KR101655307B1

KR101655307B1 - Orthodontic apparatus for malocclusion

Info

Publication number: KR101655307B1
Application number: KR1020150105018A
Authority: KR
Inventors: 김정경; 김성하
Original assignee: 김정경; 김성하
Priority date: 2015-07-24
Filing date: 2015-07-24
Publication date: 2016-09-07

Abstract

The present invention relates to a maxillary orthodontic apparatus for treating malocclusion with prognathic mandible (class III malocclusion), in which the maxilla is posteriorly placed in relation to the normal mandible. The maxillary orthodontic apparatus of the present invention comprises: an upper base which is inserted into the maxillary teeth; a lower base which includes a support wire connected to be spaced apart therefrom in front side thereof, and is inserted into the mandibular teeth; and a traction means which connects the upper base to the support wire so that the maxilla can be towed in a front upper direction with respect to the prognathic mandible. The traction means includes: first and second latching parts included in the upper base; first and second traction parts included in the support wire; a first elastic member which connects the first latching part to the first traction part so that the upper base can be pressed forward; and a second elastic member which connects the second latching part to the second traction part so that a front end portion of the upper base can be lifted upward using the support wire as a support point. Accordingly, the maxillary orthodontic apparatus of the present invention allows the maxilla and mandible to be arranged in appropriate positions without requiring an additional orthodontic treatment on the maxilla to be arranged in a normal position.

Description

TECHNICAL FIELD [0001] The present invention relates to a maxillary occlusal device for treating a mandibular protruding type malocclusion,

The present invention relates to a maxillofacial apparatus for treating a mandibular protruding malocclusion (Class III malocclusion) in which the upper jaw is located rearward with respect to a normal mandible, comprising an upper base fitted to the upper teeth group; A lower base fitted to the group of mandibular teeth; And a pulling means for connecting the upper base and the support wire so that the upper and lower teeth are pulled upward and upward with respect to the protruding mandible, wherein the pulling means comprises a first hooking portion provided on the upper base, A first pulling part provided on the supporting wire, a second pulling part, a first elastic member connecting the first pulling part and the first pulling part so as to press the upper base forward, And a second elastic member connecting the second latching portion and the second pulling portion and lifting the front end of the upper base upward by lifting the support wire as a fulcrum. And the mandible are mated at appropriate positions.

Malocclusion refers to an occlusal relationship in which the teeth are not aligned due to an inherent or acquired cause, or the state of up-and-down engagement deviates from a normal position, resulting in aesthetic and functional problems.

These malocclusions are classified as grade 1 to grade 3 according to the symptoms,

Class 1 malocclusion refers to cases where the teeth arrangement is irregular or the teeth arrangement is good but the upper and lower front teeth are tilted forward and the tooth protrudes or there is a gap between the teeth,

Class 2 malocclusion refers to a form in which the maxilla protrudes forward from the mandible,

Class III malocclusion refers to a form in which the mandible protrudes more than the maxilla in contrast to the above-mentioned class II malocclusion.

In general, Class I malocclusion is treated by orthodontic treatment using a dental orthodontist,

Class 2 and class 3 malocclusions can be treated by surgery (maxillary, mandibular, amniocentesis) or by using an occlusal device to inhibit or enhance the development of the jawbone and gradually move the tooth to the desired position.

Since surgery for Class II and III malocclusion is costly, difficult to maintain normal life for more than one year after surgery, and because of the high risk of surgery, the occlusal device is used to remove the problematic jawbone, And the dental treatment is performed in parallel.

Such an occlusion device is divided into a removable device which can be inserted into the oral cavity and a fixed device which is detached at the end of the treatment after the attachment.

On the other hand, Class III malocclusion is a case where the mandible is overgrown and the maxilla is less than normal. In cases where the maxilla is less grown than the normal one, that is, In the case of malocclusion,

The maxillary teeth and the mandibular teeth are connected with the bases of the occlusal devices, respectively, and the upper teeth are forced to be pulled forward for a long period of time.

However, since the mandibular protrusion type malocclusion with the maxilla behind the normal mandible is in a state in which the maxillary teeth are tilted toward the rear direction of the mandibular teeth, when the traction treatment using the conventional occlusal device is performed, And it is necessary to perform additional orthodontic treatment during treatment.

In other words, since the maxillary occlusion device for treating the mandibular protruding type malocclusions until now pulls the maxillary forward only, the maxillary incisors are not moved to the normal occlusal position due to the growth of the maxilla in the anterior part in the malocclusion of class III There is a problem that the treatment for calibrating again needs to be performed in parallel.

These additional calibrations increase the cost burden and cause longer treatment periods.

Accordingly, the present invention has been made to solve the above-mentioned problems,

The support wire provided on the lower base is supported by the support base so that the cost and the period can be shortened and the more accurate bite treatment can be achieved by inducing the growth of the maxilla to the occlusal position of the occlusion without needing to perform additional orthodontic treatment or continuous concurrent treatment. And a pulling means for pushing the upper end of the upper base forward while pushing the upper end of the upper base to the upper side so that the upper and lower teeth are pulled upwards.

It is another object of the present invention to provide a maxillary occlusion device which is easy to disassemble for traction and base disassembly when the base is worn and is easy to dismount from the base.

Another object of the present invention is to provide a maxillary occlusion device capable of performing faster and more accurate malocclusion treatment by increasing the supporting force for lifting the front end of the upper base upward by using the supporting wire as a fulcrum.

In order to achieve the above object, the present invention provides a maxillary occlusion device comprising:

The present invention relates to a maxillary occlusion device for treating a mandibular protruding malocclusion in which the maxilla is located at the rear side of a normal mandible,

An upper base fitted to the upper teeth group;

A lower base fitted to the group of mandibular teeth; And

And a pulling means for connecting the upper base and the supporting wire so that the upper and lower teeth are pulled toward the upper and lower sides with respect to the projected mandible,

The pulling means

A first engaging part provided on the upper base, a second engaging part provided on the upper base,

A first traction portion provided on the supporting wire, a second traction portion,

A first elastic member connecting the first latching portion and the first pulling portion to pull the upper base forward;

And a second elastic member connecting the second latching part and the second pulling part to lift the front end of the upper base upward by using the support wire as a fulcrum.

In the maxillary occlusion device according to the present invention,

Wherein the first latching portion comprises a first latching ring provided on the upper base,

The second latching portion includes a first support portion extending forward from the upper base and a second latching ring provided at an end of the support portion,

The first pulling portion is constituted by a first pulling ring extending forward from the supporting wire,

The second pulling portion is constituted by a second pulling ring extending downward from the supporting wire,

Wherein the first elastic member is composed of both the first engagement ring and the first elastic body coupled to the first traction ring and exerting an elastic force in a direction in which the first elastic member is contracted,

And the second elastic member is composed of a second elastic body that has both ends thereof coupled to the second hooking ring and the second hooking ring and exerting an elastic force in a direction in which the second elastic member contracts to form the supporting point. do.

In the maxillary occlusion device according to the present invention,

And the second latching portion includes a reinforcing portion formed by extending upward or downward or upward and downward between the first support portion and the second latching ring.

Further, in the maxillofacial device according to the present invention,

Wherein the second latching portion comprises a tubular body embedded in the upper base,

The second pulling portion is constituted by a third pulling ring connected to the support wire downwardly and formed in a horizontal direction,

The second elastic member includes a second support portion inserted into the tubular body and extended forward of the upper base, a ring portion extending from the front end of the second support portion to extend downwardly and hooked to the third pulling ring, And an elastic portion for connecting the second support portion and the annular portion to exert an elastic force in a widening direction to form the support point.

In the mandibular prolate-type orthokeratology treatment in which the maxilla is located behind the normal mandible, the pulling means for inducing the protrusion of the maxilla is pulled forward with the front end of the maxilla lifted upwards It is possible to perform more accurate and quick occlusion treatment without needing to perform separate orthodontic treatment or concurrent treatment by pulling the maxillary to the anterior part of the upper side, and it is possible to shorten the cost and treatment period due to the treatment, The connection and disconnection of the means is easy, so that the user can use the device more easily.

1 and 2 are sample photographs of an upper base and a lower base of the maxillofacial apparatus according to the present invention.
FIGS. 3 and 4 are photographs showing a state in which a maxillofacial device is worn by a tooth model according to an embodiment of the present invention. FIG.

While the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In the drawings, the same reference numerals are used for the same reference numerals, and in particular, the numerals of the tens and the digits of the digits, the digits of the tens, the digits of the digits and the alphabets are the same, Members referred to by reference numerals can be identified as members corresponding to these standards.

In the drawings, the components are expressed by exaggeratingly larger (or thicker) or smaller (or thinner) in size or thickness in consideration of the convenience of understanding, etc. However, It should not be.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the term " comprising " or " consisting of ", or the like, refers to the presence of a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

It is to be understood that the first to second aspects described in the present specification are merely referred to in order to distinguish between different components and are not limited to the order in which they are manufactured, It may not match.

1 and 2, the locking portions 31 and 32 and the pulling portions 33 and 34 may be formed in the same manner as in the first embodiment. The direction in which gravity acts is referred to as a downward direction, and the upper, lower, left, and right directions are determined as they are in the direction of gravity acting on the basis of the direction viewed from the front. Unless otherwise specified, directions are specified in accordance with this standard.

Hereinafter, the maxillofacial apparatus according to the present invention will be described with reference to the accompanying drawings.

FIGS. 3 and 4 are photographs of the upper base 10 of the present invention and photographs of the lower base 20 taken in FIGS. 1, 2, As shown in Figure 4,

The maxillofacial apparatus according to the present invention mainly includes an upper base 10 worn on the maxilla, a lower base 20 worn on the mandible, and a pulling means 30 for pulling the upper and lower teeth upward toward the upper side .

The upper base 10 and the lower base 20 can be worn on the upper teeth group T1 and the lower teeth group T2 respectively and can be worn on the upper teeth group T1 of the therapist before the occlusion therapy, The maxillary occlusion device is removed during daily life and the maxillary occlusion device is worn only during sleep or at other times so that the maxillary occlusion therapy is performed .

The upper and lower bases 20 are made of synthetic resin such as resin which is harmless to the human body.

The tooth group receiving grooves of the upper and lower bases 10 and 20 are recessed by the number of teeth of the corresponding tooth group, and in this case, the extracted teeth may be recessed.

In order that the upper and lower bases 10 and 20 can be firmly fixed to the corresponding tooth groups, the fixing wires 11 and 21, which are fitted on both sides of the rear ends of the respective bases, do.

The upper base 10 is provided with a body portion 12 having a shape of an upper ceiling of the lower base 20, while the central portion of the lower base 20 is hollow, .

Meanwhile, the lower base 20 further includes a support wire 22 connected to the lower base 20 at a predetermined distance from the front.

The support wire 22 is a metal wire formed in an arc shape in accordance with the teeth of the mandibular teeth T2 so that the lower lip is accommodated in the empty space between the front end of the lower base 20 and the support wire 22 .

A mounting member 23 having an insertion hole 23a is embedded on both sides of the rear end of the lower base 20 so as to control the distance between the front end of the lower base 20 and the support wire 22 And both ends of the support wire 22 are inserted into the insertion hole 23a.

As a result, the position of the first pulling part 33 and the second pulling part 34 provided on the support wire 22 can be adjusted.

Reference numeral 24 denotes a regulating portion formed by bending the wire so that the entire length of the supporting wire 22 can be adjusted by adjusting the width of the regulating portion 24 by using a medical plier or the like.

Although there is no limitation on the bending direction of the adjusting portion 24, it is preferable that the adjusting portion 24 is bent downward so as to be in close contact with the gums of the mandibular teeth T2 for convenience of use.

The pulling means 30 of the present invention connects the upper base 10 and the support wire 22 so that the upper portion of the upper base 10 is pulled upward and upward,

A first engaging part 31 provided on the upper base 10, a second engaging part 32,

A first pulling portion 33 provided on the support wire 22, a second pulling portion 34,

A first elastic member 35 connecting the first hooking portion 31 and the first pulling portion 33 to pull the upper base 10 forward;

The second holding portion 32 and the second holding portion 34 are connected to each other so that the front end portion of the upper base 10 is lifted upward by using the supporting wire 22 as a fulcrum 30S, And includes an elastic member 36.

The first retaining portion 31 and the first retracting portion 33 are disposed on both sides of the base so as to allow the front end of the maxilla to be lifted upward while the upper and lower teeth are balanced on the oral structure, It is preferable that the second engaging portion 32 and the second pulling portion 34 are disposed at the center between the first engaging portions 31 and the second pulling portions 34.

Thus, conventional occlusion devices for treating mandibular protrusive malocclusion with the maxilla behind the normal mandibles require that the upper base be pulled only forward and the maxillary to be corrected in the mandibular protruding malocclusion structure to grow anteriorly downward On the contrary,

The present invention is characterized in that the first elastic member 35 pulls the upper base 10 forward while the front end of the upper base 10 is lifted up through the second elastic member 36 (T1) comes into contact with the entire upper surface of the mandibular teeth (T2) when the occlusion therapy is completed, so that it can be quickly and accurately performed without performing additional orthodontic treatment or concurrent treatment Mandibular protruding malocclusion can be treated.

Hereinafter, the constitution of the pulling means 30 will be described in more detail with reference to the embodiments of the present invention, and duplicated description of the same constitution will be omitted by omitting the same reference numerals.

First, as a first embodiment of the present invention,

The first latching part 31 is composed of a first latching ring 311 provided in the upper base 10,

The second latching part 32 includes a first support part 321 extending forward from the upper base 10 and a second latching ring 322 provided at an end of the first support part 321 And,

The first pulling portion 33 is composed of a first pulling ring 331 extending forward from the supporting wire 22,

The second pulling portion 34 is composed of a second pulling ring 341 extending downward from the supporting wire 22,

The first elastic member 35 is constituted by the first elastic member 351 having both ends thereof connected to the first elastic member 311 and the first elastic member 331 and exerting an elastic force in a direction in which the elastic member is contracted And,

The second elastic member 36 is coupled to the second hooking ring 322 and the second hooking ring 341 at both ends thereof and exerts an elastic force in a direction in which the second elastic member 36 contracts, And a second elastic body 361 for forming the supporting point 30S.

As described above, a pair of first hooking loops 311 are fixed in the form of one end embedded in both front ends of the upper base 10 for a balanced pulling of the maxilla, and a pair of first pulling hooks 331 are connected to the support wire 22 in such a manner as to extend in both forward and oblique directions,

The second pulling collar 341 is provided at the inner center of the first pulling collar 331 at the lower end of the front end of the supporting wire 22 and the second pulling collar 322 is provided at a position corresponding to the second pulling collar 341 As shown in Fig.

In this case, as shown in the drawing, it is more preferable that the second hooking ring 322 and the second pulling ring 341 are also formed as a pair of symmetrical left and right.

The first hooking ring 311 is engaged with the first hooking hook 311 and the first hooking hook 331 so that the first hooking hook 311 can be engaged with the first hooking hook 311 and the first hooking hook 331, And the first pulling collar 331 is bent upward from the front end of the first pulling collar 331 to open forward.

The second pulling collar 341 may be bent upward from the lower end so that the second elastic body 361 can be engaged with the second hooking collar 322 and the second pulling collar 341 In order to improve the lifting support force of the upper base 10 using the lever principle, the second hooking ring 322 is positioned relatively forward of the second hooking ring 341, 2 drawing ring 341 (the drawing is a sample photographic road including all the configurations of the second embodiment described later, and only the second pulling ring 341 without the third pulling ring 342 is used as the supporting wire 22 alone) And the engagement end 341a is provided at the end of the second elastic body 361 to prevent the second elastic body 361 from coming off.

Unlike the second pulling collar 341, since the second hooking collar 322 is pressed downward by the second elastic body 361, the second hooking collar 322 is bent in a U-shape at the end of the first supporting portion 321, .

The first and second elastic members 351 and 361 may be formed of various materials having elasticity in the direction in which both ends are contracted. In the drawings, a ring-shaped rubber band having high elasticity is typically used. And it is confirmed that it is engaged with each pulling portion.

However, the first and second elastic members 351 and 361 may be of different shapes or types, such as a straight rubber band.

The second latching part 32 includes a reinforcing part 323 formed by extending upward or downward or upward and downward between the first support part 321 and the second latching ring 322.

The reinforcing portion 323 reinforces the rigidity of the second hooking ring 322 which is pushed downward from the front of the fulcrum 30S to be described later so that the rear end of the first supporting portion 321 when the lifting effect using the lever principle is generated So that only the portion of the second latching ring 322 is prevented from bending downward without being subjected to the upward pressing.

When the first elastic body 351 is coupled and coupled between the first hooking ring 311 and the first hooking ring 331, the elastic force of the first elastic body 351 is applied to the lower base 20 fixed by the elastic force of the first elastic body 351 The upper base 10 is pressed forward and pulled.

The second pulling collar 341 fixed by the elastic force of the second elastic body 361 is engaged with the second pulling collar 321 and the second pulling collar 341, A portion where the first support portion 321 contacts and contacts the support wire 22 acts as a fulcrum 30S so that the upper base 10 are lifted up as the front end portion thereof is lifted upward.

That is, the second elastic body 361 is pulled downward by the second hooking ring 322 so that the front end portion of the first supporting portion 321 is also downwardly pressed. The supporting point 30S is formed and the rear end of the first supporting portion 321 is pressed upward by the lever principle so that the front end portion of the upper base 10 is pressurized upward.

This is due to the structure in which the upper and lower jaw joints are connected to each other along the axis of the posterior jaw, although not shown in the figure, and the pressure generated by the lifting effect is applied only to the front end of the upper base 10, To induce the maxilla to grow to a normal occlusal position.

Next, as a second embodiment of the present invention,

The second latching part 32 is composed of a tube body 324 embedded in the upper base 10,

The second pulling portion 34 is composed of a third pulling ring 342 connected to the support wire 22 in a downward direction and formed in a horizontal direction,

The second elastic member 36 includes a second support portion 362 inserted into the tubular body 324 and extended forward of the upper base 10 and a second support portion 362 extending downward from the front end of the second support portion 362, And an elastic force is exerted in the extending direction by connecting the second support portion 362 and the ring portion 363 to the supporting point 30S And an elastic part 364 for forming the elastic part.

The second embodiment differs from the first embodiment in the construction and the manner of pulling the upper base 10 forward, except that the upper end of the upper base 10 is lifted upward.

A pair of tubular bodies 324 are embedded and fixed at both front ends of the upper base 10 and the second elastic member 36 is inserted into the pair of tubular bodies 324 as in the first embodiment A pair of second supporting portions 362 and a pair of elastic portions 364 and the loop portion 363 extends downward from the both side elastic portions 364 and is bent forward at the end portions.

The reason why the second support portion 362 of the second elastic member 36 is embedded in the upper base 10 and is not fixed is that the upper portion of the second elastic portion 36 is pulled upward toward the upper side, And adjust the lifting strength of the second elastic member 36 through adjustment of the position of the hook 363.

This is because the elasticity is exerted in the direction in which the second elastic body 361 of the first embodiment is contracted so that the length is displaced so that the length and the elastic force can be freely adjusted in accordance with the movement distance of the maxillary movement while the second elastic member 36 ) Is a metallic material such as a wire, and the position of the supporting point 30S is changed by the movement distance of the maxillary, resulting in a change in the lifting strength.

Here, the elastic portion 364 of the second elastic member 36 has a shape in which elasticity is exerted at both side ends bent in a similar " a " shape, i.e., in a direction in which the ring portion 363 and the second support portion 362 are extended So that the elastic force can be variously realized by the material of the second elastic member 36, the bending structure of the elastic portion 364,

As shown in the figure, the torsion spring 361 is formed of a torsion spring formed of a circular twisted portion 364a so as to exert an elastic force in a rotation direction of the circular twist portion 364a, that is, in a direction in which the ring portion 363 and the second support portion 362 are extended It is more advantageous to ensure a strong and uniform lifting effect beyond a certain level.

When the second elastic member 36 is coupled to connect between the tubular body 324 and the hook portion 363, the third hook 342 fixed due to the connection structure of the upper and lower jaws, 364 are pressed down and pulled down so that the portion where the elastic portion 364 or the second support portion 362 comes in contact with and contacts the support wire 22 acts as the fulcrum 30S, The rear end portion of the second support portion 362 is pressed upward so that the front end portion of the upper base 10 is pressurized upward.

In the meantime, according to the present invention, the second hooking portion 32, the second hooking portion 34 and the second elastic body 361 of the first embodiment, the second hooking portion 32 of the second embodiment, (34) and a second elastic member (36).

That is, both the first embodiment and the second embodiment can be applied in combination to increase the strength of the lifting effect generated at the front end of the upper base 10.

In this case, as shown in the figure, a second pulling collar 341 in the form of a straight line extending downward from the hook 363 of the second embodiment is provided.

If the first embodiment and the second embodiment are applied at the same time, accurate and fast occlusion treatment of the maxilla through the lifting effect becomes possible even in the case of patients with severe degree of correction of the third degree of correction.

While the present invention has been described with reference to the accompanying drawings, it is to be understood that the present invention is not limited to the above embodiments, but various modifications, alterations, and substitutions may be made by those skilled in the art And should be construed as falling within the scope of protection of the present invention.

T: Tooth model T1: Upper tooth group
T2: mandibular teeth group
10: upper base 11: fixed wire
12:
20: lower base 21: fixed wire
22: support wire 23: mounting member
24:
30: pulling means 31: first engaging portion
311: first hooking ring 32: second hooking part
321: first support portion 322: second retaining ring
323: reinforcement portion 324: tubular body
33: first pull portion 331: first pull ring
34: second pull section 341: second pull ring
342: third pulling collar 35: first elastic member
351: first elastic member 36: second elastic member
361: second elastic body 362: second supporting portion
363: Ring portion 364: Elastic portion

Claims

The present invention relates to a maxillary occlusion device for treating a mandibular protruding malocclusion in which the maxilla is located at the rear side of a normal mandible,
An upper base fitted to the upper teeth group;
A lower base fitted to the group of mandibular teeth; And
And a pulling means for connecting the upper base and the supporting wire so that the upper and lower teeth are pulled toward the upper and lower sides with respect to the projected mandible,
The pulling means
A first engaging part provided on the upper base, a second engaging part provided on the upper base,
A first traction portion provided on the supporting wire, a second traction portion,
A first elastic member connecting the first latching portion and the first pulling portion to pull the upper base forward;
And a second elastic member connecting the second latching portion and the second pulling portion to allow the front end of the upper base to be lifted upward by using the support wire as a fulcrum.

The method according to claim 1,
Wherein the first latching portion comprises a first latching ring provided on the upper base,
The second latching portion includes a first support portion extending forward from the upper base and a second latching ring provided at an end of the support portion,
The first pulling portion is constituted by a first pulling ring extending forward from the supporting wire,
The second pulling portion is constituted by a second pulling ring extending downward from the supporting wire,
Wherein the first elastic member is composed of both the first engagement ring and the first elastic body coupled to the first traction ring and exerting an elastic force in a direction in which the first elastic member is contracted,
And the second elastic member is composed of a second elastic body that has both ends thereof coupled to the second hooking ring and the second hooking ring and exerting an elastic force in a direction in which the second elastic member contracts to form the supporting point. The maxillary occlusion device.

3. The method of claim 2,
And the second locking portion includes a reinforcing portion formed by bending and extending upward or downward or between upper and lower sides between the first supporting portion and the second locking ring.

The method according to claim 1,
Wherein the first latching portion comprises a first latching ring provided on the upper base,
Wherein the second latching portion comprises a tubular body embedded in the upper base,
The first pulling portion is constituted by a first pulling ring extending forward from the supporting wire,
The second pulling portion is constituted by a third pulling ring connected to the support wire downwardly and formed in a horizontal direction,
Wherein the first elastic member is composed of both the first engagement ring and the first elastic body coupled to the first traction ring and exerting an elastic force in a direction in which the first elastic member is contracted,
The second elastic member includes a second support portion inserted into the tubular body and extended forward of the upper base, a ring portion extending from the front end of the second support portion to extend downwardly and hooked to the third pulling ring, And an elastic portion that forms the supporting point by exerting an elastic force in a direction of widening by connecting the second support portion and the annular portion.