Step stool

Information

  • Patent Grant
  • 6550579
  • Patent Number
    6,550,579
  • Date Filed
    Friday, August 10, 2001
    23 years ago
  • Date Issued
    Tuesday, April 22, 2003
    22 years ago
Abstract
A method for assembling a step stool includes the step of providing a frame including a front leg and a rear leg coupled to the front leg for pivotable movement between an opened use position and a collapsed storage position, a step coupled to the front leg for pivotable movement between a horizontal use position and a storage position, and a link including a body, a pivot coupled to the body and the step, and a connector coupled to the body. The method further includes the step of snapping the connector into engagement with the rear leg for movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.
Description




BACKGROUND AND SUMMARY OF THE INVENTION




The present invention relates to a step stool, and particularly to a folding step stool including legs that fold between an opened use position and a collapsed storage position. More particularly, the present invention relates to a link coupled to the rear leg and a step of the step stool to coordinate movement of the rear leg and the step.




Step stools have a frame and one or more steps that individuals use for elevation when reaching for objects, painting walls, or any everyday task where extra elevation would be helpful. Step stool frames are often foldable for ease of storage while the step stool is not being used.




According to the disclosure, a method of assembling a step stool includes the steps of providing a frame including a front leg and a rear leg coupled to the front leg for pivotable movement between an opened use position and a collapsed storage position, a step coupled to the front leg for pivotable movement between a horizontal use position and a storage position, and a link including a body, a pivot coupled to the body and the step, and a connector coupled to the body. The method of assembly further includes the step of snapping the connector into engagement with the rear leg for movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.




In preferred embodiments, the link includes means for coupling the body to a strut of the rear leg upon pivoting the body about a pivot axis defined by the pivot in a plane perpendicular to a strut of the rear leg. The coupling means includes the connector and another connector. Each connector includes a hook that is coupled to the body and formed to include a channel sized to receive the strut and a detent coupled to the hook to retain the strut in the channel upon snapping the connector into engagement with the strut for movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.




Additional features of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.











BRIEF DESCRIPTION OF THE DRAWINGS




The detailed description particularly refers to the accompanying figures in which:





FIG. 1

is a perspective view of a step stool including a front leg, a rear leg coupled to the front leg in an opened use position, and top and bottom steps positioned in a horizontal use position;





FIG. 2

is a rear elevation view taken along the line


2





2


of

FIG. 1

showing the rear leg including a horizontal strut and the step stool also including a link coupled to the strut;





FIG. 3

is a side elevation view of the step stool of

FIG. 1

showing the front and rear legs positioned in a closed storage position and the steps positioned in a closed position;





FIG. 4

is a rear elevation view taken along the line


4





4


of

FIG. 3

showing the front and rear legs positioned in the closed storage position, the steps position in the closed position, and the link coupled to the top step and the strut;





FIG. 5

is a perspective view of the step stool of

FIG. 1

, with portions broken away, showing the link moving the rear leg toward its closed storage position (as represented by a thick arrow on the step) in response to movement of the step toward its closed position (as represented by a thick arrow on the rear leg);





FIG. 6

is a perspective view of the link of

FIGS. 2

,


4


, and


5


showing the link including a body, a pair of connectors coupled to the body, and a pair of pivots coupled to the body;





FIG. 7

is a perspective view of the step stool, with portions broken away, showing the front and rear legs positioned in their opened use position, the top step positioned in its horizontal use position, and the link coupled to the strut and the top step;





FIG. 8

is a side sectional view taken along line


8





8


of

FIG. 6

showing one of the pivots coupled to the step and a force (represented by a thick arrow) pressing one of the connectors onto the strut;





FIG. 9

is a side sectional view similar to

FIG. 8

showing the strut positioned to lie in a channel formed by the connector to couple the connector to the strut; and





FIG. 10

is a top plan view of the link of

FIG. 9

showing the two connectors coupled to the strut and the two pivots coupled to the top step and configured to flex slightly inwardly (as represented by arrows) to allow snap engagement of the pivots with the step.











DETAILED DESCRIPTION OF THE DRAWINGS




A foldable step stool


10


includes a frame


12


having a front leg


14


, a rear leg


16


including a strut


18


, a top step


20


, and a monolithic link


22


coupled to step


20


and strut


18


to coordinate movement of step


20


and rear leg


16


, as shown, for example, in

FIGS. 1-5

. Link


22


is configured to be coupled to strut


18


and step


20


readily by snap engagement of link


22


with strut


18


and step


20


during assembly of step stool


10


, as shown, for example, in

FIGS. 8-10

.




Frame


12


of step stool


10


is foldable between an opened use position, a shown, for example, in

FIGS. 1

,


2


, and


7


, and a closed or collapsed storage position, as shown, for example, in

FIGS. 3 and 4

. Top ends of rear leg


16


are coupled to front leg


14


for pivotable movement of rear leg


16


relative to front leg


14


between the opened use and closed storage positions. In the opened use position, a bottom end of rear leg


16


is spaced-apart from a bottom end of front leg


14


. In the closed storage position, the bottom ends of front and rear legs


14


,


16


are positioned adjacent to one another.




Front leg


14


includes a pair of leg members


24


, as shown, for example, in

FIGS. 1-5

and


7


. Each of top step


20


and a bottom step


25


is coupled to leg members


24


for pivotable movement between a horizontal use position and a storage position. Top step


20


is configured to pivot about a pivot axis


26


between its horizontal use position and its storage position.




Rear leg


16


includes a pair of leg member


28


, as shown, for example, in

FIGS. 1-5

and


7


. Strut


18


is coupled to leg members


28


.




Top step


20


is formed to include a pair of outer notches


30


and a pair of inner notches


32


, as shown, for example, in FIG.


5


. Strut


18


is positioned to lie in notches


30


,


32


for engagement with step


20


when top step


20


is positioned in its horizontal use position and rear leg


16


is positioned in its opened use position.




Link


22


is coupled to step


20


to move rear leg


16


between the opened use position and the closed storage position in response to movement of step


20


between the horizontal use position and the storage position, as shown, for example, in

FIGS. 4

,


5


and


7


-


10


. Link


22


could also be used to move step


20


between the horizontal use position and the storage position in response to movement of rear leg


16


between the opened use position and the closed storage position.




Link


22


includes a body


34


, a pair of connectors


36


coupled to body


34


and strut


18


, and a pair of pivots


38


coupled to body


34


and step


20


. Body


34


includes a first side


40


, a second side


42


coupled to first side


40


, a third side


44


coupled to second side


42


, and a fourth side


46


coupled to third side


44


and first side


40


. Connectors


36


are coupled to first side


40


. Pivots


38


are coupled to third side


44


.




Body


34


further includes a planar web


48


bounded by the four sides


40


,


42


,


44


,


46


, as shown, for example, in

FIGS. 6 and 10

. Body


34


further includes a pair of stiffening ribs


50


coupled to web


48


.




Connectors


36


are similar to one another in structure and function. Thus, the description of one of connectors


36


applies to the other of connectors


36


. Connectors


36


provides means for coupling body


34


to strut


18


.




Connector


36


includes a hook


52


coupled to first side


40


of body


34


and a detent


54


coupled to hook


52


, as shown, for example, in FIGS.


6


and


8


-


10


. Hook


52


is formed to include a channel


56


to receive strut


18


therein. Hook


52


includes an arm


58


coupled to first side


40


of body


34


and an arch


60


coupled to arm


58


at a junction


62


of arm


58


and arch


60


. Detent


54


is coupled to junction


62


. Arch


60


includes a concave surface


64


that engages strut


18


when strut


18


is positioned in channel


56


. Strut


18


slides against concave surface


64


to rotate within channel


56


during movement of rear leg


16


between the opened use and closed storage positions.




Arm


58


and arch


60


cooperate to define a first or outer side wall


66


, a second or inner side wall


68


, and an intermediate wall


70


coupled to outer and inner side walls


66


,


68


to extend therebetween, as shown, for example, in FIGS.


6


and


8


-


10


. Walls


66


,


68


,


70


are coupled to first side


40


of body


34


. Detent


54


is coupled to intermediate wall


70


and is spaced apart from outer and inner side walls


66


,


68


. Intermediate wall


70


is formed to include an aperture


72


.




Detent


54


is coupled to hook


52


to retain strut


18


in channel


56


, as shown, for example, in

FIGS. 8-10

. Detent


54


includes a concave surface


65


that faces toward strut


18


when strut


18


is positioned in channel


56


.




Detent


54


farther includes a convex cam surface


74


that faces away from concave surface


65


. Cam surface


74


engages strut


18


upon snapping strut


18


into channel


56


during assembly of step stool


10


, as shown, for example, in FIG.


8


and discussed below.




Pivots


38


are similar to one another in structure and function. Thus, the description of one of pivots


38


applies to the other of pivots


38


. Pivots


38


provide means for coupling body


34


to step


20


.




Pivot


38


includes an arm


76


that is coupled to third side


44


of body


34


and engages step


20


and an X-shaped boss


78


coupled to arm


76


, as shown, for example, in FIGS.


6


and


8


-


10


. Arms


76


curve slightly away from one another as they extend away from third side


44


.




Step


20


is formed to include a pair of apertures


80


, as shown, for example, in

FIGS. 7 and 10

. Each boss


78


extends into one of apertures


80


and is configured to engage the edge of step


20


that forms respective aperture


80


. Bosses


78


cooperate to define a pivot axis


82


about which link


22


pivots during movement of rear leg


16


between its opened use and closed storage positions and movement of step


20


between its horizontal use and storage positions.




Arm


76


includes a first wall


84


and a second wall


86


coupled to first wall


84


in perpendicular relation thereto, as shown, for example, in FIGS.


6


and


8


-


10


. First wall


84


includes an outer surface


88


and an inner surface


90


. Outer surface


88


engages step


20


. Boss


78


is coupled to outer surface


88


. Inner surface


90


faces away from outer surface


88


. Second wall


86


is coupled to inner surface


90


in spaced-apart relation to step


20


and includes an incline


140


.




First wall


84


further includes a stem


92


coupled to third side


44


of body


34


and a disk


94


coupled to stem


92


and boss


78


, as shown, for example, in FIGS.


6


and


8


-


10


. Stem


92


includes a first edge


96


and a second edge


98


spaced apart from first edge


96


. Disk


94


includes a circular edge


100


coupled to first and second edges


96


,


98


. First and second edges


96


,


98


cooperate to define a width


110


therebetween. Circular edge


100


defines a diameter


112


that is greater than width


110


. Circular edge


100


is configured to allow pivot


38


to pivot about pivot axis


82


without step


20


interfering with disk


94


.




Step stool


10


further includes a pair of step links


114


, as shown, for example, in

FIGS. 1

,


5


, and


7


. Each step link


114


is coupled to top step


20


and bottom step


25


for pivotable movement relative to each step


20


,


25


. Step links


114


are configured to pivot bottom step


25


between a horizontal use position and a closed position in response to movement of top step


20


between its horizontal use position and its closed position.




Step stool


10


further includes a latch


116


coupled to top step


20


, as shown, for example, in

FIGS. 1-5

,


7


, and


10


. A latch similar to latch


116


is disclosed in U.S. patent application Ser. No. 09/762,537, filed Feb. 8, 2001, the disclosure of which is hereby incorporated by reference herein. Latch


116


includes a platform


118


including a finger grip portion


120


, and a hook


122


coupled to platform


118


. Latch


116


includes a pair of springs (not shown). Each spring engages top step


20


and one of a pair of spring housings


126


of latch


116


to bias latch


116


toward strut


118


. Hook


122


includes a cam surface


128


that engages strut


18


upon movement of step


20


from its storage position to its horizontal use position. Latch


116


is configured to pivot about a pivot axis between a latched position and a release position.




Connectors


38


and body


34


cooperate to define a space


130


, as shown, for example, in

FIGS. 6 and 10

. Hook


122


of latch


116


is positioned to lie in space


130


when latch


116


is in its latched position.




During assembly of step stool


10


, link


22


is snapped into engagement with strut


18


and top step


20


for movement of rear leg


16


from its opened use position to its closed storage position in response to movement of step


20


from its horizontal use position to its storage position. In particular, connectors


36


are snapped into engagement with strut


18


and pivots


38


are snapped into engagement with step


20


to allow step stool


10


to be readily assembled and to limit expenses associated with manufacturing step stool


10


.




Each boss


78


is inserted into one of apertures


80


to snap pivots


38


into engagement with step


20


, as shown, for example, in FIG.


10


. This causes arms


76


of pivots


78


to engage step


20


. Pivots


38


are configured to flex slightly toward one another as pivots


38


are positioned for insertion of bosses


78


into apertures


80


.




Link


22


is pivoted about pivot axis


82


in a plane transverse to strut


18


to snap connectors


36


into engagement with strut


18


, as shown, for example, in FIG.


8


. Link


22


is pivoted in direction


134


so that cam surfaces


74


of detents


54


and edges


132


of arches


60


engage strut


18


. Cam surfaces


74


and edges


132


are pressed against strut


18


by a force


136


so that each cam surface


74


slides against strut


18


and each edge


132


moves away from respective detent


54


in direction


138


to allow strut


18


to move past detents


54


into channels


56


. Connectors


36


can be snapped onto strut


18


simultaneously or one at a time. Once strut


18


is positioned in channels


56


, concave surfaces


64


of arches


60


engage strut


18


and concave surfaces


65


of detents


54


face toward strut


18


to retain strut


18


in channels


56


.




Although the invention has been disclosed in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.



Claims
  • 1. A method of assembling a step stool, the method comprising the steps ofproviding a frame including a front leg and a rear leg coupled to the front leg for pivotable movement between an opened use position and a collapsed storage position, a step coupled to the front leg for pivotable movement between a horizontal use position and a storage position, and a link including a body, a pivot coupled to the body and the step, and a connector formed to include a channel coupled to the body, and snapping the connector into engagement with the rear leg enabling movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position and retaining the strut in the channel during movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.
  • 2. The method of claim 1, wherein the providing step includes providing the rear leg with a strut and the connector with a hook coupled to the body and formed to include a channel and the snapping step includes snapping the strut into the channel.
  • 3. The method of claim 2, wherein the providing step includes providing the connector with a detent coupled to the hook and the snapping step includes pressing the detent into engagement with the strut.
  • 4. The method of claim 3, wherein the providing step includes providing the hook with an edge spaced apart from the detent and the snapping step includes pressing the edge into engagement with the strut while pressing the detent into engagement with the strut.
  • 5. The method of claim 4, wherein the snapping step includes moving the edge away from the detent to allow the strut to move past the detent into the channel.
  • 6. The method of claim 3, wherein the providing step includes providing the detent with a cam surface and the snapping step includes sliding the strut against the cam surface into the channel.
  • 7. The method of claim 1, wherein the providing step includes providing another connector coupled to the body and the snapping step includes snapping the other connector into engagement with the rear leg for movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.
  • 8. The step stool of claim 7, wherein the providing step includes providing each of the connector and the other connector with an arm coupled to the body, an arch coupled to the arm at a junction and formed to include a channel, and a detent coupled to the junction and the snapping step includes sliding the strut against each detent and each arch into each channel.
  • 9. The step stool of claim 7, wherein the providing step includes providing another pivot coupled to the body and further comprising the step of snapping the pivot and the other pivot into engagement with the step.
  • 10. The step stool of claim 1, further comprising the step of snapping the pivot into engagement with the step for movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.
  • 11. A step stool comprisinga frame including a front leg and a rear leg coupled to the front leg for pivotable movement between an opened use position and a collapsed storage position, the rear leg including a strut, a step coupled to the front leg for pivotable movement between a horizontal use position and a storage position, and a link including a body, a pivot that is coupled to the body and the step and defines a pivot axis, and means for coupling the body to the strut in a channel upon pivoting the body about the pivot axis in a plane perpendicular to the strut retaining the strut in the channel during movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.
  • 12. The step stool of claim 11, wherein the coupling means includes a connector including a hook coupled to the body and formed to include a channel sized to receive the strut therein and a detent coupled to the hook to retain the strut in the channel.
  • 13. The step stool of claim 12, wherein the hook includes an arm coupled to the body and an arch coupled to the arm and formed to include the channel.
  • 14. The step stool of claim 13, wherein the arch includes a concave surface that engages the strut when the strut is positioned in the channel.
  • 15. The step stool of claim 13, wherein the arm is coupled to the arch at a junction and the detent is coupled to the junction.
  • 16. The step stool of claim 12, wherein the hook includes a first side wall, a second side wall spaced apart from the first side wall, and an intermediate wall coupled to the first and second side walls, the first and second side walls and the intermediate wall are coupled to the body, and the detent is coupled to the intermediate wall.
  • 17. The step stool of claim 12, wherein the detent includes a concave surface that faces toward the strut when the strut is positioned in the channel and a convex cam surface that faces away from the concave surface and is configured to engage the strut when the strut is positioned in the channel.
  • 18. The step stool of claim 12, wherein the coupling means further includes another connector including a hook coupled to the body and formed to include a channel sized to receive the strut therein and a detent coupled to the hook of the other connector to retain the strut in the channel.
  • 19. The step stool of claim 18, further comprising a latch that is coupled to the step and engages the strut when the rear leg is positioned in its opened use position to lock the rear leg in its opened use position, and wherein the hook of the connector, the hook of the other connector, and the body cooperate to define a space in which the latch is positioned when the latch engages the strut.
  • 20. A step stool comprisinga frame including a front leg and a rear leg coupled to the front leg for pivotable movement between an opened use position and a collapsed storage position, the rear leg including a strut, a step coupled to the front leg for pivotable movement between a horizontal use position and a storage position, and a link including a body, a pivot coupled to the body, and a connector coupled to the body, the connector including a hook coupled to the body and formed to include a channel sized to receive the strut and a detent coupled to the hook retaining the strut in the channel upon snapping the connector into engagement with the strut retaining the strut in the channel during movement of the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.
  • 21. The step stool of claim 20, wherein the hook includes an arm coupled to the body and an arch coupled to the arm and formed to include the channel.
  • 22. The step stool of claim 21, wherein the arch includes a concave surface that engages the strut.
  • 23. The step stool of claim 21, wherein the arm is coupled to the arch at a junction and the detent is coupled to the junction.
  • 24. The step stool of claim 21, wherein the hook includes a first side wall, a second side wall spaced apart from the first side wall, and an intermediate wall coupled to the first and second side walls and the first and second side walls and the intermediate wall are coupled to the body.
  • 25. The step stool of claim 24, wherein the detent is coupled to the intermediate wall and spaced apart from the first and second side walls.
  • 26. The step stool of claim 21, wherein the detent includes a concave surface that faces toward the strut when the strut is positioned in the channel.
  • 27. The step stool of claim 26, wherein the detent includes a convex cam surface that faces away from the concave surface and is configured to engage the strut upon snapping the strut into the channel.
  • 28. The step stool of claim 21, further comprising another pivot coupled to the body and the step and another connector including another hook coupled to the body and formed to include another channel sized to receive the strut and the other detent coupled to the other hook to retain the strut in the other channel upon snapping the other connector into engagement with the strut.
  • 29. The step stool of claim 28, wherein the body includes a first side, a second side coupled to the first side, a third side coupled to the second side, and a fourth side coupled to the third side and the first side, the hook and the other hook are coupled to the first side, and the pivot and the other pivot are coupled to the third side.
  • 30. The step stool of claim 28, further comprising a latch that is coupled to the step and engages the strut when the rear leg is positioned in its opened use position to lock the rear leg in its opened use position, and wherein the hook, the other hook, and the body cooperate to define a space in which the latch is positioned when the rear leg is positioned in its opened use position.
  • 31. The step stool of claim 21, wherein the pivot is formed to include means for snapping the pivot into engagement with the step to move the rear leg from its opened use position to its closed storage position in response to movement of the step from its horizontal use position to its storage position.
CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 60/224,595, filed Aug. 11, 2000, which is expressly incorporated by reference herein.

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Entry
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Provisional Applications (1)
Number Date Country
60/224595 Aug 2000 US