← Back to Patent Explorer
US4246677A Expired / Lapsed US ⏱️ 0.0 years remaining

Cart caster

Assignee: COLSON Co
•
Filing: 1979-05-14
•
Granted: 1981-01-27
•
Expires: 1999-05-14
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A cart caster having an improved self-centering structure for causing the caster wheel to have a preselected alignment when elevated from a subjacent support surface. The self-aligning structure includes a cam, a cam follower, and a biasing element cooperatively causing the caster wheel to move to a preselected position about the caster axis when load is removed from the wheel as by lifting of the cart. The aligning structure may include a plurality of alignment portions permitting the wheel to be automatically brought to any one of a plurality of different positions about the caster axis, such as to either a fore or aft direction relative to the cart.

Inventors

  • 👤 Joe R. Downing
  • 👤 Leslie G. Williams

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 06:46
CPC Classifications
B; B60; B60B; B60B33/00; B60B33/02

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 221 words
A cart caster comprising: a base; a generally elliptical plate defining a midportion and having a peripheral elliptical camming surface including a pair of centering portions disposed at opposite ends of the minor axis of the cam plate, and rise portions extending away from each of said centering portions and progressively further away from said midportion to the opposite ends of the major axis of the cam plate; means mounting said cam plate to said base for rotation about an axis at said midportion; a wheel; a pair of wheel supports carried by said cam plate and rotatably mounting said wheel therebetween; a cam follower engaging said camming surface; and biasing means urging said cam follower against said camming surface to urge said cam plate rotatively about said axis of rotation to a position wherein said cam follower engages a centering portion, said cam follower comprising a carrier having a midportion and opposite end portions, a roller rotatively carried on one end portion of the carrier, and means pivotally mounting the opposite end portion of the carrier to said base, said biasing means comprising a spring acting on said midportion of said carrier to urge said roller against said camming surface at an angle to a line from said axis of rotation to said centering portion of the camming surface thereof.
Claim 2
Dependent Claim 221 words
A cart caster comprising: a base; a generally elliptical plate defining a midportion and having a peripheral elliptical camming surface including a pair of centering portions disposed at opposite ends of the minor axis of the cam plate, and rise portions extending away from each of said centering portions and progressively further away from said midportion to the opposite ends of the major axis of the cam plate; means mounting said cam plate to said base for rotation about an axis at said midportion; a wheel; a pair of wheel supports carried by said cam plate and rotatably mounting said wheel therebetween; a cam follower engaging said camming surface; and biasing means urging said cam follower against said camming surface to urge said cam plate rotatively about said axis of rotation to a position wherein said cam follower engages a centering portion, said cam follower comprising a carrier having a midportion and opposite end portions, a roller rotatively carried on one end portion of the carrier, and means pivotally mounting the opposite end portion of the carrier to said base, said biasing means comprising a spring acting on said midportion of said carrier to urge said roller against said camming surface at an angle to a line from said axis of rotation to said centering portion of the camming surface thereof.
Claim 3
Dependent Claim 20 words
The cart caster of claim 1 wherein each of said centering portions defines a detent in said peripheral camming surface.

References Cited (Backward Citations)

US1896234A Cited
US2525362A Cited
US2481948A Cited
US2634986A Cited
US3075233A Cited
US3924292A Cited
US4028773A Cited
CH607958A5 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-01-27 1984-07-28 1985-01-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-01-27 1988-07-28 1989-01-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-01-27 1992-07-28 1993-01-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag