JP3903416B2 - Cutting blade polishing method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cutting blade polishing method and apparatus, and more particularly, to a cutting blade polishing method and apparatus for polishing, for example, a cutting blade for cutting a thin sheet-like object to be cut with a rotating grindstone. .
[0002]
[Prior art]
2. Description of the Related Art A magnetic tape cutting device that cuts a wide magnetic tape raw material into a generally used narrow magnetic tape is known. In such a cutting device, for example, as shown in FIG. A plurality of upper round blades 3 and lower round blades 4 are arranged in the axial direction on the shaft 1 and the lower round blade shaft 2, respectively, and mounted so that their blade tips are positioned at predetermined intervals, and the upper round blades facing each other. 3 and the lower round blade 4 are disposed so that the vicinity of the blade edge overlaps in the radial direction, and the upper round blade 3 and the lower round blade 4 are rotated through the upper round blade shaft 1 and the lower round blade shaft 2. A wide magnetic tape 5 between the circular blades 3 and 4 is transferred in a direction perpendicular to the paper surface of FIG. 13 with the magnetic layer facing upward, and this magnetic tape 5 is cut into a plurality of strips. is doing.
[0003]
The cross-sectional shape of the cutting edge 4a of the lower round blade 4 including the rotation axis of the lower round blade 4 is formed in a substantially right angle, but the substantially right angle is chamfered. The sharpness of cutting the magnetic tape by chamfering is improved, and the occurrence of unnecessary convex portions and burrs in the cut surface of the magnetic tape is suppressed.
[0004]
The chamfering is performed by moving a grinding wheel fixed on a spindle shaft rotated by a motor together with the motor and spindle, and pressing the grinding wheel against the cutting edge of the lower round blade. .
[0005]
[Problems to be solved by the invention]
Recently, in order to increase the recording density of magnetic tape, the thickness of the magnetic tape is reduced by using PEN or aramid resin as a base material in order to extend the length of the magnetic tape accommodated in a cassette or the like. As a result, unnecessary protrusions and burrs are likely to occur in the cut surface of the magnetic tape. In addition, the width of the recording track is narrowed to increase the recording density of the magnetic tape, and in order to accurately record a signal on this narrow recording track or to read the signal accurately, it is necessary to run during recording / reproduction. It is necessary to accurately position the magnetic tape in the width direction, so that the interval between the guides for restricting the tape running position is narrowed, and the contact pressure between the guide and the side surface of the magnetic tape is increased. The burr is shaved by the guide and is easy to fall off. And, when unnecessary convex parts and burrs are scraped while the magnetic tape is running, the shavings are attached to the magnetic surface side of the magnetic tape and pass through the recording head or the reproducing head to cause dropout. It causes various troubles. Therefore, in the case of a magnetic tape having increased recording density in recent years, there is a demand for further improving the quality of the cut surface so that unnecessary convex portions and burrs are not generated on the cut surface of the magnetic tape.
[0006]
As a result of various investigations regarding the quality improvement of the magnetic tape cut section in response to the above request, chamfering was performed with high accuracy over the entire circumference of the substantially perpendicular corner of the cutting edge of the lower round blade, for example ± 0. When cutting thin magnetic tapes using a lower round blade with a chamfer of a predetermined shape on the cutting edge with an accuracy of 5 μm, the occurrence of unnecessary protrusions and burrs on the cut surface of these magnetic tapes is suppressed. As a result, it was found that a cut surface with higher quality can be obtained.
[0007]
However, in the conventional chamfering method described above, the grindstone for polishing the lower round blade is moved integrally with the motor and the spindle as described above, so the weight of the mechanism moved together with the grindstone is heavy and the amount of polishing is high. Control that moves the grindstone following the surface runout when the runout (surface runout) in the rotation axis direction of the lower round blade of about several μm occurs, especially when grinding is difficult. As a result, it is difficult to control the side pressure when polishing the lower round blade with high accuracy, and as a result, the area where the grinding wheel hits the cutting edge is strong and weak, or the area where the grinding wheel hits the cutting edge and the area where the grinding wheel does not hit May occur. Also, there is a possibility that the grinding characteristics of the grinding wheel may change due to clogging of the grinding stone or dropping of abrasive grains, so it is difficult to chamfer a predetermined shape uniformly and with high precision on the entire circumference of the lower round blade. There's a problem.
[0008]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cutting blade polishing method and apparatus capable of polishing a cutting blade into a desired shape with high accuracy.
[0009]
[Means for Solving the Problems]
The first cutting blade polishing method of the present invention is a cutting blade polishing method in which the cutting blade is polished by a rotating rotating grindstone body, and the rotating grindstone body is supported so as to be movable in the rotation axis direction of the rotating grindstone body. Then, the blade is pressed against the cutting blade while being urged toward the cutting blade, and the cutting blade is polished.
[0010]
The second cutting blade polishing method of the present invention is a cutting blade polishing method in which the cutting blade is polished by a rotating rotating grindstone body, wherein the rotating grindstone body is used as the cutting blade in the rotational axis direction of the rotating grindstone body. The cutting blade is polished by being pressed while being elastically deformed or elastically displaced.
[0011]
A polishing apparatus for a cutting blade according to a first aspect of the present invention is a polishing apparatus for a cutting blade comprising a rotating grindstone body and a rotating means for supporting and rotating the rotating grindstone body. It is supported by the rotating means so as to be movable in the direction of the rotation axis of the means, and further comprises an urging means for urging the rotating grindstone body toward the cutting blade in the direction of the rotating axis. It is.
[0012]
A polishing apparatus for a second cutting blade according to the present invention is a polishing apparatus for a cutting blade comprising a rotating grindstone body and a rotating means for rotating the rotating grindstone body, wherein the rotating grindstone body is rotated when the rotating means is rotated. It has the ring-shaped grindstone part which can be elastically deformed or elastically displaced in the rotating shaft direction.
[0013]
Note that “movable in the direction of the rotation axis” means that it can move in a direction including a component in the direction of the rotation axis.
[0014]
Further, elastic deformation in the direction of the rotation axis means elastic deformation in a direction including a component in the axial direction of rotation. In addition, the elastic deformation means a deformation that generates a force to return the deformation to at least when it is deformed at least during rotation of the rotating grindstone body, and is configured by combining a plurality of parts. The elastic deformation includes a deformation in a case where a force for returning the deformation is generated when the formed material is deformed.
[0015]
Further, the elastic displacement in the direction of the rotation axis means that the elastic displacement is performed in a direction including a component in the axial direction of rotation. The elastic displacement refers to the displacement when the grindstone portion is displaced at least during rotation of the rotating grindstone body in a configuration in which the portion supporting the grindstone portion can be deformed without deforming the grindstone portion itself. It means a displacement that generates a force to return to In addition, the part which supports the said grindstone part does not necessarily need to be elastically deformable, and should just be deformable.
[0016]
【The invention's effect】
According to the first cutting blade polishing method and apparatus of the present invention, the rotary grindstone body is supported so as to be movable in the direction of the rotation axis and is pressed against the cutting blade while being urged toward the cutting blade for polishing. Since the rotating grindstone body having a small mass is urged and pressed against the cutting blade, the relative position error between the polishing apparatus on which the rotating grindstone body is arranged and the cutting blade, for example, positioning error or surface runout error (surface Even if the amount of run-out occurs, the rotating grindstone itself with a small mass follows the cutting blade by the urging force and is pressed against the cutting blade with a constant side pressure to polish the cutting blade under more constant polishing conditions. Therefore, the cutting blade can be polished to a desired shape with high accuracy.
[0017]
According to the first cutting blade polishing method and apparatus of the present invention, the rotating grindstone body is pressed against the cutting blade while being elastically deformed in the axial direction of rotation and polished, and the elastic deformation of the rotating grindstone body having a small mass is performed. The rotating grindstone is pressed against the cutting blade by the reaction force of this and the rotational force in the direction of the rotation axis when the rotating grindstone is rotated. Even if a relative position error of, for example, positioning error or surface runout error (surface runout amount) occurs, the elastically deformed or elastically displaced portion in the rotating grindstone body follows the cutting blade with a restoring force and remains constant. Since the cutting blade is pressed against the cutting blade by the side pressure and can be polished under more constant polishing conditions, the cutting blade can be polished to a desired shape with high accuracy.
[0018]
In the first and second cutting blade polishing methods and apparatuses described above, a number of cutting blades arranged adjacent to each other, such as cutting blades incorporated in the lower round blade unit of the magnetic tape cutting apparatus, are used. When polishing is performed, positioning errors are accumulated as the polishing apparatus is sequentially positioned with respect to each cutting blade, and the positioning error of the polishing apparatus with respect to the cutting blade may increase as the cutting blade is polished later. Since the rotating grindstone body itself or the elastically deformed or elastically displaced portion of the grindstone including the accumulated positioning error of the polishing apparatus follows the surface to be polished of the cutting blade, the same as above In addition, each cutting blade can be polished to a desired shape with high accuracy, and a remarkable effect by applying the present invention can be expected.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing a schematic configuration of a first embodiment in which a cutting blade polishing apparatus of the present invention is applied to a round blade unit polishing apparatus for polishing a cutting blade of a lower round blade unit of the magnetic tape cutting apparatus described above. FIG. 2 is a side view of the round blade unit polishing apparatus, FIG. 3 is an enlarged front view of a part of the round blade unit polishing apparatus, and FIG. 4 shows a rotating grindstone body when the round blade is polished. FIG. 5 is a diagram showing details of the C value and the H value, and FIGS. 6 to 9 are diagrams for explaining the results of experiments using the round blade unit polishing apparatus.
[0020]
The round blade unit polishing apparatus according to the first embodiment of the present invention includes a polishing apparatus main body 100, a polishing apparatus transfer means 110 for transferring and positioning the polishing apparatus main body 100 in the vertical direction of the arrow X in the figure, A round blade for chucking and rotating a round blade unit 130 formed by arranging a large number of round blades, which are thin cutting blades, arranged in the direction of the rotation axis, and for transferring and positioning the round blade unit 130 in the horizontal direction Y in the figure. And a rotary transfer means 120.
[0021]
The polishing apparatus transfer means 110 and the round blade rotation transfer means 120 are disposed on a common base 140, and the polishing apparatus transfer means 110 is a transfer support that supports the polishing apparatus main body 100 as shown in FIG. 81, a linear guide that is connected to the transfer support 81 and moves the transfer support 81 in the direction of the arrow X in the vertical direction, and a vertical transfer mechanism 80 using a ball screw or the like, and driving the vertical transfer mechanism 80 Thus, the polishing apparatus main body 100 is transferred in the arrow X direction via the transfer support 81.
[0022]
The round blade rotation transfer means 120 includes a chucking base 127 that is transferred in the left-right direction in the direction of arrow Y in FIG. 1, and a first support 125 and a second support 126 that are disposed on the chucking base 127. The center shaft 121 and the rotation drive shaft 122 that are respectively disposed on the first support column 125 and the second support column 126 to chuck the round blade unit 130, the rotation drive unit 124 that rotates the rotation drive shaft 122, and the linear guide And a left and right transfer mechanism 123 that transfers the chucking base 127 in the arrow Y direction by a mechanism using a hydraulic cylinder or the like. This round blade rotation transfer means 120 transfers the round blade unit 130 chucked between the center shaft 121 and the rotation drive shaft 122 in the arrow Y direction via the chucking base 127 by driving the left and right transfer mechanism 123. At the same time, the round blade unit 130 is rotated via the rotation drive shaft 122 by the rotation drive unit 124.
[0023]
The polishing apparatus main body 100 includes a rotating grindstone body 10, a grindstone rotating means 20 that is a rotating means that supports and rotates the rotating grindstone body 10, an urging means 30 that urges the rotating grindstone body 10 in the rotation axis direction, And a connection arm 40.
[0024]
The grindstone rotating means 20 is fitted to a rotating spindle unit 21 for transmitting a rotating force for rotating the rotating grindstone body 10, and a spindle shaft 22 of the rotating spindle unit 21 so as to rotate integrally with the spindle shaft. A spindle holder 24 for supporting the body 10 and a polishing motor 26 for rotating the spindle shaft 22 via a belt 25 hung on a pulley fixed to the spindle shaft 22, the rotating spindle unit 21. The polishing motor 26 is connected to and integrated with the connection arm 40. The spindle holder 24 fitted to the spindle shaft 22 is fixed to the spindle shaft 22 with screws 23 (see FIG. 3).
[0025]
The connecting arm 40 supports the grindstone rotating means 20 and is connected to the transfer support 81 so that the angle of the grindstone rotating means 20 can be adjusted on the XY plane in FIG.
[0026]
As shown in FIG. 3, the rotating grindstone body 10 is formed on the outer periphery of the side surface of the grindstone base plate 11 having a highly rigid disc-shaped grindstone base plate 11 having an opening that fits into the fitting portion 27 of the spindle holder 24. It consists of the formed grindstone tip part 12. The rotating grindstone body 10 is fitted to the fitting portion 27 of the spindle holder 24 so that the grindstone tip portion 12 side faces a flange portion 28 described later, and is supported so as to be movable in the direction of the rotation axis of the spindle shaft 22. In the rotating grindstone body 10, a detent pin 13 fixed to a flange pin hole 29 formed in the flange portion 28 at the tip of the spindle holder 24 is inserted into the grindstone pin hole 14 of the grindstone base plate 11. The rotational force of the spindle shaft 22 is transmitted to the rotating grindstone body 10 through the stop pin 13. Two flange pin holes and two non-rotating pins fixed to the hole are arranged at positions corresponding to the rotation axis so as not to lose the balance at the time of rotation. It is arranged according to the position of the detent pin. With the above configuration, the rotating grindstone body 10 is supported by the grindstone rotating means 22 so as to be movable in the direction of the rotation axis of the grindstone rotating means 20.
[0027]
The urging means 30 is formed by rolling a threaded portion 31 screwed into a threaded portion 42 of the spindle holder 24, a spring receiving disk 33 having a tapered surface T contacting a ring spring 32 described later, and a coil spring rounded into a ring shape. A ring spring 32 having a ring diameter that can be expanded and contracted. The threaded portion 31 of the spring receiving disk 33 is screwed to the threaded portion 42 of the spindle holder 24 in a state where the ring spring 32 is disposed between the tapered surface T of the spring receiving disk 33 and the rotating grindstone body 10. And the spring receiving disk 33 are integrated.
[0028]
The ring spring 32 moves along the tapered surface T while reducing its diameter by its contraction force, and urges the rotating grindstone body 10 toward the flange portion 28 (rightward in FIG. 3, arrow V direction). Thereby, the urging means 30 urges the rotating grindstone body 10 toward the round blade of the round blade unit 130 in the direction of the rotation axis.
[0029]
Next, the operation in the above embodiment will be described.
[0030]
After the round blade unit 130 is chucked by being sandwiched between the center shaft 121 provided on the first support 125 of the round blade rotation transfer means 120 and the rotation drive shaft 122 provided on the second support 126. The round blade unit 130 is transferred in the direction of arrow Y in the figure by the left and right transfer mechanism 123, and is positioned at the initial setting position where the first round blade 131 is polished. The round blade unit 130 positioned at the initial setting position is rotated by the rotational driving force transmitted from the rotational driving unit 124 via the rotational driving shaft 122.
[0031]
The polishing apparatus main body 100 is connected to the vertical transfer base 81 of the polishing apparatus transfer means 110 so that the rotation axis L1 of the spindle shaft 22 is inclined at a predetermined angle α with respect to the rotation axis L2 of the round blade unit 130. Then, it is moved downward along the X direction in the drawing so as to approach the round blade unit 130 by the vertical transfer mechanism 80 and stopped at a predetermined position (height). At this time, the polishing apparatus main body 100 is stopped so that the grindstone tip 12 is positioned between the two round blades (between the first round blade 131 and the second round blade 132) as shown in FIG. The
[0032]
Next, the rotary grinding wheel 10 is rotated via the spindle shaft 22 by driving the polishing motor 26, and the round blade is rotated and transferred while observing the cutting edge of the grinding stone tip portion 12 and the first round blade 131 with a tool microscope (not shown). The first polishing start position where the position of the round blade unit 130 is adjusted by the control of the means 120 (left / right transfer mechanism 123), and the distance between the grindstone tip portion 12 and the cutting edge Q1 of the first round blade 131 is a predetermined distance. The round blade unit 130 is positioned in the position. In the drawing, when the first round blade 131 is positioned at the first polishing start position, the first round blade 131 of the round blade unit 130 approaches the rotating grindstone 10 by the round blade rotation transfer means 120. It is sent to the left (in the direction of arrow W) by a predetermined distance, the cutting edge Q1 of the first round blade 131 and the grindstone tip portion 12 come into contact with each other, and the cutting edge of the first round blade 131 is polished by the rotating grindstone body 10. Is done.
[0033]
When the polishing of the first round blade 131 is completed, the polishing apparatus main body 100 is transferred upward along the X direction by the polishing apparatus transfer means 110, and then the round blade unit 130 is indicated by the arrow in the figure by the rotary blade rotation transfer means 120. When transported by a distance corresponding to one round blade in the V direction, the polishing apparatus main body 100 is again moved downward by the polishing apparatus transfer means 110 and stopped at a predetermined position (height). Thereby, the grindstone tip part 12 is positioned between the second round blade 132 and the third round blade 133, and this position is a second polishing start position for polishing the cutting edge of the second round blade 132. Become.
[0034]
Next, the second rotary blade 131 of the round blade unit 130 is fed by a predetermined distance in a direction (arrow W direction in the figure) approaching the grindstone tip portion 12 by the round blade rotation transfer means 120, and the round blade unit 130. The cutting edge Q2 of the second round blade 132 and the grindstone tip portion 12 come into contact with each other, and the cutting edge of the second round blade 132 is polished.
[0035]
By repeating the above operation, all the blade tips of the round blade unit 130 are polished, and the polishing of the round blade unit 130 by the round blade unit polishing apparatus is completed. This operation is repeated by automatic cycle control.
[0036]
Here, the detail of grinding | polishing of the blade edge | tip of the round blade by the rotary grindstone body 10 is demonstrated.
[0037]
When the polishing apparatus main body 100 is positioned at the first polishing start position, the predetermined distance between the grindstone tip portion 12 and the cutting edge Q1 of the first round blade 131 is 0.2 mm. When the round blade 131 is moved by a predetermined distance of 0.4 mm from the start position in a direction in which the round blade 131 approaches the grindstone tip portion 12 (in the direction of arrow W in the figure), the grindstone tip portion 12 contacts the cutting edge of the first round blade 131. After that, the first round blade 131 is further pushed out by a predetermined distance (predetermined polishing amount), and the rotation located at the initial position J (indicated by a two-dot chain line) of the rotating grindstone 10 shown in FIG. The grindstone body 10 is moved about 0.2 mm (0.4 mm-0.2 mm) toward the biasing means 30 (in the direction of arrow W in the figure) and moved to the position J ′. At this time, as the ring spring 32 moves along the tapered surface T of the spring receiving disk 33 toward the spring receiving disk 33 (in the direction of arrow W in the figure), the diameter of the ring spring 32 increases, whereby the rotating grindstone 10. Absorbs the amount of movement equivalent to the amount of polishing. Then, polishing is performed in a state where the rotating grindstone 10 receives a biasing force in the direction of arrow V by the contraction force of the ring spring 32. Since the polishing is performed in such a state, even if the first round blade 131 is shaken in the rotation axis direction, the grindstone tip portion 12 having a small mass is urged by the ring spring 32 so that the edge of the first round blade 131 is cut. The first round blade 131 can be polished with a substantially constant side pressure without following the vibration of the blade and leaving the blade edge. Further, after the first round blade 131 comes into contact with the grindstone tip portion 12, an error is caused in the amount of polishing approach, which is a distance for moving the grindstone tip portion 12 (the rotating grindstone body 10) by moving further in the arrow W direction in the figure. Even if it exists, since the fluctuation | variation of the force (namely, side pressure) which energizes the rotary grindstone body 10 is small, the cutting edge of a round blade can be grind | polished on substantially constant grinding | polishing conditions, and by managing grinding | polishing time The polishing amount can be accurately controlled.
[0038]
That is, as shown in FIG. 5, the cross-sectional shape of the polished first round blade 131 cut along a plane passing through the rotation axis of the round blade unit 130 is parallel to the rotation axis L2 of the round blade unit 130. C value (tape chamfering length in the tape surface direction) at side E corresponding to the outer peripheral surface of the round blade and chamfering at side F corresponding to the side surface of the round blade substantially perpendicular to the rotation axis When expressed by the H value (the chamfering length in the cutting direction) which is the length, the inclination angle θ expressed by the C value and the H value (where C value <H value) is the rotation of the round blade unit 130. The inclination angle α of the rotation axis L1 of the spindle shaft 22 with respect to the axis L2 is substantially equal, and the C value can be controlled with an accuracy of ± 0.5 μm by managing the polishing time.
[0039]
In addition, since the rotary grindstone body 10 is movably fitted to the fitting portion 27 of the spindle holder 24 and there is a clearance between the rotary grindstone body 10 and the round blade comes into contact with the rotary grindstone body 10, it is further illustrated in the drawing. By moving in the direction of arrow W (depending on the amount of polishing), the rotating grindstone body 10 is tilted, and the angle of the side surface of the rotating grindstone body 10 with respect to the rotation axis L2 of the round blade unit 130 is changed. Accordingly, the contact angle of the grindstone tip portion 12 formed on the side surface of the rotating grindstone body 10 with the round blade changes, so the angle of inclination of the edge of the round blade represented by the C value and the H value is Although the tilt angle α of the rotation axis L2 of the spindle shaft 22 does not completely coincide with the tilt angle α, a slight error occurs. However, since the polishing amount is smaller than the diameter of the rotating grindstone body 10, the error can be ignored.
[0040]
Hereinafter, the experimental results under the polishing conditions of 300 rpm for the round blade unit, 350 rpm for the rotating grindstone body, and the kind of grindstone: manufactured by Nagoya Dia. SD7000 will be described.
[0041]
1. About uneven polishing
As shown in FIG. 6, the C value of the cutting edge of the same round blade at the first measurement location A, the second measurement location B, and the third measurement location C obtained by dividing the round blade into three equal parts in the circumferential direction. As shown in FIG. 7, the variation in the C value is approximately ± 0.1 μm at each polishing amount (polishing amounts: 0.05 mm, 0.10 mm, 0.15 mm, 0.20 mm). It can be seen that the grindstone is polished with a constant side pressure (polishing conditions) following the runout of the cutting edge of the round blade in the direction of the rotation axis, and it is understood that there is almost no polishing unevenness at the cutting edge. At this time, the runout width in the rotation axis direction of the cutting edge of the round blade is about ± 5 μm.
[0042]
2. About relationship between polishing amount and C value
As shown in FIG. 7, the relationship between the polishing amount and the C value is slightly increased according to the polishing amount even if the polishing amount changes from 0.05 mm to 0.2 mm as shown in FIG. The amount of increase is within 0.5 μm, and the total of the round blade unit transport error (several tens of μm) and the round blade edge touch error (several μm) due to the transport mechanism of the round blade rotation positioning means. Since it is easy to suppress to about 0.05 mm (50 μm), for example, if the target value of C value is 4 μm, processing for finishing the C value within 4 μm ± 0.5 μm is performed by adjusting the polishing time. It turns out that it is easy.
[0043]
3. Relationship between C value and polishing time
As shown in FIG. 8, the C value increases as the polishing time increases. For example, in the vicinity of the polishing time of 60 seconds when the C value is about 4 μm, the change in C value per 10 seconds is from 0.3 μm to 0. It can be seen that it is easy to process the C value with an accuracy of about 4 μm ± 0.5 μm.
[0044]
However, when processing is performed so that the C value is 1 μm or less, the amount of polishing per unit time is too large under the above polishing conditions (the polishing time is 1 for polishing so that the C value is 1 μm or less). It is necessary to change the polishing conditions because the control is performed with an accuracy of seconds or less). For example, it is necessary to change the polishing conditions, such as making the grain size of the grindstone finer, or using a ring spring with weaker stretching force to reduce the side pressure. By changing the polishing conditions as described above, it is also possible to select processing conditions that enable polishing so that the C value is about 0.5 μm.
[0045]
4). About variation of C value of each round blade when round blade unit is polished
As shown in FIG. 9, from the 15th round blade to the 25th round blade of the round blade unit, the target value of C value is set to 4 μm, and from the 28th round blade to the 38th round blade of the round blade unit. As a result of processing up to a target value of C value of 6 μm, the range of C value variation from the 15th round blade to the 25th round blade is 3.9 μm to 4.3 μm, and the 28th round of the round blade unit The range of C value variation from the blade to the 38th round blade is 5.8 μm to 6.4 μm, and it can be seen that the C value can be processed with an accuracy of ± 0.5 μm with respect to the target value.
[0046]
In addition, as a result of the above experiment, the effect of prolonging the life of the cutting edge by polishing the cutting edge into a shape with less clogging of the grindstone and high cutting quality even if 30 or more round blades are continuously polished. You can also expect.
[0047]
Further, in the above embodiment, the ring spring is used as the biasing means, but instead of the ring spring, various elastic biasing means such as a disc spring or a rubber O-ring, or biasing means that performs the same function is used. Can do.
[0048]
Moreover, in the said embodiment, although the example of embodiment which integrated the biasing means and the grindstone rotating means (spring receiving disk) was shown, the biasing means 10 and the grinding | polishing rotation means 20 are comprised separately. For example, the rotating grindstone rotated by the grindstone rotating means may be urged without rotating the urging means.
[0049]
FIG. 10 is a diagram showing a schematic configuration of a main part of the polishing apparatus which is a main part of the polishing apparatus according to the second embodiment of the present invention. The polishing apparatus of the second embodiment is obtained by changing the configuration of the spindle holder, the rotating grindstone body, and the biasing means disposed on the spindle shaft in the first embodiment. The configuration is the same as that of the first embodiment. The application of this polishing apparatus to the round blade unit polishing apparatus for polishing the cutting blade of the lower round blade unit of the magnetic tape cutting apparatus is the same as that of the first embodiment.
[0050]
The polishing apparatus main body of the second embodiment includes a rotating grindstone body 80 and a rotating means 50 that rotates the rotating grindstone body 80, and the rotating grindstone body 80 can be elastically displaced in the direction of the rotation axis of the rotating means 50. A ring-shaped grindstone portion 83 is provided.
[0051]
The rotating means 50 includes a rotating spindle unit 21 that transmits a rotating force for rotating the rotating grindstone body 10 and a polishing motor. The polishing motor fixes the spindle shaft 22 of the rotating spindle unit 20 to the spindle shaft 22. It is rotated through a belt hung on the pulley.
[0052]
The rotating grindstone body 80 is formed by a boss portion 81 fitted to the spindle shaft 22, a disc body 82 fixed to the boss portion 81, and a grindstone layer laminated on the outer peripheral portion of the side surface of the disc body 82. And a ring-shaped grindstone portion 83. The disk 82 is made of a thin steel plate (about 0.2 mm), has elasticity in the rotation axis direction, and can be displaced in the rotation axis direction.
[0053]
The boss 81 of the rotating grindstone 80 is fitted to the spindle shaft 22 by a mechanism using a key groove and a key, is fixed by screws 23 and is rotated by driving the spindle shaft 22.
[0054]
The main body of the polishing apparatus is mounted on the round blade unit polishing apparatus, and the rotation axis L1 of the spindle shaft 22 is set to be inclined at an angle α with respect to the rotation axis L2 of the round blade unit as in the first embodiment. The round blade of the round blade unit can be polished.
[0055]
Here, polishing of the cutting edge of the round blade by the elastically displaceable ring-shaped grindstone portion 83 will be described.
[0056]
When the round blade is polished by this polishing apparatus, the grinding wheel portion 83 forms a plane by the centrifugal force when the rotating grindstone body 80 is rotated, but the round blade of the round blade unit 130 is brought into contact with the grinding stone portion 83, Further, when the round blade unit 130 is conveyed in a direction toward the grindstone portion 83 by a predetermined amount of polishing, the vicinity S of the region where the grindstone portion 83 contacts the first round blade 131 is elastically deformed as shown in FIG. The reaction force of this elastic deformation becomes an urging force, and the component of the centrifugal force generated in the grinding wheel portion 83 due to the rotation of the rotating grindstone body 80 becomes the urging force, so that the grinding stone portion 83 is directed toward the round blade. Polishing is performed in the energized state. At this time, the fluctuation of the biasing force with respect to the change in the polishing amount is small, and even if the cutting edge of the round blade is shaken or there is an error in the polishing amount, the grindstone portion 83 follows the round blade. This round blade can be polished, and the polishing amount of the blade edge can be accurately controlled.
[0057]
As shown in FIG. 12, a disk portion 86 made of a thin steel plate (thickness: about 0.2 mm) is fixed around a boss portion 85 fitted to the spindle shaft 22, and this disk portion is further fixed. By forming a highly rigid grindstone portion 87 around 86, the disc portion 86 which is a part of the rotating grindstone body other than the grindstone portion 87 is elastically deformed without deforming the grindstone portion 87. Even if a rotating grindstone configured to displace, that is, to displace the grindstone portion 87 elastically, the same effect as described above can be obtained.
[0058]
In addition, it is not always necessary to use a steel thin plate material for the disc portion that supports the grindstone portion, and any material may be used as long as it is an elastically deformable material. Further, a deformable material such as a fibrous material can be used for the disc portion that supports the grindstone portion, although it is not elastically deformed. If such a material is used for the disc portion, at least when the grindstone portion is displaced during the rotation of the rotating grindstone body, it is possible to generate a restoring force that attempts to restore this displacement.
[0059]
The above polishing method is used for equipment and parts used for general grinding or polishing.
It can be used, and the production cost of the rotating grindstone body and the polishing apparatus can be kept low.
[0060]
In addition, the above polishing method allows selection of many factors that control the polishing amount (for example, side pressure, grinding wheel mesh, polishing time, grinding wheel rotational speed, rotational speed of the workpiece, etc.) and setting appropriate polishing conditions. Thus, the C value of the cutting edge can be accurately controlled to any value.
[0061]
In the above embodiment, the object to be polished is a thin cutting blade. However, the present invention is not limited to a thin cutting blade, and can be applied to polishing of a round blade or a flat blade for cutting a thick object, for example. is there. In addition to the magnetic tape raw material, for example, the cutting blade may be a photosensitive material such as a photographic film mainly made of a non-metallic material or a photographic printing paper, a metal foil made of a metallic material, and a battery or a cartridge. Examples include a metal thin plate that is an exterior.
[0062]
In the above embodiment, when each round blade of the round blade unit is polished, the round blade unit is moved with respect to the polishing apparatus main body. However, the polishing apparatus main body is moved to polish each round blade. It may be.
[0063]
Further, as the rotational speed of the rotating grindstone body is decreased, the R shape of the apex portion of the substantially perpendicular corner portion of the cutting edge can be increased, so that the minute apex portion can be adjusted by adjusting the rotational speed. It is also possible to control the R shape.
[Brief description of the drawings]
FIG. 1 is a front view showing a schematic configuration of a round blade unit polishing apparatus according to an embodiment of the present invention.
FIG. 2 is a side view of a round blade unit polishing apparatus.
FIG. 3 is an enlarged view showing how a round blade is polished.
FIG. 4 is an enlarged view showing a state in which a rotating grindstone moves when a round blade is polished.
FIG. 5 is a diagram showing details of C value and H value.
FIG. 6 is a diagram showing measurement points A, B, and C obtained by dividing a round blade into three equal parts in the circumferential direction.
FIG. 7 is a graph showing the C value variation of the cutting edge of the same round blade and the relationship between the amount of polishing and the C value.
FIG. 8 is a graph showing the relationship between C value and polishing time
FIG. 9 is a diagram showing variation in C value of each round blade when the round blade unit is polished.
FIG. 10 is a diagram showing a configuration of a rotating grindstone having a ring-shaped grindstone that can be elastically deformed in the rotation axis direction;
FIG. 11 is a diagram showing a state in which the grinding wheel portion contacts the round blade during polishing and the vicinity of the contact area is elastically deformed.
FIG. 12 is a diagram showing a rotating grindstone having a grindstone portion that can be elastically displaced
FIG. 13 is a diagram showing a schematic configuration of a magnetic tape cutting device.
[Explanation of symbols]
10 Rotating whetstone
11 Whetstone base plate
12 Grinding wheel
20 Wheel rotation means
22 Spindle shaft
30 Energizing means
100 polishing equipment
130 Round Blade Unit

Claims (2)

In the polishing method of the cutting blade for polishing the cutting blade with a rotating rotating grindstone body,
Polishing cutting blade, wherein the grinding wheel body, wherein the cutting blade, polishing the portion a press while elastically deforming against by the cutting blade of the rotary grindstone body in the rotation axis direction of the grinding wheel body Method. In a polishing apparatus for a cutting blade comprising a rotating grindstone body and a rotating means for rotating the rotating grindstone body,
The rotary grindstone body polishing apparatus of the cutting blade, characterized in that those having a disk portion of the elastic deformation available-for annular in the direction of the rotation axis of the rotating means during rotation.

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