Roller unit having integrated fastening portion

A roller unit having an integrated fastening portion includes a supporting shaft fastened to a containing body or a containing main body that can slide and having first and second flanges formed in multi steps with different outer diameters, a rotating body rotatably fixed to a side of the supporting shaft, and a washer coupled to a side of the rotating body to surround and fix the second flange, thereby preventing separation of the supporting shaft and the rotating body. Therefore, it is possible to more conveniently combine the supporting shaft and the rotating body and to prevent separation of the supporting shaft and the rotating body, whereby is possible to improve various functions.

This application claims benefit under 35 U.S.C. 119(e), 120, 121, or 365(c), and is a National Stage entry from International Application No. PCT/KR2015/000902, filed Jan. 28, 2015, which claims priority to the benefit of Korean Patent Application No. 10-2014-0011076 filed on Jan. 29, 2014, 10-2014-0011077 filed on Jan. 29, 2014, and 10-2014-0169889 filed on Dec. 1, 2014 in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference.

The present invention relates to a roller unit having an integrated fastening portion. More particularly, the present invention relates to a roller unit having an integrated fastening portion. The roller unit includes: a supporting shaft fastened to a containing body or a containing main body that can slide, and having first and second flanges formed in multi steps with different outer diameters; a rotating body rotatably fixed to a side of the supporting shaft; and a washer coupled to a side of the rotating body to surround and fix the second flange, thereby preventing separation of the supporting shaft and the rotating body, or includes: a supporting shaft fastened to a containing body or a containing main body that can slide and having first and second flanges formed in multi steps with different outer diameters; and a rotating body having a fixing portion surrounding the second flange of the supporting shaft, or includes: a supporting shaft having first and second flanges having different outer diameters and fastened to a containing body or a containing main body that can slide; a roller rotatably coupled to a side of the supporting shaft; and a fixing body coupled to the coupling portions by coupling protrusions formed at positions corresponding to the coupling portions, thereby retaining the supporting shaft and the roller. Therefore, it is possible to more conveniently combine the supporting shaft and the rotating body, or the supporting shaft and the roller, and prevent separation of the supporting shaft and the rotating body, or the supporting shaft and the roller, whereby it is possible to improve various functions.

BACKGROUND ART

In general, a roller unit, which is a part having a cylindrical wheel rotatably coupled to a fastening member to reduce frictional resistance by changing sliding friction that is generated in sliding into roller friction, is applied in various fields to various products including furniture or a refrigerator having slidable containing bodies so that a user can smoothly open and close the containing bodies.

A roller unit according to the related art disclosed in Korean Patent No. 10-0822749 includes a wheel (rotary body), a support shaft, and a retainer coupled to a mounting portion of the support shaft to hold the wheel.

However, the roller unit disclosed in Korean Patent No. 10-0822749 necessarily requires a specific retainer for preventing separation of the wheel and the support shaft, so the manufacturing cost is high.

Further, the roller unit has a problem in that the wheel and the support shaft are separated due to corrosion at the portion plastically deformed for coupling the wheel and the support shaft.

There are Korean Patent Nos. 10-0841057 and 10-0654951 as prior art documents relating to such a roller unit.

SUMMARY

The present invention has been made in an effort to solve the problem and an object of the present invention is to provide a roller unit having an integrated fastening portion. The roller unit includes: a supporting shaft fastened to a containing body or a containing main body that can slide, and having first and second flanges formed in multi steps with different outer diameters; a rotating body rotatably fixed to a side of the supporting shaft; and a washer coupled to a side of the rotating body to surround and fix the second flange, thereby preventing separation of the supporting shaft and the rotating body, or includes: a supporting shaft fastened to a containing body or a containing main body that can slide and having first and second flanges formed in multi steps with different outer diameters; and a rotating body having a fixing portion surrounding the second flange of the supporting shaft, or includes: a supporting shaft having first and second flanges having different outer diameters and fastened to a containing body or a containing main body that can slide; a roller rotatably coupled to a side of the supporting shaft; and a fixing body coupled to the coupling portions by coupling protrusions formed at positions corresponding to the coupling portions, thereby retaining the supporting shaft and the roller. Therefore, it is possible to more conveniently combine the supporting shaft and the rotating body, or the supporting shaft and the roller, and prevent separation of the supporting shaft and the rotating body, or the supporting shaft and the roller, whereby it is possible to improve various functions.

A roller unit having an integrated fastening portion according to a first embodiment of the present invention includes: a supporting shaft having a first flange fastened to a containing body or a containing main body that can slide, formed in multi steps, and being in contact with the containing body or the containing main body, and a second flange having an outer diameter different from an outer diameter of the first flange and coupled to a rotating body by a washer; the rotating body rotatably coupled to a side of the supporting shaft and having a fixing groove for fixing the washer in a coupling direction of the supporting shaft; and the washer coupled to a side of the rotating body to surround and fix the second flange and having an insertion protrusion fitted in the fixing groove to surround the second flange, thereby preventing separation of the supporting shaft and the rotating body by retaining the supporting shaft and the rotating body.

The supporting shaft may have: a fastening portion having a predetermined length; the first flange disposed at a side of the fastening portion and being in contact with the containing body or the containing main body; the second flange making a single body with the first flange, having an outer diameter larger than an outer diameter of the first flange, and coupled to the rotating body by the washer; and the supporting portion protruding toward the rotating body at a side of the second flange and fitted in a hollow portion of the rotating body.

The rotating body may have: a hollow portion formed through a center of the rotating body; a supporting step formed at an end of the hollow portion in a coupling direction of the supporting shaft and supporting a surface, which faces the hollow portion, of the second flange; and the fixing groove formed at the supporting step and recessed in the coupling direction of the supporting shaft to fix the washer, in which the fixing groove has an inner diameter larger than the inner diameter of an opening.

A reinforcing groove recessed toward the hollow portion may be formed around an outer side of the rotating body, and a ring-shaped reinforcing member for preventing sliding and noise may be fitted in the reinforcing groove.

The washer may have: the insertion protrusion fitted in the fixing groove; a supporting protrusion protruding outward close to the insertion protrusion and having a surface, which faces the rotating body, being in contact with the supporting step; and a fixing portion bending inward toward the hollow portion at an opposite side to the supporting protrusion and having a fixing protrusion forming a receiving groove for fixing the second flange therein, in which the insertion protrusion may be fitted in the fixing groove with the second flange received in the receiving groove to prevent separation of the supporting shaft and the rotating body.

A roller unit having an integrated fastening portion according to a second embodiment of the present invention includes: a supporting shaft fastened to a containing body or a containing main body that can slide and having first and second flanges formed in multi steps with different outer diameters; and a rotating body having a fixing portion surrounding the second flange of the supporting shaft.

The supporting shaft may have: a fastening portion having a predetermined length; the first flange disposed at a side of the fastening portion and being in contact with the containing body or the containing main body; the second flange making a single body with the first flange, having an outer diameter larger than an outer diameter of the first flange, and coupled to the rotating body by the fixing portion; and the supporting portion protruding toward the rotating body at a side of the second flange and fitted in a hollow portion of the rotating body.

The rotating body may have: a hollow portion formed through a center of the rotating body; a supporting step formed at an end of the hollow portion in a coupling direction of the supporting shaft and supporting a surface, which faces the hollow portion, of the second flange; and fixing portions arranged around the hollow portion, ramified with regular intervals, and having a fixing protrusion bending toward the hollow portion at an end and forming a receiving groove for fixing the second flange therein.

A reinforcing groove recessed toward the hollow portion may be formed around an outer side of the rotating body, and a ring-shaped reinforcing member may be fitted in the reinforcing groove.

A roller unit having an integrated fastening portion according to a third embodiment of the present invention includes: a supporting shaft having first and second flanges formed in multi steps with different outer diameters to be fastened to a containing body or a containing main body that can slide; a roller rotatably coupled to a side of the supporting shaft and having coupling portions formed in a fastening direction with regular intervals therein; and a fixing body coupled to a side of the roller to surround and fix the second flange of the supporting shaft and coupled to the coupling portions by coupling protrusions formed at positions corresponding to the coupling portions, thereby retaining the supporting shaft and the roller.

The supporting shaft may have: a fastening portion having a predetermined length, fastened to the containing body or the containing main body, and having a thread around an outer side; the first flange formed at a side of the fastening portion and being in contact with the containing body or the containing main body; the second flange making a single body with the first flange, having an outer diameter larger than an outer diameter of the first flange, and coupled to the roller by the coupling portions; and a supporting protrusion protruding toward the roller at a side of the second flange and fitted in a hollow portion of the roller.

A tool groove may be further formed at an end of the supporting portion.

The roller may have: a hollow portion formed through a center of the roller; a supporting step formed on an outer side of an end of the hollow portion in a coupling direction of the supporting shaft and supporting a surface, which faces the hollow portion, of the second flange; and coupling portions formed outside the hollow portion and having a coupling hole for receiving the coupling protrusion of the fixing body, and the coupling portions may have: coupling holes arranged around the hollow portion, ramified with regular intervals, and receiving the coupling protrusions of the fixing body; and fixing protrusions protruding inward in the coupling holes, providing a fixing space for the coupling protrusions of the fixing body inserted in the coupling holes, having a fixing step preventing separation of the coupling protrusions and an inclined coupling guide curvedly formed at an end in a coupling direction of the supporting shaft and guiding the coupling protrusions to be coupled.

The fixing body may have: a flange supporting portion having a flange hole formed at a center thereon and receiving the first flange of the supporting shaft, and a flange seat recessed on a side of the flange hole so that the second flange of the supporting shaft is seated therein; and the coupling protrusions formed on a surface, which faces the roller, of the flange supporting portion, at the same positions and in the same numbers as the coupling holes of the roller, and inserted and locked by a fixing step in the coupling holes of the roller, thereby retaining the roller and the supporting shaft.

A fitting groove recessed toward the hollow portion may be formed around an outer side of the rotating body, and a ring-shaped rotation-assistant member may be fitted in the fitting groove.

As described above, a roller unit having an integrated fastening portion according to the present invention includes: a supporting shaft fastened to a containing body or a containing main body that can slide, and having first and second flanges formed in multi steps with different outer diameters; a rotating body rotatably fixed to a side of the supporting shaft; and a washer coupled to a side of the rotating body to surround and fix the second flange, thereby preventing separation of the supporting shaft and the rotating body, or includes: a supporting shaft fastened to a containing body or a containing main body that can slide and having first and second flanges formed in multi steps with different outer diameters; and a rotating body having a fixing portion surrounding the second flange of the supporting shaft, or includes: a supporting shaft having first and second flanges having different outer diameters and fastened to a containing body or a containing main body that can slide; a roller rotatably coupled to a side of the supporting shaft; and a fixing body coupled to the coupling portions by coupling protrusions formed at positions corresponding to the coupling portions, thereby retaining the supporting shaft and the roller. Therefore, it is possible to more conveniently combine the supporting shaft and the rotating body, or the supporting shaft and the roller, and prevent separation of the supporting shaft and the rotating body, or the supporting shaft and the roller, whereby it is possible to improve various functions.

DETAILED DESCRIPTION

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings showing embodiments of the present invention for those skilled in the art to easily achieve the present invention. Unless specifically defined, terminologies used herein have the same meanings as corresponding terminologies that those skilled in the art understand. If the meanings of terminologies used herein conflict with common meanings of corresponding terminologies, they follow the definition made herein, and like reference numerals used herein indicate the same components.

Further, a roller unit having an integrated fastening portion disclosed herein can be achieved in various embodiments, but it should be understood that the roller unit having an integrated fastening portion is not limited to the embodiments.

First Embodiment

A roller unit100having an integrated fastening portion according to a first embodiment of the present invention includes: a support shaft110having first and second flanges112and114fastened to a containing body or a containing main body (hereafter, referred to as a mounting structure); a rotating body120rotatably coupled to a side of the support shaft110; and a washer130surrounding the second flange114and coupled to a side of the rotating body120.

The mounting structure102, which means a containing body for keeping for use necessary articles or a containing main body for accommodating the containing body, can be applied to various products such as furniture or a refrigerator.

The supporting shaft110has the first and second flanges112and114that are stepped and is fastened to the mounting structure102such as furniture of a refrigerator.

The supporting shaft110has a fastening portion111, the first flange112formed at a side of the fastening portion111, a second flange114having a larger outer diameter than the first flange112, and a supporting portion116protruding at a side of the second flange114.

The fastening portion111extends a predetermined length and is fastened to the mounting structure102.

The fastening portion111can be fastened in a thread-fastening type by forming a thread111alongitudinally around the outer side, or may be fastened in various ways such as forcible fitting.

A contact surface112athat is in close contact with the mounting structure102is formed at the side, which faces the mounting structure102, of the first flange112.

The contact surface112amay be formed in a shape corresponding to the mounting structure102that the contact surface112afaces.

For example, when the portion of the mounting structure102that the contact surface112faces is flat, the contact surface112ais made flat, and when it is uneven, the contact surface112ais also made uneven for close contact to prevent the thread-fastened fastening portion111from loosening.

The second flange114is formed on one body with the first flange112, but may have an outer diameter different from that of the first flange112.

For example, the second flange114is formed to have an outer diameter D2alarger than the diameter D1aof the first flange112.

The reason of making the outer diameter D2aof the second flange114larger than the outer diameter D1aof the first flange112is for coupling the supporting shaft110to the rotating body120through a fixing portion136of the washer130with the second flange114therebetween unlike the first flange112being in contact with the mounting structure102.

The supporting portion116protrudes toward the rotating body120, at a side of the second flange114.

The outer diameter D3aof the supporting portion116is made a little smaller than the inner diameter D4aof a hollow portion121of the rotating body120so that the supporting portion116can be easily inserted into the hollow portion121.

The outer side of the supporting portion116has a shape corresponding to the shape of the hollow portion121of the rotating body120.

An end of the support portion116may be chamfered to be smoothly inserted into the hollow portion121of the rotating body120.

A tool groove116amay be formed at the end of the supporting portion116in various shapes such as “+”, “−”, and “★” corresponding to fastening tools so that the roller unit100can be easily and conveniently fastened to the mounting structure102by the fastening tools.

The rotating body120is rotatably coupled to a side of the supporting shaft110and has the hollow portion121, a supporting step122formed outside the end of the hollow portion121, and a fixing groove123formed at the supporting step122.

The hollow portion121is formed axially through the center of the rotating body120so that the supporting shaft110is inserted therein.

The supporting step122is disposed outside the end of the hollow portion121in the insertion direction of the supporting shaft110and supports the side, which faces the hollow portion121, of the second flange114.

The fixing groove123is recessed in the insertion direction of the supporting shaft110on a side of the supporting step122and fixes the washer130.

The inner diameter D5aof the fixing groove123may be made larger than the inner diameter D6aof an opening124to prevent an inserting protrusion132of the washer130from separating outside.

A reinforcing groove125recessed toward the hollow portion121may be further formed around the outer side of the rotating body120having this configuration.

The reinforcing groove125has a ring-shaped cross-section and a ring-shaped reinforcing member126is seated in the reinforcing groove125.

The reinforcing member126may be made of urethane that can prevent sliding and noise in a rotational motion.

The washer130, which has a hole at the center and surrounds the second flange114, is coupled to a side of the rotating body120and retains the supporting shaft110and the rotating body120to prevent separation of them.

The washer130has an insertion protrusion132fitted in the fixing groove123, a supporting protrusion134protruding outward close to the insertion protrusion132, and a fixing portion136formed opposite to the supporting protrusion134.

The insertion protrusion132protrudes toward the rotating body120, has a shape corresponding to the fixing groove123, and is fitted in the fixing groove123.

The supporting protrusion134protrudes outward close to the insertion protrusion132, and a side of the supporting protrusion134which faces the rotating body120is in contact with the supporting step122when the insertion protrusion132is fitted in the fixing groove123.

The fixing portion136has a fixing protrusion136abending inward toward the hollow portion121at the opposite side to the supporting protrusion134.

The fixing protrusion136aforms a receiving groove136bfor fixing the second flange114therein by bending toward the hollow portion121.

For example, in order to fit the insertion protrusion132of the washer130in the fixing groove123of the rotating body120, the fixing protrusion136aforms the substantially U-shaped receiving groove136bbetween the fixing protrusion and the supporting step122of the rotating body120, whereby the second flange114is fixed in the receiving groove136b.

Accordingly, separation of the supporting shaft110and the rotating body120coupled by the washer130can be prevented.

In order to fit the second flange114of the supporting shaft110in the receiving groove136bof the fixing protrusion136aof the washer130, an end120aof the rotating body120and an end of the first flange112are spaced at a predetermined gap T1from each other so that the rotating body120can smoothly rotate without interference by the mounting structure102such as a containing body or a containing main body.

A process of assembling the roller unit100having an integrated fastening portion according to the first embodiment of the present invention is described hereafter.

First, the supporting shaft110and the rotating body120, which are mounted on the mounting structure102such as a containing body or a containing main body and can be combined in an integrated unit to reduce friction resistance by changing sliding friction into rolling friction while the containing body is opened and closed, are prepared.

The supporting portion116protruding at a side of the second flange114of the supporting shaft110is placed parallel with the hollow portion121of the rotating body120to be inserted therein in order to combine the supporting shaft110and the rotating body120.

As described above, with the supporting portion116of the supporting shaft110and the hollow portion121of the rotating body120arranged in parallel with each other, by inserting the supporting shaft110into the rotating body120, the supporting portion116of the supporting shaft110can be fitted in the hollow portion121of the rotating body120.

After the supporting portion116of the supporting shaft110is fitted in the hollow portion121of the rotating body120, the supporting shaft110and the rotating body120is coupled by the washer130.

In this process, a side of the second flange114of the supporting shaft110is brought in contact with the supporting step122of the rotating body120, the second flange114of the supporting shaft110is inserted into the receiving groove136bformed by the fixing protrusion136aof the washer130, and the insertion protrusion132is fitted into the fixing groove123of the rotating body120.

The insertion protrusion132of the washer130may be forcibly fitted into the fixing groove123of the rotating body120by a pushing device and can be firmly fixed without separating by the insertion protrusion132having a shape corresponding to the inner diameter D5aof the fixing groove123that is larger than the inner diameter D6aof the opening124.

By this process, the roller unit100having an integrated fastening portion according to the first embodiment of the present invention can be fastened to the mounting structure102to be used by inserting a fastening tool into the tool groove116aand then turning the supporting shaft110for thread-fastening.

The roller unit100having an integrated fastening portion according to the first embodiment of the present invention includes: the supporting shaft110having the first and second flanges112and114formed in multi steps with different outer diameters to be fastened to a containing body or a containing main body that can slide; the rotating body120rotatably coupled to a side of the supporting shaft110; and the washer130surrounding and fixing the second flange114, coupled to a side of the rotating body120, and preventing separation of the supporting shaft110and the rotating body120. Therefore, it is possible to more conveniently combine the supporting shaft110and the rotating body120and prevent separation of the supporting shaft110and the rotating body120, whereby it is possible to improve various functions.

Second Embodiment

A roller unit200having an integrated fastening portion according to a second embodiment of the present invention includes: a support shaft210having first and second flanges214and216fastened to a containing body or a containing main body (hereafter, referred to as a mounting structure); and a rotating body220having fixing portions226surrounding the second flange216of the supporting shaft210.

The mounting structure202, which means a containing body for keeping for use necessary articles or a containing main body for accommodating the containing body, can be applied to various products such as furniture or a refrigerator.

The supporting shaft210has the first and second flanges214and216that are stepped and is fastened to the mounting structure202such as furniture or a refrigerator.

The supporting shaft210has a fastening portion212, the first flange214formed at a side of the fastening portion212, a second flange216having a larger outer diameter than the first flange214, and a supporting portion218protruding at a side of the second flange216.

The fastening portion212extends a predetermined length and is fastened to the mounting structure202.

The fastening portion212can be fastened in a thread-fastening type by forming a thread212alongitudinally around the outer side, or may be fastened in various ways such as forcible fitting.

A contact surface214athat is in close contact with the mounting structure202is formed at the side, which faces the mounting structure202, of the first flange214.

The contact surface214amay be formed in a shape corresponding to the mounting structure202that the contact surface214afaces.

For example, when the portion of the mounting structure202that the contact surface212faces is flat, the contact surface214ais made flat, and when it is uneven, the contact surface214ais also made uneven for close contact to prevent the thread-fastened fastening portion212from loosening.

The second flange216is formed on one body with the first flange214, but may have an outer diameter different from that of the first flange214.

For example, the second flange216is formed to have an outer diameter D2blarger than the diameter D1bof the first flange214.

The reason of making the outer diameter D2bof the second flange216larger than the outer diameter D1bof the first flange214is for coupling the supporting shaft210to the rotating body220through the fixing portions226with the second flange216therebetween unlike the first flange214being in contact with the mounting structure202.

The supporting portion218protrudes toward the rotating body220, at a side of the second flange216.

The outer diameter D3bof the supporting portion218is made a little smaller than the inner diameter D4bof a hollow portion220of the rotating body222so that the supporting portion218can be easily inserted into the hollow portion222.

The outer side of the supporting portion218has a shape corresponding to the shape of the hollow portion222of the rotating body220.

An end of the support portion218may be chamfered to be smoothly inserted into the hollow portion222of the rotating body220.

A tool groove218amay be formed at the end of the supporting portion218in various shapes such as “+”, “−”, and “★” corresponding to fastening tools so that the roller unit200can be easily and conveniently fastened to the mounting structure202by the fastening tools.

The rotating body220has the hollow portion222, the supporting step224formed outside an end of the hollow portion222, and the fixing portions226formed around the hollow portion222to receive and fix the second flange216.

The hollow portion222is formed through the center of the rotating body220so that the supporting shaft210is inserted therein.

The supporting step224is disposed outside the end of the hollow portion222in the insertion direction of the supporting shaft210and supports the side, which faces the hollow portion222, of the second flange216.

The fixing portions226formed around the hollow portion222are ramified with a predetermined gap therebetween.

A fixing protrusion227bending toward the hollow portion222is formed at an end of each of the fixing portion226.

The fixing protrusions227form receiving grooves227afor fixing the second flange216therein by bending toward the hollow portion222. The fixing protrusions227may be formed on all the separate fixing portions226or may be alternately formed only some of the fixing portions226.

Further, the cut grooves227bmay be formed at sides of the fixing portions226with regular intervals for elastic transformation of the fixing protrusions227when the rotating body220and the supporting shaft210are combined.

In order to fit the second flange216of the supporting shaft210in the receiving grooves227aof the fixing protrusions227aof the rotating body220, an end221of the rotating body220and an end214bof the first flange214are spaced at a predetermined gap T1from each other so that the rotating body220can smoothly rotate without interference by the mounting structure202such as a containing body or a containing main body.

A reinforcing groove228recessed toward the hollow portion220is formed around the outer side of the rotating body222having this configuration.

The reinforcing groove228has a ring-shaped cross-section and a ring-shaped reinforcing member229is seated in the reinforcing groove228.

The reinforcing member229may be made of urethane that can prevent sliding and noise in a rotational motion.

A process of assembling the roller unit200having an integrated fastening portion according to the second embodiment of the present invention is described hereafter.

First, the supporting shaft210and the rotating body220, which are mounted on the mounting structure202such as a containing body or a containing main body and can be combined in an integrated unit to reduce friction resistance by changing sliding friction into rolling friction while the containing body is opened and closed, are prepared.

The supporting portion218protruding at a side of the second flange216of the supporting shaft210is placed parallel with the hollow portion222of the rotating body220to be inserted therein in order to combine the supporting shaft210and the rotating body222by forcible fitting.

As described above, with the supporting portion218of the supporting shaft210and the hollow portion222of the rotating body220arranged in parallel with each other, by inserting the supporting shaft210into the rotating body220, the supporting portion218of the supporting shaft210can be fitted in the hollow portion222of the rotating body220by a pushing device etc.

In this process, the second flange216of the supporting shaft210gradually moves to the hollow portion222in contact with the fixing protrusions227and the fixing protrusions227are elastically transformed and opened outward by the cut grooves227b, whereby a space in which the second flange216is inserted can be ensured.

That is, the second flange216is fitted into the receiving grooves227athrough the space ensured by elastic transformation of the fixing protrusions227.

When the supporting portion218of the supporting shaft210is inserted in the hollow portion222of the rotating body220, the second flange216having a larger outer diameter than the first flange214is positioned in the receiving grooves227aformed by the fixing protrusions227.

When the second flange216of the supporting shaft210is inserted in the receiving grooves227aof the rotating body220, the fixing protrusions227athat have been elastically opened by movement interference by the second flange216are returned to the initial positions, thereby firmly fixing the second flange216.

By this process, the roller unit200having an integrated fastening portion according to the second embodiment of the present invention can be fastened to the mounting structure202to be used by inserting a fastening tool into the tool groove218aand then turning the supporting shaft210for thread-fastening.

The roller unit200having an integrated fastening portion according to the second embodiment of the present invention includes: the supporting shaft210having the first and second flanges214and216formed in multi steps with different outer diameters to be fastened to a containing body or a containing main body that can slide; and the rotating body220having the fixing portions216surrounding the second flange216of the supporting shaft210. Therefore, it is possible to more conveniently combine the supporting shaft210and the rotating body220and prevent separation of the supporting shaft210and the rotating body220, whereby it is possible to improve various functions.

Third Embodiment

A roller unit300having an integrated fastening portion according to a third embodiment of the present invention includes: a support shaft310having first and second flanges314and316fastened to a containing body or a containing main body (hereafter, referred to as a mounting structure); a roller320rotatably coupled to a side of the support shaft310; and a fixing body330coupled to a side of the roller320and retaining the supporting shaft310and the roller320by being coupled to coupling portions324by coupling protrusions334.

The mounting structure302, which means a containing body for keeping for use necessary articles or a containing main body for accommodating the containing body, can be applied to various products such as furniture or a refrigerator.

The supporting shaft310has the first and second flanges314and316that are stepped with different outer diameters, and is fastened to the mounting structure302such as furniture of a refrigerator.

The supporting shaft310has a fastening portion312, the first flange314formed at a side of the fastening portion312, a second flange316having a larger outer diameter than the first flange314, and a supporting portion318protruding at a side of the second flange316.

The fastening portion312extends a predetermined length and is fastened to the mounting structure302.

The fastening portion312can be fastened to the mounting structure302in a thread-fastening type by forming a thread312alongitudinally around the outer side of the fastening portion312, or may be fastened in various ways such as forcible fitting. A contact surface314athat is in close contact with the mounting structure302is formed at the side, which faces the mounting structure302, of the first flange314.

The contact surface314amay be formed in a shape corresponding to the mounting structure302that the contact surface314afaces.

For example, when the portion of the mounting structure302that the contact surface314afaces is flat, the contact surface314ais made flat, and when it is uneven, the contact surface314ais also made uneven for close contact, whereby it is possible to prevent the thread-fastened fastening portion312from loosening.

The second flange316is formed on one body with the first flange314, but may have a larger outer diameter than the first flange314.

The reason of making the outer diameter D2cof the second flange316larger than the outer diameter D1cof the first flange314is for coupling the supporting shaft310to the roller320through the fixing body coupled to the coupling portion324with a surface of the second flange316in contact with the supporting step323of the roller320.

The supporting portion318protrudes toward the roller320, at a side of the second flange316.

The outer diameter D3cof the supporting portion318is made a little smaller than the inner diameter D4cof a hollow portion322of the roller320so that the supporting portion318can be easily inserted into the hollow portion322.

The outer side of the supporting portion318has a shape corresponding to the shape of the hollow portion322of the roller320.

An end of the support portion318may be chamfered to be smoothly inserted into the hollow portion322of the roller320.

A tool groove318amay be formed at the end of the supporting portion318in various shapes such as “+”, “−”, and “★” corresponding to fastening tools so that the roller unit300can be easily and conveniently fastened to the mounting structure302by the fastening tools.

The roller320has the hollow portion322, the supporting step323formed outside the end of the hollow portion322, and the fixing portion324formed outside the hollow portion and fixing the fixing body330.

The hollow portion322is formed through the center of the roller320so that the supporting shaft310is inserted therein.

The supporting step323is disposed outside the end of the hollow portion322in the insertion direction of the supporting shaft310and supports the side, which faces the hollow portion322, of the second flange316.

The coupling portion324is formed outside the hollow portion322and prevents separation of the roller320and the supporting shaft310by being coupled to the fixing body330.

The coupling portion324has coupling holes324acircumferentially arranged and fixing protrusions324bprotruding inward in the coupling holes324a.