KR101954031B1 - A caster of sofa - Google Patents

Abstract

An objective of the present invention is to easily move a sofa having a high weight so as to improve convenience of use, by providing a configuration that the sofa is freely moved due to characteristics of a spherical shape of a rolling ball without configuring a separate direction switching device. To this end, according to the present invention, a caster provided at a lower end of a sofa to smoothly move the sofa having a high weight includes: a housing (10) formed at one lower end of the sofa, having an accommodation space (12) therein, and having a through-hole (14) having a predetermined size and penetrating the accommodation space (12) on a lower end thereof; a rolling ball (20) inserted into the accommodation space (12) of the housing (10) to allow a lower portion to be partially exposed to the outside through the through-hole (14) so as to support the sofa such that the sofa can be freely moved through a rolling operation; a retainer (30) provided at an upper end of the rolling ball (20) to support the rolling ball (20) such that the rolling ball (20) can be smoothly rotated by minimum contact friction due to point contact with a plurality of balls; and a finishing plate (40) provided at an upper end of the retainer (30) to perform a finishing function to allow the rolling ball (20) and the retainer (30) to smoothly perform the rolling operation.

Description

A caster of sofa configured to allow selective movement of a sofa

The present invention relates to a caster configured to selectively move a sofa, and more particularly, to a caster which is formed at a lower end of a sofa, the caster comprising a housing and an inner side of the housing, A so-called spherical rolling ball configured to be exposed downward, a retainer, and a finishing plate, so that the sofa can be moved in a free direction without constituting a separate direction switching means due to the spherical shape of the rolling ball The present invention relates to a caster configured to be able to selectively move a sofa to easily move a sofa having a high weight and thereby improve convenience of use.

Generally, a sofa is provided with a seat on which a user sits and a backrest that supports a user's seat on the seat, and is usually made up of a sofa for one person and a sofa for a person. In the case of the sofa for one person, And one backrest connected from the four sheets.

In the case of a multi-seat sofa, it is divided into two, three, and four seats according to the number of seats and backrests.

In the case of a sofa for a double seat, for example, a sofa of two seats is composed of two seats in one frame and two backrests connected to the two seats respectively, and in the case of a sofa for three seats, And a seat and three backrests connected to the three seats respectively.

Since the conventional multi-seated sofa is made up of a plurality of seats and a backrest in one frame, it is inconvenient to move, and when the seat arrangement for a sofa in a home is different, There is a problem that it is difficult to move the position of the sofa by weight.

In addition, when the user desires to clean the floor of the sofa as well as the floor of the sofa, it is necessary to move the sofa and move the sofa. The heavy weight of the sofa used in the conventional single frame causes the user to feel uncomfortable There is a problem.

In addition, when a sofa of a heavy weight is forcibly moved, there is a problem that damage such as tearing of a floor plate laid on the floor surface occurs.

In addition, the conventional sofa can be used without being moved when it is placed in a room. However, it is also possible to perform an auxiliary function of feeling comfort by raising the user's legs of the sofa, So that a sofa can be moved and functions as a sofa.

However, the conventional sub sofa also has a problem in that it is not easy to move a woman or a senior citizen who is weaker in strength than an adult so that the weight of the sub sofa is lower than that of a sofa configured as a multi-seat sole.

Registered Utility Model No. 20-485004 of Korea Register (Announcement of Nov. 17, 2017) Registered Utility Model No. 20-476708 of the Republic of Korea (Announcement of March 23, 2015) Korean Patent Publication No. 10-1677877 (published on Nov. 18, 2016)

SUMMARY OF THE INVENTION It is an object of the present invention to provide a caster on one side of a lower portion of a sofa, the caster being formed on the inside of the housing and the housing, And the retainer and the finishing plate constituted by the spherical rolling balls constituted so as to constitute the soccer ball so that the sofa can be moved in the free direction without constituting a separate direction switching means due to the characteristics of the spherical shape of the rolling ball, So that it is possible to selectively move the sofa so as to improve the convenience of use.

According to another aspect of the present invention, there is provided a caster which is disposed at a lower end of a sofa and smoothly moves relative to a sofa with a high load, the caster comprising a lower end of the sofa, A housing having a through hole having a predetermined size penetrating the accommodation space; A cloud ball inserted into the housing space and supporting a part of the lower portion of the housing to the outside through the through hole to freely move the sofa through the rolling action; A retainer formed at an upper end of the rolling ball to support the rolling ball so that the rolling ball can be smoothly rotated by a minimum contact friction due to point contact with the plurality of balls; And a finishing plate formed at the upper end of the retainer and performing a finishing function to smoothly perform the rolling action between the rolling ball and the retainer.

In the present invention, the casters include elevating means for supporting the rolling balls so that the rolling balls are selectively exposed or recessed downwardly of the housing, so that the moving or position fixing of the sofa is selectively performed; A plurality of fixed positions constituted by a first latch having an inclined face at a predetermined angle at a lower end and a second latch having an inclined face at a predetermined angle formed on one side of the first latch, And a guiding part constituted by a lifting space formed in a spaced apart space; The elevating means includes a rotation cam formed in the housing space of the housing, a lift cam positioned at the upper end of the rotation cam and fixed to one side of the sofa, and a first spring configured between the housing and the rotation cam ; Wherein the rotation cam has a rolling ball on the inner side, a retainer and a finishing plate on the inner side, a plurality of moving levers for forming a third latch having a predetermined angled slope on the upper end thereof are spaced apart from each other at a predetermined angle, The ascending / descending cam preferably includes an ascending / descending cam formed at the lower end, and at least one ascending / descending protrusion supporting the outer periphery of the ascending / descending cam so as to be raised and lowered when guided along the ascending / descending space.

In the present invention, the upper end of the housing includes a step portion; Wherein the elevating cam includes a step groove in which a step of the housing is inserted to support the elevating cam and the housing to maintain the engaged relationship; And a second spring formed between the bottom of the sofa and the housing.

In the present invention, the coating layer is formed to have a predetermined thickness on the outer circumference of the rolling ball, and the coating layer has a predetermined thickness to prevent the bottom surface from being damaged by the rolling ball when the sofa is moved; And an absorbent pad formed of the same material as the coating layer on the lower end of the housing.

According to the present invention, there is provided a caster on one side of a lower end of a sofa, the caster being constituted by a housing and a spherical rolling ball constituted by the inside of the housing and a lower part of which is exposed under the housing, So that the sofa can be moved in a free direction without constituting a separate direction switching means by the characteristics of the spherical shape of the rolling ball, so that a sofa of a high weight can be moved easily, .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an image of a sofa on which a caster is mounted according to a first embodiment of the present invention; FIG.
2 is a partially enlarged cross-sectional view of a sofa on which a caster is mounted according to the first embodiment of the present invention;
3 is an exploded perspective view of a caster according to a second embodiment of the present invention;
4 is an assembled cross-sectional view of a caster according to a second embodiment of the present invention,
4a is a state in which the cloud ball is exposed to the outside, and 4b is a state in which the cloud ball is recessed inside the housing.
5 is an operational state diagram of the elevating means according to the second embodiment of the present invention,
5a is the initial state in which the cloud ball is exposed to the outside of the housing.
5b is a state in which the lifting cam descends and comes into close contact with the rotation cam.
5c is a state in which the rotation cam partially rotates by the descended elevation cam.
5d is a state in which the pivoting cam is rotated by a fixed position while the lowered pivoting cam is raised by the first spring.
5e is a state in which the engagement ball of the raised rotation cam is in close contact with the fixed point, and the ball is depressed while being ascended.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

≪ Embodiment 1 >

As shown in Figs. 1 and 2, the caster of the first embodiment is configured at the lower end of a sofa so that anyone can easily move a sofa of a high weight, thereby improving convenience of use. In this case, the sofa is configured not only as a sofa for a single occupant or a multi-occupancy but also as an auxiliary sofa, so that the user can arbitrarily move the auxiliary sofa arbitrarily so as to improve the convenience of use of the auxiliary sofa .

The casters include a housing 10, a rolling ball 20, a retainer 30, and a finishing plate 40.

The housing 10 is fixed at one end to the lower end of the sofa, that is, the auxiliary sofa.

A receiving space 12 is formed in the housing 10 to accommodate the rolling ball 20, the retainer 30, and the finishing plate 40.

A through hole 14 is formed in the lower end of the housing 10 to expose a part of the lower part of the rolling ball 20 received in the receiving space 12.

In this case, it is preferable that the housing 10 is fixed to the sofa such that only a part of the rolling ball 20 accommodated in the accommodation space 12 exposes only the lower end of the sofa.

The cloud ball 20 is received in the housing space of the housing 10 so that a part of the cloud ball 20 is exposed downward through the through hole 14 of the housing 10 so that the sofa is moved as it is in direct contact with the ground surface. Performs the cloud function.

In addition, the rolling ball 20 has a spherical shape, so that when the user pushes the sofa at a desired position without constructing another direction switching means, the ball ball 20 is naturally turned by the sphericity characteristic.

The ball 20 is received in the receiving space 12 of the housing 10 and then the center of the ball is received in the receiving space 12 of the housing 10 when the downward portion is exposed to the outside through the through- So that the rolling ball 20 is naturally positioned in the receiving space 12 of the housing 10 and is prevented from being arbitrarily disengaged through the through hole 14. [

In addition, it is preferable that the rolling ball 20 is made of a metallic material so as to prevent the ball 20 from being damaged due to its own weight.

In this case, the rolling ball 20 includes a coating layer 22 of a certain thickness on the outer periphery to prevent the bottom surface from being damaged due to the material, that is, the property of the metal.

The coating layer 22 is preferably a polyurea. Of course, the present invention is not limited to this, and may be composed of a synthetic resin such as urethane or silicone, which prevents the bottom surface from being damaged when the rolling ball 20 rolls.

The polyurea resin composition of the coating layer 22 is prepared by mixing the prepolymer A and the chain extender B at a volume ratio of 1: 1, and by using the B chain extender (DMTDA, DETDA) Time adjustment can be used to obtain a cure delay effect.

The A agent includes 15-16 parts by weight of a methylene diisocyanate prepolymer which induces a reaction with an amine mixture.

The methylene diisocyanate (MDI) prepolymer is prepared by treating phosgene with diphenylmethanediamine (MDA) produced by condensation of aniline and formaldehyde, and purifying the resulting product through distillation or crystallization.

The methylene diisocyanate provides an additional function to the performance of elasticity. If the amount is less than 15 parts by weight, no additional effect of smooth performance can be expected. If the amount exceeds 16 parts by weight, the performance is maintained. However, There is a problem to raise.

The B agent reacts with the A agent to control the initial curing reaction so that the coating layer 22 is smoothly formed on the outer circumference of the rolling ball 20.

The agent B is prepared by mixing 60 to 61 parts by weight of polyoxypropylenediamine, 18 to 21 parts by weight of diethyltoluene diamine, 2 to 3 parts by weight of dialkylaminodiphenylmethane, 7 to 12 parts by weight of aspartic ester, and 4 To 6 parts by weight of polyether triamine, 0.1 to 0.3 parts by weight of triphenyl phosphate, and 0.05 to 0.1 part by weight of an adhesion promoting agent.

The polyoxypropylenediamine (POLY (OXYPROPYLENE) DIAMINE) is a poly (oxy-methyl-1,2-ethanediyl), alpha- (2-aminomethylethyl) .

The molecular weight of the polyoxypropylene diamine may be 400 to 4,000.

In this case, if the content of the polyoxypropylene diamine is more than 61 parts by weight, the tensile strength and hardness may be lowered, and if it is less than 60 parts by weight, the required tensile strength and hardness can not be obtained.

The diethyltoluenediamine (DETDA) functions as a chain extender to increase the degree of crosslinking of the polyurea, and may be used as an intermediate in organic synthesis as the case may be.

When the content of diethyltoluenediamine is less than 18 parts by weight, the tensile strength and hardness can not be obtained. When the content of diethyltoluenediamine is more than 21 parts by weight, the tensile strength and hardness are increased but the gel time and the pot life are decreased.

The dimethyltoluenediamine (DMTDA) functions as a chain extender to increase the degree of crosslinking of the polyurea and regulates Gel time with a relatively slow reaction.

When the amount of the dimethyltoluenediamine is less than 2 parts by weight, the tensile strength and hardness can not be obtained. When the amount of the dimethyltoluenediamine exceeds 5 parts by weight, the viscosity of the agent B is increased, and when the reaction is conducted at a ratio of the agent A, .

The dialkylaminodiphenylmethane functions to increase the degree of crosslinking of the polyurea.

If the content of the dialkylaminodiphenylmethane is less than 2 parts by weight, a desired viscosity can not be obtained and the degree of crosslinking is deteriorated. When the amount is more than 3 parts by weight, the viscosity of the solution excessively increases.

The aspartic ester controls the pot life of the polyurea.

The aspartic ester is a Polayspartic ester resin.

If the content of the aspartic ester is less than 7 parts by weight, the controlling function of the pot life is insignificant, and if it exceeds 12 parts by weight, the tensile strength and hardness are lowered.

The polyether triamine is used to increase the degree of crosslinking of the polyurea and to control the curing time.

Further, the molecular weight of the polyether triamine may be 400 to 5,000.

When the amount of the polyether triamine is less than 4 parts by weight, the curing time control function is insignificant. When the amount is more than 6 parts by weight, the trifunctional cross-linking degree is increased and the elongation is decreased.

The triphenyl phosphate (TPP) functions as a heat stabilizer and an antioxidant.

If the amount of the triphenyl phosphate is less than 0.1 part by weight, the function of the heat stabilizer and the antioxidant is insufficient. If the amount of triphenyl phosphate is more than 0.3 part by weight, the heat stabilizer and the antioxidant function are not affected, .

The adhesion promoter performs a function of enhancing adhesion.

The adhesion promoter may be a silane coupling agent.

If the content of the adhesion promoter is less than 0.05 part by weight, adhesion performance is not exhibited. If the amount is more than 0.1 part by weight, the silane component may be broken and adhesion may be lowered.

The coating layer 22 is formed to have a thickness of 0.1 to 1 mm on the outer circumferential edge of the rolling ball 20.

The retainer 30 is seated on the upper end of the rolling ball 20 to support the rolling ball 20 so that the rolling ball 20 can rotate smoothly.

The retainer (30) is composed of a plurality of balls and an interlocking band for restraining the plurality of balls from being displaced.

That is, since the retainer 30 has the same structure and function as the retainer formed in the ball bearing, the detailed structure and operation will not be described here.

The finishing plate 40 is inserted into the accommodating space 12 of the housing 10 and seated on the upper end of the retainer 30 to provide a fixing force so that the function of the retainer 30 can be smoothly performed .

That is, the finishing plate 40 is seated on the upper end of the retainer 30 and is fixed to the inside of the housing 10, so that when the rolling ball 20 is rotated by the retainer 30, So that the retainer (30) arbitrarily supports the upper end of the rolling ball (20).

The caster configured as described above is formed at the lower end of the sofa, that is, the sub sofa, and the rolling ball 20 partially exposed at the lower end of the housing 10 is kept in close contact with the ground, When the rolling ball 20 is in contact with the ground surface, the rolling ball 20 is brought into point contact with the retainer 30 to perform the rolling action, thereby smoothly moving the sofa.

≪ Embodiment 2 >

The same reference numerals are used for the same components as in the first embodiment, and a detailed description thereof will be omitted.

As shown in Figs. 3 to 5, the caster of the second embodiment comprises elevating means 100 for supporting the rolling ball 20 so that the rolling ball 20 can be selectively taken out from the lower end of the sofa, The position is firmly fixed so that the convenience of use on the sofa is further improved.

The elevating means 100 includes a housing 10, a pivotal cam 110 formed inside the housing 10, and a lifting cam 120 disposed above the pivotal cam 110.

The housing 10 has a receiving space 12 formed therein.

A through hole 14 is formed in the lower end of the housing 10 to expose a part of the rolling ball 20.

The inner surface of the housing 10 includes a guide portion 16 for guiding the lifting and lowering of the lifting cam 120 and guiding the lifting and lowering cam 110 to rotate at a predetermined angle.

The guide portion 16 includes a plurality of fixed portions 162.

In addition, the guide portion 16 includes a lifting space 164 formed by the plurality of fixed portions 162 being spaced apart from each other by a predetermined distance.

A first latch 1622 rising at a predetermined height from an end of the first latch 1622 and having an inclination angle equal to or similar to that of the first latch 1622, Lt; RTI ID = 0.0 > 1624 < / RTI >

The fixed portion 162 functions to support the pivotal cam 110 so that the pivotal movement of the pivotal cam 110 can be smoothly performed by rotating the pivotal cam 110 at a predetermined angle.

The lifting and lowering space 164 serves to guide the lifting and lowering of the lifting and lowering cam 120.

When the bottom of the housing 10 is depressed to the inside of the housing 10, when the bottom surface of the housing 10 is brought into close contact with the bottom surface of the housing 10, Absorbing pad 18 of a certain thickness to prevent any movement.

The absorbent pad 18 can be any material that can prevent any movement of the sofa due to shock absorption and frictional force. In this case, the absorbent pad 18 is formed of the same material as that of the coating layer 22 shown in the first embodiment.

The upper end of the housing 10 is provided with a step 19 for supporting the lifting and lowering cam 120 so that the lifting and lowering cam 120 can be lifted smoothly while being coupled with the lifting and lowering cam 120.

The pivotal cam 110 is received in the receiving space 12 of the housing 10 and is rotated by a predetermined angle while lifting and lowering by the force of the lowering force of the lifting cam 120, In order to allow the user to selectively enter and exit the apparatus.

In this case, a caster module including a rolling ball 20, a retainer 30 and a finishing plate 40 is mounted on the inside of the pivotal cam 110.

In addition, the pivotal cam 110 includes at least one movable latch 112 having a predetermined length at an outer circumference and having a predetermined interval.

A third latch 1122 inclined at a slope equal to or similar to the inclination angle of the fixed portion 162 constituted by the guide portion 16 of the housing 10 is formed at the upper end of the movable latch 112. [

A lower portion of the second latch 1624 of the fixed portion 162 formed in the guide portion 16 of the housing 10 is coupled to the lower end of the pivotal cam 110 so as to intermittently ascend the elevation height when the pivotal cam 110 is lifted by the elastic force of the spring. The latching protrusion 114 is formed.

The lifting cam 120 has one end fixed to the lower end of the sofa and the other end accommodated in the accommodation space 12 of the housing 10. When the user presses one side of the sofa, And performs a function of providing a lowering force to lower the cam 110.

The lower end of the elevating cam 120 includes a synchromesh 122 having an inclination angle equal to or similar to the inclination angle of the fixed portion 162 formed in the guide portion 16 of the housing 10 and having a mountain- do.

The lifting and lowering protrusion 124 is positioned on the outer circumference of the lifting cam 120 so as to be guided along the lifting space 164 formed in the guiding portion 16 of the housing 10 do. In this case, the elevating protrusion 124 is preferably positioned below the elevating cam 120.

The stepped portion 19 of the housing 10 is inserted into the outer periphery of the lifting cam 120 and is formed to have a predetermined depth and length so as to smoothly engage with the housing 10 and move up and down And includes a step groove 126. In this case, it is preferable that the step groove 126 is located above the lifting cam 120.

The elevating means 100 includes a first spring 130 for applying an elastic force to the pivotal cam 110 to smoothly rotate the pivotal cam 110 by a predetermined angle.

The first spring 130 is disposed between the housing 10 and the lower end of the rotation cam 110.

The elevating means 100 includes a second spring 140 for preventing the elevating means 100 constructed below the sofa from being subjected to any action due to vibration or impact acting on the sofa.

The second spring 140 is preferably disposed between the lower end of the sofa and the upper end of the housing 10.

The operation state of the elevating means constructed as described above will be described below.

The rolling ball 20 is partially exposed under the housing 10 constituted by the sofa by the lifting means 100. This is a state in which the rolling ball 20 The movable latch 112 is engaged with the lower end of the first latch 1622 at the fixed position 162 formed in the guide portion 16 of the housing 10.

The lower end of the elevating cam 120 is positioned at the upper end of the pivotal cam 110. In this case, the third latch 1122 and the elevating cam 1122, which are formed on the moving latch 112 of the pivotal cam 110, 120 are in contact with each other.

At this time, not the vertexes of the ascending synchronous character 122 formed in the mountain shape but a part of the inclined surfaces forming the inclination angle are in contact with the inclined surfaces forming the inclination angle of the third latch 1122 of the movement rest 112.

The elevation protrusion 124 of the elevation cam 120 is positioned in the elevation space 164 formed in the guide portion 16 of the housing 10.

Since the first spring 130 formed between the housing 10 and the rotation cam 110 is in a state in which the rotation cam 110 is engaged with the guide portion 16 of the housing 10, The first spring 130 is maintained in a compressed state.

When the rolling ball 20 exposed downward is depressed toward the inside of the housing 10, the elevating means 100 presses one side of the constructed sofa.

Thus, the lifting cam 120 fixed to the lower end of the sofa is forcibly lowered.

The lifting and lowering protrusion 124 formed on the outer periphery of the lifting cam 120 is positioned in the lifting and lowering space 164 formed in the guide portion 16 of the housing 10, And is stably lowered.

The rotating cam 110 is rotated by the lower force of the lifting cam 120 in a state in which the rotational synchronizing coefficient 122 of the lifting cam 120 is in contact with the moving let 112 of the rotating cam 110. [ .

At this time, in a state in which the inclined surface of the synchromesh 122 and the inclined surface of the third latch 1122 of the shift lever 112 are kept in close contact with each other, the movable latch 112 of the falling cam 110 slides downward, When the state of being latched by the first latch 1622 of the fixed position 162 formed in the guide portion 16 of the shift lever 112 is released, The slider 1122 slides and the pivotal cam 110 rotates at a predetermined angle.

In this case, the lifting and lowering cam 120 maintains the state where the lifting and lowering projection 124 is positioned in the lifting and lowering space 164 of the guide portion 16, so that the pivoting cam 110 rotates only at a certain angle.

The movement latch 112 of the rotation cam 110 is positioned at a position corresponding to the second latch 1624 at the fixed position 162 as the rotation cam 110 rotates by a predetermined angle.

Then, when the pressing force of the sofa is released, the rotation cam 110 is raised by the elastic return force of the first spring 130 formed between the housing 10 and the rotation cam 110.

At this time, as the movable latch 112 of the ascending rotating cam 110 is brought into close contact with the second latch 1624 formed on the guide portion 16 of the housing 10, The movement latch 112 of the pivotal cam 110 slides along the inclined surface.

In addition, the movable latch 112 is positioned in the ascending / descending space 164 formed between the fixed positions 162 according to the slippage of the second latch 1624, and inserted into the ascending / do.

The elevating cam 120 located above the pivoting cam 110 is raised by the elastic return force of the second spring 140 formed between the lower end of the sofa and the housing 10.

The pivoting cam 110 is lifted so that the latching jaw 114 formed at the lower end of the pivoting cam 110 contacts the first latch 1622 at the fixed position 162 formed in the guide portion 16 of the housing 10 It is raised until it is caught.

The third latch 1122 formed on the movable latch 112 of the raised pivotal cam 110 and the portion of the inclined surface formed on the pivotal engagement portion 122 of the elevation cam 120 are in contact with each other.

Thus, the caster module, that is, the rolling ball 20, the retainer 30, and the finishing plate 40, which are formed inside the pivotal cam 110 by the pivoting cam 110 having a predetermined height, And consequently the cloud ball 20 is recessed into the inside of the housing 10.

When the crane cam 120 is lowered by pushing one side of the sofa as described above, the pivotal cam 110 is moved downward, .

When the movable latch 112 of the pivotal cam 110 is moved out of the vertical space 164 of the guide portion 16, The third latch 1122 of the shift lever 112 slides so that the pivotal cam 110 rotates by a predetermined angle and the shift lever 112 is rotated by the first latch (1622).

Then, when the pressing force is released from the sofa, the rotation cam 110 is lifted by the elastic return force of the first spring 130.

At this time, the third latch 1122 formed on the movement latch 112 of the pivotal cam 110 slides along the sloped surface of the first latch 1622 of the guide portion 16 and rotates to the first latch 1622 The rolling ball 20 of the caster module formed inside the pivotal cam 110 is partially exposed through the through hole 14 of the housing 10 by keeping the movement latch 112 of the cam 110 in the locked state, So that the sofa can be freely moved.

Therefore, as the rolling balls formed inside the pivot cam are selectively exposed or depressed downwardly of the housing by the action of the elevating cam and the pivoting cam being forcibly lowered, the female or elderly person can easily lift the sofa Thereby improving the convenience of use.

The above description is only one embodiment for implementing a lightweight panel manufacturing apparatus for manufacturing a caster configured to selectively move a sofa, and the present invention is not limited to the above embodiment. It will be understood by those skilled in the art that various changes may be made without departing from the spirit of the invention.

10: housing 12: accommodation space
14: through hole 16: guide portion
162: fixed 1622: first leg
1624: second latch 164: ascending / descending space
18: Absorption pad 19:
20: cloud ball 22: coating layer
30: retainer 40: finishing plate
100: elevating means 110:
112: Moving Latch 1122: Third Latch
114: engaging jaw 120: lifting cam
122: synchromesh 124: elevation projection
126: step groove 130: first spring
140: second spring

Claims (4)

A housing 10 formed at a lower end of the sofa and having a housing space 12 formed at an inner side thereof and a through hole 14 formed at a lower end thereof with a predetermined size passing through the housing space 12; A cloud ball 20 inserted into the accommodation space 12 and supporting a part of the lower portion of the cloud ball 20 to be exposed to the outside through the through hole 14 to freely move the sofa through the rolling action; A retainer (30) formed at an upper end of the retainer (30) for supporting the rolling ball (20) smoothly rotated by a minimum contact friction due to point contact with a plurality of balls, And a finishing plate (40) that performs a finishing function by which the rolling ball (20) and the retainer (30) can smoothly perform a rolling action, so as to easily move the sofa,
The caster includes lifting means (100) for supporting the rolling balls (20) to be selectively exposed or depressed downwardly of the housing (10) so that movement or position fixing of the sofa is selectively performed;
A plurality of first latches 1620 are formed on the inner side of the housing 10 so as to form a first latch 1622 having a slope at a predetermined angle at a lower end thereof and a second latch 1624 sloped at a predetermined angle at one side of the first latch 1622 A guide portion 16 constituted by a fixed portion 162 and an elevated space 164 formed in a space in which the plurality of fixed portions 162 are spaced apart from each other by a predetermined distance; A pad 18, and a step 19 formed at the upper end;
The elevating means 100 includes a pivoting cam 110 formed in the receiving space 12 of the housing 10 and a lifting cam 120 positioned at the upper end of the pivoting cam 110 and fixed to one side of the sofa A first spring 130 formed between the housing 10 and the rotation cam 110 and a second spring 140 formed between the bottom of the sofa and the housing 10;
The pivotal cam 110 includes a rolling ball 20, a retainer 30 and a finishing plate 40 on the inner side and a movable latch 112 (see FIG. 1) in which a third latch 1122 having an inclined surface at a predetermined angle is formed, Are formed at a predetermined angle apart from each other, and a locking protrusion 114 is formed at a lower end thereof;
The ascending / descending cam 120 includes an ascending / descending cam 122 formed at the lower end thereof, at least one ascending / descending protrusion 124 for supporting the outer periphery of the ascending and descending cam when it is guided along the lifting and lowering space 164, And a step groove (126) for inserting the step portion (19) of the housing (10) to support the lifting cam (120) and the housing (10)
And a coating layer (22) having a predetermined thickness for preventing the bottom surface from being damaged by the rolling ball (20) of metallic material when the sofa is moved, on the outer circumference of the rolling ball (20)
The coating layer 22 and the absorbent pad 18 are composed of a polyurea resin;
The polyurea resin composition is prepared by mixing the prepolymer A and the chain extender B in a weight ratio of 1: 1;
The agent B is prepared by mixing 60 to 61 parts by weight of polyoxypropylenediamine, 18 to 21 parts by weight of diethyltoluene diamine, 2 to 3 parts by weight of dialkylaminodiphenylmethane, 7 to 12 parts by weight of aspartic ester, and 4 To 6 parts by weight of polyether triamine, 0.1 to 0.3 parts by weight of triphenyl phosphate, and 0.05 to 0.1 parts by weight of an adhesion promoter;
And a caster for selectively moving the sofa. delete delete delete

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