claim 1, wherein the above-mentioned control unit is used when the workpiece and the grinding wheel are close to the first approaching state, and the operator is notified of the first approaching state by using the above notification device, and the approaching state is closer than the first approaching state. When the second approaching state is approached, the second approaching state will be notified, and the speed of the workpiece approaching the grinding wheel will be slowed relative to the rotation speed of the manual feed handle, or the workpiece and the wheel will be suspended during the approaching state. Relative movement.         The grinder of claim 1, wherein the notification device is at least one or a combination of two or more of a display device, a light emitting element, and a vibrator.