Counterbalanced door system for a storage cabinet

Information

  • Patent Grant
  • 6779856
  • Patent Number
    6,779,856
  • Date Filed
    Thursday, February 21, 2002
    22 years ago
  • Date Issued
    Tuesday, August 24, 2004
    19 years ago
Abstract
A storage unit includes a cabinet defining an interior and a door assembly, which has a first door section and a second door section. Each of the door sections is pivotably mounted to the cabinet for movement between an open position and a closed position. The first and second door sections prevent access to the interior of the cabinet when in the closed position and provide access to the interior of the cabinet when in the oven position. The storage unit also includes a link pivotably interconnected between the first and second door sections so as to synchronize movement of the first and second door sections between the open and closed positions. A biasing arrangement counterbalances the door assembly and maintains the first and second door sections in both the open position and closed position and positions therebetween.
Description




BACKGROUND AND SUMMARY OF THE INVENTION




This invention relates to a storage unit, and more particularly to a counterbalancing arrangement for a door associated with an overhead-type storage unit.




An overhead storage unit typically includes a cabinet defining an interior and having an open front which provides access to the cabinet interior. A door is typically interconnected with the cabinet, and is movable between an open position in which the door allows access to the interior of the cabinet through the open front, and a closed position in which the door closes the open front of the cabinet to prevent access to the cabinet interior. Various types of doors are known, including flipper-type doors and doors which are mounted to the cabinet via an arm arrangement which provides pivoting movement of the door relative to the cabinet.




It is an object of the present invention to provide an overhead storage unit having a cabinet and a door arrangement in which a door is pivotably mounted to the cabinet for movement between open and closed positions, and which includes a counterbalancing arrangement that counterbalances the weight of the door to provide ease of movement of the door between its open and closed positions. It is a further object of the invention to provide an overhead storage unit having a counterbalanced clamshell-type door construction which includes a pair of door sections that are movable together and apart between their closed and open positions. It is a further object of the invention to provide an overhead storage unit having a clamshell-type door arrangement in which the door sections are synchronously moved between their open and closed positions, and in which the weight of the door components is counterbalanced so as to provide ease of movement of the door sections between their open and closed positions. Yet another object of the invention is to provide a counterbalanced door arrangement which can easily be incorporated into a cabinet without impinging on the interior storage space of the cabinet and which does not detract from the overall aesthetic external appearance of the storage unit. Yet another object of the invention is to provide an overhead storage unit with such a counterbalanced door arrangement which is relatively simple in its components and construction, and which can be easily incorporated into the assembly of the overhead storage unit.




In accordance with the invention, a storage unit, such as an overhead storage unit, includes a cabinet defining an interior and having an open front which provides access to the cabinet interior. The storage unit includes a door arrangement interconnected with the cabinet, which is movable relative to the cabinet between an open position in which the interior of the cabinet can be accessed through the open front of the cabinet, and a closed position in which the door arrangement closes the open front of the cabinet for preventing access to the cabinet interior. The door arrangement is counterbalanced so as to be biased toward its open position, to provide an assist to the user when the door arrangement is moved from its closed position to its open position, and for maintaining the door arrangement in its open position when so positioned by the user. In addition, the door arrangement is preferably of a clamshell-type construction, having a first door section and a second door section which are moved toward each other when the door arrangement is in its closed position, and moved apart from each other when the door arrangement is in its open position.




In one form, the first door section includes an upper door member extending between a pair of upper arms, each of which is pivotably mounted to the cabinet for providing movement of the upper door member between its open and closed positions. Similarly, the second door section may be in the form of a lower door member mounted between a pair of lower arms which are pivotably interconnected with the cabinet, for providing movement of the lower door member between its open and closed positions. Counterbalancing of the door arrangement is accomplished by interconnecting a biasing arrangement with one of the sets of arms, e.g. the upper arms, which tends to rotatably bias the arms upwardly so as to counterbalance the weight of the upper door member. In one form, the biasing arrangement is in the form of a spring connected between the cabinet and at least one of the upper arms. The spring and the upper arm are configured and arranged such that the spring applies a force to the upper arm which tends to rotate the upper arm about its pivot axis, to urge the upper arm upwardly. In another form, the biasing arrangement is in the form of a counterbalancing weight connected to the upper arm at a location rearwardly of its pivot axis, to bias the upper arm upwardly.




The upper and lower door sections are connected together so as to be synchronously movable between their open and closed positions. To accomplish this, a link member is interconnected between at least one of the sets of upper and lower arms. The link member is pivotably mounted to the upper arm at a location forwardly of the upper arm pivot axis, and is pivotably connected to the lower arm at a location rearwardly of the lower arm pivot axis. In this manner, the link member functions to raise the lower arm as the upper arm is lowered, to move the lower door section toward the upper door section and to bring the upper and lower door sections together when one of the door sections is moved toward its closed position. Likewise, the link member functions to lower the lower arm as the upper arm is raised, to move the upper and lower door sections apart when one of the door sections is moved toward its open position.




The weight of the components of the upper door section, located forwardly of the upper arm pivot axis, is operable to overcome the biasing force of the counterbalancing arrangement, to maintain the upper door section in position against the force of the biasing arrangement. In addition, the weight of the forward components of the upper door section is also sufficient to maintain the lower door section in position, by virtue of the link member which tends to raise the lower door section when the upper door section is closed. When the user moves either the upper door section or the lower door section away from its closed position toward its open position, the counterbalancing arrangement is operable to assist the user in opening the door sections, and the force of the counterbalancing arrangement maintains the door sections in any position when the user releases the door sections. When the door sections are in their open positions, the counterbalancing arrangement functions to maintain the door sections in the open position until the door sections are once again moved toward their closed positions against the force of the counterbalancing arrangement.




Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.











BRIEF DESCRIPTION OF THE DRAWINGS




The drawings illustrate the best mode presently contemplated of carrying out the invention.




In the drawings:





FIG. 1

is an isometric view of an overhead storage unit incorporating the counterbalanced door system of the present invention, showing the upper and lower door sections in an open position;





FIG. 2

is a section view taken along line


2





2


of

FIG. 1

, again showing the door sections in the open position;





FIG. 2A

is a view similar to

FIG. 2

, showing the door sections in the closed position;





FIG. 3

is a side elevation view of the upper door section forming a part of the door system incorporated into the overhead storage unit of

FIG. 1

;





FIG. 4

is a rear elevation view, with portions broken away, showing the upper door section of

FIG. 3

;





FIG. 5

is an isometric view of an upper arm incorporated into the upper door section of

FIG. 3

;





FIG. 6

is an elevation view of the upper arm of

FIG. 5

;





FIG. 7

is an isometric view of the lower door section, with portions broken away, forming a part of the door system incorporated into the overhead storage unit of

FIG. 1

;





FIG. 8

is an outer elevation view of one of the lower arms incorporated into the lower door section of

FIG. 7

;





FIG. 9

is an isometric view of the inner area of one of the lower arms of

FIG. 8

;





FIG. 10

is an inner elevation view of the lower arm of

FIG. 9

; and





FIG. 11

is a view similar to

FIG. 1

, showing an alternative embodiment for the biasing arrangement incorporated into the counterbalanced door system of the present invention.











DETAILED DESCRIPTION OF THE INVENTION




Referring to

FIGS. 1

,


2


and


2


A, an overhead storage unit


10


includes a cabinet assembly or case


12


formed of a bottom wall


14


, a top wall


16


, a pair of end walls


18


,


20


, and a back wall


21


, all of which cooperate to define an outwardly open interior in a manner as is known. A door assembly


22


, constructed in accordance with the present invention, is movably secured to case


12


for selectively providing and preventing access to the interior of case


12


.




Door assembly


22


includes an upper door section or subassembly


24


and a lower door section or subassembly


26


, which are interconnected with each other via a link


27


. Door assembly


22


is of a clamshell-type construction, such that upper door subassembly


24


and lower door subassembly


26


are selectively moved together and apart from each other between closed and open positions.

FIGS. 1 and 2

illustrate upper door subassembly


24


and lower door subassembly


26


in the open position, so as to provide access to the interior of case


12


.

FIG. 2A

illustrates upper door subassembly


24


and lower door subassembly


26


in the closed position, so as to prevent access to the interior of case


12


.




Upper door subassembly


24


includes a pair of upper arms


28


and an upper door member


30


connected between arms


28


. Similarly, lower door subassembly


26


includes a pair of lower arms


32


and a lower door member


34


extending between lower arms


32


.




As shown in

FIGS. 3-5

, each upper arm


28


includes an outer door mounting bracket section


36


and an inner arm section


38


, which are interconnected by an intermediate arm section


39


. A pivot stud


40


is mounted at the forward end of inner section


38


, extending inwardly therefrom. An opening


42


is formed at the end of inner section


38


, and an ear


44


extends upwardly from inner section


38


. The upper end of ear


44


terminates in a hook


46


.




The ends of upper door member


30


are mounted to and between outer door mounting bracket sections


36


of upper arms


28


. Representatively, fasteners such as screws


47


may extend through openings in outer door mounting bracket section


36


and into engagement with threaded anchors or openings associated with the underlying area of door


30


, to mount door


30


to and between arms


28


.




As shown in

FIGS. 1

,


2


and


2


A, each arm


28


is pivotably mounted to one of case end walls


18


,


20


via a pin


48


which extends through opening


42


, such that upper arms


28


are pivotable about a pivot axis defined by the aligned longitudinal axes of pins


48


. The upper end of each link


27


is pivotably mounted to a corresponding one of upper arms


28


through engagement of stud


40


within an opening


50


formed in the upper end of link


27


. A conventional retainer is engaged with stud


40


for retaining link


27


in position on stud


40


.




A spring


52


is engaged with each upper arm


28


. As shown in

FIGS. 1

,


2


and


2


A, the rear end of spring


52


includes a hook


53


which is fixed to case end wall


20


by engagement with a retainer pin


54


extending inwardly from case end wall


20


. The opposite, front end of spring


52


includes a hook


55


which is engaged with hook


46


at the upper end of ear


44


associated with inner arm section


38


. A similar spring


52


is engaged with upper arm


28


which is pivotably mounted to case end wall


18


. Springs


52


function to counterbalance the weight of upper door subassembly


24


, about the upper door section pivot axis defined by the upper arm pivot pins


48


. Referring to

FIG. 2

, springs


52


function to counterbalance upper door subassembly


24


in a counterclockwise direction about pivot pins


48


.




As shown in

FIGS. 7-10

, each lower arm


32


defines an outer door mounting section


58


, and lower door member


34


extends between door mounting sections


58


. Each lower arm


32


further includes an inner section


60


extending inwardly from the inner end of an intermediate section


62


which extends between each door mounting section


58


and inner section


60


. An inwardly extending pivot stud


64


is mounted toward the end of each inner section


60


, and an opening


66


is formed in each lower arm


32


at the intersection of intermediate section


62


and inner section


60


.




Referring to

FIG. 1

, a pivot pin


68


extends through each opening


66


so as to pivotably mount lower arms


32


to and between case end walls


18


,


20


for movement about a pivot axis defined by the aligned longitudinal axes of pins


68


. The lower end of each link


27


is pivotably mounted to one of lower arms


32


via engagement of stud


64


within an opening


70


formed in a link


27


. Again, a conventional retainer is engaged with stud


64


for retaining link


27


in position on stud


64


.




The shape of lower arm door mounting section


58


corresponds to the general shape of the cross section of lower door member


34


. In the illustrated embodiment, lower door member


34


is in the form of an extrusion member formed of any satisfactory material such as rigid thermoplastic or aluminum, defining a closed shape. Lower door member


34


includes an angled surface


72


which extends downwardly and forwardly relative to bottom wall


14


when lower door assembly


26


is in its open position as shown in

FIG. 1

, and which is located closely adjacent or in engagement with the lower end of upper door member


30


when lower door assembly


26


is in its closed position. Lower door member


34


further includes a recess


74


(

FIG. 2

) along its length, which provides a hand grip area for facilitating manual engagement with lower door member


34


.




Referring to

FIGS. 9 and 10

, door mounting section


58


of each lower arm


32


includes a series of ridges


76


which correspond to the shape of an internal passage defined by lower door member


34


. Ridges


76


facilitate engagement of each lower arm


26


with lower door member


34


, which are secured together in any satisfactory manner such as by means of a structural adhesive, welding or the like. Lower arms


32


may be formed of a rigid thermoplastic material such as polycarbonate in an injection molding process, although any other satisfactory material and forming method may be employed.




In operation, upper door subassembly


24


and lower door subassembly


26


function as follows to selectively provide and prevent access to the interior of case


12


.




With door assembly


22


in its open position as shown in

FIGS. 1 and 2

, springs


52


provide rearward biasing forces on upper arms


28


tending to pivot upper arms


28


in a counterclockwise direction about pivot pins


48


. The bias of springs


52


maintains counterbalances the weight of the components of door assembly


22


, due to the application of a downward and rearward force on each upper arm


28


at a location offset vertically above pivot pin


48


. The force of each spring


52


is selected so as to ensure that springs


52


are capable of maintaining both upper door subassembly


24


and lower door subassembly


26


in any desired position when released by the user. With upper door subassembly


24


in its open position, link


27


is positioned so as to place lower door subassembly


26


in its open position as shown in

FIGS. 1 and 2

. Link


27


includes a notch


77


which receives pivot pin


48


when door assembly


22


is in its open position.




When it is desired to close door assembly


22


, the user manually engages either upper door member


30


or lower door member


34


, typically by manually engaging recess


74


in lower door member


34


or the forward end of upper door member


30


. The user then exerts a downward force on upper door member


30


or an upward force on lower door member


34


. This causes upper arms


28


to pivot about pins


48


in a clockwise direction or lower arms


32


to pivot in a counterclockwise direction, with reference to

FIG. 2

, against the biasing force exerted by springs


52


.




As upper door subassembly


24


and lower door subassembly


26


are moved in this manner, link


27


is simultaneously moved in a downward direction through engagement with studs


40


,


64


. This downward movement of link


27


exerts a downward force on either the inner end


60


of lower arm


32


or on upper arm


28


at the location of stud


40


. As shown in

FIGS. 1 and 2

, when door assembly


22


is in its open position, stud


40


of upper arm


28


is located above and forwardly of pivot pin


48


, and stud


64


of lower arm


32


is located above and rearwardly of pivot pin


68


. When lower door member


34


is being lifted so as to close door assembly


22


, the downward force exerted by link


27


functions to pivot upper arm


28


about pivot pin


48


, to move upper door subassembly


24


toward its closed position against the force of spring


52


. The user continues such upward movement of lower door subassembly


26


and the resultant downward movement of upper door subassembly


24


until upper door member


30


and lower door member


34


are moved together in a closed position, as shown in FIG.


2


A. In a similar manner, application of a downward force on upper door member


30


causes clockwise pivoting movement of upper arm


28


about pivot pin


48


, which exerts a downward force on link


27


through engagement of link


27


with stud


40


. This downward force on link


27


is applied to lower arm


32


at stud


64


, which causes simultaneous counterclockwise pivoting movement of lower arm


32


about pivot pin


68


to move lower door member


34


upwardly. Downward movement of upper door member


30


continues until upper door member


30


and lower door member


34


are moved together to a closed position. A lock, shown generally at


78


, is mounted to upper door member


30


toward its lower end so as to engage a slot


80


formed in surface


72


of lower door member


34


, to lock door assembly


22


in its closed position.




The majority of the weight of upper door subassembly


24


is located outwardly of pivot pins


48


when upper door subassembly


24


is closed, and the moment at pivot pins


48


when upper door assembly


24


is closed is sufficient to overcome the biasing forces of springs


52


and lower door subassembly


26


, to maintain door assembly


22


in its closed position. When it is once again desired to open door assembly


22


, the user exerts an upward force on upper door assembly


24


, or a downward force on lower door subassembly


26


, and springs


52


counterbalance the weight of upper door subassembly


24


to easy movement of door assembly


22


toward its open position. When door assembly is in its open position, detents associated with cabinet end walls


18


,


20


and upper arms


28


provide a stop for maintaining door assembly


22


open, and a user-perceptible feel that the open position has been reached.




Movement of door assembly


22


from its closed position toward its open position causes a reduction in the moment at pivot pins


48


. The force of spring


52


is selected such that the force of spring


52


progressively decreases in proportion to reduction of the moment at pivot pins


48


, to enable the components of door assembly


22


to remain at any angular position when released by the user. When door assembly


22


is moved from its open position to its closed position, the user need only apply the force sufficient to overcome the counterbalancing force of spring


52


. This construction provides smooth and easy operation of door assembly


22


as it is moved between its open and closed positions.




It can also be appreciated that, when door assembly


22


is in its closed position, lower door subassembly


26


functions to apply a biasing force tending to urge door assembly


22


toward its open position. The majority of the weight of the components of lower door subassembly


26


is spaced forwardly of pivot pin


68


when door assembly


22


is closed, which applies a clockwise moment at pivot pin


68


tending to urge link


27


upwardly. This upward force on link


27


combines with the force applied by spring


52


to provide an upward bias on upper door subassembly


24


, which assists in counterbalancing upper door subassembly


24


by applying a counterclockwise biasing moment at pivot pin


48


.




The operating components of door assembly


22


located adjacent end walls


18


,


20


are typically located within a space defined between each end wall and an interior cover panel which prevents articles from coming into contact with the components of door assembly


22


.





FIG. 11

illustrates an alternative storage unit


10


′, which contains many of the same components as storage unit


10


, as indicated by like reference characters. In this version, upper arms


28


′ each define an inner end


82


extending rearwardly of pivot pin


48


. A counterweight


84


is secured to each inner end


82


, for providing a counterclockwise bias on upper arms


28


′ tending to move upper door member


30


toward its open position. Counterweights


84


function in the same manner as springs


52


to assist door assembly


22


′ of storage unit


10


′ to move to its open position and to retain the components of door assembly


22


′ in the open position. The weight of counterweight


74


is selected so that, when door assembly


22


′ is in its closed position in which upper door member


30


and lower door member


34


are moved together, the moment exerted by upper door subassembly


24


′ is sufficient to maintain door assembly


22


′ closed.




While the invention has been shown and described with respect to particular embodiments, it is understood that variations and alternatives are contemplated as being within the scope of the present invention. For example, and without limitation, the biasing force of either spring


52


or counterweight


84


has been shown as being applied to upper arms


28


. It is also understood that the biasing force may be applied to lower arms


32


or to link


27


. In addition, while a linear spring has been shown and described as one way to apply the biasing force, it is also contemplated that a torsion spring may be employed to provide a biasing force tending to rotate either upper door subassembly


24


or lower door subassembly


26


toward its closed position. While a single link has been illustrated as being connected between upper arm


28


and lower arm


32


, it is also contemplated that a linkage consisting of multiple links may be interposed between the upper and lower arms, or that a gear arrangement may be employed to synchronize movement of upper door subassembly


24


and lower door subassembly


26


. A spring or counterweight may be provided at either end of door assembly


22


or at only one of its ends, to provide the biasing force, if desired.




In addition, the counterbalancing feature of the present invention may be provided in a cabinet assembly having a single door member, and need not be employed in a clamshell-type door having two door members as shown and described. In a version such as this, link


27


and lower door subassembly


26


are omitted and upper door


30


is constructed so as to fully enclose the open front of case


12


when in its closed position.




Further, while upper arms


28


and lower arms


32


are shown as being pivotably mounted to cabinet assembly


12


at spaced apart locations, it is also contemplated that upper arms


28


and lower arms


32


may be pivotably mounted to cabinet assembly


12


for movement about a common pivot axis. While the door assembly has been shown and described with respect to pivotable mounting of the arms to the end walls of the cabinet assembly, it is also contemplated that the arms may be mounted to any other part of the cabinet assembly for pivotable movement between their open and closed positions, e.g. the back wall, top wall or bottom wall of the cabinet.




Various other alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention.



Claims
  • 1. A storage unit, comprising:a cabinet defining an interior; a door assembly comprising a first door section and a second door section, each of which is pivotably mounted to the cabinet for movement between an open position and a closed position, wherein the first door section comprises a first door member and a first arm secured to the first door member in a fixed angular relationship and wherein the second door section comprises a second door member and a second arm secured to the second door member in a fixed angular relationship, wherein the first and second arms are pivotably interconnected with the cabinet to provide movement of the first and second door sections, respectively, between the open and closed positions, and wherein the first and second door sections prevent access to the interior of the cabinet when in the closed position and provide access to the interior of the cabinet when in the open position; a link pivotably interconnected between the first and second arms so as to synchronize movement of the first and second door sections between the open and closed positions; and a biasing arrangement interconnected with at least one of the door sections for counterbalancing the door assembly; wherein the biasing arrangement and the first and second door sections are constructed and arranged so that the biasing arrangement applies a biasing force to the first and second door sections that biases the first and second door sections toward the open position, wherein the biasing force applied by the biasing arrangement is operable to maintain the first and second door sections in the open position when the first and second door sections are moved to the open position, and is further operable to enable the first and second door sections to remain in the closed position when the first and second door sections are moved to the closed position, and is further operable to maintain the position of the first and second door sections in position when the first and second door sections are moved to a position between the open and closed positions.
  • 2. The storage unit of claim 1, wherein the first and second arm members are pivotably mounted to the cabinet at spaced locations.
  • 3. The storage unit of claim 1, wherein the biasing arrangement comprises a spring interconnected with one of the first and second arm members, wherein the spring is operable to exert a biasing force on the arm member at a location offset from a pivot axis defined by the pivotable mounting of the arm member to the cabinet.
  • 4. The storage unit of claim 1, wherein the biasing arrangement comprises a weight mounted to one of the first and second arm members at a location offset from a pivot axis defined by the pivotable mounting of the arm member to the cabinet.
  • 5. A storage unit, comprising:a cabinet defining an open front; a first door section pivotably mounted to the cabinet, wherein the first door section comprises a first door member and a first arm secured to the first door member in a fixed angular relationship, wherein the first arm is pivotably mounted to the cabinet for pivotably mounting the first door section to the cabinet for movement relative to the cabinet between an open position and a closed position; a second door section pivotably mounted to the cabinet, wherein the second door section comprises a second door member and a second arm secured to the second door member in a fixed angular relationship, wherein the second arm is pivotably mounted to the cabinet for pivotably mounting the second door section to the cabinet for movement relative to the cabinet between an open position and a closed position; wherein the first and second door sections are together when in the closed positions to close the open front of the cabinet, and are apart when in the open positions to provide access to the open front of the cabinet; a link member pivotably interconnected between the first arm and the second arm, wherein the link member is constructed and arranged so as to move one of the door sections in response to movement of the other; and a biasing arrangement interconnected with one of the door sections for counterbalancing the weight of at least one of the door sections.
  • 6. The storage unit of claim 5, wherein the biasing arrangement and the first and second door sections are constructed and arranged so that the force of the biasing arrangement applies a biasing force to the first and second door sections that biases the first and second door sections toward the open position, wherein the biasing force applied by the biasing arrangement is operable to maintain the first and second door sections in the open position when the first and second door sections are moved to the open position, and is further operable to enable the first and second door sections to remain in the closed position when the first and second door sections are moved to the closed position, and is further operable to maintain the position of the first and second door sections when the first and second door sections are moved to a position between the open and closed positions.
  • 7. The storage unit of claim 6, wherein the link member is pivotably engaged with one of the first and second arms at a location between the open front of the cabinet and a pivot axis defined by the pivotable mounting of the arm to the cabinet, and is pivotably engaged with the other of the first and second arms at a location rearwardly of a pivot axis defined by the pivotable mounting of the other arm to the cabinet.
  • 8. The storage unit of claim 6, wherein the biasing arrangement comprises a spring interconnected between the cabinet and one of the first and second arms, wherein the spring is operable to apply a biasing force to the arm.
  • 9. The storage unit of claim 6, wherein the biasing arrangement comprises a counterweight mounted to one of the first and second arms at a location rearwardly of a pivot axis defined by the pivotable mounting of the arm to the cabinet.
  • 10. In a storage unit including a cabinet defining an open front and an upper door member, the improvement comprising an upper arm secured to the upper door member, in a fixed angular relationship and a pivot connection interposed between the upper arm and the cabinet for providing movement of the upper arm, and thereby the upper door member, about an upper pivot axis, and a lower door member and a lower arm secured together in a fixed angular relationship, wherein the lower arm is interconnected with the cabinet via a pivot connection for providing movement of the lower arm, and thereby the lower door member, about a lower pivot axis, wherein the upper and lower door members are movable between an open position providing access to the open front of the cabinet and a closed position for closing the open front of the cabinet, and a spring interconnected between the cabinet and one of the arms, and further comprising a link member interconnected between the upper arm and the lower arm, wherein the link member is operable to synchronize movement of the upper and lower door members between the open and closed positions, wherein the spring and the arm are constructed and arranged such that the spring applies a biasing force to the arm which counterbalances the weight of the door members, wherein the biasing force urges the door members toward the open position, and wherein the spring, the arms and the door members are constructed and arranged so that the biasing force applied by the spring is operable to maintain the door members in the open position when the door members is are moved to the open position, and is further operable to enable the door members to remain in the closed position when the door members are moved to the closed position, and is further operable to maintain the door members in position when the door members are moved to a position between the open and closed positions.
  • 11. The storage unit of claim 10, wherein the link member is pivotably interconnected with the upper arm at a location forwardly of the upper pivot axis, and wherein the link member is pivotably interconnected with the lower arm at a location rearwardly of the lower pivot axis.
  • 12. The storage unit of claim 10, wherein the spring comprises a linear spring having forward and rearward ends, wherein the rearward end of the spring is fixed to the cabinet and wherein the forward end of the spring is mounted to a spring mounting arrangement associated with the arm.
  • 13. The storage unit of claim 12, wherein the spring mounting arrangement associated with the arm comprises a spring mounting section that extends upwardly from the arm at a location above the pivot axis.
  • 14. The storage unit of claim 13, wherein the rearward end of the spring is interconnected with the cabinet at a location below the engagement of the forward end of the spring with the spring mounting section of the arm.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Serial No. 60/270,573, filed Feb. 22, 2001.

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Provisional Applications (1)
Number Date Country
60/270573 Feb 2001 US