TELESCOPLNG SELF-CLOSING MECHANISM BACKGROUND OF THE INVENTION FIELD OF INVENTION
This invention relates to a self-closing telescoping mechanism and, more particularly, to a self-closing telescoping mechanism where the mechanism moves automatically to a closed position when a predetermined minimum distance from closing has been reached. This invention further relates to a method of constructing a self-closing telescoping mechanism. DESCRIPTION OF THE PRIOR ART Self-closing telescoping mechanisms, for drawer slides and the like are known. Drawer slides are used in furniture and equipment including appliance equipment such as bottom mount refrigerators. The bottom mount refrigerators have a freezer located in the bottom portion of a refrigerator and the freezer section is accessible by opening and closing a drawer. The drawer has drawer slides on either side. The drawer opens in a normal manner, but when the drawer is moved from an open position toward a closed position, the drawer automatically closes after the drawer reaches a pre-determined distance from the fully closed position. If a freezer drawer is left open, serious problems can result. The freezer will operate continuously when the drawer is not fully closed and food items stored in the freezer can melt, resulting in damage to the food items. Damage can also be caused to the compressor of the freezer as it runs continuously and can overheat when the drawer is open. Previous self-closing mechanisms do not have a sufficiently long stroke, or, they fail prematurely and are no longer operable. For example, a self-closing mechanism might only operate if the drawer is within one inch of the fully closed position. In that event, a consumer can accidentally leave the drawer in an open position because the consumer does not close the drawer far enough to activate the self-closing
mechanism. Also, a self-closing mechanism might initially pull the drawer toward a fully closed position, but fail to fully close the drawer. Further, if the self-closing mechanism fails prematurely, the drawer can be accidentally left open because a consumer fails to close it completely and the mechanism does not assist the complete closing of the drawer. In addition, some self-closing mechanisms require too much force to set up the mechanism into the self-closing position or to activate the self-closing mechanism. Other self-closing mechanisms fail to re-set easily when they are activated prematurely. In either case, this increased difficulty can result in the drawer being left open. Previous self-closing mechanisms are located within a housing within a drawer slide, the housing limiting their stroke length and/or shortening the distance that the drawer can be opened. The housing is fixedly mounted in the drawer slide.
SUMMARY OF THE INVENTION A self-closing telescoping mechanism has an inner end and an outer end, the mechanism having at least two sections. The at least two sections are a first section and a second section. The mechanism has a floater that is slidably mounted in the first section near the inner end and is removably attached to the second section within a predeteraiined range near the inner end. The floater is biased toward the inner end by an elastic tether extending between the inner end and the floater. The floater is attached to the second section when the second section is within the predetermined range and detached from the second section when the second section is beyond the range.
A self-closing telescoping mechanism comprises at least two longitudinal sections that are sized and mounted to telescopingly slide relative to one another. The mechanism has an inner and an outer end, as well as a closed position and an open position. The at least two longitudinal sections comprise a first section
and a second section. The mechanism has a floater and the floater is slidably mounted in the first section near the inner end. The floater has an extended position and a retracted position and is connected to an elastic tether that biases the floater to the retracted position. Commencing with the floater in the retracted position and the mechanism in a closed position, the floater moves automatically to an extended position as the mechanism is opened. The movement of the floater is controlled by the movement of the second section. The floater has a maximum extended position wherein it is automatically fixed in a locked position in relation to the first section. The floater is automatically released from the locked position as the mechanism closes and the second section reaches a trigger point for the floater. When the floater is released, it is forced to the retracted position by the tether, thereby moving the mechanism to the closed position.
Preferably, the floater is not mounted in a housing. Still more preferably, the floater is slidably mounted directly in the first section or a covering in the first section.
A method of constructing a self-closing telescoping mechanism has at least two longitudinal sections that are sized and mounted to telescopingly slide relative to one another. The mechanism has an inner end and an outer end as well as a closed position and an open position. The at least two longitudinal sections comprise a first section and a second section. The mechanism has a floater, the floater being slidably mounted within the first section near the inner end. The method comprises constructing the floater to slide within the first section near the inner end in a predetermined range between the inner end and a maximum extended position wherein the floater is locked in position relative to the first section, tethering the floater to a retracted position at the inner end, shaping the second section and the floater so that the floater is attached to the second section within the predetermined range and detached from the second section beyond the
predetermined range, the floater attaching and detaching automatically and causing the floater to be locked into the first section in a maximum extended position.
BRIEF DESCRIPTION OF THE DRAWINGS Many of the intended advantages of the present invention would be more readily apparent and better understood if the following description is considered in connection with the accompanying drawings in which:
Figure 1 is a sectional view of two drawers, each mounted on three section self-closing drawer slides; Figure 2 is a perspective view of a three section drawer slide in a closed position;
Figure 3 is an enlarged partial perspective view of a drawer slide with a narrow section removed to expose a floater;
Figure 4 is a perspective view of a drawer slide in an open position; Figure 5 is an exploded perspective view of a floater;
Figure 6 is a view of a bottom of a floater;
Figure 5 is a partial perspective view of a floater locked in an extended position in a drawer slide;
Figure 8 is a partial perspective view of an outer surface of a drawer slide with the floater locked in the extended position;
Figure 9 is a partial perspective view of a drawer slide in a partially opened position;
Figure 10 is a partial perspective view of a self-closing drawer slide in a closed position with a narrow section partially cut away; Figure 11 is a partial perspective view of part of an underside of the narrow section;
Figure 12 is a top view of a further embodiment of a floater with a different latch plate; and
Figure 13 is a partial exploded perspective view of a floater and a covering; DESCRIPTION OF A PREFERRED EMBODIMENT
In Figure 1, there is shown a sectional side view of a cabinet 2 having two drawers 4. Each drawer 4 is supported by a pair of drawer slides 6 (only one of each pair being shown) comprised of three sections 8, 10, 12. The drawer slide 6 has a first section 8, a second section 12 and a third section 10. While the slides as shown in Figure 1 have three sections each and that is a typical number for a telescoping slide, slides can operate effectively with two or more sections. The slides preferably have ballbearings (not shown) located between adjacent sections to assist in the movement of the slides relative to one another. While ballbearings are preferred and are conventional, they are not necessary and slides can be designed to interface mutually without ballbearings. For example, slides can slide relative to one another by friction. The drawer slides 6 have a self-closing floater 14. When the drawer is in a closed position, as is the upper drawer 4 shown in Figure 1, the floater (not distinguishable in Figure 1) is at an inner end of each of the slides 6. When the drawer is open, as is the lower drawer 4 shown in Figure 1, the floater 14 slides toward an outer end of each of the slides 6.
In Figures 2 to 4, there is shown a perspective view of a drawer slide 6 having an outer channel 8, a middle channel 10 and narrow inner channel 12. The outer channel 8 corresponds to the first section and the narrow channel 12 corresponds to the second section. The middle channel 10 corresponds to the third section and allows the drawer to open by a greater distance than a two section slider would permit. In Figure 3, the inner channel 12 has been removed for ease of illustration to expose the entire floater 14. In Figure 2, the floater 14
and drawer slides 6 are in a closed position. In a closed position, the outer channel 8 and the inner channel 12 have inner ends 16, 18 respectively that are substantially adjacent to one another. The middle channel 10 is located approximately midway between the inner end 16 and an outer end 20 of the outer channel 8. An outer end 22 of the inner channel 12 is substantially adjacent to the outer end 20 of the outer channel 8 when the slide 6 is in a closed position. The floater 14 is mounted within the outer channel 8 and is sized and shaped to be slidable within the outer channel 8. A covering 23 is mounted within the outer channel 8 and the floater 14 is slidably mounted on the covering 23. The floater 14 is not mounted in a housing, but is mounted directly into the covering 23 of the outer channel 8 and is capable of sliding the entire length of the outer channel 8, if not otherwise prevented from doing so by the other channels 10, 12 or by a spring 34. The covering can be removed and the floater can be sized and shaped to be mounted directly in the outer channel 8. In the closed position of the slide 6, the floater 14 is in a retracted position as shown in Figures 2 and 3. In Figure 4, the floater 14 is shown in a maximum extended position in which the floater is in a locked position relative to the first section 8.
As best seen in Figure 3, the floater 14 has a lock 24 thereon, the lock being sized to fit within a slot 26 in the outer channel 8. The slot 26 is located approximately one-third of a distance toward the outer end 20 from the inner end 16 of the outer channel 8. The floater 14 also has a release 28 located thereon. The release 28 is slidable laterally to unlock the lock 24. The lock 24 is connected to pivot into or out of the slot 26. As the floater 14 slides towards the outer end 22 of the outer channel 8 and the lock 24 is directly above the slot 26, the downward force on the lock 24 will cause the lock to pivot into the slot 26. The floater 14 has a spring 34 connected between the floater 14 and the inner end 16 of the outer channel 8. At the inner end 16, the spring 34 is
connected to a bumper 35. When the floater 14 moves to an extended position and when the lock 24 inserted into the slot 26, the spring 34 exerts a force on the floater 14 toward the inner end 16. Preferably, there are ballbearings (not shown) between the middle channel 10 and the inner channel 12 and also between the middle channel 10 and the outer channel 8.
In Figure 5, there is shown an exploded view of the floater 14. The floater 14 has a body 38 with a size and shape to slidably fit within the covering 23 (not shown in Figure 5) of the outer channel 8. The lock 24 is pivotally mounted in an outer end 40 of the body 38 about a pivot point 42. The outer end 40 contains a cylindrical opening 43. A protrusion 44 on the lock 24 is sized to fit within the slot 26 (not shown in Figure 5). The spring 34 fits within a cylindrical passage 46 that extends along an imaginary longitudinal centre axis of the body 38. The lock 24 has an abutment 48 thereon. The abutment 48 corresponds to an arm 50 on the release 28. The release 28 is spring biased toward a left hand edge 52 (not shown in Figure 5, but see Figure 7) of the outer channel 8 (not shown in Figure 5), when viewed from the inner end 16 (not shown in Figure 5) of the outer channel 8. The release 28 has an elongated member 53 that abuts against a block 55. The release is said to be spring-biased because of the resiliency of the elongated member 53, which is preferably made of a plastic material. In Figure 3, there is shown an assembled perspective view of the body 38.
In Figure 6, there is shown an underside view of the assembled body 38 shown in Figure 3. The same reference numerals are used in Figure 6 as those used in Figure 5 to describe those components that are identical. It can be seen that the spring 34 has an outer end 54 that is affixed to the lock 24. In Figure 7, there is shown a partial top view of the floater 14 in an extended position within the outer channel 8. In Figure 8, there is shown an underside view of the floater 14 in an extended position within the outer channel
8. In Figures 7 and 8, the lock 24 is in a locked position with the protrusion 44 located in the slot 26. It can be seen that the release 28 has moved toward the left hand edge 52 and that the arm 50 is aligned with the abutment 48 to prevent the lock 24 from pivoting out of the slot 26. The release 28 and arm 50 maintain the floater 14 in a locked position with the protrusion 44 located in the slot 26. The same reference numerals are used in Figures 7 and 8 as those used in Figures 3 and 5 for those components that are identical.
In Figure 3, it can be seen that the arm 50 is located beside the abutment 48 when the floater is in the unlocked position. When the lock 24 pivots so that the protrusion 44 enters the slot 26 and locks the floater in the extended position in the outer channel 8, the spring bias moves the release 28 toward the left hand edge 52 so that the arm 50 is longitudinally aligned with the abutment 48. The arm 50 prevents the lock 24 from pivoting counterclockwise (when viewed from the side shown in Figure 2a) and thereby maintains the protrusion 44 within the slot 26. Thus, the floater 14 remains in a locked position relative to the outer channel 8. The same reference numerals are used in Figure 3 to describe those components that are identical to the components of Figures 1 and 2.
In Figure 9, the floater 14 remains in a locked position, but the inner channel 12 is moving toward a closed position. A lever 30 is pivotally mounted at a pivot point 32 to an interior surface (not shown in Figure 9) of the inner channel 12. In the closed position shown in Figures 2 and 3, the lever 30 is releasably coupled to the lock 24. Lever 30 exerts a force on the lock 24 in a direction towards the outer channel 8. In Figures 2 and 3, the force exerted by the lever 30 on the lock 24 would be considered to be a downward force (ie. toward the first section 8). At that instant, the lever 30 will become detached from the lock 24 and the inner channel 12 and middle channel 10 will be free to continue to move outward toward a fully open position. The inner channel 12 has a
partially cutaway portion so that it does not obscure the portions of the floater 14 that are located beneath the inner channel 12. The inner channel 12 has a V- shaped projection 56 extending inward from a sidewall thereof. As the inner channel 12 continues to move toward a closed position, it can be seen that the projection 56 will strike the release 28, thereby forcing the release further away from the left hand edge 52. The inner channel 12 provides a trigger point for releasing the floater from the locked position during the closing operation. This will move the arm 50 out of alignment with the abutment 48. By the time the projection 56 unlocks the lock 24 by triggering the release 28, the lever 30 will have moved to a position where the lever 30 is at least partially beyond the lock 24. The tension strength of the spring 34 will cause the lock 24 to pivot so that the protrusion 44 (not shown in Figure 9) exits the slot 26. The spring 34 will pull the floater 14 toward the inner end 16 of the outer channel 8 and the lever 30 will latch onto the lock 24 to move the inner channel 12 and the middle channel 10 to the closed position shown in Figure 1.
Figure 10 is a partial perspective enlarged view of the floater 14 in a retracted position and the slider 6 in a closed position. In other words, as the drawer is closed, the inner channel 12 releases the floater from the locked position and, almost simultaneously, the inner slide 12 becomes coupled again to the floater 14. The inner channel 12 is partially cut away to expose components that would otherwise be excluded by the channel. The force exerted by the spring 34 causes the floater to move automatically from the extended position to the retracted position and thereby self-closes the slider 6. An inner end of the spring 34 is affixed to the bumper 35, which is stationary and remains at the inner end 16 of the outer channel 8. The bumper 35 stops the floater at a fully retracted position. As shown in Figure 10, the narrow channel 12 has a raised portion 62 on an inner side surface thereof on a side away from the left hand edge 52. The
raised portion 62 serves as a backup to move the release 28 into a locked position as shown in Figure 9 as the drawer slide 6 is being opened. For example, if the spring mounting is not strong enough or fails to move the release to the locked position shown in Figure 9 from the unlocked position shown in Figure 10, the raised portion 62 will force the release to move toward the left hand edge 52 once the lock 24 has pivoted so that the protrusion 44 is located in the slot 26. Simultaneously, the lever 30 will become detached from the lock 24.
In Figure 11, there is shown a partial perspective view of an underside 64 of the inner end 18 of the inner channel 12. The V-shaped projection 56, the raised portion 62 and an underside 64 of the lever 30 are shown. The lever 30 has an extension 66 at a free end thereof. The extension 66 couples with the lock 24 (not shown in Figure 11) when the slide 6 (not shown in Figure 11) is in a closed position or when the slide 6 moves into an open position during the time when the floater moves from the retracted position to the extended position. As soon as the floater (not shown in Figure 11) becomes locked in the extended position, the lever 30 separates from the lock 24.
It is possible that the floater may be moved from a locked position to an unlocked position while the drawer of the two drawer slides supporting the drawer remains open. In other words, the protrusion 44 might accidentally be removed from the slot 26 before the drawer is moved toward the closing position and before the lever 30 re-couples with the lock 24. If the floater becomes unlocked prematurely, the self-closing mechanism will not operate while the drawer is being closed in that particular cycle. However, when the drawer has been fully closed, the lever 30, because it is preferably made of flexible material and, still more preferably, is made of plastic material, will override the lock 24 and become reset in the closed and retracted position of the drawer slide and floater respectively. Since the lever is pivoted about the pivot point 32, it can
move slightly sideways to move around the lock 24 and become coupled again or reset when the floater is in the initial position shown in Figure 3. The self-closing mechanism of the present invention resets without damage, and resets so smoothly that the resetting procedure is not apparent to a user. In Figure 12, there is shown a further embodiment of a release 68 for a floater 78, which is different from the release 28. The release 28 moves into the locked position because of the resiliency of the elongated member 53 which abuts against the block 55 (see Figures 9 and 10). By comparing Figure 3 with Figure 9, it can be seen that in the unlocked position of Figure 3, the elongated member 53 is generally parallel to the left hand edge 52. However, in the locked position of the release 28 shown in Figure 9, the elongated member 53 is at an angle relative to the left hand edge 52. The resiliency in the elongated member 53 has caused the release to move from the unlocked position of Figure 3 to the locked position of Figure 9 as soon as the release is free to do so. In Figure 12, a spring 74 moves a release 68 from an unlocked position to a locked position as soon as the protrusion 44 (not shown in Figure 12) on the lock 24 of the floater 78 becomes locked in the slot 26 (not shown in Figure 12). The spring 74 is mounted on a stub 76. The stub 76 is not connected to the release 68, which is free to move relative to the stub 74. The floater 78 is sized and shaped to slide directly in the outer channel 8 (not shown in Figure 12) with the covering removed. The same reference numerals are used in Figure 12 as those used in Figure 5 for those components that are identical.
In Figure 13, there is shown an exploded perspective view of the floater 14 and the covering 23. Preferably, the covering is made of plastic. The same reference numerals are used as those used in Figure 5 for those components that are identical.
The present invention can be used in various self-closing mechanisms and is not restricted to drawer slides. The self-closing mechanism is preferably used as a drawer slide. While the invention has been described in detail with respect to one drawer slide, there will obviously be two telescoping drawer slides on either side of each drawer with which the invention is to be used. Some drawers might be designed to have more than two drawer slides on each side. An advantage of the present invention over previous inventions is that the self-closing stroke lengths can be much longer than in previous devices and are not restricted by the length of the housing as the floater is not located in any housing. Further, in previous devices, the degree to which a drawer can be opened is limited or reduced by the size of the self-closing device. In other words, the longer the self- closing device, the smaller the distance that a particular drawer can be opened. With the present invention, the stroke length of the floater is determined by the length and strength of the spring and the location of the slot 26. The location of the slot 26 for a particular outer channel can be increased or decreased simply by changing the position of the slot 26 along the length of the outer channel and, if necessary, making corresponding changes to the spring. For example, an outer channel could have two slots 26 located longitudinally apart from one another. One of the two slots could be filled at all times with a removable plug. When it is desired to change the stroke length, the plug could be removed from one slot and placed into the other slot. If necessary, the spring could be replaced with a spring that is designed for the new stroke length. When used in a refrigerator or freezer, the spring is preferably zinc-coated for corrosion resistance. The spring can be coated with other corrosion resistant coatings as well or it can be made from corrosion resistance material (eg. stainless steel). In place of a spring, other elastic members or elastic tethers can be used. For example, an elongated neoprene tether could be used in place of the spring 34. It is important to have a
long stroke length for the self-closing mechanism as a consumer might still leave the drawer open if the stroke length is too short. The longer the stroke length, the more likely that a consumer will close the drawer by a sufficient distance to activate the self-closing mechanism. The self-closing mechanism of the present invention preferably has a stroke length of at least 2.5 inches and still more preferably as a stroke length of at least 3.0 inches.