KR200319233Y1 - hinge assembly - Google Patents

Abstract

The present invention relates to a hinge assembly of a more improved form, the housing 10 is fixed to the body; A rotary cam 20 integrally connected to the cover or door D and rotatable within the housing 10 according to the rotation of the door or cover; A sliding cam (30) installed to reciprocate in interaction with the rotary cam (20); A main torque spring (2) compressed or extended by the reciprocating motion of the sliding cam (30) to impart a predetermined rotational torque to the cover or door; A damping spring 4 for attenuating the door or cover at a predetermined position against the main torque spring 2; A rotating rod 40 which is rotatable with the rotary cam 20 in a rotation section of at least a portion of the rotary section of the rotary cam 20 in interaction with the rotary cam 20; It characterized in that it comprises a frictional resistance generating portion (5) for generating a frictional resistance by interacting with at least one surface of the rotating rod 40 rotated in the housing (10).

Description

Hinge assembly

The present invention relates to a hinge assembly configured to achieve a reduction in the rotational speed in a predetermined section of the door or cover that is rotated at a predetermined position by the rotational torque, and more particularly, within the rotation section of the door or cover. A hinge assembly that allows a door or cover to be rotatable in more various aspects.

Conventionally, a hinge structure for changing the rotational torque of a door or a cover by interaction between two cams and thus compression and extension of the main torque spring has been developed, for example, a mobile phone, a refrigerator (especially a kimchi refrigerator) or various It is widely used for doors.

However, such a hinge structure has a large impact on the hinge structure itself and the main body of the apparatus due to the large impact of the door or cover in the closed position or the open position of the door or cover.

In this regard, the present applicant has proposed a hinge structure for reducing the impact of the end of the door or cover by providing a damping spring in itself against the main torque spring as described above.

The conventional hinge structure is applied to a mobile phone or a kimchi refrigerator, etc., and has a very advantageous effect in reducing the impact of the end of the door, while the opening and closing aspect of the rotating section is standardized, and thus it is not suitable for use in the hinge structure of various doors. .

In particular, the conventional hinge structure has a problem that it is impossible to keep the door or cover at a fixed point almost at a stationary state.

In this regard, the inventors have developed a new and improved hinge assembly that allows for smoother attenuation and also allows for more varied opening and closing patterns of the door or cover.

The present invention is provided with a rotating cam and a sliding cam, by the interaction of the cams and the action of the springs, in the conventional hinge assembly that is given a rotational torque to the door and the end impact of the door is reduced, It is an object of the present invention to provide a hinge assembly configured to further generate a frictional resistance that enables various opening and closing aspects of a door according to the rotation of the rotary cam.

1 is a perspective view showing a hinge assembly according to an embodiment of the present invention.

Figure 2 is an exploded perspective view of the hinge assembly of Figure 1;

3A is a sectional view taken along the line I-I of FIG. 1, showing a hinge assembly in the closed position of the door.

3B is a cross-sectional view of the FIG. 1 hinge assembly taken along II-II of FIG. 3A.

4A and 4B are cross-sectional views of the FIG. 1 hinge assembly showing when the door is in a resistance start position, and FIG. 4B is a cross-sectional view taken along II-II of FIG. 4A.

5A and 5B are cross-sectional views of the FIG. 1 hinge assembly when the door is in the switching position, and FIG. 5B is a cross-sectional view taken along II-II of FIG. 5A.

6A and 6B are cross-sectional views of the FIG. 1 hinge assembly when the door is in a coexisting position where damping springs and attenuation by frictional resistance coexist, FIG. 6B is a cross-sectional view taken along II-II of FIG. 6A.

7A and 7B are cross-sectional views of the hinge assembly of FIG. 1 when the door is in the open position, and FIG. 6B is a cross-sectional view taken along II-II of FIG. 6A.

8 is a view schematically showing a state in which the door is moved from the closed position to the open position.

9 is an exploded perspective view showing a hinge assembly according to another embodiment of the present invention.

10 is a longitudinal cross-sectional view of the hinge assembly of FIG. 9.

11 is a view showing applications of the hinge assembly according to the present invention.

In order to achieve the above object, the present invention, the housing is fixed to the main body; A rotary cam integrally connected to the door or cover and rotatable within the housing according to the rotation of the door or cover; A sliding cam installed to reciprocate in interaction with the rotary cam; A main torque spring compressed or extended by a reciprocating motion of the sliding cam to impart a predetermined rotational torque to the door; A damping spring for attenuating the door or cover at a predetermined position against the main torque spring; A rotating rod rotatably interacting with the rotary cam in interaction with the rotary cam and in at least a portion of the rotary section of the rotary cam; And a frictional resistance generating unit that interacts with at least one surface of the rotating rod rotated in the housing to generate frictional resistance.

Here, the frictional resistance generating unit preferably fixed to the housing includes a hollow inner housing for generating a frictional resistance in contact with the outer ring of the rotating rod in contact with the outer ring.

The frictional resistance generating unit further includes a tapered pin that is rotatably fixed in the inner housing, and the rotating rod has a tapered hollow corresponding to an outer circumferential surface of the tapered pin so as to allow insertion of the tapered pin. It is provided in, it is preferable that the frictional resistance between the hollow inner surface of the rotary rod and the outer peripheral surface of the tapered pin.

In addition, it is preferable that an oil for fluid friction resistance is interposed between the hollow inner surface of the rotating rod and the outer circumferential surface of the tapered pin and between the outer circumferential surface of the rotating rod and the inner surface of the inner housing in contact with the outer circumferential surface. .

In addition, the tapered pin has a male thread portion on a portion of its outer circumferential surface, the rotating rod has a female thread portion corresponding to the male thread portion on the hollow inner surface with a length longer than the male thread portion, the inner housing of the tapered pin The pin head is provided with its own portion, and the pin head is moved forward and backward by the interaction of the male screw portion and the female screw portion, so that the hollow inner surface of the rotary rod and the outer peripheral surface of the tapered pin, and the rotation Preferably, the frictional resistance between the outer circumferential surface of the round bar and the inner surface of the inner housing in contact with the outer circumferential surface is adjusted.

The rotating cam has a hollow structure and has a protruding step piece formed on an inner side of the hollow, and the rotating rod includes a locking groove formed on its outer circumferential surface to interact with the step piece, and the rotary cam During the rotation, it is preferable that in at least a portion of the rotation angle section of the rotary cam, the engaging piece is engaged with the engaging groove and the rotation of the rotary cam and the rotating rod in a predetermined angle section. ,

On the other hand, when the door or the cover is opened and closed, it is assembled so that the engaging groove interaction between the step of the rotating cam and the rotating rod during the predetermined angle section, there is, during the predetermined angle section when opening or closing the door or cover, The rotating cam is preferably idling.

In addition, the housing and the inner housing are each provided with a stepping hole and a locking jaw respectively corresponding to each other, the locking jaw is caught by the stepping hole, the inner housing is assembled to be fixed to the housing, the housing Is preferably provided with a break groove formed at one end so as to allow the opening of the housing to be opened, to enable insertion of the inner housing when the inner housing with the locking jaw is inserted into the housing.

The rotating rod has a tapered portion converging toward one end on an outer circumferential surface, the inner housing has a tapered hollow corresponding to the tapered portion, and the tapered portion of the inner housing and the hollow surfaces of the inner housing are mutually It is desirable to bring about frictional resistance in contact.

Alternatively, the inner housing includes a main body and a tapered hollow rod that forms a tapered hollow that fits tightly to the hollow of the main body, wherein the tapered hollow of the tapered hollow rod is mutually connected to the tapered portion of the rotating rod. It acts to generate frictional resistance, and the tapered hollow part is preferably made of fluorine or urethane rubber material.

Referring now to the accompanying drawings, preferred embodiments of the present invention will be described in detail.

1 is a perspective view illustrating a hinge assembly 1 according to the present embodiment, FIG. 2 is an exploded perspective view of the hinge assembly 1 of FIG. 1, and FIG. 3A is a cross-sectional view taken along II of FIG. 1, FIG. 3B is a cross-sectional view taken along the P-P of FIG. 3A.

1 to 3B, the main assembly of the hinge assembly 1 is compressed or extended by the interaction between the housing 10, the rotary cam 20, the sliding cam 30, and the cams. It can be seen that it comprises a spring (2) and damping spring (4).

Rotating cam 20 is a continuous cam curve that extends through the shaft hole 12 of one end of the housing and is connected to the cover or door integrally 22 and the two top portions and the valley portion The camp profile 24 which has a form is provided integrally.

The sliding cam 30 is provided with another camping profile 34 corresponding to the camp profile 24 of the rotating cam 20 at one end thereof, and can reciprocate back and forth by the rotation of the rotating cam 20. It is supposed to be.

In addition, the sliding cam 30 has a hollow structure as a whole, so that the hollow rod 26 integrally extending from the rotary cam 20 can be located inside the hollow 36 of the sliding cam 30 itself. Let's do it.

On the other hand, the main torque spring 2 is extended or compressed by the interaction between the rotary cam 20 and the sliding cam 30 is installed to provide a variety of rotation torque values according to the opening and closing section of the hinge structure.

In this embodiment, the main torque spring 2 is interposed between the sliding cam 30 and the inner housing 50 fixed to the other end of the housing 10. Here, the inner housing 50 is a part involved in the frictional resistance generating means to be described below.

In addition, the damping spring (4) is a factor that affects the rotational torque of the hinge assembly (1) together with the main torque spring (2), in particular, when the door or cover is opened and closed, the expansion torque of the main torque spring (2) By providing a damping force against the rotation of the door or cover by reducing the impact by the door or cover to prevent the failure of the hinge assembly (1) and the body (not shown) or to prevent the knocking or closing sound of the door or cover It serves to reduce.

In this embodiment, the damping spring 4 is interposed between the end of the hollow rod 26 of the rotary cam 20 and the inner step wall 36a of the hollow 36 of the sliding cam 30.

Now, the friction resistance generating means briefly mentioned above will be described in more detail. The friction resistance generating means generates a resistance force at least at a predetermined position when opening or closing the door or cover, so that the door or cover together with the damping spring 4. It is possible to open and close the operation of the smoother, in particular, the damping spring (4) can be operated at a time difference with the more diversified and can be opened and closed operation of the soft door or cover.

In the present embodiment, the frictional resistance generating means includes a rotary rod 40, a tapered pin 60 and the inner housing 50 to interact with the rotary rod 40.

As briefly mentioned above, the internal housing 50 is a part that is integrally assembled to the other end of the housing 10 described above, and the support 52 having a wide cross section for supporting the main torque spring 2 described above. It is an overall cylindrical hollow body having a locking jaw 54 corresponding to the step 14 of the housing 10 on the outer peripheral surface of the support portion 52 is provided.

At this time, the housing 10 is the housing 10 so that the inner housing 50 is inserted so that the locking jaw 54 can be easily caught in the stepping hole 12 to fix the two parts (10, 50) to each other. A plurality of fracture grooves 13 extending in the longitudinal direction from the other end of the. That is, by the breaking groove 13, the housing 10 can be elastically deformed to a predetermined size at its end, and by the elastic deformation, the inner housing 50 can be preferably mounted in the housing 10. have.

In addition, one end of the rotary rod 40 is located in the inner hollow 26a of the hollow rod 26 of the rotary cam 20 and the other end is located in the hollow of the inner housing 50. At this time, from Figure 3a, it can be seen that the hollow of the inner housing 50 forms a taper shape corresponding to the taper portion 42 of the rotary rod 40.

The hollow rod 26 of the rotary cam 20 is integrally provided with a step piece 262 that protrudes inward, and the rotary rod 40 is concavely partitioned on the outer circumferential surface thereof so that the step piece 262 is formed. It has a gumming groove 44 that can interact with.

The interaction between the step piece 262 and the engaging groove 44 is that, when the door or cover is rotated and the rotary cam 20 is rotated accordingly, the rotary round bar 40 rotates together with the rotary cam 20. Makes it possible.

In this embodiment, the angle range in which the engaging groove 44 is formed is larger than the angle range in which the step piece 262 is formed, which means that the rotary cam 20 and the rotary rod 40 are rotated together only in a predetermined angle section. Means that.

In addition, the rotating rod 40 is extended long beyond the hollow 36 of the sliding cam 34, its tapered portion 42 is loosely inserted and maintained in the tapered inner hollow 56 of the inner housing 50 And, when the rotating rod 40 is rotated, a frictional resistance resistance is generated between the outer surface of the rotating rod 40 and the inner surface of the inner housing 50.

In this embodiment, an oil such as grease oil is interposed between the outer surface of the rotary round bar 40 and the inner surface of the inner housing 50 to generate smooth frictional resistance, that is, fluid resistance.

On the other hand, the rotary rod 40 is provided with a tapered hollow 46 on the inside, the tapered hollow 46 is the tapered pin 60 mentioned above is located tapered of the tapered pin 60 It is possible to generate another resistance between the outer circumferential surface and the tapered hollow surface of the rotating rod 40, more preferably fluid resistance by oil.

At this time, the tapered pin 60 can be loosely fitted in the tapered hollow 46 in an optimal state by having a tapered shape as a component constituting a large feature of the present invention.

In particular, in the present embodiment, the tapered pin 60 has a male screw portion 63 formed from the vicinity of its own pin head 62 to a predetermined position on the outer circumferential surface of the tapered pin 60, A female threaded portion 43 formed on the male threaded portion 63 is formed on a portion of the tapered hollow surface, and by turning the pin head 62, the tapered pin 60 with respect to the tapered hollow 46 of the rotary rod 40 is formed. You can finely adjust the fit. At this time, the tapered pin 60 is provided with a straight slot 62a for inserting the tapered pin 60 by turning the screwdriver in the pin head 62.

At this time, it will be apparent to those skilled in the art that the slotted groove 62a of the tapered pin 60 can be used to be fixed to the door or cover, and the tapered pin 60 is fixed in the housing 10. It should be apparent to those skilled in the art that it should be maintained.

In the foregoing description, the rotating rod 40, in particular, the outer circumferential surface and / or the hollow surface of the rotating rod 40 is in frictional contact with the inner housing 50 and / or taper pin 60, more specifically the fluid The frictional resistance is generated by the resistance contact, and in the present specification, the friction resistance generating unit 5 is collectively referred to as the frictional resistance generating part 5 which interacts with the rotating rod 40.

Referring now to FIGS. 3A to 8, the operation of this hinge assembly 1 by a door or cover (hereinafter collectively referred to as a door) will be described.

4A and 7B are views showing what opening and closing characteristics are opened from the closed position of the cover, that is, from the hinge assembly state 1 of FIGS. 3A and 3B.

In addition, FIG. 8 is a view schematically showing a product in which the hinge assembly 1 is assembled, and is a schematic view for explaining the operation of the hinge assembly together with FIGS. 3A to 7B.

In FIG. 8, the closing position P1 of the door D, the resistance generation start position P2 at which the frictional resistance is generated by the interaction of the rotary cam 20 and the rotary rod 30, and the main torque spring 2 are shown. The maximum compressed switching position P3, the coexistence position P4 in which attenuation by frictional resistance and attenuation by spring are present together, and an open position P5 in which the door D is completely opened are indicated.

When the door D of FIG. 8 is in the closed position P1, the hinge assembly 1 has its own main torque spring 2 on the first reference line TSR as shown in FIG. 3A. Located, the main torque spring 2 and the corresponding damping spring 4 are in an initial compressed state.

In addition, in the closed position (P1) of the door, as shown in Figure 3b, the rotary cam 20 is stationary and the step piece 262 of the rotary cam 20 is placed on the corresponding rotary ring 40 It does not work either.

Then, when the door of FIG. 8 is rotated by the angle section θ1 from the closed position P1 to the resistance generation start position P2, as shown in FIGS. 3A and 4A, the main torque spring 2 By the interaction of the rotary cam 20 and the sliding cam 30 is further compressed, the damping spring 4 is correspondingly extended.

3B and 4B, while the door is rotated from the closed position P1 to the resistance generation start position P2, the engaging piece 262 of the rotary cam 20 and the rotating rod 40 are caught. The grooves 44 do not interact with each other, and accordingly, no frictional resistance is generated in this angular section θ1 due to the interaction of any rotary cam 20 and the rotary ring 40.

Therefore, when the door is opened, no frictional resistance is generated in this angular section θ1, so that the door is easier to open than other sections below, making it possible to open the door with lighter force.

Then, when the door of FIG. 8 is rotated from the resistance generation start position P2 to the switching position P3, as shown in FIGS. 4A and 5A, the main torque spring 2 is rotated by the cam 20. And compression of the sliding cam 30 to the maximum, and the damping spring 4 is released correspondingly and positioned on the second reference line DSR.

4B and 5B, the step 262 of the rotating cam 20 caught by the locking groove 44 of the rotating rod 40 at the resistance generating position P2 rotates the rotating cam 20. In accordance with the rotating rod 40 is rotated, the rotating rod 40 is rotated in this way to interact with the inner housing 50 and the tapered pin 60 to generate a frictional resistance, preferably fluid resistance Can be.

Then, when the door D of Fig. 8 is rotated from the switching position P3 to the coexistence position P4, as shown in Figs. 5A and 6A, the main torque spring 2 is released and damped. The spring 4 is correspondingly compressed slightly against the stretching force of its main torque spring 2.

5B and 6B, the rotary rod 40 continues to rotate while interacting with the rotary cam 20, and thus, the damping spring and the damping spring caused by the frictional resistance are generated within this rotating section. There is a section θ3 where attenuation by 2) occurs at the same time.

Then, when the door D is rotated to the open position P5 past the coexistence position P4, as shown by FIG. 6A and FIG. 7A, the said main torque spring 1 has more compression release. In the closed position P5, the first reference line TSR of FIG. 3A is positioned again to be in an initial state, and correspondingly, the damping spring 4 is also returned to the initial state.

Also, in this section, as shown in Figs. 6B and 7B, the interaction between the rotating rod 40 and the rotating cam 20 still continues, so that the damping springs are attenuated with the above-mentioned damping spring while the door is completely opened. In addition to the function, in the open position P5 where the door D is completely opened, when the door is opened again, the engaging groove 44 of the rotating rod 40 and the rotation cam 20 are moved for a predetermined period. The pieces 262 do not interact with each other, so that the doors do not have to consume much force to open.

As a result, the hinge assembly 1 has an angular section θ1 where frictional resistance is not generated and frictional resistance is generated while the door D is rotated from the closed position P1 to the open position P4. The angular section θ2 includes an angular section θ2. In particular, the angular section θ2 in which the frictional resistance is generated includes an angular section θ3 in which attenuation by the frictional resistance and attenuation by the damping spring are simultaneously present.

Hereinafter, with reference to Figures 9 and 10, another embodiment of the present invention will be described. In the present embodiment, the same member number is used for the member having the same function as the previous embodiment, and the description already described in the foregoing embodiment will be omitted to avoid duplication.

As shown in Figs. 9 and 10, the hinge assembly 1 of the present embodiment has a tapered hollow in which its inner housing 50 is fitted to the body portion 50a and the hollow inner surface of the body portion 50a. A rod 50b.

In this tapered hollow bar 50, the inner hollow surface interacts with the outer circumferential surface of the rotary ring 40 similarly to the inner housing 50 in the previous embodiment. At this time, since the hollow bar 50b is made of fluorine or urethane-based reinforced rubber, it can be preferably used for a large door structure in which a large opening and closing torque is generated.

At this time, between the hollow surface of the hollow bar 50b and the outer circumferential surface of the rotary ring 40, oil for generating fluid resistance such as grease "

FIG. 11 illustrates other applications of the foregoing embodiments, and FIG. 11 (a) shows that the size of the step piece 262 of the rotary cam 20 is relatively smaller than that of the previous embodiment. An example of the hinge assembly 1 in which the time for interacting with the locking groove 44 of the rotating rod 40 having a shorter time is shortened, and thus the section in which the frictional resistance is generated is shortened.

In addition, (b) of Figure 11 is the size of the engaging piece 26 of the rotary cam 20 is larger than the previous embodiment and the locking groove 44 of the rotating round bar 40 having the same size as the previous embodiment and An example of the hinge assembly 1 is shown in which the interaction time is longer and thus the section in which the frictional resistance is generated is longer.

11 (c) shows that the engaging piece 262 of the rotary cam 20 fits almost snugly into the locking groove 44 of the rotary round bar 40, so that the frictional resistance is reduced over the entire period in which the door D is rotated. An example of the hinge assembly 1 to be produced is shown.

The present invention has the effect that it can be used in the hinge structure of the door or cover of various types by enabling a more various opening and closing pattern of the door or cover than in the conventional rotational section of the door.

In particular, the hinge assembly according to the present invention, as well as the conventional automatic rotation function, attenuation function, it is possible to stop the door at a predetermined position, enabling the user to use while fixing the door at a predetermined position.

In addition, the present invention further has the effect that the attenuation of the hinge assembly is smoother than in the prior art.

Claims (10)

A housing 10 fixed to the main body; A rotary cam 20 integrally connected to the cover or door D and rotatable within the housing 10 according to the rotation of the door or cover; A sliding cam (30) installed to reciprocate in interaction with the rotary cam (20); A main torque spring (2) compressed or extended by the reciprocating motion of the sliding cam (30) to impart a predetermined rotational torque to the cover or door; A damping spring 4 for attenuating the door or cover at a predetermined position against the main torque spring 2; A rotating rod 40 which is rotatable with the rotary cam 20 in a rotation section of at least a portion of the rotary section of the rotary cam 20 in interaction with the rotary cam 20; And a frictional resistance generating portion (5) which interacts with at least one surface of the rotating rod (40) rotated in the housing (10) to generate frictional resistance. The method of claim 1, The frictional resistance generating unit 5 is in contact with the outer circumferential surface of the rotating rod 40 while being fixed to the housing 10 to generate a frictional resistance in contact with the rotating rod 40 and the hollow inner housing 50 Hinge assembly comprising a) The method of claim 2, The frictional resistance generating unit 5 further includes a tapered pin 60 fixedly rotatably fixed in the inner housing 50, The rotary rod 40 is provided with a tapered hollow 46 corresponding to the outer circumferential surface of the tapered pin 60 to allow the insertion of the tapered pin 60 in itself, Hinge assembly, characterized in that the frictional resistance is generated between the hollow surface of the hollow 46 of the rotating rod and the outer peripheral surface of the tapered pin (60). The method of claim 3, wherein Fluid friction between the hollow hollow surface of the rotating rod 40 and the outer circumferential surface of the tapered pin 60 and between the outer circumferential surface of the rotating rod 40 and the inner surface of the inner housing 50 in contact with the outer circumferential surface thereof. A hinge assembly, characterized in that the resistance generating oil is interposed. The method of claim 3, wherein The tapered pin 60 has a male screw portion 63 on a portion of its outer circumferential surface, The rotating rod 40 has a female thread portion 43 corresponding to the male thread portion 63 on the hollow inner surface with a length longer than the male thread portion 63, The inner housing 50 is provided with a portion 52 that is caught on the pin head 62 of the tapered pin 60, As the pin head 62 is advanced and retracted by the interaction of the male screw portion 63 and the female screw portion 46, the hollow surface of the hollow 46 of the rotary rod 40 and the tapered pin The hinge assembly, characterized in that the frictional resistance between the outer circumferential surface of the (60), and between the outer circumferential surface of the rotating rod 40 and the inner surface of the inner housing (50) in contact with the outer circumferential surface. The method according to any one of claims 1 to 5, The rotary cam 20 has a hollow structure and has a protruding step 262 formed on the hollow surface of the hollow 26a, The rotating rod 40 is provided with a locking groove 44 formed on its outer circumferential surface to interact with the walking piece 262, While the rotary cam 20 is rotated, at least a portion of the rotation angle section of the rotary cam 20, the step piece 262 is engaged with the engaging groove 44 to interact in a predetermined angle section The hinge assembly, characterized in that the rotation of the rotating cam 20 and the rotating rod 40 occurs together. The method of claim 6, When the door or the cover is opened and closed, it is assembled so that there is no interaction between the engaging piece 262 of the rotary cam 20 and the locking groove 44 of the rotary ring 40 during a predetermined rotation angle section, The hinge assembly, characterized in that the rotating cam 20 is idling during the predetermined angle section when opening or closing the door or cover. The method of claim 2, Each of the housing 10 and the inner housing 50 has a stepping hole 12 and a locking step 54 corresponding to each other, so that the locking step 54 is caught by the stepping hole 12. By this, the inner housing 50 is assembled to be fixed to the housing 10, The housing 10 has a rupture groove 13 formed to enable the housing 10 to open at the end, so that the inner housing 50 having the locking jaw 54 is inserted into the housing 10. Hinge assembly, characterized in that to enable the insertion of the inner housing (50). The method according to any one of claims 2 to 5, The rotary rod 40 has a tapered portion 42 that converges toward one end on the outer circumferential surface, The inner housing 50 has a tapered hollow 56 corresponding to the tapered portion 42, A hinge assembly, characterized in that the tapered portion (42) of the inner housing (50) and the surface of the hollow (56) of the inner housing (50) contact each other to generate frictional resistance. The method of claim 9, The inner housing 50 includes a main body 50a and a tapered hollow rod 50b that is fitted to the hollow of the main body 50a. The tapered hollow surface of the tapered hollow bar 50b interacts with the tapered portion 42 of the rotary ring 40 to cause frictional resistance, The tapered hollow bar (50b) is a hinge assembly, characterized in that the rubber material of the fluorine or urethane series.