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US4779475A Expired / Lapsed US ⏱️ 0.0 years remaining

Key-shift transmission

Assignee: Kanzaki Kokyukoki Manufacturing Co Ltd
•
Filing: 1987-11-27
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Granted: 1988-10-25
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Expires: 2007-11-27
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Abstract

Abstract In a transmission comprising a plurality of freely rotatable gears (11F 1 -11F 6 ) on a transmission shaft (10), each of shift keys (13) slidably disposed within the shaft is connected pivotally to a shift collar (14) using a pin (15). The collar includes a diameter-reduced cylindrical extension (18) having therein slots (18a) through which base end projections (17) of the keys extend radially outwardly of the shaft. The shift keys are biased to pivot for a selective gear-coupling operation by coned disk springs (19) which are disposed on the cylindrical extension and between the collar and the projections. The disk springs (19) which do not require an enlargement of the outer diameter of shift collar (14) effect a large biasing force upon shift keys (13) for the gear-coupling operation. Further, the disk springs mounted on the cylindrical extension (18) do not cause, when the collar is shifted, a rubbing engagement with the shaft (10) so that a lightness of the shifting operation is assured.

Inventors

  • 👤 Koji Irikura
  • 👤 Hideaki Okada

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 14:54
CPC Classifications
F; F16; F16H; F16H3/00; F16H3/02; F16H3/08; F16H3/083; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19219; Y10T74/19377; Y10T74/19414; Y10T74/19419; Y10T74/19442; Y10T74/19451; Y10T74/1946

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 296 words
A key-shift transmission comprising: a transmission shaft having at its outer surface elongated axial grooves; a plurality of axially spaced speed-change gears rotatably mounted on said transmission shaft; shift keys slidably disposed within said axial grooves and having at free ends thereof gear-engaging lugs for coupling said speed-change gears one at a time to said transmission shaft; and a shift collar slidably mounted on said transmission shaft for shifting said shift keys axially of said shaft, each of said shift keys being connected at a base end portion thereof to said shift collar by a pin rotatably along a direction such that said gear-engaging lug thereof is moved radially of said transmission shaft, characterized in: that each of said shift keys (13) is formed integrally at said base end portion thereof with an axially spaced shorter first projection (16) and taller second projection (17) which extend radially outwardly of said transmission shaft (10), said first projection being received in a slot (14a) formed to said shift collar (14) and being connected to said collar by said pin (15), and said second projection being faced to said shift collar from a direction opposite to said gear-engaging lug (13a); and that said shift collar (14) is formed integrally with a diameter-reduced cylindrical portion (18) extending axially towards said second projection (17) and including a slot (18a) which is continuous with said slot (14a) so as to permit said base end portion of said each shift key (13) to pass therethrough, coned disk spring means (19) being disposed on said cylindrical portion and between said shift collar and said second projection so as to bias said shift key (13) to rotate towards a direction such that said gear-engaging lug (13a) is projected radially outwardly of said transmission shaft (10).
Claim 2
Dependent Claim 296 words
A key-shift transmission comprising: a transmission shaft having at its outer surface elongated axial grooves; a plurality of axially spaced speed-change gears rotatably mounted on said transmission shaft; shift keys slidably disposed within said axial grooves and having at free ends thereof gear-engaging lugs for coupling said speed-change gears one at a time to said transmission shaft; and a shift collar slidably mounted on said transmission shaft for shifting said shift keys axially of said shaft, each of said shift keys being connected at a base end portion thereof to said shift collar by a pin rotatably along a direction such that said gear-engaging lug thereof is moved radially of said transmission shaft, characterized in: that each of said shift keys (13) is formed integrally at said base end portion thereof with an axially spaced shorter first projection (16) and taller second projection (17) which extend radially outwardly of said transmission shaft (10), said first projection being received in a slot (14a) formed to said shift collar (14) and being connected to said collar by said pin (15), and said second projection being faced to said shift collar from a direction opposite to said gear-engaging lug (13a); and that said shift collar (14) is formed integrally with a diameter-reduced cylindrical portion (18) extending axially towards said second projection (17) and including a slot (18a) which is continuous with said slot (14a) so as to permit said base end portion of said each shift key (13) to pass therethrough, coned disk spring means (19) being disposed on said cylindrical portion and between said shift collar and said second projection so as to bias said shift key (13) to rotate towards a direction such that said gear-engaging lug (13a) is projected radially outwardly of said transmission shaft (10).
Claim 3
Dependent Claim 37 words
A key-shift transmission as claimed in claim 1, wherein said shift keys (13) are disposed within said elongated axial grooves (12) in a fashion such that said keys are kept apart from bottom surfaces of said grooves.
Claim 4
Dependent Claim 58 words
A key-shift transmission as claimed in claim 1, wherein said second projection (17) extends radially outwardly of said transmission shaft (10) to a radial position substantially equal to that of the outer circumference of said shift collar (14), said disk spring means (19) being received by respective outer end portions of said shift collar and said second projection.
Claim 5
Dependent Claim 35 words
A key-shift transmission as claimed in claim 3, wherein the outer end portion of said second projection (17) includes a protrusion (17a) directed towards said shift collar (14) for receiving said disk spring means (19).
Claim 6
Dependent Claim 60 words
A key-shift transmission as claimed in claim 3, wherein the outer end portion of said second projection (17) includes a protrusion (17a) directed towards said shift collar (14), said disk spring means (19) being received by said protrusion through a ring (20) which is disposed on said cylindrical portion (18) and between said disk spring means and said second projection.

References Cited (Backward Citations)

FR376640A Cited
GB191021262A Cited
US2395433A Cited
US3028763A Cited
JPS6065453A Cited
JPS61135047A Cited
US4702120A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-10-25 1992-04-25 1992-10-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-10-25 1996-04-25 1996-10-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-10-25 2000-04-25 2000-10-25 $7700.00 Window Closed / Lapsed

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