WO2007139364A1

WO2007139364A1 - Self closing device for a slide

Info

Publication number: WO2007139364A1
Application number: PCT/KR2007/002667
Authority: WO
Inventors: Yoon Sik Park
Original assignee: Yoon Sik Park
Priority date: 2006-06-01
Filing date: 2007-06-01
Publication date: 2007-12-06

Abstract

Disclosed is a self-closing device with an improved durability. The self-closing device includes a stationary member fixed to an end of a stationary rail of a slide, a movable member and a movable pin coupled to the stationary member in a reciprocally movable manner, a pair of springs each having one end coupled to the stationary member and the other end coupled to the movable member, and a movable pin guide fixed to a movable rail of the slide. By providing weak portions of the respective constituent elements of the self-closing device with an enhanced strength and durability, the durability of the overall self-closing device can be enhanced. For example, it is possible to prevent a breakage at a weak portion of the spring by improving the shape of the spring, resulting in an increase in the durability of the self-closing device. Also, by providing the stationary member with a slot for facilitating the coupling of the movable pin, the coupling of the respective constituent elements of the self-closing device can be accomplished more easily.

Description

SELF CLOSING DEVICE FOR A SLIDE

Technical Field

[1] The present invention relates to a self-closing device for a slide, and more particularly, to a self-closing device with an improved durability and a slide to which the self-closing device is attached. Background Art

[2] When slides are used to pull or push a drawer out of or into an article of furniture, it is very convenient to attach a self-closing device to the slides. The self-closing device allows the drawer to be automatically and completely pushed into the article of furniture even if a user does not completely push the drawer into the article of furniture.

[3] Such a convenient self-closing device was developed and disclosed in Korean

Patent Application No. 2005-0047588 filed by the applicant of the present invention.

[4] FIG. 1 illustrates the disclosed self-closing device. The conventional self-closing device 20 is attached to a slide 10 at a predetermined position. Here, the shown slide 10 includes a stationary rail (outer member) 800, an intermediate movable rail (intermediate member) 900 to slide in the stationary rail 800, an inner movable rail (inner member) 700 to slide in the intermediate movable rail 900, and ball retainers 950 located between the respective rails. Although the shown slide 10 has a triple- telescopic structure, the self-closing device 20 is also applicable to a double-telescopic slide including a stationary rail and a movable rail. To install the slide 10, the stationary rail 800 is attached to an appropriate position of an article of furniture, for example, an inner sidewall of a desk, and the inner movable rail 700 is attached to an outer sidewall of a drawer 960. With this installation, a movement of the drawer 960 causes a sliding movement of the inner movable rail 700 and/or the intermediate movable rail 900.

[5] The self-closing device 20 for use with the slide 10 is installed near a rear end of the stationary rail 800, and a rear end of the intermediate movable rail 900 has an opening 910 to receive a part of the self-closing device 20 in a longitudinal direction thereof. The inner movable rail 700 has a coupling protrusion 710 protruding toward the intermediate movable rail 900.

[6] FIG. 2 is a perspective view of the self-closing device 20. The self-closing device

20 includes a movable pin 400, a movable member 200, a stationary member 100, and a pair of springs 500.

[7] Each of the springs 500 includes a body portion 510, a pair of head portions 530 formed at both ends of the body portion 510, and connecting portions 520 between the body portion 510 and the respective head portions 530, the connecting portions 520 having a smaller width than that of the body and head portions 510 and 530 (See FIG. 8 illustrating the spring and the end portion of the spring in detail). A side surface 533 of the head portion 530 and a side surface 523 of the connecting portion 520 are linearly parallel to a longitudinal direction of the spring 500. An end surface 531 of the head portion 530 is linearly perpendicular to the longitudinal direction of the spring 500.

[8] The movable pin 400 includes a guiding protrusion 410, a supporting pole 430, and a supporting plate 420 formed between the guiding protrusion 410 and the supporting pole 430 (See FIG. 3). Both the guiding protrusion 410 and the supporting pole 430 have a cylindrical shape.

[9] The stationary member 100, as shown in FIG. 5, has spring coupling portions 111 formed at opposite sides thereof, each spring coupling portion 111 being coupled with one end of the associated spring 500. The stationary member 100 also has a movable pin guide slot 123 longitudinally formed therein. The movable pin guide slot 123 includes a linear guide region 124 and a curved guide region 125. The spring coupling portions 111 have the same shape as that of spring coupling portions 212 formed at the movable member 200 (See FIG. 4). The spring coupling portions 212 will be described hereinafter in more detail. Further, the stationary member 100 has movable member sliding portions 121 formed at opposite sides thereof. The movable member sliding portions 121 have a thickness smaller than a thickness of the body of the stationary member 100. The thickness of the movable member sliding portions 121, however, is equal to a width of sliding grooves 222 of the movable member 200 that will be described hereinafter, so as to allow the movable member sliding portions 121 to be inserted into the sliding grooves 222, respectively.

[10] The movable member 200, as shown in FIG. 4, includes an approximately rectangular plate portion 210, sliding poles 220 integrally formed with the plate portion 210 at opposite sides of the plate portion 210, and the spring coupling portions 212 formed at opposite outer sides of the respective sliding poles 220.

[11] The plate portion 210 has a hole 211, into which the movable pin 400 is inserted to move left and right. The plate portion 210 also has a shock- absorbing portion 213 to attenuate a shock applied to the movable member 200 when the movable member 200 collides with a certain object. Each of the sliding poles 220 is formed with a protrusion 221 and the U-shaped sliding groove 222 to be coupled with the associated movable member sliding portion 121 of the stationary member 100.

[12] Each of the spring coupling portions 212 includes a first coupling surface 231 to be coupled with the side surface 533 of the spring head portion 530, a second coupling surface 233 to be coupled with the end surface 531 of the head portion 530, and a third coupling surface 237 to be coupled with the side surface 523 of the spring connecting portion 520. All the coupling surfaces 231, 233, and 237 are linear surfaces to correspond to the shape of the corresponding coupling spring. The spring coupling portion 212 also has an end surface 235.

[13] The self-closing device 20, as shown in FIGS. 6 and 7, further includes a movable pin guide 300 to be coupled to an inner bottom of the inner movable rail 700, the movable pin guide 300 being separably coupled with the movable pin 400.

[14] The movable pin guide 300 has a movable pin guiding groove 350, and the movable pin guiding groove 350 includes a movable pin entrance region 310 and a movable pin restraining region 320. The movable pin entrance region 310 is defined by a first entrance surface 311 and a second entrance surface 312, and the movable pin restraining region 320 is defined by a first linear restraining surface 323, a second linear restraining surface 324, and a curved restraining surface 325. The second linear restraining surface 324 of the movable pin restraining region 320 is formed with a restraining recess 328 for restraining the movable pin 400 therein. The movable pin guide 300 also has a slot 330 into which the coupling protrusion 710 (See FIG. 1) of the inner movable rail 700 is inserted, and shock-absorbing poles 340 formed at opposite side surfaces thereof. The shock-absorbing poles 340 are able to be slightly bent outward, and a shock- absorbing groove 341 is formed around each shock- absorbing pole 340. Since the shock-absorbing poles 340 can be bent outward, referring to FIG. 7 illustrating a rear surface of the movable pin guide 300 (here, the rear surface is a surface to be coupled with the inner movable rail), the shock- absorbing poles 340 are protruded outward as compared to opposite side surfaces of the movable pin guide 300.

[15] After the guiding protrusion 410 of the movable pin 400 is inserted into the movable pin guide slot 123 to couple the movable pin 400 with the stationary member 100, the sliding grooves 222 of the movable member 200 are inserted onto the movable member sliding portions 121 of the stationary member 100, and simultaneously, the guiding protrusion 410 of the movable pin 400 is inserted into the hole 211 of the movable member 200 to couple the movable member 200 with the stationary member 100. One end of each spring 500 is coupled with the associated spring coupling portion 111 of the stationary member 100, and the other end of the spring 500 is coupled with the associated spring coupling portion 212 of the movable member 200, to complete the self-closing device 20 as shown in FIG. 2. In such an assembled state of the self- closing device 20, the movable member 200 slides along the movable member sliding portions 121 of the stationary member 100, and simultaneously, the movable pin 400 is integrated with the movable member 200 to move along the movable pin guide slot 123 of the stationary member 100.

[16] Now, the operation of the self-closing device 200 will be described with reference to FIGS. 8 to 10. It is noted that the slide shown in FIGS. 8 to 10 consists of three members including two movable rails (the intermediate movable rail and the inner movable rail) and the single stationary rail, but the illustration of the intermediate movable rail between the inner movable rail 700 and the stationary rail 800 is omitted for a simplification in illustration, and also, only the slide is shown without the illustration of a drawer and a desk wall portion. Also, although the movable pin guide 300 is fixed to the inner bottom of the inner movable rail 700 so as to face the stationary member 100 fixed to the stationary rail 800 and therefore, is not viewed from the outside, for the convenience of description, the movable pin guide 300 is represented by a solid line in FIGS. 8 to 10.

[17] Referring to FIG. 8, the stationary member 100 is coupled to the stationary rail 800 of the slide by use of rivets 112 and 131, and the movable pin guide 300 coupled with the coupling protrusion 710 of the inner movable rail 700 of the slide is separated from the stationary member 100. Specifically, as a drawer is pushed from an opened position to a closed position thereof, the inner movable rail 700 of the slide is moved from a pull-out position toward a push-in position thereof, and the movable pin 400, which is inserted into the hole 211 of the movable member 200 to move together with the movable member 200, is caught by the curved guide region 125 of the movable pin guide slot 123 of the stationary member 100. The springs 500 are pulled to the maximum extent.

[18] Referring to FIG. 9, the inner movable rail 700 is further moved inward close to the push-in position, and the movable pin guide 300 is coupled with the movable pin 400 caught by the curved guide region 125. The movable pin 400 is first inserted into the movable pin entrance region 310 defined by the first and second entrance surfaces 311 and 312, and continuously, is moved along the first linear restraining surface 323 and the second linear restraining surface 324 of the movable pin restraining region 320. With this movement, the movable pin 400 is released from the curved guide region 125. As soon as the movable pin 400 is completely separated from the curved guide region 125, the movable member 200 is moved to a completely pushed position thereof as the movable pin 400, adapted to move together with the movable member 200, is moved along the linear guide region 124 of the stationary member 100 by a tensile force of the springs 500 until the movable member 200 is caught by a stepped restraining portion 119 of the stationary member 100. In this case, since the supporting pole 430 of the movable pin 400 is caught on the second linear restraining surface 324 of the movable pin guide 300, the movable pin guide 300 moves along the movable pin 400, thereby causing the inner movable rail 700 of the slide to automatically move to a completely pushed position thereof. The restraining recess 328, formed at the second linear restraining surface 324, is positioned to restrain the movable pin 400 at a time point when the movable pin 400 is almost separated from the curved guide region 125. Thereby, as soon as the movable pin 400 is separated from the curved guide region 125, the movable pin 400 is safely caught by the restraining recess 328 to move along the linear guide region 124.

[19] Referring to FIG. 10, the movable pin guide 300 is kept in a completely pushed position of the slide (i.e. a completely closed position of the drawer) by the force of the springs 500 while being coupled with the movable pin 400. The pulling-out of the slide is accomplished in reverse of the above described order.

[20] The above described known self-closing device has advantages of low manufacturing costs and convenient use. However, when any one of the above described constituent elements of the self-closing device is damaged as will be described hereinafter, the overall device is no longer useful, or the assembling of the constituent elements is difficult.

[21] The above described self-closing device is fabricated by injection molding a plastic material having an appropriate strength. When the drawer is moved to a completely pushed position thereof by the force of the springs 500, the movable pin 400 is moved to a completely pushed position thereof while being coupled with the movable pin guide 300. In this case, there is the risk that the supporting pole 430 of the movable pin 400 is broken or bent by a shock force (i.e. a force applied by the load of the movable rails of the slide and the load of the drawer and contents received in the drawer to the respective associated portions of the self-closing device until the self-closing device is moved to and stopped at a completely pushed position thereof by the force of the springs) and/or by repetitive coupling and separation with the movable pin guide 300. This may result in malfunction of the movable pin 400.

[22] When the movable pin 400 is inserted into the movable pin guide slot 123 of the stationary member 100, the movable pin 400 has to be tilted such that the guiding protrusion 410 of the movable pin 400 forcibly pushes a supporting piece 127 of the stationary member 100 toward a shock-absorbing space 126 (See FIG. 5). In this case, it is difficult to push the movable pin 400 into the shock-absorbing space 126 because of a resistance of the supporting piece 127. That is, inserting the movable pin 400 into the stationary member 100 is very troublesome.

[23] Meanwhile, in the course of pushing the inner movable rail 700, having the movable pin guide 300 attached thereto as described above, into the drawer (from the state shown in FIG. 8 to the state shown in FIG. 9), a tip end of the inner movable rail 700 is caught by the plate portion 210 of the movable member 200 rather than passing over the movable member 200 before the movable pin guide 300 is coupled with the movable pin 400. Therefore, in the case of the conventional slide, as shown in FIG. 11, the tip end of the inner movable rail 700 has a cut portion 750 to allow the tip end of the inner movable rail 700 to pass over the movable member 200 for enabling the coupling of the movable pin guide 300 and the movable pin 400. However, with the provision of the cut portion 750 at the tip end of the inner movable rail 700, only a part of a contact surface 750 to come into contact with retainer balls remains at the tip end of the inner movable rail 700, thus making it impossible to achieve smooth rolling motions of the ball retainers 950. This causes the cut portion 750 from interfering with the ball retainers 950 in the course of pulling out the slide. Accordingly, there is the problem in that smooth sliding movements of the slide may be hindered as the inner movable rail 700 accesses to a maximum pull-out position thereof. Disclosure of Invention Technical Problem

[24] It is a first object of the present invention to provide a self-closing device having a movable pin with an improved durability.

[25] It is a second object of the present invention to provide a self-closing device in which a movable pin can be easily coupled to a stationary member.

[26] It is a third object of the present invention to provide a self-closing device attached to a slide, which causes no interference between an inner movable rail and ball retainers of the slide.

[27] It is a fourth object of the present invention to provide a self-closing device having a movable pin guide with an improved durability.

[28] It is a fifth object of the present invention to greatly improve the durability of a self- closing device by greatly improving the durability of springs used in the self-closing device.

[29] It is a sixth object of the present invention to provide a slide to which a self-closing device with an improved durability is attached. Technical Solution

[30] In accordance with the present invention, the above and other objects can be accomplished by the provision of a self-closing device with an improved durability, comprising: a pair of springs; a stationary member having a pair of spring coupling p ortions and a pair of movable member sliding portions formed at opposite sides thereof, each spring coupling portion being coupled with one end of the associated spring, the stationary member also having a movable pin guide slot perforated therein and including a linear guide region and a curved guide region; a movable member having a plate portion centrally formed with a hole, sliding grooves formed at opposite sides of the plate portion to be coupled with the respective movable member sliding portions, and spring coupling portions formed at opposite outer sides of the sliding grooves, each spring coupling portion being coupled with the other end of the associated spring, the movable member reciprocally moving along the movable member sliding portions of the stationary member; a movable pin having a supporting pole to be inserted into the hole of the movable member, the movable pin moving along the movable pin guide slot of the stationary member while being integrated with the movable member; and a movable pin guide having a movable pin guiding groove to be detachably coupled with the movable pin.

[31] In the above self-closing device, the movable pin guide moves along an inner movable rail of a slide, and the stationary member is fixed to one end of a stationary rail of the slide to correspond to the movable pin guide. Thereby, when the movable pin guide is coupled with the movable pin as a drawer is pushed into an article of furniture, the movable pin guide is moved inward by a constrictive force of the springs. Thereby, the self-closing device allows the drawer to be automatically pushed to the maximum extent even when a user does not completely push the drawer into the article of furniture.

[32] According to the present invention, the stationary member further has a coupling hole formed at an end of the linear guide region of the movable pin guide slot, to facilitate the coupling of the movable pin.

[33] The movable pin further has a reinforcing portion formed at a lower end of the supporting pole, and the stationary member further has a receiving recess formed along a periphery of the movable pin guide slot, to receive a supporting plate of the movable pin. With this configuration, the durability of the movable pin is improved, resulting in an increase in the durability of the overall self-closing device.

[34] The stationary member further has a reinforcing plate portion formed at an end thereof where the spring coupling portions are located. The reinforcing plate portion absorbs a shock force generated when the slide is automatically pushed, thereby further increasing the durability of the self-closing device.

[35] Each of the reinforcing plate portion of the stationary member and the plate portion of the movable member has rail passages formed at opposite sides thereof to facilitate the sliding of the inner movable rail. This eliminates a need for providing the inner movable rail of the slide with a cut portion, and consequently, stabilizes the pulling-out operation of the inner movable rail by eliminating the risk of interference as represented by the prior art.

[36] According to the present invention, the movable pin guide has a box-shaped body formed with the movable pin guiding groove to be detachably coupled with the movable pin and also formed with a coupling slot to be coupled with a coupling protrusion of the movable rail. The movable pin guiding groove includes a movable pin entrance region defined by a first entrance surface and a second entrance surface and a movable pin restraining region defined by a first restraining surface, a second restraining surface, and a third restraining surface. The respective surfaces of the movable pin entrance region and the movable pin restraining region are curved surfaces, and the first and second entrance surfaces are smoothly connected with the first and second restraining surfaces, respectively. This configuration has the effect of attenuating noise generated in use of the movable pin guide.

[37] The body of the movable pin guide is provided, at a side thereof, with a reinforcing plate to cover the guiding groove. The reinforcing plate increases the durability of the movable pin guide.

[38] Preferably, the movable pin guide has a resilient coupling structure provided at sidewalls of the body thereof, and the resilient coupling structure includes supporting walls integrally formed with the sidewalls of the body and resilient couplers extending from the respective supporting walls to be coupled with the sidewalls of the movable rail of the slide. With this configuration, the movable pin guide can be easily attached to the sidewalls of the movable rail of the slide.

[39] Preferably, the reinforcing plate of the movable pin guide is formed thereon with a supporting block to be inserted into a hole of the movable rail.

[40] According to the present invention, each spring includes a body portion, head portions formed at both ends of the body portion, and connecting portions located between the body portion and the head portions and having a width smaller than that of the body and head portions. A side surface of the head portion is inclined relative to a longitudinal axis of the spring. Each spring coupling portion of the stationary member and the movable member has a cross sectional shape corresponding to that of the head portion and the connecting portion of the spring seated in the spring coupling portion.

[41] The side surface of the head portion is linearly or arcuately inclined relative to the longitudinal axis of the spring. When the side surface is linearly inclined, an inclination angle of the side surface of the head portion is preferably in a range of 5 to 85 degrees.

[42] In accordance with another aspect of the present invention, there is provided a slide to which the above described self-closing device is attached. Brief Description of the Drawings

[43] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[44] FIG. 1 is a perspective view of a slide, to which a conventional self-closing device is attached; [45] FIG. 2 is a perspective view of the conventional self-closing device shown in FIG.

1; [46] FIG. 3 is a perspective view of a movable pin used in the self-closing device shown in FIG. 2; [47] FIG. 4 is a perspective view of a movable member used in the self-closing device shown in FIG. 2; [48] FIG. 5 is a plan view of a stationary member used in the self-closing device shown in FIG. 2; [49] FIG. 6 is a perspective view of a movable pin guide used in the self-closing device shown in FIG. 2;

[50] FIG. 7 is a rear view of the movable pin guide shown in FIG. 6;

[51] FIGS. 8 to 10 are views illustrating the operation of the self-closing device shown in FIG. 2; [52] FIG. 11 is a perspective view of an inner movable rail included in the slide shown in FIG. 1;

[53] FIGS. 12 and 13 are a front perspective view and a rear perspective view of a self- closing device according to the present invention; [54] FIG. 14 is a perspective view of a movable pin used in the self-closing device according to the present invention; [55] FIG. 15 is a perspective view of a stationary member used in the self-closing device according to the present invention; [56] FIG. 16 is a perspective view of a movable member used in the self-closing device according to the present invention; [57] FIGS. 17 and 18 are a front perspective view and a rear perspective view of a movable pin guide used in the self-closing device according to the present invention; [58] FIG. 19 is a perspective view illustrating a state in which the movable pin guide according to the present invention is coupled to the inner movable rail of the slide; [59] FIG. 20 is a sectional view taken along the line A-A of FIG. 19;

[60] FIGS. 21 and 22 are plan views illustrating different embodiments of a spring having an improved durability according to the present invention; [61] FIG. 23 is a partial plan view illustrating the spring shown in FIG. 21, which is attached to a spring coupling portion of the movable member; and [62] FIG. 24 is a plan view of the spring used in the self-closing device shown in FIG.

12.

Best Mode for Carrying Out the Invention [63] Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. [64] As shown in FIGS. 12 and 13, a self-closing device 20' according to the present invention includes a movable pin guide 300', a stationary member 100', a movable member 200', a movable pin 400', and springs 500', which have the same basic configurations and operational effects as those of the previously described prior art. Accordingly, the following description deals with only improved configurations as compared to the prior art, and wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

[65] Referring to FIG. 14, the movable pin 400' according to the present invention, similar to the previously described conventional movable pin 400, includes the guiding protrusion 410, the supporting pole 430, and the supporting plate 420 between the guiding protrusion 410 and the supporting pole 430. A difference between the movable pin 400' and the conventional movable pin 400 is that a reinforcing portion 440 is formed around an end of the supporting pole 430 in contact with the supporting plate 420. While the supporting pole 430, inserted into the hole 211 of the movable member 200', reciprocally moves along the movable pin guide slot 123 of the stationary member 100' together with the movable member 200', the reinforcing portion 440 serves to prevent the lower end of the supporting pole 430 from being deformed by a shock force.

[66] Referring to FIG. 16, the movable member 200' has the same configuration as that of the conventional movable member 200 except for that the movable member 200' has no shock- absorbing portion 213 and is altered in the shape of the spring coupling portion 212' and also, is additionally formed with rail passages 218. Differently from the conventional spring coupling portion 212, the spring coupling portion 212' has no second coupling surface 233 to be coupled with the end surface 531 of the spring head portion 530. Rather, the spring coupling portion 212' has an inclined surface 239 located between the first coupling surface 231 and the third coupling surface 237. The function of the rail passages 218 will be described hereinafter.

[67] The stationary member 100', similar to the conventional stationary member 100, is formed, at opposite sides thereof, with the spring coupling portions 111 to be coupled with a pair of springs and the movable member sliding portions 121, and is also perforated therein with the movable pin guide slot 123 including the linear guide region 124 and the curved guide region 125.

[68] Differently from the conventional stationary member 100, as shown in FIG. 15, the stationary member 100' has a coupling hole 140 formed at an end of the linear guide region 124 of the movable pin guide slot 123 for facilitating the coupling of the movable pin 400'. The coupling hole 140 is positioned, to communicate with the linear guide region 124, at the end of the linear guide region 124 toward the spring coupling portions 111', more particularly, at a position closer to the spring coupling portions 111' than a maximum push-in position of the movable pin 400'. The coupling hole 140 has a diameter slightly larger than a diameter of the guiding protrusion 410 of the movable pin 400', to assure easy vertical insertion of the guiding protrusion 410. Alternatively, the coupling hole 140 may have a diameter slightly smaller than the diameter of the guiding protrusion 410 of the movable pin 400'. In this alternative configuration, the movable pin 400' has to be slightly tilted in order to be easily inserted into the coupling hole 140. Since the coupling hole 140 is positioned closer to the spring coupling portions 111' than the maximum push-in position of the movable pin 400', there is no risk that the movable pin 400' is separated from the coupling hole 140 during operation of the self-closing device 20'.

[69] Meanwhile, the stationary member 100' has a receiving recess 145 formed along a periphery of the movable pin guide slot 123, the receiving recess 145 having a greater depth than a height of the reinforcing portion 440 (See FIG. 15). Accordingly, the supporting plate 420 of the movable pin 400' is located in the receiving recess 145 so as to be lowered beyond the height of the reinforcing portion 440. Thereby, there is no risk that the reinforcing portion 440 comes into contact with an inner surface of the movable member 200' to thereby prevent smooth reciprocal movements of the movable pin 400'.

[70] The stationary member 100' also has a reinforcing plate portion 150 formed at an end thereof where the spring coupling portions 111' are formed (See FIG. 15). Preferably, the reinforcing plate portion 150, as shown in FIG. 12, is flushed with the plate portion 210 when the movable member 200' is coupled with the stationary member 100'. The reinforcing plate portion 150 allows the stationary member 100' to absorb a shock force applied during an operation of the self-closing device 20' to the some extent, thereby increasing the durability of the self-closing device 20'.

[71] Each of the reinforcing plate portion 150 of the stationary member 100' and the plate portion 210 of the movable member 200' according to the present invention is formed, at opposite sides thereof, with rail passages 152 or 218 (See FIG. 12). The rail passages 152 and 258 have a depth slightly larger than a height of the cut portion 750 of the previously described inner movable rail 700. Accordingly, when in use of the self-closing device 20' according to the present invention, the self-closing device 20' can achieve an efficient operation even if no cut portion 750 is provided at the inner movable rail 700, and consequently, the slide having the self-closing device 20' can be smoothly pulled out toward the maximum pull-out position thereof

[72] The coupling of respective elements of the self-closing device 20' will now be described.

[73] First, the guiding protrusion 410 of the movable pin 400' is vertically or obliquely inserted into the coupling hole 140 of the stationary member 100' such that an outer periphery of the supporting plate 420 meets an inner periphery of the coupling hole 140. Since the supporting plate 420 has a larger diameter than that of the coupling hole 140, there is no risk that the movable pin 400' is separated from the coupling hole 140 by passing through the coupling hole 140. Next, the movable pin 400' is moved slightly toward the curved guide region 125 such that the supporting plate 420 is coupled in the receiving recess 145 in a state wherein an inner sidewall of the stationary member 100' defining the movable pin guide slot 123 is engaged in a space between the guiding protrusion 410 and the supporting plate 420 of the movable pin 400'. Since a diameter of the guiding protrusion 410 is much larger than a width of the movable pin guide slot 123, the movable pin 400' can reciprocally move along the movable pin guide slot 123 without the risk of separation from the movable pin guide slot 123. Subsequently, similar to the prior art, the sliding grooves 222 of the movable member 200' are inserted onto the sliding portions 121 of the stationary member 100', and simultaneously, the guiding protrusion 410 of the movable pin 400' is inserted into the hole 211 of the movable member 20' to couple the movable member 200' with the stationary member 100'. Also, if the respective ends of the spring are coupled to the spring coupling portions of the stationary member 100' and the movable member 200', the self-closing device 20' as shown in FIGS. 12 and 13 can be completed.

[74] FIGS. 17 and 18 are a front perspective view and a rear perspective view, respectively, of the movable pin guide 300' according to the present invention.

[75] The movable pin guide 300', similar to the known movable pin guide 300, has a box-shaped body, which is formed with a movable pin guiding groove 350' to allow the movable pin 400 to be detachably coupled thereto, and the slot 330 to be coupled with the coupling protrusion 710 of the movable rail 700. The movable pin guide 300' according to the present invention is an improvement of the conventional movable pin guide 300, and the same reference numerals refer to the same elements.

[76] The movable pin guiding groove 350' includes a movable pin entrance region and a movable pin restraining region. The movable pin entrance region is defined by a first entrance surface 311' and a second entrance surface 312', and the movable pin restraining region is defined by a first restraining surface 323', a second restraining surface 324', and a third restraining surface 325'. In this case, the respective surfaces 311', 312', 323', 324', and 325' of the movable pin entrance region and the movable pin restraining region are curved surfaces as shown in FIG. 17. Also, the first entrance surface 311 'is smoothly connected with the first restraining surface 323', and the second entrance surface 312' is smoothly connected with the second restraining surface 324'.

[77] When the respective surfaces of the movable pin guiding groove 350' are curved, and the first entrance surface 311' and the second entrance surface 312' are smoothly connected with the first restraining surface 323' and the second restraining surface 324', respectively, the movable pin 400' can move smoothly along the respective surfaces of the movable pin guiding groove 350'. Also, the movable pin 400' can be smoothly coupled into or separated from the movable pin guiding groove 350'. In the case of the conventional movable pin guide 300 having the linear and curved surfaces, noise is generated at joints of the linear and curved surfaces in the course that the movable pin 400 is moved from the linear surface to the curved surface or in reverse. However, in the improved movable pin guide 300', the movable pin 400' smoothly moves along the curved surfaces, resulting in a remarkable reduction in the generation of noise.

[78] The movable pin guide 300' has a reinforcing plate 380 forming a surface of the body thereof to be attached to the slide rail 700 (See FIG. 19). The reinforcing plate 380, as shown in FIG. 18, is integrally formed with the body of the movable pin guide 300' and is formed to completely cover a side of the movable pin guiding groove 350'.

[79] The reinforcing plate 380 serves to securely support the respective surfaces of the movable pin guiding groove 350', thereby preventing the movable pin guiding groove 350' from being expanded by the movable pin 400 as the movable pin 400 is repeatedly coupled into and separated from the movable pin guiding groove 350'. This results in a considerable improvement in the durability of the movable pin guide 300'.

[80] The movable pin guide 300' has a resilient coupling structure including supporting walls 370 and resilient couplers 375 formed at sidewalls of the movable rail 700. The supporting walls 370 are integrally formed with the sidewalls of the body of the movable pin guide 300', and the resilient couplers 375 are obliquely extended outward from the respective supporting walls 370 to form a space between the resilient couplers 375 and the sidewalls of the body. The movable pin guide 300' is made of a plastic material having an appropriate elasticity. The resilient couplers 375 have an appropriate elasticity to be elastically deformable into the space.

[81] The movable pin guide 300' according to the present invention may have a supporting block 360. The supporting block 360 is formed on the reinforcing plate 380 of the movable pin guide 300', and has a box shape. The position and the size of the supporting block 360 are determined to conform to a hole 720 (See FIG. 11) that is formed in the inner movable rail in the course of punching the coupling protrusion 710 of the inner movable rail 700 to be inserted into the slot 330 of the movable pin guide 300'.

[82] Hereinafter, the operation of the resilient coupling structure and the supporting block 360 will be described.

[83] FIG. 19 is a perspective view illustrating the movable pin guide 300' attached to the coupling protrusion 710 of the inner movable rail 700, and FIG. 20 is a sectional view taken along the line A-A of FIG. 19.

[84] As shown in FIG. 20, generally, the sidewalls of the inner movable rail 700 are curved inward. When the above described resilient coupling structure including the supporting walls 370 and the resilient couplers 375 is formed at the movable pin guide 300' according to the present invention, the resilient couplers 375 are inserted into a recessed portion formed in a lower end of the curved sidewalls of the inner movable rail 700. The resilient couplers 375 are elastically deformable in the space between the resilient couplers 375 and the sidewalls of the body by virtue of the elasticity thereof, thereby being easily inserted into the recessed portion by passing over the curved sidewalls of the inner movable rail 700. Once the resilient couplers 375 are inserted into the recessed portion formed in the lower end of the curved sidewalls, it is possible to prevent the movable pin guide 300' from being separated from the coupling protrusion 710 of the inner movable rail 700 by an elastic supporting force of the resilient couplers 375 against the sidewalls of the inner movable rail 700. This results in an enhancement attachment capability of the movable pin guide 300'.

[85] In the case of the conventional movable pin guide 300, the movable pin guide 300 is coupled to the inner movable rail 700 only by the coupling protrusion 710 of the inner movable rail 700. Since the coupling protrusion 710 may be bent by a shock force applied when the slide is stopped after being moved to its completely pushed position and by a repetitive use thereof, there is the risk that the movable pin guide 300 deviates from a proper position thereof and fails to be engaged with the movable pin 400. This hinders a normal operation of the self-closing device.

[86] However, when the supporting block 360 is inserted into the hole 720 of the inner movable rail 700 according to the present invention, the supporting block 360 serves to support the movable pin guide 300', thereby eliminating the risk of bending of the coupling protrusion 710 even if a shock force is applied to the coupling protrusion 710.

[87] In the case of the known self-closing device, once the spring 500 is coupled to the spring coupling portion 212 (See the partial enlarged view of FIG. 8), the coupling portion 212 supports the spring 500 for allowing the extension and constriction of the spring 500. A supporting force of the coupling portion 212 is concentrated on the head portion 530 of the spring 500. In the case of the spring 500 having the above described conventional configuration and the coupling portion 212 having a shape corresponding to that of the spring 500, most of the supporting force is transmitted to the head portion 530 via a single spring line coming into contact with the second coupling surface 233 (See FIG. 4) of the spring head portion 530.

[88] In use of the self-closing device, there often occurs a breakage at a joint between the head portion 530 and the connecting portion 520 of the spring 500. Such a breakage may be a fatigue breakage caused as the supporting force is concentrated on the single spring line coming into contact with the second coupling surface 233 of the head portion 530. Accordingly, the applicant of the present invention proposes to improve the configuration of the second coupling surface 233 of the head portion 530.

[89] FIGS. 21 and 22 are plan views illustrating different embodiments of a spring having an improved durability according to the present invention.

[90] Each of springs 500-1 and 500-2 includes a body portion 510 and a connecting portion 520 similar to the prior art. A difference with the prior art is that a side surface 535 of the head portion 530 of the spring 500-1 is linearly inclined to have a predetermined inclination angle E relative to a longitudinal axis of the spring, and a side surface 537 of the head portion 530 of the spring 500-2 is arcuately inclined relative to the longitudinal axis of the spring. When the side surface 535 of the head portion 530 is linearly inclined relative to the longitudinal axis of the spring, the inclination angle E is preferably in a range of 5 to 85 degrees, and more preferably, in a range of 30 to 65 degrees. In the shown embodiment, the inclination angle is approximately 30 degrees.

[91] When the side surfaces 535 and 537 of the head portions 530 of the springs 500-1 and 500-2 are inclined relative to the longitudinal axis of the spring, the spring coupling portions 111' and 212' of the stationary member 100' and the movable member 200' have to be configured to correspond to the inclined side surfaces 535 and 537. With this corresponding configuration, the head portions of the springs can come into close contact with the spring coupling portions.

[92] FIG. 23 is a partial enlarged plan view of FIG. 21, and illustrates the head portion

530 of the spring 500-1 shown in FIG. 21 after being coupled with the spring coupling portion 212' of the movable member 200' having the configuration corresponding to that of the head portion 530.

[93] When the side surface of the spring head portion is inclined relative to the longitudinal axis of the spring and the spring coupling portions 111' and 212' have a cross sectional shape corresponding to that of the spring head portion, a supporting force applied to the spring head portion by the spring coupling portion can be dispersed via a plurality of spring lines rather than being concentrated on the single spring line. Accordingly, a breakage at the end portion of the spring can be prevented. With an experiment performed by the applicant of the present invention for testing the durability of the self-closing device by applying a constant load, it was found that the spring having the above described configuration according to the present invention can achieve an increase in durability as high as approximately four times that of the prior art.

[94] FIG. 24 is a plan view of the spring used in the self-closing device shown in FIG.

12, and illustrates an alternative embodiment of the spring shown in FIGS. 21 and 22.

[95] In the spring shown in FIG. 24, similar to the spring shown in FIG. 22, the side surface 537 of the head portion are arcuately inclined relative to the longitudinal axis of the spring and a beginning portion 515 of the body 510 extending from the connecting portion 520 is also arcuately inclined by a gentle inclination angle. By gently connecting the beginning portion 515 of the body 510 to the side surface 537 of the head portion so as to define a symmetrical shape, no stress concentrating portion occurs in the spring, resulting in an increase in the durability of the spring.

[96] When the self-closing device according to the present invention is applied to the slide, the stationary member 100' is fixed to an inner end of the stationary rail by use of appropriate fixing members such as rivets (See FIG. 8), and the movable pin guide 300' is fixed to the outer movable rail as shown in FIG. 15. The self-closing device, as shown in FIG. 1, is applicable to a double telescopic slide having a stationary rail and a movable rail as well as the triple telescopic slide as shown in FIG. 1.

[97] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and sprit of the invention as disclosed in the accompanying claims. For example, although the movable member 200' according to the embodiment of the present invention has no shock- absorbing portion 213 formed at the conventional movable member 200, the shock- absorbing portion 213 may be formed at the movable member 200' if necessary. Also, instead of fabricating the movable pin guide as a separate member to be attached to the outer movable rail, the movable pin guide 300' may be configured by, for example, punching the movable pin guiding groove 350' in the body of the intermediate movable rail (or the outer movable rail) at a position suitable to be coupled with the movable pin 400'.

Claims

[1] A self-closing device with an improved durability, comprising: a pair of springs; a stationary member having a pair of spring coupling portions and a pair of movable member sliding portions formed at opposite sides thereof, each spring coupling portion being coupled with one end of the associated spring, the stationary member also having a movable pin guide slot perforated therein and including a linear guide region and a curved guide region; a movable member having a plate portion centrally formed with a hole, sliding grooves formed at opposite sides of the plate portion to be coupled with the respective movable member sliding portions, and spring coupling portions formed at opposite outer sides of the sliding grooves, each spring coupling portion being coupled with the other end of the associated spring, the movable member reciprocally moving along the movable member sliding portions of the stationary member; a movable pin having a supporting pole to be inserted into the hole of the movable member, the movable pin moving along the movable pin guide slot of the stationary member while being integrated with the movable member; and a movable pin guide having a movable pin guiding groove to be detachably coupled with the movable pin, the movable pin guide moving along an inner movable rail of a slide, and the stationary member being fixed to one end of a stationary rail of the slide to correspond to the movable pin guide, whereby the self-closing device allowing a drawer to be automatically pushed to the maximum extent even if a user does not completely push the drawer into an article of furniture, wherein the stationary member further has a coupling hole formed at an end of the linear guide region of the movable pin guide slot, to facilitate the coupling of the movable pin.

[2] The self-closing device according to claim 1, wherein the movable pin further has a reinforcing portion formed at a lower end of the supporting pole.

[3] The self-closing device according to claim 1, wherein the stationary member further has a receiving recess formed along a periphery of the movable pin guide slot, to receive a supporting plate of the movable pin.

[4] The self-closing device according to claim 3, wherein the receiving recess has a depth larger than a height of the reinforcing portion of the movable pin.

[5] The self-closing device according to claim 1, wherein the stationary member further has a reinforcing plate portion formed at an end thereof where the spring coupling portions are located.

[6] The self-closing device according to claim 5, wherein each of the reinforcing plate portion of the stationary member and the plate portion of the movable member has rail passages formed at opposite sides thereof to facilitate the sliding of the inner movable rail.

[7] The self-closing device according to claim 1, wherein: the movable pin guide has a box- shaped body formed with the movable pin guiding groove to be detachably coupled with the movable pin and also formed with a coupling slot to be coupled with a coupling protrusion of the movable rail; the movable pin guiding groove includes a movable pin entrance region defined by a first entrance surface and a second entrance surface and a movable pin restraining region defined by a first restraining surface, a second restraining surface, and a third restraining surface; and the respective surfaces of the movable pin entrance region and the movable pin restraining region are curved surfaces, and the first and second entrance surfaces are smoothly connected with the first and second restraining surfaces, respectively.

[8] The self-closing device according to claim 7, wherein the body of the movable pin guide is provided, at a side thereof, with a reinforcing plate to cover the guiding groove.

[9] The self-closing device according to claim 7, wherein the movable pin guide has a resilient coupling structure provided at sidewalls of the body thereof, and the resilient coupling structure includes supporting walls integrally formed with the sidewalls of the body and resilient couplers extending from the respective supporting walls to be coupled with the sidewalls of the movable rail of the slide.

[10] The self-closing device according to claim 8, wherein the reinforcing plate of the movable pin guide is formed thereon with a supporting block to be inserted into a hole of the movable rail.

[11] The self-closing device according to claim 1, wherein: the movable pin guide is configured such that the movable pin guiding groove to be detachably coupled with the movable pin is formed near an end of the movable rail; the movable pin guiding groove includes a movable pin entrance region defined by a first entrance surface and a second entrance surface and a movable pin restraining region defined by a first restraining surface, a second restraining surface, and a third restraining surface; and the respective surfaces of the movable pin entrance region and the movable pin restraining region are curved surfaces, and the first and second entrance surfaces are smoothly connected with the first and second restraining surfaces, respectively .

[12] The self-closing device according to claim 1, wherein: each spring includes a body portion, head portions formed at both ends of the body portion, and connecting portions located between the body portion and the head portions and having a width smaller than that of the body and head portions; a side surface of the head portion is inclined relative to a longitudinal axis of the spring; and each spring coupling portion of the stationary member and the movable member has a cross sectional shape corresponding to that of the head portion and the connecting portion of the spring seated in the spring coupling portion.

[13] The self-closing device according to claim 12, wherein the side surface of the head portion is linearly inclined relative to the longitudinal axis of the spring.

[14] The self-closing device according to claim 13, wherein the inclination angle of the side surface of the head portion is in a range of 5 to 85 degrees.

[15] The self-closing device according to claim 12, wherein the side surface of the head portion is arcuately inclined relative to the longitudinal axis of the spring.

[16] A slide to which a self-closing device according to any one of claims 1 to 15 is attached.