Disclosure of Invention
It is an object of the present invention to provide a reciprocating cutting tool, particularly a jigsaw, having a blade raising feature optimized for blade support.
The present invention provides a reciprocating cutting tool, comprising:
a housing; a motor disposed in the housing; the reciprocating mechanism is arranged in the shell and comprises a reciprocating rod which is driven by a motor to reciprocate along an axis X relative to the shell and a saw blade connected with the reciprocating rod; the cutter lifting component is arranged in the shell; the transmission component is arranged between the cutter lifting component and the reciprocating mechanism; the cutter lifting component drives the transmission component to press the saw blade towards the cutting direction of the saw blade; the cutter lifting component comprises a connecting plate driven by a motor to move relative to the shell and a cutter lifting plate movably connected to the connecting plate, and the cutter lifting plate is pivotally connected to the connecting plate.
Furthermore, the transmission component comprises a guide wheel bracket and a guide wheel installed on the guide wheel bracket, a pivotal shaft is arranged on the shell, the guide wheel bracket is pivotally installed on the shell through the pivotal shaft, the guide wheel bracket is provided with a bracket top end adjacent to the knife lifting plate and a bracket bottom end adjacent to the saw blade, which are respectively located on two radial sides of the pivotal shaft, and the bracket bottom end is connected with the guide wheel. And a bracket torsional spring is arranged between the guide wheel bracket and the shell, and the bracket torsional spring presses the guide wheel bracket to pivot, so that the top end of the bracket is close to the knife lifting plate, and the bottom end of the bracket and the guide wheel are far away from the saw blade.
Further, the connecting plate is driven by the motor to reciprocate along the X axis. The cutter lifting plate comprises a cutter lifting tail end and a cutter lifting plate side perpendicular to the cutter lifting tail end, the cutter lifting plate is connected with a cutter lifting plate torsion spring, and the cutter lifting plate torsion spring presses the cutter lifting tail end and the connecting plate to be parallel to the axis X.
The operating element is connected with a shifting lever, and the operating element selectively moves the tail end of the lifting knife from a supporting position, which is parallel to the axis X, of the connecting plate to a releasing position, which forms an included angle smaller than 180 degrees between the tail end of the lifting knife and the connecting plate, through the shifting lever. The operating element is connected with a cam, the cam is provided with a pivot axis and a high-level surface and a low-level surface which are positioned on the periphery of the cam, the distance from the high-level surface to the pivot axis of the cam is greater than the distance from the low-level surface to the pivot axis of the cam, the operating element drives the cam to pivot around the pivot axis of the cam, the high-level surface and the low-level surface selectively face the top end of the support, and when the high-level surface faces the top end of the support, the cam presses the guide wheel to contact the saw blade; when the low-level surface faces the top end of the support, the support torsion spring presses the top end of the support to pivot towards the low-level surface, and the guide wheel leaves the saw blade.
Further, when the cutter lifting plate is located at the supporting position, the tail end of the cutter lifting plate is driven by the connecting plate to reciprocate between a highest position and a lowest position on an axis X line, the cam is provided with three high-position surfaces with distances sequentially increasing from the pivot axis, and when the three high-position surfaces face the guide wheel support, the three high-position surfaces are located between the highest position and the lowest position of the tail end of the cutter lifting plate in the axis X direction.
Furthermore, when the operating element shifts the tail end of the cutter lifting to a release position, the cam is driven to pivot, and the low-level surface of the cam faces the top end of the bracket.
Further, a rotating handle for controlling the reciprocating rod to rotate around the axis X is included; an operating member provided on the housing, the operating member being connected to the rotation lock and operable to move the rotation lock from a fixed position restricting rotation of the reciprocating lever to a rotational position allowing rotation of the reciprocating lever. The reciprocating cutting tool also comprises a gear which is connected with the operating element and pivots relative to the shell, the rotary locking piece is a rack which is arranged in the shell and matched with the gear along the axis X direction, the rotary handle is provided with an engaging part, and the shape of the tail end of the rack is matched with the shape of the engaging part of the rotary handle; the operating element can be operated to drive the gear to pivot, so that the rack is driven to move along the axis X direction to be meshed with the meshing part of the rotating handle. When the rotating handle rotates to the position that the cutting surface of the saw blade is opposite to the longitudinal axis Y of the shell, the meshing part and the rack are positioned on the same straight line.
The guide wheel device has a simple and compact structure, can conveniently move the guide wheel away from the saw blade in the rotating mode and other occasions without a supporting function, and is quick to operate and flexible in use mode.
Drawings
Fig. 1 is a front sectional view of the jigsaw of the present invention.
Fig. 2 is a front view of the jigsaw of the present invention.
Fig. 3 is a schematic structural view of the cutter lifting, rotating and guide wheel limiting mechanism of the present invention.
Fig. 4 is a perspective view of the rotating mechanism of the present invention.
Fig. 5 is a perspective view of the blade raising member of the present invention.
Fig. 6 is a perspective view of the cam of the present invention.
FIG. 7 is a schematic perspective view of the idler bracket of the present invention.
Fig. 8a is a structural diagram of the state of the cutter lifting 0 gear of the invention.
Fig. 8b is a structural diagram of the state of the lifting knife I-position of the invention.
Fig. 8c is a structural diagram of the state of the lifting knife II stage of the present invention.
Fig. 8d is a structural diagram of the state of the lifting knife III stage of the present invention.
FIG. 8e is a structural diagram of the rotating S-gear of the present invention.
Wherein,
1 sweep-saw 2 casing 4 motor
6 handle 8 switch 12 reciprocating lever
13 rectangular end 14 saw blade 104 main shaft
106 bull gear 108 drive shaft 110 chute
202 rotating handle 203 through hole 204 sleeve
205 cross-hole 206 bearing bracket 208 ball bearing
210 bearing projection 221 deep rectangular hole 222 shallow rectangular hole
302 lifting drive shaft 303 lifting component 304 connecting plate
306 lifting knife groove 308 lifting knife plate 309 lifting knife plate torsion spring
310 end 312 side 314 idler support
315 bracket top 316 guide wheel 317 pivot shaft
318 support torsion spring 320 support bottom 402 operating element
404 cam 406 high-level surface 407 arc surface
408 high side 409 low side 410 high side
411 cam disc 412 high-level surface 413 chassis
414 cam shaft 416 link 418 gear
420 gear handle 422 rack 422a tooth shape part
424 bayonet 426 sleeve boss 428 pin
Detailed Description
A preferred embodiment of the reciprocating cutting tool of the present invention is a jigsaw. As shown in fig. 1, the left side of the jigsaw 1 of the present embodiment is defined as the rear side of the jigsaw 1, the right side is defined as the front side, the upper side is defined as the upper side, and the lower side is defined as the lower side. The jigsaw 1 has a reciprocating axis X extending in the up-down direction and a longitudinal housing axis Y extending in the forward-backward direction, the axes X and Y being perpendicular to each other.
Referring to fig. 1, the jigsaw 1 includes a housing 2, a power source, preferably a motor 4 in this embodiment, is fixedly disposed in the housing 2, the motor 4 is connected to and rotatably drives a main shaft 104, one end of the main shaft 104 is connected to the motor 4, and the other end forms a gear, which is engaged with the outer peripheral surface of a large gear 106. The gearwheel 106 is driven by the main shaft 104 to pivot about its own pivot axis. A drive shaft 108 is eccentrically arranged on the front end face of the gearwheel 106, which drive shaft 108 penetrates into a slide groove 110. The runner 110 is fixedly connected to the reciprocating rod 12 and extends in a direction perpendicular to both the axis X and the axis Y. The reciprocating lever 12 is movable in the directions of the axis X and the axis Y, and is fixed in the direction perpendicular to the axes X and Y. Thus, the rotational movement of the motor 4 is converted into the reciprocating movement of the slide groove 110 and the reciprocating lever 12 in the direction of the axis X by the main shaft 104, the large gear 106, and the driving shaft 108. The reciprocating bar 12 in turn drives a saw blade 14 provided at a lower end thereof to perform a reciprocating cutting action. The blade 14 has a cutting face at the front and a back face at the rear. The reciprocating bar 12 and the saw blade 14 are combined together and referred to as a reciprocating mechanism. The rear end face of the large gear 106 is eccentrically provided with a cutter lifting driving shaft 302, and the eccentric direction of the cutter lifting driving shaft 302 is opposite to that of the driving shaft 108. The cutter lifting drive shaft 302 is connected to a connecting plate 304 and drives it to reciprocate in the X-axis direction. A handle 6 is formed above the housing 2, and a switch 8 for controlling the motor 4 is arranged on the handle 6. A rotary handle 202 is provided at the upper front of the housing 2 of the jigsaw 1, the rotary handle 202 being pivotable relative to the housing about an axis X, the rotary handle 202 being connected to the reciprocating lever 12, rotation of which causes the reciprocating lever 12 and the saw blade 14 to rotate about the axis X.
As shown in fig. 2, an operating element 402 is pivotally connected to the housing 2 of the jigsaw 1, and the operating element 402 can effectively control the jigsaw 1 to be located in 5 shift positions and rotationally switched among five shift positions, which correspond to five operating states of the jigsaw 1, which are sequentially: the raising of the blade 0 position (shown as 0 position) as shown in fig. 8a, in which the jigsaw 1 cannot rotate and the blade cannot be raised; the lift blade I position (shown as position I) shown in fig. 8b, in which the jigsaw 1 cannot rotate, the lift blade amount is minimum; the blade raising position II (shown in position II) shown in fig. 8c, where the jigsaw 1 cannot rotate and the blade raising amount is centered; the blade raising position III (shown in position III) shown in fig. 8d, in which the jigsaw 1 cannot rotate, the blade raising amount is the maximum; when the jigsaw 1 is rotated by the rotation S-range (shown S-position) as shown in fig. 8e, it is not possible to raise the blade. When the operating element is switched to the cutter lifting 0 gear, the cutter lifting I gear, the cutter lifting II gear and the cutter lifting III gear, the jig saw 1 is in a cutter lifting support mode, and when the operating element is switched to the rotating S gear, the jig saw 1 is in a rotating mode. The mode of realization and the effects thereof are specifically described later.
As shown in fig. 3 and 4, a sleeve 204 extends from the lower part of the rotary handle 202, and the bottom of the sleeve 204 is provided with a cross-shaped hole 205 formed by overlapping a deep rectangular hole 221 and a shallow rectangular hole 222 and arranged along the direction of the axis X. A bearing bracket 206 (see fig. 1) is provided on the housing 2 below the sleeve 204, and a ball bearing 208 is mounted on the bearing bracket 206, and the ball bearing 208 is adapted to rotate on the bearing bracket 206 in all directions. The ball bearing 208 has a rectangular through hole 203, two symmetrical rectangular protrusions 210 are formed by extending two sides of the through hole 203, the upper end of the reciprocating rod 12 is provided with a rectangular end 13, and the rectangular end 13 is arranged in the through hole 203 of the ball bearing 208. The aforementioned deep rectangular hole 221 of the cross-shaped hole 205 partially receives the rectangular end 13 above the reciprocating lever 12, and the shallow rectangular hole 222 of the cross-shaped hole 205 partially receives the two bearing lugs 210 above the ball bearing 208. The deep rectangular hole 221 is of sufficient length to accommodate the reciprocating rod 12 and its upper rectangular end 13, which are inserted through the ball bearing 208, to move reciprocally along the axis X, but not to allow it to rotate about the axis X relative to the ball bearing 208. And the deep rectangular hole 221 has a portion slightly wider than the rectangular end 13 of the reciprocating lever 12 to allow the reciprocating lever 12 and the ball bearing 208 to swing slightly in a direction perpendicular to the axis X, allowing the blade 14 to perform a blade lifting action.
When the rotating handle 202 is pivoted, the sleeve 204 and the cross hole 205 at the bottom of the sleeve are driven to pivot, the ball bearing 208 and the bearing lug 210 on the ball bearing 208 arranged in the cross hole 205 and the reciprocating rod 12 and the rectangular end 13 on the reciprocating rod are simultaneously driven to rotate around the axis X, and then the ball bearing 208 and the reciprocating rod 12 and the saw blade 14 on the reciprocating rod are also driven to rotate.
When the operating element 402 is rotated to any one of the raising-knife 0, raising-knife I, raising-knife II, and raising-knife III, the jigsaw 1 is in the support raising mode in which the reciprocating lever 12 and the saw blade 14 can be subjected to a raising force in a direction perpendicular to the reciprocating direction of the saw blade 12. As previously described, the bushing 204 and ball bearing 208 allow for this blade lifting action.
As shown in fig. 3 and 5, a blade lifting component 303 is disposed in the housing 2, the blade lifting component 303 includes a connecting plate 304 and a blade lifting plate 308 disposed along the axis X direction, the blade lifting plate 308 is pivotally connected to the connecting plate 304 via a pin, the connecting plate 304 has an upper end and a lower end, the upper end is provided with a blade lifting groove 306 perpendicular to the axis X direction, the lower end is pivotally connected to a guide wheel limiting mechanism, in this embodiment, the guide wheel limiting mechanism is the blade lifting plate 308 which simultaneously functions as a blade lifting, the blade lifting plate 308 has a blade lifting end 310 and a blade lifting plate side 312 perpendicular to the blade lifting end 310, the blade lifting plate 308 is provided with a blade lifting plate torsion spring 309, and the blade lifting plate torsion spring 309 presses the blade lifting end 310 and the connecting plate 304 to be on the same axis.
As shown in fig. 3 and 5, an eccentric cutter lifting driving shaft 302 is disposed on a rear end surface of the large gear 106, and the cutter lifting driving shaft 302 is inserted into a cutter lifting groove 306 of the connecting plate 304 and can drive the connecting plate 304 and the cutter lifting plate 308 to reciprocate along the axis X.
As shown in fig. 3 and 7, an idler bracket 314 is provided at the lower end of the knife raising plate 308. Idler bracket 314 is connected to housing 2 by a pivot shaft 317 pivotally mounted to housing, and idler bracket 314 further includes a bracket top end 315 and a bracket bottom end 320 located on opposite sides of pivot shaft 317. The top end 315 of the holder has a flat surface and the bottom end 320 of the holder has a guide wheel 316 mounted thereon, the guide wheel 316 being located generally rearward of the blade 14. Idler yoke 314 and idler 316 combine to form what is referred to as a drive assembly. Idler yoke 314 is provided with a yoke torsion spring 318, which yoke torsion spring 318 urges the yoke top end 315 towards the lift end 310 of the lift plate 308, the yoke bottom end 320 and the idler 318 away from the blade 14.
As shown in fig. 3, when the lifting drive shaft 302 (see fig. 1) drives the connecting plate 304 to move downward, the saw blade 14 is driven by the drive shaft 108 to perform a cutting action upward via the reciprocating rod 12, and the connecting plate 304 drives the lifting plate 308 and the lifting end 310 thereof to move downward, the lifting end 310 abuts against the holder top end 315 and pushes the guide wheel holder 314 to rotate around the pivot shaft 317 against the force of the holder torsion spring 318, so that the holder top end 315 moves downward along the X-axis direction, the holder bottom end 320 and the guide wheel 316 move forward along the Y-axis direction, the saw blade 14 and the reciprocating rod 12 are pushed forward along the Y-axis direction with the ball bearing 208 as the pivot axis, and the saw blade 14 obtains a lifting force for facilitating cutting, and the jigsaw 1 is in the lifting support mode. As lift blade drive shaft 302 moves attachment plate 304 in the X-axis direction, idler yoke 314 returns to its original position under the urging of yoke torsion spring 318.
When the reciprocating bar 12 and the saw blade 14 perform a cutting and return motion, the idler yoke 314 and the idler 316 also perform a knife lifting and return motion. In the above-described blade lifting and returning operation, the blade lifting end 310 of the blade lifting plate 308 has an uppermost position and a lowermost position on the axis X.
The conversion of the jigsaw 1 between the above-described rotation mode and the blade support mode is described in detail below.
Referring to fig. 3 and 6, another idler limiting mechanism, in this embodiment a cam 404, is mounted on a side of the operating element 402 located inside the housing 2, and the cam 404 is located above the bracket top 315 of the idler bracket 314 and adapted to be driven by the operating element 402 to rotate around the pivot axis of the cam 404. Cam 404 has a base 413 to which operating member 402 is attached, a cam shaft 414 extending from base 413, and a cam plate 411 attached to base 413. The base 413 is substantially circular, and the outer side of the cam disc 411 is formed by connecting an arc-shaped high-level surface 412, a planar high-level surface 410, a high-level surface 408 and a high-level surface 406 in sequence, and the distances from the high-level surfaces to the pivot axis of the cam 404 are gradually reduced. The inner side of the cam disc 411 is a circular arc surface 407, and the outer side surface and the inner side surface of the cam disc 411 are connected through two symmetrically arranged low-level surfaces 409. The two low surfaces 409 are located in a plane that passes through the pivot axis of the cam 404.
As previously discussed, a bracket torsion spring 318 on idler bracket 314 always urges idler bracket 314 to pivot about its own pivot point, moving an idler 316 thereon away from blade 14, and a bracket top 315 of idler bracket 314 proximate cam 404. The blade lifting end 310 of the blade lifting plate 308 has an uppermost position and a lowermost position in the direction of the axis X, and when the operating element 402 is switched to the blade lifting 0, blade lifting I, blade lifting II, and blade lifting III, respectively, the operating element pivots the cam 404 to face the upper surface 412, the upper surface 410, the upper surface 408, and the upper surface 406, respectively, to the bracket top 315. When the high surfaces respectively face the bracket top end 315, the high surface 412 is located below the lowest position of the cutter lifting end 310; the raised surface 410, the raised surface 408, and the raised surface 406 are each located between the uppermost position and the lowermost position of the blade lifting end 310. Thus, when the elevation surface 412 faces the holder tip 315, the holder tip 315 is limited to the lowest point of the elevation surface 412 in the X-direction and is located below the lowest point of the blade raising plate 308, i.e., the blade raising end 310 cannot contact the holder tip 315. When the cam 404 pivots, the high level surface 410, the high level surface 408 and the high level surface 406 face the bracket top end 315, the bracket top end 315 gradually rises due to the gradual approach of the cam 404 to the pivot point, and is higher than the lowest position of the cutter lifting plate 308 and lower than the highest position of the cutter lifting plate 308, so that the cutter lifting action of the cutter lifting plate 308 acts on the guide wheel 316, the acting stroke is sequentially increased, and the cutter lifting amount is sequentially increased.
As the bracket tip 315 gradually rises, the guide wheel 316 also gradually moves back away from the blade 14. However, when the jigsaw 1 operates in the raising support mode, the blade 14 is subjected to a reaction force from the workpiece, and the blade 14 and the reciprocating lever 12 pivot about the ball bearing 308 as a pivot point, always following the guide wheel 316.
When the jigsaw 1 is in the lift support mode described above, the rotational function of the jigsaw 1 is inhibited, as described below.
As shown in fig. 3, one end of the cam handle 414 is connected to the cam 404, the other end is pivotally connected to one end of a link 416, and the other end of the link 416 is pivotally connected to a gear handle 420 that is pivotally connected to a sector gear 418 provided on the housing 2, so that when the operating element 402 is rotated, the sector gear 418 is pivoted by the cam 404 and the link 416. A rotary lock, in this embodiment a rack 422, is disposed adjacent to the sector gear 418 for engagement therewith. The rack 422 is located on the housing 2 and is adapted to move back and forth along the axis X. The rack 422 has a U-shaped bayonet 424 at the top end and a tooth-shaped portion 422a at the end.
Meanwhile, the outer side of the sleeve 204 of the rotating handle 202 is correspondingly provided with a snap-in part, in this embodiment, a sleeve projection 426, which is matched with the U-shaped bayonet 424. The sleeve projection 426 is positioned such that the U-shaped notch 424 catches the sleeve projection 426 only when the cutting face of the saw blade 14 is facing forward of the axis Y.
When the operating element 402 pivots the cam 404 and switches between the blade raising 0, the blade raising I, the blade raising II and the blade raising III, the sector gear 418 is simultaneously pivoted but is not engaged with the tooth-shaped portion 422a of the rack 422, and the U-shaped bayonet 424 of the rack 422 is always caught by the sleeve protrusion 426, so that the reciprocating lever 12 cannot rotate. Only when the operating element 402 pivots the cam 404 to switch from the lifting-cutter III-position to the rotating-cutter S-position, the gear 418 engages the rack 422 and moves the rack 422 downward along the axis X, the U-shaped notch 424 of the rack 422 disengages from the sleeve projection 426, the jigsaw 1 is switched to the rotating mode, and the rotating handle 202 pivots the reciprocating lever 12 and the saw blade 14 about the axis X. Conversely, when the operating element 402 is switched from the rotational S-range to the lifting-blade III-range, the gear 418 engages the rack 422 and drives the rack 422 upward along the axis X, the U-shaped bayonet 424 of the rack 422 catches the sleeve-pipe protrusion 426, and the jigsaw 1 is switched to the lifting-blade support mode.
It should be noted that: due to the specially designed position of the sleeve projection 426, when the cutting surface of the saw blade 14 deviates from the front of the housing 2 of the jigsaw 1, the U-shaped notch 424 of the rack 422 cannot catch the sleeve projection 426, and the operating element 402 cannot be shifted from the S-position rotation to the III-position lifting. In this embodiment, the rotation knob 402 preferably has an indicator arrow thereon to assist the user in determining whether the blade 14 is facing forward of the housing 2 of the jigsaw 1.
Under the support mode of the cutter lifting, the two guide wheel limiting mechanisms are as follows: the blade lifting end 310 and the cam 404 are both in a support position which presses the bracket top 315 of the guide bracket 314 to position the guide at a distance which is accessible for pivoting the blade 14 about the ball bearing 208 in a plane defined by the intersection of the axis X and the axis Y, and the jigsaw 1 operates with a workpiece which exerts a reaction force on the blade 14 to bring the guide 14 and the blade into close abutment, thereby restricting rotation of the blade 14 about the axis X. When the jig saw 1 is switched from the cutter lifting support mode to the rotation mode, the two guide wheel limiting mechanisms are as follows: the blade lifting end 310 and the cam 404 are both in a released position in which they move upwardly in the direction of axis X and no longer press the bracket tip 315 to locate the guide wheel a distance up to which the blade 14 can pivot about the ball bearing 208 in a plane defined by the intersection of axis X and axis Y. The raising function is simultaneously disabled and the idler wheel is moved away from the blade 14 beyond the distance that the blade 14 can pivot about the ball bearing 208 in a plane defined by the intersection of the axis X and the axis Y, as described below.
As shown in fig. 3, a lever, in this embodiment a pin 428, is provided at the connection point of the link 416 and the cam handle 414, when the operating element 402 is switched from the lift-blade III position to the rotational S position, the cam 404 pivots, the pin 428 moves upward along with the cam handle 414, abuts against the side 312 of the lift-blade plate and overcomes the force of the lift-blade torsion spring 309, and the lift-blade plate 308 pivots, so that the lift-blade end 310 moves upward in the direction of the axis X, away from the bracket top end 315 of the idler bracket 314, and forms an angle smaller than 180 degrees with the connection plate. Thus, although the connecting plate 304 of the blade lifting member 303 is still driven by the motor to reciprocate in the direction of the axis X, the blade lifting end 310 no longer abuts against the holder top end 315 and presses the holder bottom end 320 and the guide wheel 316 thereon to engage with the saw blade 14, and no longer has the highest position and the lowest position in the direction of the axis X, and the blade lifting function is disabled. At the same time, cam 404 is flipped over so that low surface 409 faces holder top 315 and no longer abuts holder top 315 and forces holder bottom 320 and its guide wheels 316 against saw blade 14. Thus, the two guide wheel limiting mechanisms are moved away from the positions where the two guide wheel limiting mechanisms play a limiting role. Without limitation, idler yoke 314 pivots significantly under yoke torsion spring 318, and yoke base end 320 and idler 316 move rearward along axis Y away from the distance that blade 14 can pivot about ball bearing 208 in the plane defined by the intersection of axis X and axis Y, and no longer contact blade 14. The blade 14 is therefore not constrained from pivoting about the axis X by the guide 316.
Conversely, when the operating member 402 is shifted from the S-position to the III-position, the operating member 402 causes the cam 404 to pivot the idler yoke 314 against the force of the yoke torsion spring 318, the idler 316 moves closer to the blade 14, and the pin 428 moves away from the blade side 312, and the blade 308 returns to the blade-lifting operating position under the action of the blade torsion spring 309.
The following generally describes the conversion process of the jig saw 1 between the blade raising 0, the blade raising I, the blade raising II, the blade raising III and the rotation S.
8 a-8 e, when operating member 402 is in the lift-blade 0 position, raised surface d412 faces carriage top end 315 of idler carriage 314, and carriage top end 315 is below the lowest position of lift plate 308; the U-shaped bayonet 424 of the rack 422 catches the sleeve lug 426, the gear 418 does not engage the rack 422, the pin 428 does not contact the side 312 of the blade raising plate, and the jigsaw 1 cannot rotate or raise the blade. The operating element 402 is switched from the cutter lifting 0 gear to the cutter lifting I gear, the high level surface 410 faces the bracket top end 315, and the bracket top end 315 is higher than the lowest position of the cutter lifting plate 308 and lower than the highest position of the cutter lifting plate 308; the U-shaped bayonet 424 of the rack 422 is clamped in the sleeve boss 426, the gear 418 is not meshed with the rack 422, the pin 428 is not contacted with the side edge 312 of the cutter lifting plate, the curve saw 1 cannot rotate, and the cutter lifting amount is small. The operating element 402 is switched from the lifting blade I position to the lifting blade II position, the high-level surface 408 faces the bracket top end 315, and the bracket top end 315 is higher than the lowest position of the lifting blade plate 308 and lower than the highest position of the lifting blade plate 308; the U-shaped bayonet 424 of the rack 422 clamps the sleeve bump 426, the gear 418 does not engage with the rack 422, the pin 428 does not contact with the side edge 312 of the knife lifting plate, the jigsaw 1 cannot rotate, and the knife lifting amount is centered. The operating element 402 is switched from the lifting blade II position to the lifting blade III position, the high-level surface 406 faces the bracket top end 315, and the bracket top end 315 is higher than the lowest position of the lifting blade plate 308 and lower than the highest position of the lifting blade plate 308; the U-shaped bayonet 424 of the rack 422 is used for clamping the sleeve boss 426, the gear 418 is not meshed with the rack 422, the pin 428 is not contacted with the side edge 312 of the cutter lifting plate, the curve saw 1 cannot rotate, and the cutter lifting amount is maximum. The operating member 402 is switched from the lifting-cutter III-position to the rotating S-position, the cam 404 is turned over, the lower surface 409 faces the top end 315 of the support, the pin 428 biases the lifting plate 308 via the side 312 of the lifting plate, the guide wheel 316 is retracted away from the saw blade 14, the gear 418 engages the rack 422 and drives the rack 418 to move downward, the U-shaped bayonet 424 of the rack 422 is disengaged from the sleeve boss 426, and the jigsaw 1 can rotate and cannot lift the cutter.
Conversely, the operation element 402 can be adjusted from the rotation S-range to the cutter lifting 0-range in sequence, and the detailed process is not described again.
There are numerous specific embodiments of the invention. All technical solutions formed by using equivalent substitutions or equivalent transformations fall within the scope of the claimed invention.