CN210100066U

CN210100066U - Art designing knife

Info

Publication number: CN210100066U
Application number: CN201920375872.4U
Authority: CN
Inventors: 徐永升
Original assignee: Deli Group Co Ltd
Current assignee: Deli Group Co Ltd
Priority date: 2019-03-22
Filing date: 2019-03-22
Publication date: 2020-02-21
Anticipated expiration: 2029-03-22

Abstract

The utility model discloses an art knife, which comprises a knife shell, a blade and an adjusting button, wherein the blade is arranged in the knife shell, the adjusting button is arranged on the knife shell, and also comprises a blade bracket, a tail cover and a tail cover button arranged on the tail cover, the tail cover is arranged at the tail part of the knife shell, the blade support is arranged in the knife shell, the blade is arranged on the blade support, the tail part of the blade bracket can extend into the tail cover, a locking mechanism is arranged between the tail cover and the blade bracket, the locking mechanism can be unlocked when the tail button is pressed down, the tail part of the blade bracket is separated from the tail cover when the locking mechanism is unlocked, blade support head can slide toward the shell head when adjustment button promotes, the blade when afterbody button is pressed down and promote adjustment button toward the shell head motion, the utility model provides an art knife that factor of safety is high.

Description

Art designing knife

Technical Field

The utility model relates to an office supplies technical field especially relates to an art designing knife.

Background

The art designing knife is also commonly called as a graver or a wallpaper knife, is a knife for art and handicraft, is mainly used for cutting objects with soft texture, mainly consists of a knife handle and a blade and is of a pull-out structure. The blade is mostly the bevel connection, can be in the same direction as the marking off rupture of piece body with the blunt, new blade point appears, facilitates the use, according to prior art, because the art designing blade is sharp, and easily release the blade, if the adult places improperly, kids play as the toy, will cut oneself unintentionally, and occurrence tragedy, factor of safety is low.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem that will solve is: overcomes the defects of the prior art and provides the art knife with high safety factor.

The utility model adopts the technical proposal that: the utility model provides an art knife, includes sword shell, blade and adjustment button, the blade establish in the sword shell, adjustment button establish on the sword shell, it still includes blade support, tail lid and establishes the tail-hood button on the tail lid, the tail lid establish at the sword shell afterbody, the blade support establish in the sword shell, the blade establish at the blade support, blade support afterbody can stretch into in the tail lid, tail lid and blade support between be equipped with locking mechanical system, locking mechanical system can unblock when the tail-hood button is pressed, blade support afterbody break away from with the tail lid when locking mechanical system unblock, blade support head can slide toward the sword shell head when adjustment button promotes, the blade move toward the sword shell head when the tail-hood button is pressed and promote adjustment button.

After the structure more than adopting, compared with the prior art, the utility model has the following advantage: the structure is characterized in that a blade support, a tail cover and a tail cover button are arranged, a blade is arranged at the head of the blade support, a locking mechanism is arranged in the tail cover, and the tail of the blade support can be locked in the tail cover; when the blade is pushed out, the blade can be pushed out by simultaneously operating two hands, the tail cover button enables the blade support to be separated from the locking mechanism and pushes the adjusting button to push the blade to move, the blade cannot be pushed out by operating with one hand, and the safety of the art designing knife is greatly improved. Compared with a common art knife, the structure has a locking function and is automatically locked, the situation that locking is forgotten when the blade is retracted is avoided, and the safety factor is high.

Preferably, the locking mechanism is that the tail of the blade support is provided with an elastic part, the upper surface of one end of the elastic part close to the tail cover is provided with a clamping protrusion, the tail cover is internally provided with a cavity, the top of the cavity is provided with a baffle, the baffle is distributed along the width direction of the cutter shell, the clamping protrusion abuts against the surface of the baffle far away from the blade when the elastic part extends into the cavity, the upper surface of the tail cover is provided with a groove, the bottom of the groove is provided with a through hole communicated with the cavity, the bottom of the tail cover button is provided with a pressing protrusion, the tail cover button is arranged in the groove, the pressing protrusion extends into the cavity through the through hole, the pressing protrusion abuts against the baffle and is positioned above the clamping protrusion when the clamping protrusion abuts against the surface far away from the blade, the elastic part tilts upwards under a free state, and the clamping protrusion abuts against the baffle when the elastic part of the blade support moves towards the tail cover, the locking of elastic component has been realized, and the tail-hood button is established on the tail-hood, utilizes the protruding arch of pressing of tail-hood button to press down the joint arch and make the joint arch break away from the baffle, and adjustment button just can drive the blade toward the motion of shell head like this, simple structure, and the reliability is high.

Preferably, a spring is arranged in the groove, the spring is sleeved on the pressing protrusion, the tail cover button can automatically reset after being pressed down, and the use is convenient.

Preferably, the top in the cavity be equipped with the ascending support of opening, the shape of support cross section be "Contraband" font, the through-hole establish the bottom at the support, tail-hood button run through tail-hood upper end sliding fit in the support, the circumference of tail-hood button lateral surface on be equipped with two at least spacing archs, spacing arch support the top at the cavity when tail-hood button up-moves, the baffle establish the lower surface at the support, establish the support, tail-hood button sliding fit is on the support, establish spacing arch simultaneously, prevent that the tail-hood button from breaking away from the recess, the reliability is high.

Preferably, the limiting protrusions are uniformly distributed on the circumference of the outer side surface of the tail cover button, and the limiting effect is good.

Preferably, the lower extreme of the baffle one side of nearly blade be equipped with first inclined plane, the protruding upper surface of joint be equipped with first inclined plane complex second inclined plane, play the guide effect, the protruding second inclined plane of joint and the cooperation of first inclined plane are convenient for the joint arch and are inserted the cavity.

Preferably, the second inclined plane on be equipped with the constant head tank, protruding lower extreme of pressing block in the constant head tank when the joint is protruding to lean on the surface that keeps away from the blade at the baffle, it is protruding to be convenient for press the arch can accurately press the joint, prevent to skid, the reliability is high.

Preferably, the knife shell is internally provided with sliding chutes which are distributed along the length direction of the knife shell, the sliding groove respectively penetrates through the head part and the tail part of the knife shell, the blade support and the blade are both in sliding fit in the sliding groove, square wave-shaped grooves are arranged on both sides of the upper end of the sliding groove, a mounting bulge for mounting the tail part of the blade is arranged on the upper surface of the head part of the blade bracket, the blade bracket is also provided with clamping grooves which are distributed along the width direction of the sliding groove, elastic sheets are arranged in the clamping grooves, the spring plate can be clamped in the square wave-shaped groove in a free state, the lower end of the adjusting button is abutted against the upper surface of the spring plate, the spring plate is downwards pressed by the adjusting button to be separated from the square wave-shaped groove, the square wave-shaped groove is a square wave in the shape of the cross section, the spring plate is located in the clamping groove, and the adjusting button is pressed on the spring plate to enable the spring plate to slide up and down in the clamping groove, so that the spring plate is clamped in the square wave-shaped groove or separated from the square wave-shaped groove.

Preferably, an inner cutter shell is arranged in the cutter shell, and the sliding groove and the square wave-shaped groove are both arranged in the inner cutter shell, so that the cutter is convenient to install and replace.

Preferably, the upper surface of the blade support is provided with two guide bulges respectively, the guide bulges are distributed along the length direction of the sliding groove, the side surfaces, far away from the center of the blade support, of the guide bulges are in sliding fit with the side surfaces of the square wave-shaped groove, the two ends of the clamping groove respectively penetrate through the guide bulges to play a role in guiding, and the blade support is more stable in the sliding process of the sliding groove.

As preferred, the blade support on still be equipped with the bar groove, the bar groove respectively along sword shell length direction, bar groove bottom both ends all be equipped with the open slot around, the shell fragment include arch-shaped plate and elastic plate, arch-shaped plate axis be parallel to each other or on same straight line with the draw-in groove axis, the elastic plate establish respectively in the left and right sides of arch-shaped plate, the elastic plate stretch into respectively in the open slot and the elastic plate sliding fit is respectively in the open slot, the adjustment button lower extreme be equipped with the arc wall, the upper end card of arch-shaped plate in the arc wall, the shell fragment divide into arch-shaped plate and elastic plate, the shape of cross section of arch-shaped plate is the arch, the arch-shaped plate is established in the draw-in groove, the elastic plate is located the bar inslot, the both ends of elastic plate all stretch into corresponding open slot, through adjustment button's lower extreme extrusion arch-shaped plate, the arch-shaped plate breaks, the elastic plate stretches into the open slot, the hand is loosened, the elasticity of the elastic plate is relied on to enable the arch plate to move upwards and to be clamped in the square wave groove, the elastic plate is always located in the open slot, the elastic piece is guaranteed not to run out of the strip-shaped groove, and the reliability is high.

As preferred, the bar groove run through blade holder downwards, blade holder basal surface be equipped with the dog, the dog be located the front and back both ends in bar groove respectively, the open slot establish on the dog, do not account for the space, light in weight, the operation of being convenient for guarantees that the both ends of elastic plate are located the open slot all the time.

Drawings

Fig. 1 is a schematic front view of an art knife of the present invention;

FIG. 2 is an enlarged schematic view of A of FIG. 1;

fig. 3 is a top view of the utility knife;

FIG. 4 is a perspective view of a tail cover of the utility knife;

FIG. 5 is a perspective view of the utility model with the knife shell and the tail cover removed;

FIG. 6 is a perspective view of a utility knife blade holder of the present invention;

FIG. 7 is a perspective view of a blade holder and a tail cap button of the utility model;

fig. 8 is a perspective view of the utility knife elastic sheet.

The knife comprises a knife shell 1, a knife shell 2, a knife blade 3, an adjusting button 4, a knife blade support 5, a tail cover 6, a tail cover button 7, an elastic piece 8, a clamping protrusion 9, a through hole 10, a cavity 11, a baffle plate 12, a pressing protrusion 13, a support 14, a limiting protrusion 15, a first inclined surface 16, a second inclined surface 17, a sliding groove 18, a square wave groove 19, a clamping groove 20, a spring plate 21, an inner knife shell 22, a guide protrusion 23, a strip groove 24, an open groove 25, an arch plate 26, an elastic plate 27, an arc groove 28, a stop block 29, a positioning groove 30, a groove 31 and an installation protrusion.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and the following detailed description.

As shown in the figure, the utility model provides an art knife, which comprises a knife shell 1, a blade 2 and an adjusting button 3, wherein the blade 2 is arranged in the knife shell 1, the adjusting button 3 is arranged on the knife shell 1, the art knife also comprises a blade support 4, a tail cover 5 and a tail cover button 6 arranged on the tail cover 5, the tail cover 5 is arranged at the tail part of the knife shell 1, the blade support 4 is arranged in the knife shell 1, the tail part of the blade 2 is arranged at the head part of the blade support 4, the tail part of the blade support 4 can extend into the tail cover 5, a locking mechanism is arranged between the tail cover 5 and the blade support 4, the locking mechanism can be unlocked when the tail cover button 6 is pressed, the tail part of the blade support 4 is separated from the tail cover 5 when the locking mechanism is unlocked, the head part of the blade support 4 can slide towards the head part of the knife shell 1 when the adjusting button 3 is pushed, the blade 2 moves towards the head part of the knife shell 1 when the tail cover button 6 is pressed and the adjusting button 3 is pushed, the utility model has the advantages that the blade support 4, the tail cover 5 and the tail cover button 6 are arranged, the blade 2 is arranged at the head of the blade support 4, the locking mechanism is arranged in the tail cover 5, and the tail of the blade support 4 can be locked in the tail cover 5, when the blade 2 is withdrawn, the tail of the blade support 4 is locked by the locking mechanism and can be automatically locked; when the blade 2 is pushed out, the blade 2 can be pushed out by simultaneously operating two hands, the tail cover button 6 enables the blade support 4 to be separated from the locking mechanism, meanwhile, the adjusting button 3 is pressed down to push the blade 2 to move, the blade cannot be pushed out by single-hand operation, and the safety of the art designing knife is greatly improved. For ordinary art designer's sword, this structure area locking function, and for automatic locking, when having avoided withdrawing blade 2, forget the condition of pinning, factor of safety is high.

The locking mechanism is characterized in that an elastic part 7 is arranged at the tail part of the blade support 4, a clamping bulge 8 is arranged on the upper surface of one end, close to the tail cover 5, of the elastic part 7, a cavity 10 is arranged in the tail cover 5, a baffle 11 is arranged at the top of the cavity 10, the baffle 11 is distributed along the width direction of the blade shell 1, the clamping bulge 8 abuts against the surface, far away from the blade 2, of the baffle 11 when the elastic part 7 extends into the cavity 10, a groove 30 is arranged on the upper surface of the tail cover 5, a through hole 9 communicated with the cavity 10 is arranged at the bottom of the groove 30, a pressing bulge 12 is arranged at the bottom of the tail cover button 6, the tail cover button 6 is arranged in the groove 30, the pressing bulge 12 extends into the cavity 10 through the through hole 9, and the pressing bulge 12 is positioned above the clamping bulge 8 when the clamping bulge 8 abuts against the surface, far away from the blade 2, elastic component 7 perks up under free state, the protruding 8 of joint can support and lean on baffle 11 when the elastic component 7 of blade holder 4 removes toward the tail-hood 5 in, the locking of elastic component 7 has been realized, tail-hood button 6 is established on tail-hood 5, utilize the protruding 12 pairs of protruding 8 of joint of pressing of tail-hood button 6 to press and make the protruding 8 of joint break away from baffle 11, adjustment button 3 just can drive blade 2 toward the motion of 1 head of sword shell like this, moreover, the steam generator is simple in structure, and the reliability is high.

The groove 30 is internally provided with a spring which is sleeved on the pressing bulge 12, and the tail cover button 6 can automatically reset after being pressed down, so that the use is convenient.

Cavity 10 in the top be equipped with the ascending support 13 of opening, the shape of support 13 cross section be "Contraband" font, through-hole 9 establish the bottom at support 13, tail-hood button 6 run through tail-hood 5 upper end sliding fit in support 13, the circumference of tail-hood button 6 lateral surface on be equipped with two at least spacing archs 14, spacing arch 14 support the top that leans on at cavity 10 when tail-hood button 6 up moves, baffle 11 establish the lower surface at support 13, establish support 13, tail-hood button 6 sliding fit is on support 13, establishes spacing arch 14 simultaneously, prevents that tail-hood button 6 from breaking away from recess 30, the reliability is high.

The limiting protrusions 14 are uniformly distributed on the circumference of the outer side surface of the tail cover button 6, and the limiting effect is good.

The lower extreme of the baffle 11 one side that is close to blade 2 be equipped with first inclined plane 15, protruding 8 upper surfaces of joint be equipped with first inclined plane 15 inclined plane complex second inclined plane 16, play the guide effect, protruding 8 second inclined plane 16 of joint and first inclined plane 15 cooperation are convenient for protruding 8 insertions cavity 10 of joint.

Second inclined plane 16 on be equipped with constant head tank 29, protruding 12 lower extreme of pressing block in constant head tank 29 when protruding 8 of joint support leans on the surface that keeps away from blade 2 at baffle 11, be convenient for press protruding 12 can accurately press the protruding 8 of joint, prevent to skid, the reliability is high.

The utility model discloses a knife blade, including a knife shell 1, a knife blade support 4, a knife blade 2, a spring plate 20, a knife blade groove 18, a regulating button 3, a sliding groove 17, a blade support 17, a blade 2, a square wave groove 18, a mounting protrusion 31 for mounting the tail of the knife blade 2, a clamping groove 19, a spring plate 20, a square wave groove 18, a clamping groove 19, a spring plate 20, a regulating button 3, a square wave groove 18, a square wave groove 19, a sliding groove 17, a blade support 4, a blade 2, a blade support 4, a blade support and a blade support, wherein the sliding groove 19 is in the length direction of the knife shell 1, the sliding groove 17 is arranged on the upper end of the blade support, the spring plate 20 is arranged in the width direction of the, the adjusting button 3 is pressed on the elastic sheet 20 to slide up and down in the clamping groove 19, so that the elastic sheet 20 is clamped in the square wave-shaped groove 18 or separated from the square wave-shaped groove 18.

The utility model discloses a cutter shell, including sword shell 1, spout 17 and square wave form groove 18, the sword shell 21 is equipped with interior sword shell 21 in, be convenient for install and change.

Blade support 4 upper surface be equipped with two direction arch 22 respectively, direction arch 22 distribute along spout 17 length direction, direction arch 22 keep away from the side at blade support 4 center all with the side sliding fit of square wave form groove 18, draw-in groove 19 both ends run through direction arch 22 respectively, play the guide effect, blade support 4 is more steady at spout 17 slip in-process.

Blade support 4 on still be equipped with bar groove 23, bar groove 23 respectively along 1 length direction of sword shell, bar groove 23 bottom both ends all be equipped with open slot 24 around both ends, shell fragment 20 include arch-shaped plate 25 and elastic plate 26, arch-shaped plate 25 axis and draw-in groove 19 axis be parallel to each other or on same straight line, elastic plate 26 establish respectively in the left and right sides of arch-shaped plate 25, elastic plate 26 stretch into respectively in open slot 24 and elastic plate 26 respectively sliding fit in open slot 24, adjustment button 3 lower extreme be equipped with arc wall 27, the upper end card of arch-shaped plate 25 in arc wall 27, shell fragment 20 divide into arch-shaped plate 25 and elastic plate 26, the cross sectional shape of arch-shaped plate 25 is the arch, arch-shaped plate 25 establishes in draw-in groove 19, elastic plate 26 is located bar groove 23, the both ends of elastic plate 26 all stretch into corresponding open slot 24, through adjustment button 3's lower extreme extrusion arch plate 25, arch plate 25 breaks away from square wave groove 18, and elastic plate 26 stretches in open slot 24, and the hand loosens, relies on elastic plate 26's elasticity to make arch plate 25 up move the card in square wave groove 18, and elastic plate 26 is located open slot 24 all the time, guarantees that shell fragment 20 can not run out strip groove 23, and the reliability is high.

The bar groove 23 downwards run through

blade holder

4, 4 basal surfaces of blade holder be equipped with dog 28, dog 28 be located bar groove 23 both ends around respectively, open slot 24 establish on dog 28, do not account for the space, light in weight, the operation of being convenient for guarantees that the both ends of elastic plate 26 are located open slot 24 all the time.

Particularly, the utility model has the principle that the blade support 4, the tail cover 5 and the tail cover button 6 are arranged, the blade 2 is arranged at the head of the blade support 4, the tail cover 5 is internally provided with the locking mechanism, and the tail part of the blade support 4 can be locked in the tail cover 5; when the blade 2 is pushed out, the blade 2 can be pushed out by simultaneously operating two hands, the tail cover button 6 enables the blade support 4 to be separated from the locking mechanism, meanwhile, the adjusting button 3 is pressed down to push the blade 2 to move, the blade cannot be pushed out by single-hand operation, and the safety of the art designing knife is greatly improved. Compared with the common art knife, the structure has the locking function, is automatically locked, avoids the situation that the locking is forgotten when the blade 2 is retracted, has high safety factor, the prior art is that the upper end of the sliding groove 17 is provided with a rectangular groove, the structure is provided with a square wave groove 18, when the blade 2 is pushed out, the tail cover button 6 is pressed by a left hand, the tail cover button 6 presses the clamping bulge 8 downwards, the left hand is not loose, the clamping bulge 8 is separated from the baffle 11 at the moment, until the clamping bulge 8 moves to the lower part of the baffle 11, the adjusting button 3 is pushed by a right hand, the adjusting button 3 presses the elastic sheet 20, the right hand is not loose, the elastic sheet 20 is separated from the square wave groove 18 at the moment, until the elastic sheet 20 moves to the lower part of the square wave groove 18, then the adjusting button 3 is continuously pushed to the head part of the knife shell 1, the blade support 4 drives the blade 2 to move, when the clamping bulge 8 moves to the front part of, the length of the blade 2 extending out of the blade shell 1 is adjusted by the right hand, when the blade 2 stops, the right hand is released, and the elastic sheet 20 drives the arch-shaped plate 25 to move upwards to be clamped in the square wave-shaped groove 18 due to the elasticity of the elastic sheet, so that positioning is realized; when withdrawing blade 2, with the reverse adjustment button 3 that promotes of right hand, adjustment button 3 pushes down shell fragment 20, the right hand is not loose the hand, shell fragment 20 breaks away from square wave form groove 18 this moment, until the below of square wave form groove 18 is moved to shell fragment 20, then continue to promote adjustment button 3 and move toward the sword shell 1 in, blade support 4 drives blade 2 motion, second inclined plane and the protruding 8 entering cavity 10 of first inclined plane cooperation joint when the protruding 8 motion of joint is to baffle 11 with the front, until the protruding 8 motion of joint is to the baffle 11 at the back, because elastic component 7 itself has elasticity, elastic component 7 drives the protruding 8 upward movements of joint and supports the one side of leaning on at baffle 11 and keeping away from blade 2, realize the locking of blade 2, the in-process automatic locking of withdrawing at blade 2.

While the above is directed to the preferred embodiment of the present invention, it is not intended that it be limited, except as by the appended claims. The present invention is not limited to the above embodiments, and the specific structure thereof allows for changes, all the changes made within the protection scope of the independent claims of the present invention are within the protection scope of the present invention.

Claims

1. The utility model provides an art knife, includes sword shell (1), blade (2) and adjustment button (3), adjustment button (3) establish on sword shell (1), its characterized in that: it also comprises a blade bracket (4), a tail cover (5) and a tail cover button (6) arranged on the tail cover (5), the tail cover (5) is arranged at the tail part of the knife shell (1), the blade support (4) is arranged in the knife shell (1), the blade (2) is arranged on the blade bracket (4), the tail part of the blade bracket (4) can extend into the tail cover (5), a locking mechanism is arranged between the tail cover (5) and the blade bracket (4), the locking mechanism can be unlocked when the tail cover button (6) is pressed down, the tail part of the blade bracket (4) is separated from the tail cover (5) when the locking mechanism is unlocked, the head of the blade bracket (4) can slide towards the head of the knife shell (1) when the adjusting button (3) is pushed, the blade (2) moves towards the head of the knife shell (1) when the tail cover button (6) is pressed and the adjusting button (3) is pushed.

2. An art knife according to claim 1, wherein: the locking mechanism is characterized in that an elastic piece (7) is arranged at the tail of the blade support (4), a baffle (11) is arranged at the top of the cavity (10), a clamping protrusion (8) is arranged on the upper surface of one end, close to the tail cover (5), of the elastic piece (7), the baffle (11) is distributed along the width direction of the knife shell (1), the clamping protrusion (8) abuts against the surface, far away from the blade (2) by the baffle (11) when the elastic piece (7) extends into the cavity (10), a groove (30) is arranged on the upper surface of the tail cover (5), a through hole (9) communicated with the cavity (10) is formed in the bottom of the groove (30), a pressing protrusion (12) is arranged at the bottom of the tail cover button (6), the tail cover button (6) is arranged in the groove (30), the pressing protrusion (12) extends into the cavity (10) through the through hole (9), pressing protrusion (12) when joint protrusion (8) lean on and lean on the surface of keeping away from blade (2) at baffle (11) be located the protruding (8) top of joint.

3. An art knife according to claim 2, wherein: the groove (30) is internally provided with a spring which is sleeved on the pressing bulge (12).

4. An art knife according to claim 2, wherein: cavity (10) in the top be equipped with opening ascending support (13), support (13) cross section the shape be "Contraband" font, through-hole (9) establish the bottom at support (13), tail-hood button (6) run through tail-hood (5) upper end sliding fit in support (13), the circumference of tail-hood button (6) lateral surface on be equipped with two at least spacing arch (14), spacing arch (14) support when tail-hood button (6) up-motion and lean on the top at cavity (10).

5. An art knife according to claim 2, wherein: the lower extreme of baffle (11) one side of nearly blade (2) be equipped with first inclined plane (15), protruding (8) upper surface of joint be equipped with first inclined plane (15) inclined plane complex second inclined plane (16).

6. An art knife according to claim 1, wherein: the utility model discloses a knife blade, including sword shell (1) in be equipped with spout (17), spout (17) distribute along sword shell (1) length direction, spout (17) run through sword shell (1) head and afterbody respectively, blade support (4) and blade (2) all sliding fit in spout (17), both sides of spout (17) upper end all be equipped with square wave form groove (18), blade support (4) head upper surface be equipped with be used for blade (2) afterbody installation protruding (31), blade support (4) still be equipped with draw-in groove (19), draw-in groove (19) distribute along spout (17) width direction, draw-in groove (19) in be equipped with shell fragment (20), shell fragment (20) can block in square wave form groove (18) under free state, adjustment button (3) lower extreme support and lean on shell fragment (20) upper surface, the elastic sheet (20) is separated from the square wave-shaped groove (18) when the adjusting button (3) presses downwards.