CN220158414U - Tooth gap saw - Google Patents

Abstract

The utility model discloses a tooth gap saw, belongs to the field of oral appliances, and can solve the problem that a handle of the existing tooth gap saw is easy to fall off due to the fact that the handle and a saw blade assembly are not tightly fixed. The interdental saw comprises a saw blade assembly and a handle; the saw blade assembly includes a mounting shaft; the side wall of the connecting section of the mounting shaft connected with the handle comprises at least one plane, and the connecting section is provided with a clamping hole which is recessed along the radial direction of the mounting shaft; the handle comprises a handle and a clamping assembly; the front end of the handle is provided with a mounting blind hole which is recessed inwards from the end face axially, the outer side wall of the handle is provided with a mounting hole along the radial direction, the mounting hole is communicated with the mounting blind hole, and when the connecting section stretches into the mounting blind hole to be in place, the mounting hole corresponds to the clamping hole; the clamping assembly is arranged in the mounting hole and can move along the axial direction of the mounting hole so that the front end of the clamping assembly stretches into or withdraws from the clamping hole. The handle of the dental crevice saw is not easy to fall off.

Description

Tooth gap saw

Technical Field

The utility model relates to the technical field of oral appliances, in particular to a dental crevice saw.

Background

Teeth are the hardest organs of the human body, and play roles in keeping the appearance of the face, assisting in pronunciation and the like besides playing roles in cutting, biting and the like. At present, people pay more and more attention to tooth health. In the treatment of dental problems, there are cases where a tooth space needs to be sawed to achieve the purposes of cleaning, treatment, etc. of the tooth space. A commonly used tool for sawing tooth slits is a tooth slit saw. The existing handle of the interdental saw can be detached to facilitate replacement of the saw blade assembly at the front part of the interdental saw, but the existing handle of the interdental saw is not tightly fixed with the saw blade assembly, so that the handle is easy to fall off.

Disclosure of Invention

The embodiment of the utility model provides a tooth gap saw, which can solve the problem that a handle of the existing tooth gap saw is easy to fall off due to the fact that the handle and a saw blade assembly are not tightly fixed.

The embodiment of the utility model provides a dental clearance saw, which comprises a saw blade assembly and a handle; the saw blade assembly includes a mounting shaft; the side wall of the connecting section of the mounting shaft connected with the handle comprises at least one plane, and the connecting section is provided with a clamping hole which is recessed along the radial direction of the mounting shaft; the handle comprises a handle and a clamping assembly; the front end of the handle is provided with a mounting blind hole which is recessed inwards from the end face axially, the outer side wall of the handle is provided with a mounting hole along the radial direction, the mounting hole is communicated with the mounting blind hole, and when the connecting section stretches into the mounting blind hole to be in place, the mounting hole corresponds to the clamping hole; the clamping assembly is arranged in the mounting hole and can move along the axial direction of the mounting hole so that the front end of the clamping assembly stretches into or withdraws from the clamping hole.

In one possible implementation, the clamping assembly includes a slider, a moving clamp, an elastic member, and a fixing bar; the mounting hole comprises a first chamber, a second chamber and a third chamber along the direction from the central axis of the handle to the outer side wall; the movable clamping piece comprises a cylinder and a ring piece, wherein the first end of the cylinder is arranged in the first cavity, the ring piece is arranged on the outer side wall of the second end of the cylinder, the ring piece and the second end of the cylinder are arranged in the second cavity, and the end face of the second end of the cylinder and the section perpendicular to the axis of the cylinder form an acute angle; the elastic piece is sleeved on the column body, and two ends of the elastic piece respectively prop against the lower surface of the ring piece and the bottom surface of the second chamber; the sliding block is arranged in the first cavity and can slide along the axial direction of the handle, and the lower end of the sliding block is provided with an inclined surface matched with the end surface of the second end of the cylinder; and the two sides of the sliding block perpendicular to the sliding direction of the sliding block at the corresponding position of the third chamber are respectively provided with a fixing strip.

In one possible implementation, the mounting shaft includes a first sub-shaft and a second sub-shaft; one end of the first sub-shaft is rotationally connected with one end of the second sub-shaft; the other end of the second sub-shaft is provided with the connecting section.

In one possible implementation, the side wall of the connecting section of the mounting shaft connected to the handle comprises a plane, and the plane and the clamping hole are arranged at opposite positions of the outer side wall of the connecting section.

In one possible implementation, the saw blade assembly further includes an inverted U-shaped mounting bracket and a saw blade; the first vertical leg of the inverted U-shaped mounting frame is fixed with one end of the mounting shaft, which is far away from the handle; the saw blade can be detachably connected to the U-shaped opening of the inverted U-shaped mounting frame.

In one possible implementation, the saw blade assembly further includes a catch; a clamping groove is formed in a second vertical leg of the inverted U-shaped mounting frame, and a notch is formed in the side face of one end of the saw blade; the clip comprises a first clamping plate, a second clamping plate and a third clamping plate, the first clamping plate and the third clamping plate are arranged in parallel, and the second clamping plate is arranged between the first clamping plate and the second clamping plate, so that the interval distance between the first clamping plate and the third clamping plate is consistent with the sum of the thicknesses of the second vertical legs and the saw blades; the clip is arranged in the clamping groove and can slide along the clamping groove; the first vertical leg of the inverted U-shaped mounting rack is detachably connected with the other end of the saw blade.

In one possible implementation manner, the second vertical leg is further provided with a fixed column; when the notch is aligned with the clamping groove, a fixing hole is formed in the saw blade at a position corresponding to the fixing column.

In one possible implementation, the first upright leg is provided with at least one set of fasteners; the fixing piece comprises a cylinder and a straight-edge oval piece, one end of the cylinder is fixed with the first vertical leg, and the other end of the cylinder is connected with the surface of the straight-edge oval piece; the other end of the saw blade is provided with a straight-edge elliptical groove corresponding to the position and the size of the straight-edge elliptical piece, and the cylinder body can slide along the straight-edge elliptical groove.

One or more technical solutions provided in the embodiments of the present utility model at least have the following technical effects or advantages:

embodiments of the present utility model provide a interdental saw comprising a saw blade assembly and a handle. The saw blade assembly includes a mounting shaft. The side wall of the connecting section of the mounting shaft connected with the handle comprises at least one plane, and the connecting section is provided with a clamping hole which is recessed along the radial direction of the mounting shaft. The handle includes a handle grip and a clamping assembly. The front end of the handle is provided with a mounting blind hole which is recessed inwards from the end face axially, the outer side wall of the handle is provided with a mounting hole along the radial direction, the mounting hole is communicated with the mounting blind hole, and when the connecting section stretches into the mounting blind hole to be in place, the mounting hole corresponds to the clamping hole. The clamping assembly is arranged in the mounting hole and can move along the axial direction of the mounting hole so that the front end of the clamping assembly stretches into or withdraws from the clamping hole. According to the tooth gap saw provided by the embodiment of the utility model, at least one plane is arranged on the side wall of the connecting section of the mounting shaft connected with the handle, and when the mounting shaft is connected with the handle, the handle can be prevented from falling off due to random rotation of the handle. When the connecting section of the installation shaft stretches into the installation blind hole on the handle to be in place, the front end of the clamping component arranged in the installation hole stretches into the clamping hole arranged on the connecting section of the installation shaft, the installation shaft can be clamped, and the handle is not easy to fall off in the use process of the dental saw kerf. When the front end of the clamping assembly exits from the clamping hole, the mounting shaft is not limited by the clamping assembly any more, and then the mounting shaft can be separated from the handle, so that the saw blade assembly and the handle can be conveniently detached.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the description of the embodiments of the present utility model will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present utility model, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a construction of a dental crevice saw according to an embodiment of the present utility model;

FIG. 2 is a view in the direction A of FIG. 1;

FIG. 3 is a schematic view of a saw blade assembly according to an embodiment of the present utility model;

FIG. 4 is a view in the direction B-B of FIG. 3;

FIG. 5 is a schematic view of the structure of a saw blade according to an embodiment of the present utility model;

fig. 6 is a schematic structural view of a clip according to an embodiment of the present utility model.

Icon: 1-a saw blade assembly; 11-mounting a shaft; 111-a first sub-axis; 112-a second sub-axis; 12-clamping holes; 13-an inverted U-shaped mounting rack; 131-first vertical leg; 132-a second vertical leg; 1321-a card slot; 133-fixing the column; 134-cylinder; 135-straight-sided oval sheets; 14-saw blade; 141-notch; 142-fixing holes; 143-straight-sided elliptical grooves; 15-clip; 151-a first card; 152-a second card; 153-a third card; 2-handle; 21-a handle; 211-a first chamber; 212-a second chamber; 213-a third chamber; 22-clamping assembly; 221-a slider; 222-moving the clip; 223-an elastic member; 224-fixing strips.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the embodiments of the present utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the embodiments of the present utility model and simplify description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. The terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Furthermore, the terms "mounted," "connected," "coupled," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the embodiments of the present utility model will be understood by those of ordinary skill in the art according to specific circumstances.

Referring to fig. 1, an embodiment of the present utility model provides a dental crevice saw, which includes a saw blade assembly 1 and a handle 2. As shown in fig. 3, the saw blade assembly 1 includes a mounting shaft 11. The side wall of the connecting section of the mounting shaft 11 connected to the handle 2 comprises at least one plane, as shown in fig. 4, which shows a schematic structural view of the side wall of the connecting section of the mounting shaft 11 connected to the handle 2 comprising one plane. The connecting section is provided with a clamping hole 12 recessed radially along the mounting shaft 11. As shown in fig. 1, the handle 2 includes a grip 21 and a snap assembly 22. The front end of the handle 21 is provided with a mounting blind hole which is recessed inwards from the end face axially, the outer side wall of the handle 21 is provided with a mounting hole along the radial direction, the mounting hole is communicated with the mounting blind hole, and when the connecting section stretches into the mounting blind hole to be in place, the mounting hole corresponds to the clamping hole 12 in position. The clamping assembly 22 is disposed within the mounting bore and is movable in an axial direction of the mounting bore such that its front end extends into or out of the clamping bore 12.

According to the dental crevice saw provided by the embodiment of the utility model, at least one plane is arranged on the side wall of the connecting section of the mounting shaft 11 connected with the handle 2, and when the mounting shaft 11 is connected with the handle 2, the handle 2 can be prevented from falling off due to random rotation of the handle 2. When the connecting section of the installation shaft 11 stretches into the installation blind hole on the handle 21 to be in place, the front end of the clamping component 22 arranged in the installation hole stretches into the clamping hole 12 arranged on the connecting section of the installation shaft 11, the installation shaft 11 can be clamped, and the handle 2 is not easy to fall off in the use process of the dental kerf. When the front end of the clamping assembly 22 exits from the clamping hole 12, the mounting shaft 11 is not limited by the clamping assembly 22, and then the mounting shaft 11 can be separated from the handle 2, so that the saw blade assembly 1 and the handle 2 can be conveniently detached.

With continued reference to FIG. 1, the clamping assembly 22 includes a slider 221, a moving clamp 222, an elastic member 223, and a fixing bar 224. As shown in fig. 1, the mounting hole includes a first chamber 211, a second chamber 212, and a third chamber 213 in a direction from the central axis of the handle 2 to the outer side wall. The moving clamping piece 222 comprises a cylinder and a ring piece, wherein the first end of the cylinder is arranged in the first chamber 211, the ring piece is arranged on the outer side wall of the second end of the cylinder, the ring piece and the second end of the cylinder are arranged in the second chamber 212, and the end face of the second end of the cylinder and the section perpendicular to the axis of the cylinder form an acute angle, namely the second end of the cylinder is an inclined plane. The elastic member 223 is sleeved on the column body, and two ends of the elastic member respectively prop against the lower surface of the ring piece and the bottom surface of the second chamber 212. The slider 221 is provided in the first chamber 211 and is slidable in the axial direction of the handle 21, and is provided at the lower end with a slope matching with the end face of the second end of the cylinder. As shown in fig. 2, at the position corresponding to the third chamber 213, two sides of the slider 221 perpendicular to the sliding direction thereof are respectively provided with a fixing strip 224, and the fixing strips 224 can fasten the slider 221 to prevent the slider 221 from being ejected. Further, the elastic member 223 may be a spring, a compression spring, or the like.

Referring to fig. 1, when the connecting section of the mounting shaft 11 extends into the mounting blind hole to be in place, the mounting hole on the handle 21 corresponds to the position of the clamping hole 12 on the connecting section, the sliding block 221 slides from right to left, the inclined plane at the lower end of the sliding block 221 slides along the end face of the second end of the cylinder, the cylinder receives downward force, the first end of the cylinder extends into the clamping hole 12, and at this time, the elastic piece 223 is in a compressed state, and as two sides of the sliding block 221 perpendicular to the sliding direction of the sliding block are respectively provided with a fixing strip 224, the sliding block 221 is fastened, the first end of the cylinder firmly extends into the clamping hole 12, and the mounting shaft 11 and the handle 21 are firmly locked, and the handle 21 does not fall off. When the handle 21 needs to be detached from the mounting shaft 11, the sliding block 221 slides from left to right, the inclined plane at the lower end of the sliding block 221 slides along the end face of the second end of the cylinder, at this time, under the action of the elastic force of the elastic piece 223, the cylinder moves upwards, the first end of the cylinder exits the clamping hole 12, the locking constraint on the mounting shaft 11 is released, and the mounting shaft 11 can be removed from the mounting blind hole of the handle 21. The clamping component 22 provided by the embodiment of the utility model has smart structure and is easy to realize.

As shown in fig. 1 and 3, the mounting shaft 11 includes a first sub-shaft 111 and a second sub-shaft 112. One end of the first sub-shaft 111 is rotatably connected to one end of the second sub-shaft 112. The other end of the second sub-shaft 112 is provided with a connection section.

In practice, such as with posterior socket angles, the orientation of each tooth is different, and the intra-oral space is limited, resulting in inconvenience in the operation of the existing interdental saw. One end of the first sub-shaft 111 of the mounting shaft 11 is rotatably connected with one end of the second sub-shaft 112, so that the slit saw of the embodiment can swing at a certain angle during use, and the slit saw can move at a small angle during use, thereby facilitating use of the slit saw. Further, one end of the first sub-shaft 111 may be provided with a spherical structure, one end of the second sub-shaft 112 is provided with a spherical groove, and the spherical structure is slightly tightly matched with the spherical groove, so that the first sub-shaft 111 can rotate relative to the second sub-shaft 112 only with slight force, and the purpose of small-angle movement of the dental crevice saw can be achieved.

As shown in fig. 4, the side wall of the connecting section of the mounting shaft 11 to which the handle 2 is connected includes a flat surface, which is provided at a position opposite to the outer side wall of the connecting section with the card hole 12. When the connecting section of the mounting shaft 11 is arranged in the mounting blind hole of the handle 21, one plane can prevent the mounting shaft 11 from rotating relative to the handle 21, and meanwhile, only one plane is arranged, so that the mounting shaft 11 is better processed. The plane and the clamping hole 12 are arranged at the opposite position of the outer side wall of the connecting section, so that the clamping force received by the connecting section of the mounting shaft 11 is more uniform and the clamping effect is better after the front end of the clamping assembly 22 stretches into the clamping hole 12.

Referring to fig. 1 and 3, the blade assembly 1 further includes an inverted U-shaped mounting bracket 13 and a blade 14. The first leg 131 of the inverted U-shaped mounting bracket 13 is fixed to the end of the mounting shaft 11 facing away from the handle 2. The saw blade 14 can be detachably connected to the U-shaped opening of the inverted U-shaped mounting frame 13, so that the saw blade 14 can be conveniently detached, other parts can be recycled through disinfection, and resources are saved.

The saw blade assembly 1 further comprises a catch 15. As shown in fig. 3, the second vertical leg 132 of the inverted U-shaped mounting bracket 13 is provided with a clamping groove 1321, and as shown in fig. 5, the side surface of one end of the saw blade 14 is provided with a notch 141. As shown in fig. 6, the clip 15 includes a first card 151, a second card 152, and a third card 153, the first card 151 and the third card 153 being disposed in parallel, the second card 152 being disposed between the first card 151 and the second card 152 such that the distance between the first card 151 and the third card 153 coincides with the sum of the thicknesses of the second vertical leg 132 and the saw blade 14. As shown in fig. 1, the clip 15 is provided in the card slot 1321 and is slidable along the card slot 1321. The first vertical leg 131 of the inverted U-shaped mounting bracket 13 is detachably connected with the other end of the saw blade 14.

According to the clip 15 provided by the embodiment of the utility model, the clip 15 is arranged on the clamping groove 1321 on the second vertical leg 132 of the inverted U-shaped mounting frame 13, when the saw blade 14 needs to be clamped, the clip 15 is firstly slid upwards along the clamping groove 1321, the notch 141 arranged on the side surface of one end of the saw blade 14 is aligned with the clamping groove 1321, and as the spacing distance between the first clamping plate 151 and the third clamping plate 153 of the clip 15 is consistent with the sum of the thicknesses of the second vertical leg 132 and the saw blade 14, the clip 15 is slid downwards along the clamping groove 1321, and as shown in fig. 1, the clip 15 can clamp the saw blade 14 on the inverted U-shaped mounting frame 13. When the saw blade 14 needs to be taken out, the clamp 15 slides upwards along the clamping groove 1321, and the locking constraint of the clamp 15 on the saw blade 14 is released, so that the saw blade 14 can be detached from the second vertical leg 132 of the inverted U-shaped mounting frame 13.

Referring to fig. 3, a fixing post 133 is further provided on the second leg 132. When the notch 141 is aligned with the slot 1321, as shown in fig. 5, a fixing hole 142 is provided in the saw blade 14 corresponding to the fixing post 133. When the saw blade 14 needs to be fixed on the second vertical leg 132, the fixing post 133 on the second vertical leg 132 is clamped into the fixing hole 142 on the saw blade 14, so that the saw blade 14 can be further reinforced, the saw blade 14 can be positioned, and the notch 141 and the clamping groove 1321 can be aligned conveniently.

As shown in fig. 1 and 3, at least one set of fasteners is provided on the first leg 131. Fig. 3 shows a schematic structure of the first leg 131 with two sets of fixing members. The fixing member includes a cylinder 134 and a straight-sided elliptic piece 135, one end of the cylinder 134 is fixed to the first vertical leg 131, and the other end is connected to the surface of the straight-sided elliptic piece 135. As shown in fig. 5, the other end of the saw blade 14 is provided with a straight-sided elliptical groove 143 corresponding to the position and size of the straight-sided elliptical piece 135, and the cylinder 134 can slide along the straight-sided elliptical groove 143. When the saw blade 14 needs to be installed, the straight-edge elliptical sheets 135 of the fixing piece on the first vertical leg 131 are correspondingly clamped into the straight-edge elliptical grooves 143 arranged on the saw blade 14, then the saw blade 14 is pulled leftwards to enable the saw blade 14 to slide and clamp relative to the first vertical leg 131, and then the other end of the saw blade 14 is fixed with the second vertical leg 132. When the saw blade 14 needs to be detached, the other end of the saw blade 14 is released from the second vertical leg 132, then the saw blade 14 is pushed to the right, the saw blade 14 slides relative to the first vertical leg 131, and when the straight-edge elliptical piece 135 is aligned with the straight-edge elliptical groove 143, the saw blade 14 can be detached from the first vertical leg 131. The detachable mode of the saw blade 14 provided by the embodiment of the utility model has a simple structure, and is easy to realize and can be manufactured.

In this specification, each embodiment is described in a progressive manner, and the same or similar parts of each embodiment are referred to each other, and each embodiment is mainly described as a difference from other embodiments.

The above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the present utility model; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced with equivalents; such modifications and substitutions do not depart from the spirit of the utility model.

Claims (8)

1. A tooth gap saw, which is characterized by comprising a saw blade component and a handle;

the saw blade assembly includes a mounting shaft;

the side wall of the connecting section of the mounting shaft connected with the handle comprises at least one plane, and the connecting section is provided with a clamping hole which is recessed along the radial direction of the mounting shaft;

the handle comprises a handle and a clamping assembly;

the front end of the handle is provided with a mounting blind hole which is recessed inwards from the end face axially, the outer side wall of the handle is provided with a mounting hole along the radial direction, the mounting hole is communicated with the mounting blind hole, and when the connecting section stretches into the mounting blind hole to be in place, the mounting hole corresponds to the clamping hole;

the clamping assembly is arranged in the mounting hole and can move along the axial direction of the mounting hole so that the front end of the clamping assembly stretches into or withdraws from the clamping hole.

2. The dental crevice saw of claim 1, wherein the clamping assembly comprises a slider, a moving clamp, an elastic member, and a fixing bar;

the mounting hole comprises a first chamber, a second chamber and a third chamber along the direction from the central axis of the handle to the outer side wall;

the movable clamping piece comprises a cylinder and a ring piece, wherein the first end of the cylinder is arranged in the first cavity, the ring piece is arranged on the outer side wall of the second end of the cylinder, the ring piece and the second end of the cylinder are arranged in the second cavity, and the end face of the second end of the cylinder and the section perpendicular to the axis of the cylinder form an acute angle;

the elastic piece is sleeved on the column body, and two ends of the elastic piece respectively prop against the lower surface of the ring piece and the bottom surface of the second chamber;

the sliding block is arranged in the first cavity and can slide along the axial direction of the handle, and the lower end of the sliding block is provided with an inclined surface matched with the end surface of the second end of the cylinder;

and the two sides of the sliding block perpendicular to the sliding direction of the sliding block at the corresponding position of the third chamber are respectively provided with a fixing strip.

3. The dental crevice saw of claim 1, wherein said mounting shaft comprises a first sub-shaft and a second sub-shaft;

one end of the first sub-shaft is rotationally connected with one end of the second sub-shaft;

the other end of the second sub-shaft is provided with the connecting section.

4. The dental crevice saw of claim 1, wherein the side wall of the connecting section of the mounting shaft to which the handle is connected includes a flat surface disposed opposite the outer side wall of the connecting section from the socket.

5. The interdental saw according to claim 1 wherein the saw blade assembly further comprises an inverted U-shaped mounting bracket and a saw blade;

the first vertical leg of the inverted U-shaped mounting frame is fixed with one end of the mounting shaft, which is far away from the handle;

the saw blade can be detachably connected to the U-shaped opening of the inverted U-shaped mounting frame.

6. The interdental saw according to claim 5 wherein the saw blade assembly further comprises a catch;

a clamping groove is formed in a second vertical leg of the inverted U-shaped mounting frame, and a notch is formed in the side face of one end of the saw blade;

the clip comprises a first clamping plate, a second clamping plate and a third clamping plate, the first clamping plate and the third clamping plate are arranged in parallel, and the second clamping plate is arranged between the first clamping plate and the second clamping plate, so that the interval distance between the first clamping plate and the third clamping plate is consistent with the sum of the thicknesses of the second vertical legs and the saw blades;

the clip is arranged in the clamping groove and can slide along the clamping groove;

the first vertical leg of the inverted U-shaped mounting rack is detachably connected with the other end of the saw blade.

7. The dental crevice saw of claim 6, wherein the second leg is further provided with a fixing post;

when the notch is aligned with the clamping groove, a fixing hole is formed in the saw blade at a position corresponding to the fixing column.

8. The dental crevice saw of claim 6, wherein said first upstanding leg has at least one set of fasteners disposed thereon;

the fixing piece comprises a cylinder and a straight-edge oval piece, one end of the cylinder is fixed with the first vertical leg, and the other end of the cylinder is connected with the surface of the straight-edge oval piece;

the other end of the saw blade is provided with a straight-edge elliptical groove corresponding to the position and the size of the straight-edge elliptical piece, and the cylinder body can slide along the straight-edge elliptical groove.