JP2007326289A - Cutting tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cutting tool for which the fall of the cutting speed by the motion of a saw blade is suppressed. <P>SOLUTION: This cutting tool is equipped with a motor, the saw blade 6 which keeps cutting a member to be processed in the cutting direction by being driven by the motor, and a base section 4 which is arranged on the member to be processed, and moves together with the saw blade 6 in the cutting direction. The base section 4 is constituted by including a base 41 and a recess section 42. In this case, the base 41 is constituted of an approximately flat plate, and has a facing surface 41A which faces the member to be processed. The recess section 42 is provided on the facing surface 41A of the base 41, and is equipped with a corner section 42A which suppresses the sliding of the base section 4 in the anti-cutting direction to the member to be processed. The cutting tool which is constituted in this manner is provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cutting tool, and more particularly to a cutting tool having a base that comes into contact with a workpiece.

  Cutting tools such as portable circular saws and jigsaws for cutting workpieces having a large area such as slate plates and veneer plates, and cutting tools such as saver saws for cutting pipes, squares and the like are known.

As shown in Patent Document 1, these cutting tools are provided with a substantially plate-shaped base, a base tool that presses the base against a workpiece, slides the base, and is a tip tool that protrudes from the contact surface of the base. A cutting operation is performed by cutting and cutting a workpiece with a certain saw blade or the like. Since the base is provided with a sliding contact sheet made of a synthetic resin having a low friction property to reduce friction on the surface abutting on the workpiece, the base is attached when the operator urges the cutting tool. Even if the power is small, it can be cut easily.
JP 2001-315075 A

  In conventional cutting tools, the saw blade part of the tip tool is cut by reciprocating or rotating in a direction intersecting with the cutting advance direction (cutting direction). If the member is not biased, the cutting efficiency tends to decrease. Therefore, when the force with which the operator urges the cutting tool in the cutting direction is weak, the cutting tool may be pushed back to the anti-cutting direction side by the reaction force at the time of cutting the saw blade portion. As a result, the cutting efficiency is lowered, and as a result, the cutting speed may be slow.

  Then, an object of this invention is to provide the cutting tool which prevented the movement to the anti-cutting direction of the tool by operation | movement of a saw blade, and suppressed the fall of the cutting speed.

  In order to solve the above-described problems, the present invention provides a motor, a tip tool driven by the motor to cut a workpiece in the cutting direction, and the tip tool disposed on the workpiece and in the cutting direction. A base portion that moves together, and the base portion is formed of a substantially flat plate and has a facing surface that faces the workpiece, and the workpiece is provided on the facing surface of the base. On the other hand, there is provided a cutting tool configured to include sliding suppression means for suppressing sliding of the base portion in the anti-cutting direction.

  According to such a configuration, even when the force with which the operator urges the cutting tool in the cutting direction is weak, the sliding restraining means receives the reaction force generated when the tip tool performs cutting, and the reaction force is reduced. It is possible to prevent the cutting tool from moving in the cutting direction.

  In the above configuration, the sliding suppression means is a convex portion formed on the facing surface of the base and having a corner portion that can be hooked on the workpiece when the base portion is moved in the anti-cutting direction. Or you may be comprised by the recessed part.

  According to such a configuration, when the base portion is biased in the anti-cutting direction by the reaction force of the tip tool, the corner portion is hooked on the workpiece, so that the reaction force can be received.

  Further, in the above configuration, the sliding suppression means includes a wheel provided on the base and a one-way clutch interposed between the wheel and the base, and the wheel has a part of the outer ring facing the opposing surface. And the axle is arranged in a direction perpendicular to the cutting direction, and the one-way clutch allows only the wheel to rotate in the cutting direction and restricts the rotation in the anti-cutting direction. It may be.

  According to such a configuration, when the operator urges the cutting tool in the cutting direction, the wheel serves as a guide, reducing friction between the base portion and the workpiece, and reducing the urging force. it can. Further, when the base portion is biased in the anti-cutting direction by the reaction force of the tip tool, the reaction force can be received by the frictional force between the wheel and the workpiece.

  Moreover, it is preferable that this wheel is provided with the viscoelastic member in the location contact | abutted with this to-be-processed member of this outer ring | wheel.

  According to such a configuration, the frictional force between the wheel and the workpiece can be increased, and a larger reaction force of the tip tool can be received.

  Moreover, it is preferable that this base part is provided with the adjustment mechanism which adjusts the protrusion amount from this opposing surface of this outer ring | wheel.

  According to such a configuration, when the wheel interferes with the cutting process, the wheel can be prevented from protruding from the base.

  Further, in the cutting direction, it is preferable that the sliding suppression means is disposed in front of the tip tool.

  According to such a configuration, it is possible to suppress a pivot point from being formed at a position on the rear end side of the tip tool on the surface of the base that contacts the workpiece. When cutting with a cutting tool, a retreating force is applied to the cutting tool via the tip tool. In this case, due to the retreating force, a rotational force is generated in the base that presses the rear end side of the base against the workpiece and lifts the front end side of the base. However, since the sliding restraining means is provided on the front end side of the base and not on the rear end side, friction may be generated between the sliding restraining means and the workpiece to serve as a pivot point of rotation. It is suppressed.

  According to the cutting tool of the present invention, it is possible to increase the cutting efficiency and increase the cutting speed because the base retreat is suppressed during cutting.

  Hereinafter, a cutting tool according to a first embodiment of the present invention will be described with reference to FIGS. A jigsaw 1 which is a cutting tool shown in FIG. 1 is mainly composed of a housing 2, a motor 3, a base part 4, a drive part 5, and a saw blade 6. It is a tool that cuts through. A direction in which the jigsaw 1 advances is defined as a cutting direction.

  The housing 2 is composed of a frame made of aluminum or the like, and includes a handle 21 that is a place to be gripped by an operator at a position that is a rear end portion of the jigsaw 1. A trigger 22 for controlling power supply to the motor 3 is provided at the base portion of the handle 21. Further, an arm portion 21 </ b> A that holds a roller holder 55 described later is extended toward the front side in the cutting direction from a position in the vicinity of a portion in contact with the base portion 4 of the housing 2.

  The motor 3 is disposed in the housing 2, and an output shaft 31 extends from one end thereof. A pinion gear 31 </ b> A is provided at the tip portion of the output shaft 31. A cooling fan 32 is provided on the proximal end side of the output shaft 31 to cool the motor 3.

  As shown in FIG. 2, the base portion 4 includes a base 41 in which a concave portion 42 is formed. As shown in FIG. 2, the base portion 4 is formed in a substantially rectangular shape as shown in FIG. 2, and a surface facing the wood board W (FIG. 4) as a workpiece is defined as a facing surface 41A. It is located between the wood board W and the housing 2 so that the longitudinal direction of the rectangle coincides with the cutting direction. Hereinafter, the vertical direction is defined with the direction from the housing 2 toward the base portion 4 and the wood board W as the downward direction and the opposite direction as the upward direction. A direction intersecting with the vertical direction and the cutting direction is defined as a horizontal direction.

  The concave portion 42 is configured by a groove portion formed in the short side direction on the facing surface 41A, and a plurality of the concave portions 42 are arranged in alignment in the longitudinal direction. As shown in FIG. 3, the groove forming the recess 42 is formed in a valley shape having a substantially V-shaped cross section, and the deepest portion of the valley is located on the front side in the cutting direction with respect to the opening portion of the valley. Has been. Therefore, a corner portion 42A having an acute angle toward the rear side in the cutting direction is formed on the bank portion located on the front side in the cutting direction among both banks of the groove portion forming the recess 42. When the base 41 is slid to the rear side in the cutting direction, the corner portion 42A is hooked on the unevenness formed on the surface of the wood board W (FIG. 4) to prevent sliding to the rear side. be able to.

  In the base 41, an opening 4a is formed at the edge on the front side in the cutting direction by cutting. A recessed portion with respect to the facing surface 41A is formed behind the opening 4a in the cutting direction, and a screw 43 for fixing the base portion 4 to the housing 2 is provided in the recessed portion.

  As shown in FIG. 1, the saw blade 6 is attached to a plunger 54 described later so that the blade portion faces the front side in the cutting direction and the back portion faces the rear side in the cutting direction.

  The drive unit 5 mainly includes a gear unit 51, a transmission unit 52, a holder 53, a plunger 54, and a roller holder 55. The gear portion 51 is configured by connecting a spur gear 51A meshing with the pinion gear 31A and a cam 51B so as to be coaxial, and is rotatably supported by the housing 2 by a spindle 51D. Further, a pin 51C is provided on the side surface of the spur gear 51A on the side opposite to the cam 51B so as to protrude from the spindle 51D in a different axis and parallel.

  The transmission part 52 is comprised from the substantially rectangular board | plate material. A long hole 52a is formed in the body portion of the transmission portion 52. The long hole 52a has a major axis in the short direction of a substantially rectangular shape and a short axis in the long direction of the substantially rectangular shape. The hole 52a is formed so that the diameter of the short axis is substantially the same as the diameter of the cam 51B. A cam 51B is inserted into the elongated hole 52a, and the transmission portion 52 can reciprocate in the substantially rectangular longitudinal direction in accordance with the rotation of the cam 51B.

  The holder 53 is arranged in the vertical direction, and is pin-bonded to the housing 2 by a pin 53A extending in the left-right direction at the upper end, and supported by the housing 2 via a spring 53B arranged at the front side in the cutting direction of the holder 53 at the lower end. ing. Therefore, the holder 53 can be rotated with the upper end as a fulcrum, and is urged rearward in the cutting direction by the spring 53B. In addition, support portions 53C and 53C for slidably supporting the plunger 54 are provided at the upper end portion and the lower end portion of the holder 53, respectively.

  The plunger 54 is configured in a substantially rod shape and is slidably supported by the support portions 53C and 53C so that the longitudinal direction is the vertical direction. A holding portion 54 </ b> A for holding the saw blade 6 is provided at the lower end portion of the plunger 54. A receiving portion 54B that defines a groove extending in the left-right direction is provided at a portion located between the upper end side support portion 53C and the lower end side support portion 53C of the plunger 54, and the groove of the receiving portion 54B is provided. A pin 51C is inserted inside. Since the pin 51C is allowed to move in the left-right direction within the groove of the receiving portion 54B and the vertical movement is restricted, the receiving portion 54B can only move up and down in accordance with the movement of the pin 51C. Therefore, the rotation of the pin 51C around the spindle 51D can be converted into the vertical movement of the plunger 54.

  The roller holder 55 is rotatably provided at the tip of the arm portion 21A by a pin 55C extending in the left-right direction. A roller 55A that comes into contact with the back portion of the saw blade 6 is provided at one end on the lower side of the roller holder 55. From the pin 55C position of the roller holder 55 to the roller 55A position, the roller 55A is lowered toward the cutting direction. It is configured to be curved so as to be convex. The other end, which is the upper end of the roller holder 55, is provided with an abutting portion 55B that abuts on the lower end of the transmission portion 52. It is configured. The contact portion 55B is configured to extend to the rear side in the cutting direction so as to be substantially orthogonal to the substantially linear shape on the other end side of the roller holder 55. Therefore, when the contact portion 55B is urged by the transmission portion 52, the one end of the roller holder 55 and the roller 55A can move forward in the cutting direction with the pin 55C as the rotation center.

  In the gear portion 51, a pin 51C and a cam 51B are arranged so that the vertical movement of the transmission portion 52 and the vertical movement of the plunger 54 are in opposite phases.

  In the jigsaw 1 configured as described above, when cutting the wood board W, the operator pulls the trigger 22 while holding the handle 21 and pushes the jigsaw 1 in the cutting direction, and prevents the jigsaw 1 from being violated during cutting. In order to do so, it is biased downward. At this time, as shown in FIG. 4, the plunger 54 moves upward from the bottom dead center position 6 ′, moves the saw blade 6 upward, and grinds the wood board W. At this time, since the transmission unit 52 moves downward, in the roller holder 55, the roller 55A moves forward in the cutting direction and biases the saw blade 6 in the cutting direction. Therefore, since the saw blade 6 is urged by the roller 55A in the cutting direction, more specifically, the blade portion of the saw blade 6 is urged against the wood board W, the cutting efficiency can be increased.

  Since the saw blade 6 is urged to the wood board W, the jigsaw 1 including the saw blade 6 as a reaction force is urged to the rear side in the cutting direction, which is the anti-cutting direction. However, since the base 41 is prevented from sliding backward in the cutting direction by the corner portion 42A (FIGS. 2 and 3), the jig 41 is suppressed from being pushed back by the reaction force. Therefore, when cutting, the saw blade 6 always performs the cutting while being urged by the wood board W, and the reduction of the cutting efficiency due to the reduction of the urging force of the saw blade 6 to the wood board W is suppressed, and the cutting is performed. You can speed up.

  Further, as shown in FIG. 5, when the saw blade 6 moves downward after being raised to the top dead center position 6 ″, the transmission portion 52 moves upward, so in the roller holder 55, the roller 55A is in the cutting direction. It becomes possible to move to the rear side. Since the plunger 54 is urged rearward in the cutting direction by the spring 53B via the holder 53, a gap is formed between the cutting portion of the wood board W and the blade portion of the saw blade 6. Therefore, it is suppressed that the blade portion of the saw blade 6 and the wood board W come into contact with each other and become resistance when the saw blade 6 moves downward.

  In the first embodiment, the concave portion 42 is used as the sliding restraining means. However, as shown in FIGS. 6 and 7, the sliding restraining means may be constituted by the convex portion 44. The convex portion 44 protrudes from the facing surface 41A of the base 41, and has a corner portion 44A having an acute angle toward the rear side in the cutting direction at the rear side portion in the cutting direction. Therefore, when the base 41 is urged rearward in the cutting direction, the corner portion 44A is hooked on the unevenness formed on the surface of the wood board W (FIG. 4) to prevent sliding to the rear side. it can.

  Next, the cutting tool which concerns on 2nd embodiment of this invention is demonstrated based on FIG. 8 thru | or FIG. As shown in FIG. 8, the jigsaw 101, which is a cutting tool according to the second embodiment, has the same configuration as the jigsaw 1 according to the first embodiment except for the configuration related to the sliding restraining means. Therefore, 100 is added to the reference numerals according to the first embodiment, and the description thereof is omitted. As shown in FIG. 8 and FIG. 9, in the base portion 104, a pair of wheels 142, part of which protrudes from the facing surface 104 </ b> A and can be brought into contact with the workpiece, at the front side in the cutting direction of the opening 104 a 142 are arranged side by side in the left-right direction.

  As shown in FIGS. 10 and 11, the wheel 142 is configured such that a one-way clutch 144 is attached to an axle 143 and a ring 146 made of resin having viscoelasticity is attached to an outer ring portion of the one-way clutch 144. Has been.

  As shown in FIG. 12, the one-way clutch 144 is a known device mainly composed of an inner ring 144A, an outer ring 144B, a plurality of balls 144C, and a plurality of springs 144D corresponding to the number of the plurality of balls 144C. It is. In the one-way clutch 144, the outer ring 144B can rotate relative to the inner ring 144A and the axle 143 when the outer ring 144B rotates in the arrow A in the figure, but the outer ring 144B will rotate in the direction of the arrow B in the figure. The inner ring 144A, the axle 143, and the outer ring 144B are configured to rotate integrally.

  As shown in FIG. 8, the wheel 142 is arranged on the jigsaw 101 so as to rotate in the direction of arrow A when the jigsaw 101 moves forward in the cutting direction. Accordingly, the wheel 142 can rotate when the jigsaw 101 moves forward in the cutting direction, but the wheel 142 cannot rotate when the jigsaw 101 moves backward in the cutting direction, and slides. Since the outer ring portion of the wheel 142 is a ring 146 that is a resin having viscoelasticity, it adheres to the workpiece and suppresses sliding. Therefore, the movement of the jigsaw 101 to the rear side in the cutting direction is restricted.

  The base 104 has a pair of rectangular openings 104b and 104b on the front side in the cutting direction of the opening 104a so that a part of the wheel 142 can protrude from the facing surface 141A in a state where the axle shaft 143 is located on the opposite surface 141A side. It is formed in parallel with the position. A pair of support portions 145 and 145 (FIG. 8) for pivotally supporting the axle shaft 143 are provided on the periphery of the pair of openings 104b and 104b so as to protrude from the base 104.

  As shown in FIGS. 8 and 11, the support portion 145 includes a pair of arm portions 145A and 145A, a pair of springs 145B and 145B, and a pair of screws 145C and 145C. The pair of arm portions 145A and 145A are disposed so as to protrude from the base at edge portions located in the left-right direction of the opening 104b. The pair of arm portions 145A and 145A are formed with grooves 145a and 145a that open upward and extend in the left-right direction, and springs 145B and 145B are disposed in the grooves so as to be urged upward. One end and the other end of the axle shaft 143 are inserted in the grooves 145a and 145a and above the springs 145B and 145B. The inner surface defining the groove 145a is internally threaded from the upper opening of the groove 145a toward the lower side, and can be screwed into a pair of screws 145C and 145C.

  By screwing the pair of screws 145C and 145C into the grooves 145a and 145a and screwing them downward, one end and the other end of the axle shaft 143 can be urged downward. Since one end and the other end of the axle shaft 143 are biased upward by springs 145B and 145B, the axle shaft 143 can be supported by the support portion 145. Further, by protruding and retracting the screws 145C and 145C, it is possible to change the protruding amount of the wheel 142 from the facing surface 141A with respect to the facing surface 141A.

  When the workpiece is cut by the jigsaw 101 having the above-described configuration, the wheel 142 serves as a guide, reduces friction between the base 141 and the workpiece, and reduces the biasing force by which the operator biases the jigsaw 101. can do. Since the saw blade 106 is urged to the workpiece during cutting, the jigsaw 101 including the saw blade 106 is urged to the rear side in the cutting direction, which is the counter-cutting direction, as a reaction force. However, since the base 141 is prevented from sliding backward in the cutting direction by the wheels 142, the jigsaw 101 is suppressed from being pushed back by the reaction force. Therefore, during cutting, the saw blade 106 always performs cutting while being urged by the workpiece, so that the cutting efficiency can be increased and the cutting speed can be increased.

  Further, the wheel 142 is disposed in front of the saw blade 106 in the cutting direction. The operator holds the handle 121 behind and above the saw blade 106 to urge the jigsaw 101. Therefore, the pressure from the facing surface 141A to the workpiece member is the most in the facing surface 141A that comes into contact with the workpiece, from the direction in which the operator urges the jigsaw 101 by the handle 121 and the positional relationship of the saw blade 106 with respect to the handle 121. The portion to be added is a position on the front side in the cutting direction of the saw blade 106.

  The higher the pressure from the base 141 to the workpiece, the greater the frictional force. By placing the wheel 142 at this position, the frictional force during sliding between the wheel 142 and the workpiece can be increased. More preferably, the jigsaw 101 can be prevented from sliding backward in the cutting direction.

  When cutting with the jigsaw 101, a force for retracting the jigsaw 101 is applied via the saw blade 106. In this case, due to the retreating force, a rotational force is generated in the base 141 so that the rear end side of the base 141 is pressed against the workpiece and the front end side of the base 141 is lifted. However, since the wheel 142 is provided on the front end side of the base 141 and is not provided on the rear end side, generation of friction between the wheel 142 and the member to be processed and a rotation fulcrum are suppressed. . Therefore, the front end of the base 141 is prevented from being lifted by rotation.

  Further, since the wheel 142 eliminates the ring 146, which is a viscoelastic material, at the place where it contacts the workpiece, even if the wheel 142 contacts the workpiece during work, the wheel 142 causes damage to the workpiece. Is suppressed. Therefore, the finishing material such as a decorative board can be suitably operated without being damaged. Further, the amount of protrusion of the wheel 142 can be changed. Therefore, when cutting one corner of the workpiece, for example, when one wheel 142 contacts the workpiece but the other wheel 142 does not contact the workpiece, at least one of the wheels 142 does not protrude. By adjusting as described above, it is possible to suppress that only one of the wheels 142 abuts and it becomes difficult to perform the cutting process.

  The cutting tool by this invention is not limited to embodiment mentioned above, A various deformation | transformation and improvement are possible in the range described in the claim. For example, although the first and second embodiments have been described based on jigsaws, the present invention is not limited to this, and the present invention may be applied to a tabletop circular saw 201 as shown in FIG. In the tabletop circular saw 201, the base 241 is disposed on the front side in the cutting direction of the cutting blade 206 on which the wheel 242 rotates, and thereby the same effect as in the second embodiment can be obtained. Further, the tabletop circular saw 201 shown in FIG. 13 may have a concave portion or a convex portion provided with corner portions which are the sliding suppression means according to the first embodiment.

  In the first embodiment, a sliding restraining means having corners is used, and in the second embodiment, a sliding restraining means using a one-way clutch and wheels is used. These sliding suppression means do not necessarily need to be used alone, and may be used in combination. Moreover, in 2nd Embodiment, although the wheel 142 was provided only in the cutting direction front side from the cutting blade 106, you may provide the wheel 142 in the cutting direction front side and rear side of the cutting blade 106, respectively.

  The cutting tool of the present invention can be applied to a portable power tool having a base and cutting the base member in contact with a workpiece, for example, a jigsaw, a portable circular saw, or a saver saw.

The side surface and principal part sectional drawing of the cutting tool which concern on 1st embodiment of this invention. The bottom view of the cutting tool which concerns on 1st embodiment of this invention. Sectional drawing along the III-III line of FIG. The fragmentary sectional view which shows the tip tool periphery of the cutting tool which concerns on 1st embodiment of this invention (during tip tool raise). The fragmentary sectional view which shows the tip tool periphery of the cutting tool which concerns on 1st embodiment of this invention (during tip tool lowering). The bottom view which shows the further example of the cutting tool which concerns on 1st embodiment of this invention. Sectional drawing along the VII-VII line of FIG. The side surface and principal part sectional drawing of the cutting tool which concern on 2nd embodiment of this invention. The bottom view of the cutting tool which concerns on 2nd embodiment of this invention. Sectional drawing along the XX line of FIG. Sectional drawing along the XI-XI line of FIG. Sectional detail drawing which shows the one-way clutch of the cutting tool which concerns on 2nd embodiment of this invention. The side view which shows the state which applied the cutting tool which concerns on this invention to a portable circular saw.

Explanation of symbols

1. ・ Jigsaw 2 ・ ・ Housing 3 ・ ・ Motor 4 ・ ・ Base 4a ・ ・ Opening 5 ・ ・ Drive 6 ・ ・ Saw Blade 21 ・ ・ Handle 21A ・ ・ Arm 22 ・ ・ Trigger 31 ・ ・ Output shaft 31A ··· Pinion gear 32 · · Cooling fan 41 · · Base 41A · · Opposite surface 42 · · concave portion 42A · · corner portion 43 · · screw 44 · · convex portion 44A · · corner portion 51 · · gear portion 51A · · Spur gear 51B ·· Cam 51C ·· Pin 51D ·· Spindle 52 ·· Transmission portion 52a ·· Long hole 53 ·· Holder 53A ·· Pin 53B ·· Spring 53C ·· Support portion 54 ·· Plunger 54A ·· Holding portion 54B ·· Receiving part 55 ·· Roller holder 55A ·· Roller 55B ·· Contact part 55C ·· Pin

Claims (6)

A motor,
A tip tool driven by the motor to cut the workpiece in the cutting direction;
A base portion disposed on the workpiece and moving together with the tip tool in the cutting direction;
The base portion is formed of a substantially flat plate and has a facing surface that faces the workpiece, and the base portion is provided on the facing surface of the base in the anti-cutting direction of the base portion with respect to the workpiece. The cutting tool characterized by including the sliding suppression means which suppresses sliding.   The sliding suppression means is formed by a convex portion or a concave portion that is formed on the facing surface of the base and has a corner portion that can be hooked on the workpiece when the base portion is moved in the anti-cutting direction. The cutting tool according to claim 1, wherein the cutting tool is provided. The sliding suppression means has a wheel provided on the base, and a one-way clutch interposed between the wheel and the base,
The wheel is arranged in a direction in which a part of the outer ring protrudes from the facing surface and comes into contact with the workpiece and the axle is orthogonal to the cutting direction.
The cutting tool according to claim 1, wherein the one-way clutch only allows the wheel to rotate in the cutting direction and restricts the rotation in the anti-cutting direction.   The cutting tool according to claim 3, wherein the wheel includes a viscoelastic member at a location where the wheel abuts on the workpiece.   The cutting tool according to claim 3, wherein the base portion includes an adjustment mechanism that adjusts a protruding amount of the outer ring from the facing surface.   The cutting tool according to any one of claims 1 to 5, wherein in the cutting direction, the sliding suppression means is disposed in front of the tip tool.

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