Patent EP0146224A1 successfully refreshed from Google Patents.
EP0146224A1
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Toothed belt drive
Assignee: Mitsuboshi Belting Ltd
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Filing: 1984-10-11
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Granted: —
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Expires: 2004-10-11
Abstract
Abstract A toothed belt drive system wherein either or both of the belt teeth (13) and pulley grooves (14) include, in cross section, elliptical arcuate portions coordinated with circularly arcuate portions in providing resistance to cracking, minimizing of tapping noise by engagement of the belt groove roots with the pulley teeth, smooth withdrawal of the belt from the pulley, and abrasion of the belt groove root portions. The tooth and pulley groove configurations may include rectilinear portions (15). Preferred angular relationship between the elliptical arc axes and dimensions of the different portions of the belt teeth and pulley groove configurations embodying the invention are disclosed.
Inventors
- 👤 Takahide Mizuno
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 07:19
CPC Classifications
F; F16; F16H; F16H7/00; F16H7/02; F16H7/023; F16G; F16G1/00; F16G1/28
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
232 words
Drive means comprising: a pulley having an annular belt-engagement means defined by an annular series of alternating grooves and teeth, each of the grooves being defined in cross section by a circular arc defining the root of the grooves and having opposite outer ends, a pair of straight lines extending one each outwardly from said opposite outer ends of the root arcs and having outer distal ends, and a pair of circular entrance arcs extending one each outwardly from said distal ends of the straight lines, the teeth between said grooves having tip surfaces, each tip surface being defined by a straight line interconnecting opposed ends of the circular entrance arcs of the grooves at the opposite sides of the tooth; and a drive belt having a series of alternating grooves and teeth at a constant pitch, each belt tooth being defined in cross section by: a tip surface defined by a pair of elliptical arcs meeting at the centerline of the tooth and defining outer ends, the long axes of the ellipses defining the elliptical arcs being at equal and opposite angles to the centerline of the tooth; and opposite flanks defined by outturned circular arcs extending one each from the outer ends of the elliptical arcs, backlash between said belt teeth and said pulley groove in static engagement increasing linearly from the belt tooth flank to the belt tip face.
Claim 2
Dependent Claim
232 words
Drive means comprising: a pulley having an annular belt-engagement means defined by an annular series of alternating grooves and teeth, each of the grooves being defined in cross section by a circular arc defining the root of the grooves and having opposite outer ends, a pair of straight lines extending one each outwardly from said opposite outer ends of the root arcs and having outer distal ends, and a pair of circular entrance arcs extending one each outwardly from said distal ends of the straight lines, the teeth between said grooves having tip surfaces, each tip surface being defined by a straight line interconnecting opposed ends of the circular entrance arcs of the grooves at the opposite sides of the tooth; and a drive belt having a series of alternating grooves and teeth at a constant pitch, each belt tooth being defined in cross section by: a tip surface defined by a pair of elliptical arcs meeting at the centerline of the tooth and defining outer ends, the long axes of the ellipses defining the elliptical arcs being at equal and opposite angles to the centerline of the tooth; and opposite flanks defined by outturned circular arcs extending one each from the outer ends of the elliptical arcs, backlash between said belt teeth and said pulley groove in static engagement increasing linearly from the belt tooth flank to the belt tip face.
Claim 3
Dependent Claim
26 words
A drive means according to claim 1, wherein the angle of the ellipses to said tooth centerline is in the range of approximately 35° to 45°.
Claim 4
Dependent Claim
24 words
A drive means according to claim 1 or 2, wherein the eccentricity of said ellipses is in the range of approximately 0.6 to 0.9.
Claim 5
Dependent Claim
32 words
A drive means according to claim 1, 2 or 3,wherein the portion of the belt tooth extending from said flanks comprises approximately 60% to 90% of the total height of the tooth.
Claim 6
Dependent Claim
33 words
A drive means according to any preceding claim, wherein each of said tooth flanks further includes a rectilinear portion between the outer end of the tip face arc and the circular flank arc.
Claim 7
Dependent Claim
212 words
Drive means comprising: a pulley having an annular belt-engagement means defined by an annular series of alternating grooves and teeth, each of the grooves being defined in cross-section by a pair of elliptical arcs meeting at the centerline of the groove, the major axes of the ellipses defining said elliptical arcs intersecting at an angle of approximately 70° to 90°, the eccentricity of said ellipses being approximately 0.6 to 0.9, and a pair of circular entrance arcs extending one each outwardly from said distal ends of the straight lines, the teeth between said grooves having tip surfaces, each tip surface being defined by a straight line interconnecting opposed ends of the circular entrance arcs of the grooves at the opposite sides of the tooth; and a drive belt having a series of alternating grooves and teeth at a constant pitch, each belt tooth being defined in cross-section by: a tip face defined by a pair of elliptical arcs meeting at the centerline of the tooth and defining outer ends; and opposite flanks defined by outturned circular arcs extending one each from the outer ends of the elliptical arcs, backlash between said belt teeth and said pulley groove in static engagement increasing linearly from the belt tooth flank to the belt tip face.
Claim 8
Dependent Claim
212 words
Drive means comprising: a pulley having an annular belt-engagement means defined by an annular series of alternating grooves and teeth, each of the grooves being defined in cross-section by a pair of elliptical arcs meeting at the centerline of the groove, the major axes of the ellipses defining said elliptical arcs intersecting at an angle of approximately 70° to 90°, the eccentricity of said ellipses being approximately 0.6 to 0.9, and a pair of circular entrance arcs extending one each outwardly from said distal ends of the straight lines, the teeth between said grooves having tip surfaces, each tip surface being defined by a straight line interconnecting opposed ends of the circular entrance arcs of the grooves at the opposite sides of the tooth; and a drive belt having a series of alternating grooves and teeth at a constant pitch, each belt tooth being defined in cross-section by: a tip face defined by a pair of elliptical arcs meeting at the centerline of the tooth and defining outer ends; and opposite flanks defined by outturned circular arcs extending one each from the outer ends of the elliptical arcs, backlash between said belt teeth and said pulley groove in static engagement increasing linearly from the belt tooth flank to the belt tip face.
Claim 9
Dependent Claim
48 words
A drive means according to claim 6, wherein the gradient of the tangential line at each point on a sidewall of said pulley groove is in the range of approximately 80° to 90° at the connecting point of the circular arc and ellipses of said pulley tooth face.
Claim 10
Dependent Claim
43 words
A drive means according to claim 6 or 7, wherein the angle of intersection of the major axes of the ellipses of said belt teeth is smaller than the angle of intersection of the major axes of the ellipses of said pulley groove.
Claim 11
Dependent Claim
36 words
A drive means according to any of claims 6 to 8, wherein the portion of said belt teeth defined by said circular arcs and elliptical arcs comprises approximately 60%-90% of the height of the belt teeth.
Claim 12
Dependent Claim
40 words
A drive means according to any of claims 6 to 9, wherein the backlash between said belt teeth and said pulley grooves in the static engagement increases from the belt tooth flank and decreases toward the belt tooth tip face.
Claim 13
Dependent Claim
17 words
A drive means according to any preceding claim, wherein backlash is in the range of approximately 15"-10°.
Claim 14
Dependent Claim
25 words
A drive means according to any preceding claim, wherein the height of said belt tooth is substantially equal to the height of said pulley groove.
Claim 15
Dependent Claim
45 words
A drive means according to any of claims 1 to 11, wherein the height of said belt tooth is in the range of approximately 2%-15% greater than the height of said pulley groove, whereby the belt comes in close contact with the pulley groove surface.
References Cited (Backward Citations)
US3002396A
Cited
GB1294103A
Cited
US3856051A
Cited
US4233852A
Cited
GB2092704A
Cited
GB2109503A
Cited
GB2116287A
Cited
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