US3747708A — Portable folding riser

Claim 1

Independent Claim 127 words

A folding riser, comprising, a. a pair of support frames disposed in spaced upright planes and having free lower ends adapted to rest on a floor, b. a plurality of steps having opposite ends supported on the frames at ascending levels from front to rear, c. means pivotally connecting the steps to the frames for collapsing movement of the frames about axes parallel to the steps to positions parallel to the steps, d. a brace extending between the frames and engaging at least one frame at vertically spaced positions to prevent collapsing movement of the support frames relative to the steps, e. means pivotally connecting the brace to one of the frames for collapse relative thereto, and f. means detachably connecting the brace to the other frame.

Claim 2

Dependent Claim 127 words

A folding riser, comprising, a. a pair of support frames disposed in spaced upright planes and having free lower ends adapted to rest on a floor, b. a plurality of steps having opposite ends supported on the frames at ascending levels from front to rear, c. means pivotally connecting the steps to the frames for collapsing movement of the frames about axes parallel to the steps to positions parallel to the steps, d. a brace extending between the frames and engaging at least one frame at vertically spaced positions to prevent collapsing movement of the support frames relative to the steps, e. means pivotally connecting the brace to one of the frames for collapse relative thereto, and f. means detachably connecting the brace to the other frame.

Claim 3

Dependent Claim 46 words

A folding riser as defined in claim 1, wherein the support frames are each skeletal and comprise an upright rear leg, an upright front leg, a rigid horizontal crossmember connecting lower ends of the legs, and an inclined brace connecting the rear leg and the crossmember.

Claim 4

Dependent Claim 55 words

A folding riser as defined in claim 1, wherein the means pivotally connecting the steps and the support frames comprises a plurality of hinge pins rigidly positioned on each frame beneath each seat, and a hinge plate secured to the adjacent seat with a recess capturing the hinge pin between the plate and the seat.

Claim 5

Dependent Claim 38 words

A folding riser as defined in claim 1, wherein the brace comprises a frame pivotable about an upright axis on one support frame and disposed in an upright plane parallel to the rear edge of the upper step.

Claim 6

Dependent Claim 52 words

A folding riser as defined in claim 1, wherein the last recited means comprises a spring-biased latch on said other frame for releasably holding said brace in extended position, and cooperating cam means on the brace and the latch for forcing the latch open as the brace is moved to extended position.

Claim 7

Dependent Claim 30 words

A folding riser as defined in claim 1, including a stop on said other frame abutting the brace in extended position and a pin securing the brace to the stop.

Claim 8

Dependent Claim 22 words

A folding riser as defined in claim 1, including means for releasably holding the brace in collapsed position adjacent said one frame.

Claim 9

Dependent Claim 51 words

A folding riser as defined in claim 7, wherein the last recited means comprises a spring-biased latch on the brace for releasably engaging said one frame, and cooperating cam means on said one frame and on the brace for forcing the latch open as the brace is moved to collapsed position.

Claim 10

Dependent Claim 39 words

A folding riser as defined in claim 6, wherein the brace comprises a frame pivotable about an upright axis on said one support frame and disposed in an upright plane parallel to the rear edge of the upper step.

Claim 11

Dependent Claim 173 words

A portable folding riser, comprising, a. a pair of support frames disposed in spaced parallel upright positions and having free lower ends engageable with a floor, b. a plurality of horizontal supports on each support frame at increasing heights from front to rear, c. a plurality of ascending steps having opposite ends pivotally connected to the supports for collapsing movement of the steps and frames about parallel front-to-rear axes to positions with the steps lying in a common plane and the frames lying in a common plane closely parallel to the steps, d. a brace connecting the support frames in an upright plane parallel to the rear step, e. means pivotably mounting one end of the brace about an upright axis on one of the support frames for movement to a collapsed position parallel to the frame, f. means detachably connecting the other end of the brace to the other frame, and g. a plurality of casters on the backs of the support frames for movably supporting the riser on edge when collapsed.

Claim 12

Dependent Claim 173 words

A portable folding riser, comprising, a. a pair of support frames disposed in spaced parallel upright positions and having free lower ends engageable with a floor, b. a plurality of horizontal supports on each support frame at increasing heights from front to rear, c. a plurality of ascending steps having opposite ends pivotally connected to the supports for collapsing movement of the steps and frames about parallel front-to-rear axes to positions with the steps lying in a common plane and the frames lying in a common plane closely parallel to the steps, d. a brace connecting the support frames in an upright plane parallel to the rear step, e. means pivotably mounting one end of the brace about an upright axis on one of the support frames for movement to a collapsed position parallel to the frame, f. means detachably connecting the other end of the brace to the other frame, and g. a plurality of casters on the backs of the support frames for movably supporting the riser on edge when collapsed.

Claim 13

Dependent Claim 62 words

A portable folding riser as defined in claim 10, wherein the means detachably connecting said other end of the brace to said other frame includes a yieldable latch on said other frame for releasably holding said brace against horizontal pivotal movement on said one frame in a collapsing direction, and means releasably securing the brace to said other frame against vertical movement.

Claim 14

Dependent Claim 35 words

A portable folding riser as defined in claim 10, including means for releasably holding the brace in collapsed position on said one frame including a yieldable latch on the brace releasably engaging said one frame.

Claim 15

Dependent Claim 54 words

A portable folding riser as defined in claim 10, including means pivotally connecting the steps to the frames comprising a plurality of hinge pins rigidly positioned on each frame beneath each seat, and a hinge plate secured to the adjacent seat with a recess capturing the hinge pin between the plate and the seat.

Claim 16

Dependent Claim 133 words

A folding riser, comprising, a. a pair of support frames disposed in spaced upright planes and each including an upright rear leg, an upright front leg, and a crossmember rigidly connecting the legs, said legs having free lower ends adapted to rest on a floor, b. a plurality of steps having opposite ends supported on the frames at ascending levels from front to rear, c. means pivotally connecting the steps to the frames for collapse including a plurality of hinge pins rigidly positioned on each frame beneath each seat, and a hinge plate secured to the adjacent seat with a recess capturing the hinge pin between the plate and the seat, and d. a collapsible brace releasably connecting the support frames to prevent pivotal collapse of the support frames relative to the seats.

Claim 17

Dependent Claim 133 words

A folding riser, comprising, a. a pair of support frames disposed in spaced upright planes and each including an upright rear leg, an upright front leg, and a crossmember rigidly connecting the legs, said legs having free lower ends adapted to rest on a floor, b. a plurality of steps having opposite ends supported on the frames at ascending levels from front to rear, c. means pivotally connecting the steps to the frames for collapse including a plurality of hinge pins rigidly positioned on each frame beneath each seat, and a hinge plate secured to the adjacent seat with a recess capturing the hinge pin between the plate and the seat, and d. a collapsible brace releasably connecting the support frames to prevent pivotal collapse of the support frames relative to the seats.

Claim 18

Dependent Claim 43 words

A folding riser as defined in claim 14, wherein the brace comprises a frame disposed in an upright plane parallel to the rear edge of the upper step, and pivotably mounted at vertically spaced positions on the rear leg of one support frame.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1976-07-23	1977-01-22	1977-07-24	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1980-07-23	1981-01-22	1981-07-24	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1984-07-23	1985-01-22	1985-07-24	$7700.00	Window Closed / Lapsed

Portable folding riser

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