WO2019177246A1

WO2019177246A1 - Punching assistant device

Info

Publication number: WO2019177246A1
Application number: PCT/KR2019/000027
Authority: WO
Inventors: 장동렬; 장정두; 조원호
Original assignee: 삼성전자주식회사
Priority date: 2018-03-13
Filing date: 2019-01-02
Publication date: 2019-09-19
Also published as: US20210039222A1; KR102571977B1; KR20190107904A

Abstract

A punching assistant device is disclosed. The punching assistant device comprises: a first shaft disposed perpendicular to a work surface; a second shaft coupled perpendicularly to the first shaft; and a grinder mounting member coupled to the second shaft, wherein the grinder mounting member is rotatable about the first shaft.

Description

Perforation aid

The present disclosure relates to a perforation assistance device that is lightweight and portable, and enables simple and precise perforation.

Recently, due to space utilization and aesthetic reasons, a perforated ceiling of a room consisting of a tex or an integrated panel is perforated, and a product is installed in the perforated hole.

To this end, conventionally, when perforating the ceiling of the room, the perforation was performed by drawing a circular sketch on the ceiling by the worker and cutting a part of the ceiling directly along the circular sketch drawn on the ceiling by the worker. .

However, this conventional perforation method, it is difficult for the worker to perforate accurately along the circular sketch by hand, there was a problem that the precision of the perforated circle is changed according to the skill of the operator. In particular, when the worker performs the perforation by cutting the ceiling along the circular sketch using a grinder which is a commonly used perforator, there is a problem that precise perforation is difficult due to the straightness of the grinder.

An object of the present disclosure is to provide a perforation assistance device that can use a grinder, a perforated machine that is commonly used and spread, to perform a fast and accurate circular perforation on the ceiling to meet the requirements of the customer.

In addition, another object of the present disclosure is to provide a perforation auxiliary device that is portable and easy to minimize the volume.

The present disclosure for achieving the above object includes a first axis disposed perpendicular to the working surface, a second axis vertically coupled to the first axis and a grinder mounting member coupled to the second axis, wherein the grinder The mounting member may be rotatable about the first axis.

The grinder mounting member may include a first opening opened toward the working surface and a second opening communicating with the first opening and into which the grinder can be inserted.

The grinder mounting member is coupled to the second shaft, and includes a receiving portion having a receiving space including the first opening and the second opening, and detachably coupled to the receiving portion to partially remove the second opening. It may include a cover to cover.

The receiving portion may include a work support surface in contact with the work surface.

The accommodation portion may include a dust discharge port communicating with the accommodation space.

The accommodation portion may include a coupling hole into which the second shaft is inserted and coupled.

It may include a connecting member rotatably connected to one end of the first shaft, the one end of the second shaft is connected.

The connecting member may include a first portion rotatably connected to one end of the first shaft, a hinge shaft coupled to the first portion, and a second pivotably coupled to the hinge shaft, and connected to one end of the second shaft. It can include a part.

At least one of the first axis and the second axis may have a multi-stage structure, the length of which may vary.

It may further include a first fixing member coupled to one end of the first shaft in contact with the working surface.

The first fixing member may include a fixing pin penetrating the working surface.

The first fixing member may include a first supporting surface having the fixing pin disposed therein and having a diameter larger than the diameter of the one end of the first shaft.

And a second fixing member coupled to the other end opposite to the one end of the first shaft and having a second support surface having a larger diameter than the diameter of the other end of the first shaft.

The accommodation portion may include at least one support portion protruding toward the accommodation space.

In addition, the present disclosure for achieving the above object, the first axis disposed perpendicular to the working surface, the second axis coupled to the first axis perpendicularly, the grinder mounting member coupled to the second axis and the first A connecting member rotatably connected to one end of the shaft and connected to one end of the second shaft, wherein the grinder mounting member is detachable from the grinder and is in contact with the opening and the working surface opened toward the working surface; A perforation assistance device comprising a work support surface can be provided.

1 is a perspective view showing a perforation assistance device according to an embodiment of the present disclosure.

Figure 2 is an exploded perspective view showing a perforation auxiliary device according to an embodiment of the present disclosure.

FIG. 3 is an enlarged view of part III of the perforation assistance device shown in FIG. 2.

4 is a perspective view showing the grinder mounting member.

5 is an exploded perspective view of the grinder mounting member.

FIG. 6 is a side view illustrating the receiving part of the grinder mounting member viewed from the direction VI shown in FIG. 5.

7 is a perspective view showing a state in which a grinder is coupled to a perforation auxiliary device.

8 is a perspective view showing that the length of the first axis is changed.

9 and 10 are perspective views showing the folding process of the perforation auxiliary device.

11 and 12 are perspective views showing a modified embodiment of the perforation auxiliary device.

DETAILED DESCRIPTION In order to fully understand the configuration and effects of the present disclosure, preferred embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, but may be implemented in various forms and various changes may be made. However, the description of the embodiments is provided only to make the disclosure of the present disclosure complete, and to fully inform the scope of the invention to those skilled in the art. In the accompanying drawings, for convenience of description, the sizes of the components are shown to be larger than they are, and the ratio of each component may be exaggerated or reduced.

Where a component is said to be "on" or "contacted" by another component, it may be directly in contact with or connected to another component, but it should be understood that there may be another component in between. something to do. On the other hand, when a component is described as being "on" or "directly" to another component, it may be understood that there is no other component in between. Other expressions describing the relationship between the components, such as "between" and "directly between", may also be interpreted as well.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms may be used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present disclosure, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

Singular expressions include plural expressions unless the context clearly indicates otherwise. The terms "comprise" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described on the specification, and that one or more other features or numbers, It may be interpreted that steps, actions, components, parts or combinations thereof may be added.

Unless otherwise defined, terms used in the embodiments of the present disclosure may be interpreted as meanings commonly known to those skilled in the art.

1 is a perspective view showing a perforation assistance device 1 according to an embodiment of the present disclosure, Figure 2 is an exploded perspective view showing a perforation assistance device 1 according to an embodiment of the present disclosure, Figure 3 is FIG. FIG. 3 is an enlarged view of part III of the perforation assistance device 1 shown in FIG.

Hereinafter, the structure of the perforation assistance device 1 according to an embodiment of the present disclosure will be described with reference to FIGS. 1 to 3.

The perforation assistance device 1 includes a first shaft 100, a second shaft 200, a connection member 300, a grinder mounting member 400, a first fixing member 500, and a second fixing member 600. Include.

The first shaft 100 may be disposed perpendicularly to the work surface S (see FIG. 7), which is a lower surface of the tex (T, see FIG. 7) constituting the ceiling, and may be disposed perpendicularly to the ground on the work space. Can be. In addition, the first shaft 100 may be disposed at the center of the opening to be punched. Accordingly, the perforation assistance device 1 rotates about the first shaft 100 to drill the work surface S into a circular opening. can do.

The first shaft 100 may be configured in a multi-stage structure whose length can be changed. Accordingly, the length of the first shaft 100 is adjusted according to the height from the floor to the ceiling of the various workspaces so that the first shaft 100 can be stably fixed between the floor and the ceiling.

The first shaft 100 may be a multi-stage structure composed of a plurality of shafts sequentially coupled along the longitudinal direction. For example, the first shaft 100 may include a plurality of pipes having different diameters, and the pipes having the smaller diameter may be sequentially inserted into the pipe having the largest diameter. Accordingly, the length of the first shaft 100 may be variable, and by reducing the volume, it may be easy to carry and convenient to store. The multi-stage structure of the first shaft 100 may be fixed to the changed length using a variety of fixing structures, such as a conventional bolt fixing structure, screw fixing structure.

In addition, the material of the first shaft 100 may be made of various materials as needed, such as plastic, steel.

The second shaft 200 may be vertically coupled to the first shaft 100, and the second shaft 200 may be vertically coupled to the first shaft 100 through the connection member 300.

Specifically, one end portion 200a of the second shaft 200 is connected to the connecting member 300, and the other end portion 200b positioned opposite to the one end portion 200a is connected to the grinder mounting member 400. .

The second axis 200 has a length constituting the radius of the opening to be perforated. Therefore, the length of the second shaft 200 is composed of a length corresponding to the radius of the opening to be punched in the working surface (S).

In addition, the second shaft 200 having various lengths may be applied to the perforation assistance device 1 according to the diameter of the opening to be perforated on the working surface S. FIG.

In addition, like the first shaft 100, the second shaft 200 may be configured to have a variable length, and the openings having various diameters may be opened by changing the length of the second shaft 200. Can be punched in.

The material of the second shaft 200 may be made of various materials as needed, such as plastic and steel.

Referring to FIG. 3, the connecting member 300 is rotatably connected to one end 100a of the first shaft 100, and one end 200a of the second shaft 200 is connected. Accordingly, the connecting member 300 may connect the first shaft 100 and the second shaft 200, and the second shaft 200 may be disposed perpendicularly to the first shaft 100. In addition, since the connecting member 300 is rotatably connected to the first shaft 100, the second shaft 200 may rotate about the first shaft 100.

In detail, the connection member 300 includes a first portion 301, a second portion 302, and a hinge shaft 303.

The first portion 301 is rotatably connected to one end 100a of the first shaft 100.

Specifically, the first portion 301 includes a first insertion hole 301a into which one end portion 100a of the first shaft 100 can be inserted.

The inner diameter D2 of the first insertion opening 301a is larger than the outer diameter D1 of the one end portion 100a of the first shaft 100. Accordingly, one end portion 100a of the first shaft 100 may be inserted into the first insertion hole 301a of the first portion 301, and the first portion 301 may be centered on the first shaft 100. Can rotate.

The second portion 302 is pivotally coupled to the hinge shaft 303 coupled to the first portion 301, and one end 200a of the second shaft 200 is fitted. Accordingly, the second portion 302 is pivoted about the hinge axis 303 (in the R direction of FIG. 9) so that the second axis 200 can be superimposed with the first axis 100.

The grinder mounting member 400 may be rotated about the first shaft 100 by being connected to the second shaft 200. Accordingly, the grinder mounting member 400 rotates about the first shaft 100 in a state in which a conventional cutting device such as grinder G (see FIG. 7) is mounted on the grinder mounting member 400. Through the grinder G which rotates about 100, a circular opening can be easily perforated in the working surface S. FIG. Since the grinder G is the same as or similar to the conventional technology, a description thereof will be omitted, and a detailed structure of the grinder mounting member 400 will be described later.

In addition, the first fixing member 500 is coupled to one end portion 100a of the first shaft 100, and the second fixing member 600 is provided at the other end portion 100b positioned opposite to the one end portion 100a. Combined.

The first fixing member 500 is coupled to one end portion 100a of the first shaft 100 to contact the working surface S.

In detail, the first fixing member 500 includes an insertion part 501, a first support surface 502, and a fixing pin 503.

The insertion part 501 is formed with an outer diameter D4 smaller than the inner diameter D2 of the first insertion hole 301a and is inserted into the first insertion hole 301a. Inside the insertion portion 501, a second insertion hole 501a having an inner diameter D3 larger than the outer diameter D1 of the one end portion 100a of the first shaft 100 is formed. Accordingly, one end portion 100a of the first shaft 100 is inserted into the second insertion hole 501a while the insertion portion 501 is inserted into the first insertion hole 301a.

In addition, when the insertion part 501 is fitted into the first insertion hole 301a, the first fixing member 500 and the connection member 300 may be integrally rotated about the first axis 100.

In addition, since the outer diameter D1 of the one end portion 100a of the first shaft 100 is smaller than the inner diameter D3 of the second insertion hole 501a, the outer diameter D1 of the one end portion 100a and the second insertion hole ( Through the clearance between the inner diameter (D3) of the 501a, the connecting member 300 and the first fixing member 500 can be integrally rotated around the fixed first shaft (100).

In addition, the outer diameter D1 of the one end portion 100a of the first shaft 100 is similar to the inner diameter D3 of the second insertion hole 501a so that the one end portion 100a of the first shaft 100 is the second insertion hole. In the case where an additional protrusion (not shown) is formed to fit in the 501a and interferes with the connecting member 300 along the lower outer circumferential surface of the insertion hole 501, the outer diameter D4 of the insertion hole 501 and the first protrusion are formed. 1 Through the play between the inner diameter (D2) of the insertion hole (301a), the connecting member 300 is centered on the first shaft 100 in a state where the first shaft 100 and the first fixing member 500 are integrally fixed. Can rotate.

However, if necessary, a bearing (not shown) is disposed between the one end portion 100a of the first shaft 100 and the second insertion hole 501a of the first fixing member 500, whereby the connecting member 300 is formed. It may be configured to rotate about one axis (100).

The first support surface 502 is formed integrally with the insertion portion 501, the diameter is larger than the diameter of the first shaft 100.

In detail, the first support surface 502 is a portion in contact with the work surface S, and the work surface (the first shaft 100 is formed through an area having a diameter larger than the outer diameter D1 of the first shaft 100). It can be fixed stably in S).

However, if necessary, the first support surface 502 may have various shapes having an area larger than a circular area formed of the outer diameter D1 of the first shaft 100.

The fixing pin 503 may be disposed above the first support surface 502 to penetrate the working surface S. FIG. Accordingly, the first shaft 100 can be stably fixed to the working surface S.

The fixing pin 503 is disposed at the center of the opening to be punched in the working surface S, and may penetrate the center of the opening to be punched.

The second fixing member 600 is coupled to the other end portion 100b opposite to the one end portion 100a of the first shaft 100.

In detail, the second fixing member 600 includes a second support surface 601, a second inserting portion 602, and a protrusion 603.

The second support surface 601 may stably support the first shaft 100 on the bottom of the work space through an area having a diameter larger than the diameter of the other end portion 100b of the first shaft 100. However, if necessary, the second support surface 601 may have various shapes having an area larger than the circular area formed of the diameter of the other end portion 100b of the first shaft 100.

The second inserting portion 602 is formed integrally with the second support surface 601 and is inserted into the other end portion 100b of the first shaft 100 so that the first shaft 100 and the second fixing member 600 are provided. Connect

The protruding portion 603 protrudes along the outer circumferential surface of the second inserting portion 602 and contacts the other end portion 100b of the first shaft 100 to support the first shaft 100.

4 is a perspective view showing the grinder mounting member 400, Figure 5 is an exploded perspective view of the grinder mounting member 400, Figure 6 is a side view showing the receiving portion of the grinder mounting member viewed from the direction VI shown in FIG.

Hereinafter, the concrete structure of the grinder mounting member 400 will be described with reference to FIGS. 4 to 6.

As described above, the grinder mounting member 400 may be coupled to the other end 200b of the second shaft 200 to rotate about the first shaft 100, and in the state where the grinder G is mounted. The opening can be perforated in the working surface S by rotating around the first axis 100.

The grinder mounting member 400 includes a receiving part 420 having a cover part 410 and a receiving space 403.

Specifically, the accommodation space 403 includes a first opening 401 open toward the working surface S and a second opening 402 in communication with the first opening 402 and into which the grinder G can be inserted. .

When the grinder G is coupled to the first opening 401, the blade of the grinder G may protrude toward the working surface S through the first opening 401. The shape of the first opening 401 may be formed in various shapes as necessary if the blade of the grinder G may protrude through the first opening 401.

The second opening 402 may have a shape corresponding to the outer shape of the grinder G.

The cover part 410 is detachably coupled to the receiving part 420 and covers a part of the second opening 402. Accordingly, when the grinder G is coupled to the grinder mounting member 400 to drill the work surface S, the cover part 410 may have fly ash generated during the drilling process through the second opening 402. It is possible to prevent scattering to the outside of the mounting member 400.

If necessary, the cover part 410 may have a variety of shapes as long as the grinder G is coupled to the grinder mounting member 400 so that no fly products are scattered to the outside of the grinder mounting member 400.

Receiving portion 420 forms the outer appearance of the grinder mounting member 400, the receiving space 403, the working paper surface 404, dust outlet 405, the seating surface 406, the support portion 407, the coupling opening 408 and bolt engagement opening 409.

The work support surface 404 abuts on the work surface S and is composed of a flat plate having a predetermined area. Accordingly, when the grinder G is mounted on the grinder mounting member 400 to drill the work surface S, the work surface S is disposed on the work support surface 404 so that the work surface S is stable. It can be punched in the supported state.

The dust discharge port 405 is formed at one side of the receiving portion 420 and communicates with the receiving space 403. The dust outlet 405 may discharge the by-product generated in the drilling process to the outside of the receiving portion 420. In addition, the dust discharge port 405 is connected to an external suction device (not shown) such as a cleaner can be more easily discharged by the fly.

The seating surface 406 may be in contact with the outer housing (not shown) of the grinder G, thereby stably fixing the grinder G to the grinder mounting member 400. The shape of the seating surface 406 may be in various shapes in contact with the outer housing of the grinder G to fix the outer housing of the grinder G.

The support part 407 protrudes from the seating surface 406 toward the accommodation space 403, and may be configured as at least one. At least one support 407 may interfere with the outer housing of the grinder G to stably fix the grinder G to the grinder mounting member 400. For example, the support part 407 is fitted to the outer housing of the grinder G seated on the seating surface 406, thereby stably fixing the grinder G to the accommodation space 403.

As shown in FIG. 6, the coupling opening 408 is formed outside the receiving portion 420, and the other end portion 200b of the second shaft 200 is inserted into the other end portion of the second shaft 200. 200b) is fitted. Accordingly, the coupling opening 408 may connect the grinder mounting member 400 and the second shaft 200.

The bolt coupling opening 409 is formed at one side of the accommodation portion 420 and communicates with the accommodation space 403. At least one bolted opening 409 may be formed. When a conventional bolt (not shown) is coupled to the bolt engaging opening 409, the bolt contacts the outer housing of the grinder G mounted on the grinder mounting member 400 so that the grinder G is attached to the grinder mounting member 400. It can be fixed stably within.

7 is a perspective view showing the grinder (G) is coupled to the perforation auxiliary device (1).

Hereinafter, referring to FIG. 7, the punching process through the punching assistance device 1 to which the grinder G is coupled will be described in detail.

First, the length of the first axis 100 is adjusted in accordance with the height between the floor T and the floor constituting the ceiling, so that the first axis 100 is disposed perpendicular to the text T. At this time, the fixing pin 503 of the first fixing member 500 connected to the one end portion 100a of the first shaft 100 passes through the tex T, whereby the first shaft 100 passes through the tex T. It can be fixed more stably.

Then, the grinder G is mounted on the grinder mounting member 400, and the work support surface 404 is in contact with the working surface S, and is coupled to the grinder mounting member 400 about the first axis 100. The grinder G rotates and cuts the working surface S. FIG.

Specifically, the grinder mounting member 400 and the grinder G rotate in the P direction along the circular trajectory C illustrated in FIG. 7, so that an opening having a radius corresponding to the length of the second shaft 200 is formed. Can be.

Accordingly, the tex (T) constituting the ceiling can be easily and accurately perforated in the shape of a circular trajectory (C), after which the desired product can be installed on the perforated portion. In addition, since the perforation assistance device 1 can be detachably mounted with a conventional grinder G, no additional cost for providing a separate perforator is consumed.

8 is a perspective view illustrating that the length of the first shaft 100 is deformed.

Hereinafter, a state in which the length of the first shaft 100 is changed will be described in detail with reference to FIG. 8.

As described above, the first shaft 100 has a multistage structure having different outer diameters, so that pipes having a smaller outer diameter may be inserted into the pipe having the largest outer diameter.

Accordingly, when the height from the floor to the ceiling is lower, the height of the first shaft 100 may be adjusted by inserting a part of the first shaft 100 in the Q direction, and the perforation assistance device 1 may be made at various heights. Can be used.

9 and 10 are perspective views illustrating a process of folding the perforation assistance device 1.

Hereinafter, referring to FIGS. 9 and 10, a folding process of the perforation assistance device 1 will be described in detail.

As described above, the length of the first axis 100 may vary. Specifically, the first shaft 100 is composed of pipes having different diameters, and pipes having a smaller diameter may be sequentially inserted into the pipe having the largest diameter.

The perforation assistance device 1 in the state of FIG. 1, as shown in FIG. 9, the pipes constituting the first shaft 100 may be inserted into a pipe having the largest outer diameter. Thereafter, the second shaft 200 connected to the connecting member 300 may pivot along the R direction about the hinge shaft 303 of the connecting member 300, and the perforation assistance device 1 may be folded as illustrated in FIG. 10. Can be a condition.

Accordingly, the perforation assistance device 1 is minimized in volume, which is easy for the worker to carry, and may also be easily stored.

11 and 12 are perspective views showing a modified embodiment of the present disclosure.

Hereinafter, with reference to FIG. 11 and FIG. 12, the modified Example of the perforation assistance apparatus 1 'is demonstrated concretely.

The perforation assistance device 1 ′ disclosed in FIGS. 11 and 12 includes a first shaft 100, a connection member 300, a grinder mounting member 400, and a first fixing member of the perforation assistance device 1 illustrated in FIG. 1. It includes the same configuration as the 500 and the second fixing member 600, and overlapping description is omitted.

The second shaft 200 ′ may have a multistage structure composed of a plurality of shafts sequentially coupled along the longitudinal direction. For example, the second shaft 200 ′ may include a plurality of pipes having different diameters, and the pipes having the smaller diameter may be sequentially inserted into the pipe having the largest diameter. Accordingly, the length of the second shaft 200 ′ may vary. The multi-stage structure of the second shaft 200 ′ may be fixed in length by using various fixing structures such as a bolt fixing structure and a screw fixing structure.

Accordingly, when the length of the second shaft 200 ′ is minimized, the volume of the perforation assistance device 1 ′ may be reduced to be portable and easy to store.

In addition, as described above, openings of various diameters can be drilled in the working surface S by changing the length of the second shaft 200 '. Accordingly, the perforation assistance device 1 ′ equipped with the grinder G may cut the opening in the work surface S in consideration of the sizes of various products to be installed.

In the above, various embodiments of the present disclosure have been described individually, but each embodiment is not necessarily implemented alone, and the configuration and operation of each embodiment may be implemented in combination with at least one other embodiment. .

In addition, while the preferred embodiments of the present disclosure have been shown and described above, the present disclosure is not limited to the above-described specific embodiments, and the technical field to which the present invention pertains without departing from the gist of the present disclosure claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present disclosure.

Claims

A first axis disposed perpendicular to the working surface;

A second shaft coupled perpendicularly to the first axis; And

And a grinder mounting member coupled to the second shaft.

The grinder mounting member is a perforation aids rotatable about the first axis.
The method of claim 1,

The grinder mounting member,

A first opening opened toward the working surface; And

And a second opening in communication with the first opening and into which the grinder can be inserted.
The method of claim 2,

The grinder mounting member,

A receiving part coupled to the second axis and having a receiving space including the first opening and the second opening; And

And a cover part detachably coupled to the receiving part to cover a part of the second opening.
The method of claim 3,

And the receiving portion includes a work support surface in contact with the work surface.
The method of claim 3,

The accommodation portion perforation auxiliary device comprising a dust discharge port in communication with the accommodation space.
The method of claim 3,

And the receiving portion includes a coupling hole into which the second shaft is inserted and coupled.
The method of claim 1,

And a connecting member rotatably connected to one end of the first shaft and connected to one end of the second shaft.
The method of claim 7, wherein

The connecting member,

A first portion rotatably connected to one end of the first shaft;

A hinge shaft coupled to the first portion;

And a second portion pivotally coupled to the hinge shaft and to which one end of the second shaft is connected.
The method of claim 1,

At least one of the first axis and the second axis is a perforation assistance device having a multi-stage structure that can vary in length.
The method of claim 1,

And a first fixing member coupled to one end of the first shaft to be in contact with the working surface.
The method of claim 10,

The first fixing member is a perforation auxiliary device comprising a fixing pin penetrating the working surface.
The method of claim 11,

The first fixing member is a perforation assistance device comprising a first support surface is disposed the fixing pin is larger than the diameter of the one end of the first shaft.
The method of claim 1,

And a second fixing member coupled to the other end opposite to the one end of the first shaft and having a second support surface having a diameter larger than the diameter of the other end of the first shaft.
The method of claim 3,

The perforation assisting device includes at least one support projecting toward the receiving space.
A first axis disposed perpendicular to the working surface;

A second shaft coupled perpendicularly to the first axis;

A grinder mounting member coupled to the second shaft; And

And a connecting member rotatably connected to one end of the first shaft and connected to one end of the second shaft.

And the grinder mounting member includes a grinder detachable, an opening opened toward the work surface, and a work support surface in contact with the work surface.