JPS5834253B2 - Kensaku Kakousouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a grinding device for machining a workpiece into a predetermined shape by a wire grinding tool stretched between a pair of support devices, and particularly to When a grinding tool is given a rotational movement centered at least on the axis of the wire and a workpiece is ground by the grinding action of the rotational movement, a difference in rotational speed at both ends of the wire grinding tool causes a linear This relates to something that prevents twisting from occurring in the state.

In conventional machining with a band saw, the direction of the cutting edge must always be directed in the direction of machining progress, making it difficult to process irregular shapes. By using a linear wire grinding tool with a cutting edge, giving the wire grinding tool rotational motion around the axis, and also reciprocating motion in the axial direction, it is easy to process irregular shapes. The present inventor has already proposed a grinding device that is capable of doing this.

In this case, since rotation is applied to the wire grinding tool, which has cutting edges all around its circumference, even if the cutting direction changes due to machining feed, the machinability does not change accordingly, and it is always kept at the specified level. It is possible to perform machining with a cutting performance of

However, when drive sources that apply rotational force to both ends of a wire grinding tool are provided separately, it is difficult to apply the same rotational speed to both ends in synchronization.
When a difference in rotational speed occurs, the wire grinding tool is twisted, which increases grinding resistance and reduces grinding performance, or changes the width of the kerf and reduces machining accuracy. Problems arise such as abrasive grains attached to the wire grinding tool peeling off and falling off.

Furthermore, since the grindability of wire grinding tools is affected by the tension state, it is desirable to increase the tension, but when applying high tension, rotation unevenness may occur at both ends due to the difference in rotational speed as described above. If this happens, there is a risk of cutting, and on the other hand, if grinding is performed with a low tension to absorb twisting due to uneven rotation, there is a disadvantage that processing accuracy will be reduced.

In view of the above-mentioned points, the present invention is proposed for the purpose of imparting rotational motion at the same rotational speed in synchronization to both ends of a wire grinding tool, and by fixing abrasive grains to the peripheral surface. A device for grinding a workpiece by facing a wire grinding tool from a direction perpendicular to the tool axis, the apparatus comprising: a U-shaped frame; and tightening fixing parts at both ends of the wire grinding tool. Each support device for the tool is rotatably provided at both ends of the frame and facing each other, a drive motor is provided on the frame, and the drive motor is connected to a rotational output shaft of the motor to rotate the rotational output shaft. a periodic rotation transmission mechanism that transmits motion to each of the support devices as synchronized rotations in the same direction and at the same speed; and a holding device that holds the frame to bring the tool into grinding contact with the workpiece attachment device. The mounting device is characterized by comprising a processing feed device that relatively feeds the mounting device and the holding device in a direction in which the tool and the workpiece are opposed to each other.

Next, the present invention will be specifically explained based on the drawings.

FIG. 1 is a sectional view showing an apparatus according to an embodiment of the present invention,
Reference numeral 1 denotes a U-shaped frame, which is attached to a suitable fixed base 2.

In addition, when mounted on the pedestal, the workpiece attached to the mounting device is fed into a predetermined machining shape, and the frame 1 is connected to the head of a milling machine using the mounting seat 3. A predetermined operation may be performed.

4 is a drive motor fixedly provided at the center of the base of the frame 1, and coaxial upper and lower rotation output shafts 5,
5' extends, and a drive pulley 6 and a pulley are fixed to both ends of these, respectively, and a bearing 7 provided on the frame 1
．． It is pivotally supported by γ.

On the other hand, support devices 10° 10' are rotatably attached to the support parts 8, 8' at both upper and lower ends of the frame 1 via screw-type adjustment rings 9, 9' by bearings 11.11' and 12.12'. supported.

Driven pulleys 13, 13' are integrally provided at the outer end of the support device 10, 10', and between the driven pulleys 13, 13' and the driving boos IJ 6, 6'. A belt 14°14' is stretched.

In this embodiment, instead of the drive pulley 6゜6' and the driven boots IJ 13, 13', a sprocket gear may be provided below and a chain wheel may be stretched between them. You may also use it.

The inner ends of the support devices 10, 10' are formed into collet chucks, and the wire grinding tool 15 is clamped and fixed by tightening with screw nuts 16, 1e'.

17, 17' are handles for rotating the screw type adjustment ring 92g via grooves in the support portion 8° 8' of the frame 1, and by moving the screw type adjustment ring 9, 9' up and down, the support device is adjusted. A predetermined tension is applied to the wire grinding tool 15 by adjusting the distance between 10 and 10'.

In this case, since bearings 12, 12' are interposed between the screw type adjustment rings 9, 9' and the support devices 10, 1σ, the wire grinding tool 15 is not twisted by the rotation of the rings 9, 9'. Although there is little risk of twisting occurring when setting a high tension, the rings 9 and
Preferably, one has a counter-threaded configuration with respect to the other, so that the spacing between the support devices 10 and 10' can be adjusted by rotation in the same direction.

In the above configuration, for example, when the workpiece is fixed to the mounting device, the mounting seat 3 is set to the head of the milling machine, and the drive motor 4 is operated, the workpiece is fixedly supported by the rotation output shafts 5, 5'. By rotating the driving boobies IJ 6 , 6', the driven boobies IJ 13 ,
13' rotates.

Therefore, the support device 10.10' rotates synchronously and in the same direction and at the same rotational speed, and the wire grinding tool 15 rotates at high speed about its axis without twisting, and the head of the milling machine and the table are rotated at high speed. According to the relative movement by copying or NC control, the workpiece (not shown) is cut, cut out, or its peripheral edge is ground and formed.

Therefore, when machining is actually performed by pressing the wire grinding tool 15 against the workpiece by machining feed, a biased load will be applied to each support device 10° 10' depending on the placement position of the workpiece. , the workpiece is supported by a pair of support devices 1
It is preferable to arrange the wire grinding tool 15 so that it is in contact with the wire grinding tool 15 at approximately the center between 0 and 1σ. Slip occurs on the support device 10.
10', there is no rotational unevenness, so the pressure contact force (cutting resistance) is below the limit load at which the slip occurs.
If the workpiece is machined by the support devices 10 and 10', it is not necessarily necessary to arrange the workpiece in the center between the support devices 10 and 10'.

Furthermore, even if the load is not biased, if a high load is applied to both ends of the wire grinding tool 15, the slip will occur and uneven rotation will occur in each support device 10, 1σ. Even when machining is performed by placing the support device 10 in the center between the belts 14 and 10', it goes without saying that the machining must be performed with a cutting force that is less than the limit load for causing slip. teche7
Needless to say, in the case of a configuration using a timing belt or a timing belt, the above-mentioned slip does not occur.

Next, the embodiment device shown in FIG. 2 is the same as the embodiment device shown in FIG. The link 18 is connected to a rotating crank 19 by an appropriate means, and the frame 1 is moved up and down with respect to the pedestal 2 as shown by the arrow via a bearing, etc., so that the wire grinding tool 15 is reciprocated in the axial direction. It is designed to add a jig saw grinding action, and the drive pulley is 6゜6',
In addition to the rotational grinding action as shown by the arrow of the wire grinding tool 15 via the belt 14, 14', the driven pulleys 13, 13', and the supporting devices 10, 10', a reciprocating grinding action by the reciprocating movement of the tool 15 in the axial direction is added, Constructed to provide more effective grinding action.

In the present invention, the reciprocating motion and reciprocating grinding action of the wire grinding tool refer to a motion and mode of action in which a workpiece is ground in a so-called jig saw style by reciprocating motion in the axial direction of the tool, and will be described later. This type of vibration is different from the tool vibration caused by an ultrasonic vibration device.

In this case, since the wire grinding tool 15 performs vertical grinding work on the workpiece 20 while performing rotational grinding work, the wire grinding tool 15 is biased in the axial direction due to this vertical reciprocating movement. Although it will be a burden,
In the same manner as described for the embodiment shown in FIG. 1, if machining is performed with a cutting force below the limit load at which slip occurs, the support devices 10, 10' will rotate unevenly and the wire grinding tool will be twisted. There is no risk that this will occur.

In this way, even when reciprocating grinding action is added, stable machining can be performed without twisting the wire grinding tool, but in the embodiment apparatus shown in FIG.
The structure is such that the slip does not occur even when machining is performed under a condition where a biased high load is applied due to reciprocating motion.

That is, the tension pulleys 21, 21' rotatably supported by the support shaft 22 are brought into contact with the belts 14, 14', and the pin 23 is fixed to the center of the support shaft 22 and protrudes through the frame. A pinion 24 is fixedly provided at the tip of the pinion 24, and a rack 25 that engages with the pinion 24 is fixedly arranged on the base 2 on the fixed side.

When the frame 1 moves up and down via the non-crank 18 due to the rotation of the crank 19, the pinion 24, which performs up and down reciprocating motion together with the frame 1, moves to the fixed rack 25.
Since it is engaged with the reciprocating movement, it rotates in synchronization with the reciprocating movement, and the rotating direction is tailings, and this repeated reversal rotation of the pinion 24 causes the support shaft 22 to rotate around the fixed point of the pin 23. The tension pulley 21.2, which is pivoted at both ends of the support shaft 22, undergoes repeated inversion rotation (pendulum motion) along with the pinion 24 in the front and back directions in the drawing.
The pressure force of the belt 14.1' on the belt 14.14' changes in strength in synchronization with the reciprocating movement, and accordingly, the pressure of the belt 14.1' on the belt 14.14' changes in strength.
The tension at 14' will also be increased synchronously and periodically.

Therefore, for example, when a grinding operation is performed while the wire grinding tool 15 moves upward due to the upward movement of the frame 1, the tension in the portion of the tool 15 located above the workpiece 20 is reduced due to cutting resistance. When the frame 1 moves downward, a biased high load will be applied to the lower support device 1σ. Therefore, the contact positional relationship between the tension pulleys 21° 21' and the belts 14 and 14' is adjusted such that the tension of the belt 14 is increased by increasing the pressure of the tension pulleys 21 against the belt 14 when the tool 15 moves upward. The axis of the tool 15 is increased by increasing the tension of the belt 14' by increasing the pressing force of the tension pulley 21' against the belt 14' when the tool 15 moves downward. It is possible to prevent the slip caused by the bias load associated with the reciprocating movement in the direction, and to perform stable and accurate machining without twisting the wire grinding tool.

The embodiment shown in FIG. 3 has an ultrasonic vibration device 26 installed on one side of the support device 10, 10' in the embodiment shown in FIG. is added to enable efficient grinding work to be performed, and in this case as well, by performing machining with a cutting force below the limit load at which slip occurs, twisting is not caused in the wire grinding tool. It is possible to perform stable machining without any problems.

As described above, the apparatus of the embodiment shown in FIG. 3 performs grinding by the rotary grinding action and the vibration grinding action of the tool 15. If additionally provided, processing can be performed simultaneously by each grinding action of rotary grinding action, reciprocating grinding action, and vibration grinding action.

As described above, according to the present invention, rotational motion at the same rotational speed can be applied to both ends of a wire grinding tool in synchronization with a simple configuration, and twisting of the wire grinding tool can be avoided. Therefore, there is no risk of breakage even when the wire grinding tool is set to a high tension state, and highly accurate machining can be performed with a constant machining groove width. Stable machining can be carried out continuously with a predetermined machining performance without the grinding resistance increasing and the grinding performance decreasing, or the attached abrasive grains peeling off and falling off.

Incidentally, the wire grinding tool may be one in which two wires are bent over and abrasive grains are attached as shown in Fig. 4a, or a fourth
It is sufficient to have three wires wrapped around each other as shown in figure b.

The abrasive grains can not only be attached using an adhesive or the like, but also may be fixed by electroplating or chemical plating so that a part of the abrasive grains is buried in the plating layer.

[Brief explanation of the drawing]

1, 2, and 3 are sectional views showing an embodiment of the present invention, and FIGS. 4a and 4b are explanatory views of the wire grinding tool. 1...U-shaped frame, 2...Fixed pedestal, 3...Mounting seat, 4...Drive motor, 6, 6'... ...Drive pulley, 10,1σ...
... Support device, 13, 13'... Driven pulley, 14, 14'... Belt, 15...
...Wire grinding knee Jl, 18...Link, 19...Crank, 20...Workpiece, 21, 21'...Tension pulley, 2
2...Spindle, 23...Pin, 24...
...Pinion, 25...Rack, 26...
...Ultrasonic vibration device.

Claims (1)

[Scope of Claims] 1. In an apparatus for grinding a workpiece by facing a wire grinding tool having abrasive grains fixed to the peripheral surface from a direction perpendicular to the tool axis direction, a U-shaped frame is provided. and a support device for the tool, which has tightening fixing parts at both ends of the wire grinding tool, and is rotatably provided at both ends of the frame and facing each other, and one drive provided on the frame. a synchronous rotation transmission mechanism that transmits the rotational motion of the output shaft of the one drive motor to each of the rotational axes so that the motor and each of the rotational axes of each of the support devices are rotated synchronously in the same direction and at the same speed; , a holding device that holds the frame so as to bring the tool into grinding contact with a mounting device for the workpiece, and a holding device that holds the frame in a manner such that the mounting device and the holding device are relative to each other in a direction in which the tool and the workpiece come into contact with each other. A grinding device characterized by comprising a processing feed device for processing feed. 2. In an apparatus for grinding a workpiece by bringing a workpiece into contact with a wire grinding tool having abrasive grains fixed to the peripheral surface from a direction perpendicular to the tool axis direction, the wire grinding tool comprises a U-shaped frame and the wire grinding tool. each support device for the tool, which has a tightening fixing portion at each end thereof and is rotatably provided at both ends of the frame and facing each other; one drive motor provided on the frame; a synchronous rotation transmission mechanism that transmits the rotational motion of the output shaft of the one drive motor to each of the rotating wheels so that each of the rotating shafts of the supporting device rotates in synchronization in the same direction and at the same speed; a reciprocating motion device for relatively reciprocating a fixedly supported wire grinding tool and the workpiece in the axial direction of the tool; and a frame for bringing the tool into grinding contact with a mounting device for the workpiece. A grinding process characterized by comprising: a holding device that holds the mounting device and the holding device; and a processing feed device that relatively feeds the mounting device and the holding device in a direction in which the tool and the workpiece are opposed to each other. Device.