Lightweight handle

Information

  • Patent Grant
  • 6230925
  • Patent Number
    6,230,925
  • Date Filed
    Tuesday, January 12, 1999
    25 years ago
  • Date Issued
    Tuesday, May 15, 2001
    23 years ago
Abstract
Disclosed is a light weight handle assembly adapted to transport a heavy duty container which may contain sensitive electronic components. The handle assembly of the present invention generally comprises a stationary bracket which mounts to a container wall and a movable handle pivotally connected to the bracket. The bracket is formed with an inner portion that is adapted to rotatably engage with a pair of pivoting arms extending from the movable handle so that the light weight handle may easily be assembled and disassembled. Each of the pivoting arms is formed with a movable stop member which is advantageously positioned to contact and bear against stationary stop members which are attached to or are a part of the container to which the handle is attached. The stationary stop members and movable stop members each have a substantially planar contact surface which is designed such that when the movable handle is pivoted to the lifting/operative position, the movable stop members are in contact with the at least one stationary stop member with less stress in the materials than in conventional handles. The lower stresses enable a strong handle to be made of plastic material such as polyethylene.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The invention relates to handles. More particularly, the invention relates to handles fastenable to a container and which provide a lightweight, yet strong and stable platform for carrying the container.




2. Prior Art




Handles of one kind or another have been manufactured and used for as long as there have been things to carry. In particular, container handles have experienced significant advances in design and manufacture over the years to provide hidden handles, handles that are maintained away from the container wall, handles which lock in various positions and spring loaded handles. While all of these handles are useful for their intended purposes, they have drawbacks of one kind or another such as excessive weight, excessive size, excessive expense and unacceptable generation of forces in particular areas which may not be desirable. One prior art handle provides significant reduction of stresses in the handle allowing lighter, less expensive materials to be used. This has been a great benefit to the art. Unfortunately, U.S. Pat. No. 5,461,755 is relatively large and can only be employed on larger containers. This is due in part to the size of the stationary bracket that holds the handle to the container. Reducing the size of the bracket and reconfiguring its function is the subject of this disclosure.




SUMMARY OF THE INVENTION




The above-discussed and other drawbacks and deficiencies of the prior art are overcome or alleviated by the lightweight stress reducing handle of the invention.




The handle of the invention is an extremely lightweight handle having a pre-engineered stress reducing construction in combination with handle stop capability which depends upon a feature of the container to which the handle is mounted while maintaining contact zones in stress reduced angles. The handle is even more lightweight and compact than the prior art and advantageously can be mounted on a small container as well as a large container. More particularly, the handle of the invention comprises a stationary bracket portion mountable to a wall of a container adjacent a portion of the container which provides a stop surface upon which the handle portion, pivotally mounted in said stationary bracket, may bear. The handle is engineered such that the contact plane between stop surfaces on the handle portion and the portion of the container acting as a stop surface will be approximately 45° to the mounting surface of the stationary bracket. Providing a cooperating surface designed to contact a feature of a container at a particular preset angle of about 45° significantly reduces stress in the handle and provides for substantially more longevity in the handle. Moreover, the reduced stress in the handle allows the use of cheaper, lighter and less structurally strong materials. Employing the 45° contact surface removes concern regarding the material of the container as well since the force acting thereon is significantly lower than it might otherwise be.




The handle of the invention is most preferably spring loaded and easily disassembled from a stationary bracket once such bracket is not attached to the container.




The above-discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.











BRIEF DESCRIPTION OF THE DRAWINGS




Referring now to the drawings wherein like elements are numbered alike in the several FIGURES:





FIG. 1

is a front plan view of the handle of the invention mounted on a section of container wall;





FIG. 2

is a top plan view of the handle of the invention;





FIG. 3

is a bottom plan view of the handle of the invention;





FIG. 4

is a rear plan view of the handle of the invention;





FIG. 5

is a side view of the handle of the invention in the inoperative position;





FIG. 6

is a side view in the operative position;





FIG. 7

is a perspective view of the bail of the invention separated from the bracket;





FIG. 8

is a perspective view of the bracket of the invention separated from the bail;





FIG. 9

is a cross-section view of the invention taken along section line


9





9


in

FIG. 4

;





FIG. 10

is a perspective view of the handle of the invention attached to a section of container wall;





FIG. 11

is a perspective view of the torsion spring of the invention; and





FIG. 12

is a side elevation view of the handle of the invention in the raised position which includes exemplary measurements and force vectors for one particular example of the invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




Referring to

FIG. 1

, the light weight handle assembly according to the present invention is illustrated. The handle assembly


10


generally comprises a stationary bracket


12


mounted to a container wall


14


which may be a wall of a roto-molded container or any other container. The handle assembly


10


further comprises a movable handle


16


which is pivotally connected to the stationary bracket


12


. When the stationary bracket


12


is connected to the container wall


14


, the movable handle


16


may be pivoted between an inoperative position (

FIG. 5

) and an operative position (FIG.


6


). When the stationary bracket


12


is not attached to or is removed from the container wall


14


, the movable handle


16


may be easily removed from bracket


12


. Easy removal is facilitated by bracket


12


merely trapping a portion of handle


16


(disclosed hereunder) to container wall


14


. This feature of the present invention allows the handle assembly


10


to be quickly assembled or disassembled, thereby increasing production efficiency and reducing repair time, respectively.




To stabilize the handle assembly


10


while the container is being carried by the handle, there is provided at least one stationary stop member. Handle


16


also provides two moveable stop members located advantageously on pivoting arms (further discussed hereunder) which are to contact another structure (or structures). In the preferred embodiment this is a part of the container termed protuberance


17


. The movable stop members


22


and


24


and the protuberance


17


are adapted to contact each other to thereby limit the pivotal movement of the movable handle


16


between its inoperative position (

FIG. 5

) and its operative position (FIG.


6


). As will be described more fully herein, the protuberance


17


and the movable stop members


22


and


24


contact one another at about 45° to container wall


14


. This reduces the stress in the handle allowing less expensive materials to be used.




Referring to

FIGS. 1

,


4


and


7


, the movable handle


16


comprises a hand grip


26


adapted to be comfortably grasped by a user's hand. The movable handle


16


further comprises a pair of pivoting arms


28


and


30


that extend from the hand grip


26


and which are generally parallel to each other. The movable handle


16


further comprises rotating pivot portions


32


and


34


which extend from the distal end of the pivoting arms


28


and


30


, respectively and which are generally disposed parallel to the hand grip


26


.




With reference to

FIG. 7

, the rotating pivot portions


32


and


34


comprise cylindrical portions


36


and


38


, respectively, which are adapted to freely rotate within corresponding cylindrically shaped cavity portions


40


and


42


(

FIG. 8

) extending inwardly from a rear surface


44


of the stationary bracket


12


. Cylindrical portions


36


and


38


are captured within the first and second cavity portions


40


and


42


when bracket


12


is fastened to container wall


14


. When the movable handle


16


is in its operative position (FIG.


6


), the cylindrical portions


36


and


38


are in bearing contact with their corresponding cavity portions


40


and


42


.




Still referring to

FIG. 7

, each of the rotating pivot portions


32


and


34


further comprise a semi-circularly shaped flange portion


50


protruding from respective ends of the cylindrical portions


36


and


38


which are adapted to freely rotate within corresponding cylindrically shaped cavity portions


52


which extend inwardly from the rear surface


44


of the stationary bracket


12


. When the flange portions


50


are disposed within the cavity portions


52


, the axial movement of the cylindrical portions


36


and


38


and therefore the handle is limited.




The rotating pivot portion


34


further comprises a spring support


56


disposed adjacent to and extending from the cylindrical portion


38


. The spring support portion


56


is of generally cylindrical shape and is adapted to receive a torsion spring


58


(FIG.


4


). The spring support portion


56


is rotatable within a spring attachment cavity


60


extending inward from the rear surface


44


of the stationary bracket


12


. The spring support


56


further includes a rounded square section


62


that is adapted to secure one end of the torsion spring


58


which has been wound around a square mandrel to produce square spring tang


59


. The spring configuration is illustrated in FIG.


11


. The spring and spring support


56


have been selected to reduce stress in the parts thereby creating a longer lifespan for those parts. Where prior art torsion springs have been engaged in a slot in the part around which they are disposed the slotted material tends to fracture from use. Since the square section


62


is inherently of a thicker cross section, it is better able to handle the stress. The stress is also divided over four corners as opposed to two as in the stated prior art arrangements. The other end of the torsion spring


58


is secured by spring leg


57


receivable within a channel


64


formed adjacent to the cavity


60


. The at least one stationary stop member is preferably protuberance


17


illustrated in

FIGS. 5 and 6

; alternatives being protrusions of the molded container located differently and separate structures mounted to the container wall at a predetermined location relative to the light weight handle. In each of the possible alternates the paramount point is that for the construction dictated the contact orientation for the moveable stop members is about 45° to the container wall/mounting surface of the handle of the invention when the handle is in the operative position. The movable stop members


22


and


24


are formed on an outside portion


68


of the pivoting arms


28


and


30


. In a preferred embodiment, the at least one stationary stop member supplies a contact surface


70


that is at an angle α to the bracket


12


and container wall


14


. In the preferred embodiment, the angle α is about 45 degrees. Similarly, the movable stop members


22


and


24


are each formed with a substantially planar contact surface


72


which is off-set an angle b from outside surface


68


of the pivoting arms


28


and


30


. In a preferred embodiment, the angle b is about 45 degrees. In operation, when the movable handle


16


is pivoted from its inoperative/stored position (

FIG. 5

) to is operative/lifting position (FIG.


6


), the movable stop members


22


and


24


are brought into substantial contact with the stationary stop member


17


. As such, the pivotal movement of the movable handle


16


between its inoperative position (

FIG. 5

) and its operative position (

FIG. 6

) is about 90 degrees. The contact surfaces


70


and


72


meet at an angle of about 45° to the plane of container wall


14


. This is beneficial because it reduces shear stress in the handle and allows the use of softer less expensive materials.




Referring to

FIGS. 2

,


4


,


5


and


6


, the stationary bracket


12


also comprises a plurality of mounting lugs or bosses


82


disposed on the rear surface


44


of bracket


12


. In the preferred embodiment, the mounting lugs or bosses


82


extend from the rear surface


44


and provide shear strength between the bracket


12


and the container wall


14


. In this regard, the hand gripping portion


26


of the movable handle


16


may be upwardly displaced an angle c from a bottom surface


86


of the pivoting arms


28


and


30


to thereby facilitate initial grasping of the hand gripping portion


26


. In the preferred embodiment the angle c is in the range of about 15°-25° and preferably is about 19°. The mounting lugs


82


may further comprise openings


84


adapted to receive a suitable fastener such as a self-tapping screw and the like. Such fasteners are loaded in tension only, and sealing against air passage is accomplished by the employment of rubber-faced washers under the heads of the fasteners.




The stress-lowering improvements of the handle of the present invention may best be demonstrated with reference to FIG.


6


. As shown, the handle


16


is placed in its operative/lifting position by an upward force F


L


applied to the hand grip


26


. As said handle


16


has two pivoting arms


28


and


30


, the upward force on each arm


28


and


30


is F


L


/2. Upward rotation beyond 90° is prevented by a compressive stop force F


s


in the contact area between the movable stop members


22


,


24


and stationary stop member


17


and a shear force in the pivot F


p


. For a specific magnitude of F


L


, the stop force F


s


is inversely proportional to the moment arm J. Thus, to minimize F


s


, the moment arm J must be as large as possible. This is controlled by the thickness t of the bracket


12


and the diameter of the pivot portions


32


and


34


. When the thickness of the bracket


12


and the handle


16


are approximately the same, the moment arm J will be maximized when the angle of the plane between the axis of the pivot portions


32


and


34


and the stop areas


18


,


20


,


22


and


24


is 45° relative to the horizontal. In the preferred embodiment where said angle is 45°, said moment arm J is approximately 1.5 times greater than when contact between the movable stop members and stationary stop member is horizontal. Thus, for the same lifting force F


L


, the compressive stress in the stop member area of the handle


16


is approximately 33% less. This stress-lowering improvement in the handle


16


makes it possible to produce said handle from polyethylene and other low-cost materials such as polypropylene and acrylonitrile-butadiene-styrene (ABS). Polyethylene is preferred due to its nearly inert properties.




As will be clear to those skilled in the art, a change in the ratio of bracket thickness to handle thickness will dictate a change in the angle for maximizing the moment arm J. It will also be understood that although the preferred angle of 45° for the construction dictated is optimum, departures from this angle reduce efficiency in increments. Thus, as long as the angle selected is near 45°, a substantial amount of the benefit of the invention will be retained. Preferably, the range of angles for the contact surfaces should be about 38° to about 52° to the container wall with a more preferred range of about 42° to about 48°. It will be understood by one of ordinary skill in the art, subsequent to exposure to this disclosure, that the force advantage of the present invention deteriorates in each direction of angle when moving away from the optimum of about 45°. Referring to

FIG. 12

, one example of the invention is provided with measurements taken and forces shown. The calculations set forth hereunder demonstrate the very low pivot and stop forces associated with the handle of the invention. The formulae are intended to be read in conjunction with FIG.


12


:











F
L






3.43

=



F

s3







1.19





cos





44.5

°

=
0.713








F
s

=


2.88


F
L






sin





44.5

°

=
0.701








F
P

=




(

F
PH3

)

2

+


(

F
PV3

)

2










F
PH3

=



F
s3






cos





44.5

°

=


2.88






F
L






0.713

=

2.05






F
L












P
PH3

+

F
L


=


F
S3







sin
θ












P
VH3

=








F
S3






sin





44.5

°

-

F
L


=



2.88






F
L






0.701

-

F
L


=


2.01


F
L


-

F
L

-

F
L










=





1.01


F
L









F
P

=









(

2.05


F
L


)

2

+


(

1.01


F
L


)

2



=



F
L








4.20
+
1.02



=

2.28






F
L




















The stationary bracket


12


and the movable handle


16


may be made from a variety of materials, including but not limited to, polyethylene or any high strength thermoplastic material. The handles of the invention uniquely may be made of polyethylene which if used in a configuration not adhering to the parameters of the invention is generally not structurally strong enough to act as a functional handle. To realize additional weight reductions and to reduce material costs and molding time, material from the stationary bracket


12


and the movable handle


16


may be removed in various places without significantly reducing the load/strength requirements of the components. By way of example only, the pivoting arms


28


and


30


may be formed with cut-outs


76


(

FIG. 5

) which eliminate a large amount of material and ribs


78


may be formed to maintain the strength requirements. Similarly, the hand grip


26


may be formed with a hollow inner portion


80


thereby also removing a significant amount of material.




Except for the torsion spring


58


, protuberance on the container and mounting bolts (not shown), all of features of the handle assembly


10


heretofore described are formed integral to either the stationary bracket


12


or the movable handle


16


. (Stationary stop members other than those molded as part of the container are additional structures). This feature provides a handle assembly


10


that is compatible with high production environments and which is reliable and durable. The stationary bracket


12


and the movable handle


16


may be manufactured by conventional molding processes suitable for use with thermoplastic materials.




While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.



Claims
  • 1. A handle assembly disposed on a container wall for lifting and transporting said container, the handle assembly comprising:a stationary bracket affixed to the container wall, said bracket having an inner and outer portions; a movable handle comprising a hand grip and first and second arms extending from said handgrip, each of said first and second arms including an outer portion and a pivot portion substantially parallel to said hand grip, each of said pivot portions being rotatable within said inner portion of said inner bracket so that said movable handle may be pivoted between a first position and a second position; a spring support extending axially from said pivot portion of said first arm, said spring support having a substantially square section disposed on a distal end thereof; and a coiled torsion spring disposed about said spring support having a first end and a second end, said first end being formed as a substantially square tang for mating engagement with an outer periphery of said substantially square section, and said second end being attached to said stationary bracket.
  • 2. The handle assembly of claim 1, wherein said inner portion of said stationary bracket includes first and second retainers for retaining said first and second pivot portions of said movable handle.
  • 3. The handle assembly of claim 1, wherein each of said pivot portions of said movable handle further includes a cylindrical portion adapted to rotate within said inner portion of said stationary bracket.
  • 4. The handle assembly of claim 3, wherein each of said pivot portions of said movable handle further include a flange portion extending outwardly from said cylindrical portion so as to limit the axial movement of said pivot portion within said inner portion of said stationary bracket.
  • 5. The handle assembly of claim 4, wherein said inner portion of said stationary bracket comprises a first cavity for rotatably receiving said first pivot portion of said first arm and a second cavity for rotatably receiving said second pivot portion of said second arm, said first retainer being disposed in said first cavity and said second retainer being disposed in said second cavity.
  • 6. The handle assembly of claim 5, wherein said inner portion of said stationary bracket further includes a third cavity for receiving said flange portion of said first pivot portion of said first arm and a fourth cavity for receiving said flange portion of said second pivot portion of said second arm.
  • 7. A lightweight handle for a container comprising:a bracket having at least one axial cavity, said bracket being attachable to a container; at least one stationary stop member connected with said container; a handle comprising a hand grip and two arms extending from said hand grip, said arms further including pivot portions for pivotable engagement with said bracket, said arms further including stop members each having a contact surface matable with said at least one stationary stop member; a spring support extending axially from one of said pivot portions of said arms, said spring support having a substantially square section disposed on a distal end thereof; and a coiled torsion spring disposed about said spring support having a first end and a second end, said first end being formed as a substantially square tang for mating engagement with an outer periphery of said substantially square section, and said second end being attached to said bracket.
  • 8. A light weight handle for a container as claimed in claim 7 wherein said pivot portions are generally cylindrical extensions of said arms extending from each arm generally parallel to said hand grip and toward one another.
  • 9. A light weight handle for a container as claimed in claim 7 wherein said at least one stationary stop member is a feature of the container.
  • 10. A light weight handle for a container as claimed in claim 7 wherein said at least one stationary stop member is a separate structure mounted to said container.
  • 11. A light weight handle for a container as claimed in claim 7 wherein said at least one stationary stop member is two stop members.
  • 12. A light weight handle for a container as claimed in claim 11 wherein said members are separate structures mounted to said container.
  • 13. A light weight handle for a container as claimed in claim 11 wherein said members are features of the container.
  • 14. A lightweight handle in combination with a container comprising:a container; a mounting surface on said container, said surface being recessed to provide at leas t an upper edge that is raised relative to said mounting surface; a handle including a bracket and a movable bail mounted on said container adjacent said upper edge of said mounting surface; at least one stop surface on said movable bail, said stop surface being located to contact said container at a predetermined location to reduce stress in the handle; a spring support extending from one end of said handle, said spring support having a substantially square section disposed on a distal end thereof; and a coiled torsion spring disposed about said spring support having a first end and a second end, said first end being formed as a substantially square tang for mating engagement with an outer periphery of said substantially square section, and said second end being attached to said bracket.
  • 15. A light weight handle as claimed in claim 14 wherein said predetermined location is a protuberance at the upper periphery of the mounting surface.
  • 16. A light weight handle as claimed in claim 14 wherein said at least one stop surface is two surfaces.
  • 17. A light weight handle as claimed in claim 14 wherein said predetermined location is one which contacts said at least one stop surface at an angle of about 45° to the container mounting surface.
  • 18. A light weight handle as claimed in claim 15 wherein said predetermined location is two locations, and said at least one stop surface is two stop surfaces on said rotatable handle, both stop surfaces being maintained at about 45° to the container mounting surfaces.
  • 19. A light weight handle assembly adapted to be recessed within a recess in a container wall comprising:a) a bracket attachable to a container wall; b) a handle having a handgrip portion and two arms extending from said handgrip portion, said arms being engageable within said bracket on at least one pivot; c) at least one moveable stop associated with said handle; d) at least one stationary stop wherein said at least one stationary stop and said at least on moveable stop come into contact with one another at a plane passing through an axis of said at least one pivot and tangent to an upper edge of said recess; e) a spring support extending axially from said at least one pivot, said spring support having a substantially square section disposed on a distal end thereof; and f) a coiled torsion spring disposed about said spring support having a first end and a second end, said first end being formed as a substantially square tang for mating engagement with an outer periphery of said substantially square section, and said second end being attached to said bracket.
  • 20. A lightweight handle assembly adapted to be recessed in a recess in a container wall comprising:a) a bracket attachable to a container wall; b) at least one stationary stop associated with said container; c) a handle having a handgrip portion and two arms extending therefrom said arms being pivotally attachable with said bracket; d) at least one moveable stop associated with said handle, said at least one moveable stop contacting said at least one stationary stop in the outer plane of said container; e) a spring support extending axially from one of said two arms, said spring support having a substantially square section disposed on a distal end thereof; and f) a coiled torsion spring disposed about said spring support having a first end and a second end, said first end being formed as a substantially square tang for mating engagement with an outer periphery of said substantially square section, and said second end being attached to said bracket.
  • 21. A lightweight handle assembly adapted to be recessed into a recess in a container comprising:a) a bracket attachable to a wall of said container in said recess; b) at least one stationary stop associated with said container; c) a handle having a handgrip and two arms extending therefrom said arms being pivotally attachable with said bracket and wherein a pivot is located adjacent said wall upon which said bracket is attached; d) at least one moveable stop associated with said handle, adjacent an outer plane of said handle when mounted on said container, said plane being coplanar with an outer plane of said container, said at least one moveable stop contacting said at least one stationary stop in the outer plane of said container; e) a spring support extending axially from one of said two arms said spring support having a substantially square section disposed on a distal end thereof; and f) a coiled torsion spring disposed about said spring support having a first end and a second end, said first end being formed as a substantially square tang for mating engagement with an outer periphery of said substantially square section, and said second end being attached to said bracket.
CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of an earlier filing date from U.S. Provisional Application Ser. No. 60/071,448, filed Jan. 13, 1998.

US Referenced Citations (29)
Number Name Date Kind
337889 Taylor Mar 1886
630886 Held Aug 1899
644119 Witt Feb 1900
747570 Pickop Dec 1903
908285 Lewis Dec 1908
1940099 Preston Dec 1933
2088476 Kemper Jul 1937
2254506 Wheary, Jr. Sep 1941
2401399 Akers Jun 1946
2436598 Pastor et al. Feb 1948
2517369 Wolfson Aug 1950
2767424 Knuepfer Oct 1956
3248750 Black May 1966
3464586 Hitzeroth Sep 1969
3538538 Field Nov 1970
3562849 Brayshaw Feb 1971
3699611 Johnson Oct 1972
3804290 Billman Apr 1974
3813729 Szabo et al. Jun 1974
3924775 Andreaggi et al. Dec 1975
4157763 Betlejenski et al. Jun 1979
4196821 Teti, Jr. et al. Apr 1980
4223421 Wassenaar Sep 1980
4284202 Barstow, Jr. Aug 1981
4475415 Yamamoto Oct 1984
4544050 Seynhaeve Oct 1985
5012553 Hardigg et al. May 1991
5226553 Fiore Jul 1993
5461755 Hardigg et al. Oct 1995
Provisional Applications (1)
Number Date Country
60/071448 Jan 1998 US