Centrifugal clutch

Claim 2

A centrifugal clutch comprising: a drum; a drive hub coaxially rotatably mounted in said drum; a spider affixed to said hub and having a plurality of radially outwardly extending arms; at least three clutch shoes of arcuate configuration mounted on said spider to be arranged in a circumferential series of equally circularly spaced apart shoes around said hub; said arms of said spider comprising a first series of equally circularly spaced apart arms arranged to slidably bear against mid-portions of one axial end of said shoes and a second set of equally circularly spaced apart arms in the same plane as said first arms and having outer end portions of channel-shaped configuration each disposed between adjacent ends of a pair of said shoes to define a pair of seats for each of said shoes; each of said channel-shaped portions terminating in a pair of oppositely circularly extending flanges disposed in a plane parallel to the plane of said first arms and slidably engaging the other axial ends of said shoes; said arms of said spider holding said shoes against axial displacement relative to said hub and slidably supporting said shoes for movement radially into and out of contact with said drum, said pair of seats for each of said shoes supporting said shoes in a radially retracted position with radial clearance between outer edges of said shoes and said drum, said seats being adapted to transmit torque from said hub to said shoes.

Claim 3

A clutch as in claim 1 in which: each of said shoes, in radially retracted position, has opposite ends on a clockwise facing and a counterclockwise facing pair of said seats, said clockwise and counterclockwise facing seats being oriented substantially radially in directions to include an angle having its apex offset from the axis of rotation of said hub, each of said clockwise and counterclockwise facing seats also defining an acute angle with respect to a tangent to said drum at the intersection of the projected plane of each said seat with said drum to wedgingly receive an end of said shoe.

Claim 4

A clutch as in claim 1 that includes: a plurality of springs each of which is interconnected at opposite ends to a radially inner edge of an adjacent pair of said shoes, said springs defining an aperture through which said hub is received, said springs normally biasing said shoes into radially retracted positions on said seats.

Claim 5

A clutch as in claim 1 in which: said drum includes a radially disposed web portion formed with a plurality of vent holes through which cooling air may be drawn upon rotation of said spider, said circularly spaced apart arms of said spider being effective to displace air within said drum.

Claim 6

A centrifugal clutch comprising: a clutch drum; a drive hub coaxially rotatably mounted in said drum; a spider formed of a rigid sheet material that is coaxially rigidly affixed to said hub to be rotatably positioned within said drum; said spider being shaped and adapted to define at least three pairs of opposed seats for opposite ends of clutch shoes to be mounted in said spider; at least three circularly arranged clutch shoes, each of said shoes comprising an arcuate segment and each being mounted in said spider with opposite ends of the shoes in slidable engagement with the corresponding pair of said opposed seats; a plurality of spring means each of which is connected at opposite ends to an adjacent pair of said shoes at radially inner edges of said shoes; said spring means normally biasing said shoes into radially retracted positions in which each shoe has opposite ends abutting said pair of seats with radial clearance between the radially outer edge of said shoe and said drum; said spring means being adapted to yield to the centrifugal force of said shoes, upon rotation of said hub, for permitting radial expansion of said shoes into frictional contact with said drum; said spider including a plurality of radially extending arms alternate ones of which slidably bear against one axial end of said shoes and the others of which slidably bear against the other axial ends of said shoes, alternate ones of said arms having channel-shaped outer portions disposed between adjacent ends of a pair of said shoes, said seats comprising axially extending portions of said channel-shaped portions.

Claim 7

A centrifugal clutch comprising: a clutch drum; a drive hub coaxially rotatably mounted in said drum; a spider formed of a rigid sheet material that is coaxially rigidly affixed to said hub to be rotatably positioned within said drum; said spider being shaped and adapted to define at least three pairs of opposed seats for opposite ends of clutch shoes to be mounted in said spider; at least three circularly arranged clutch shoes, each of said shoes comprising an arcuate segment and each being mounted in said spider with opposite ends of the shoes in slidable engagement with the corresponding pair of said opposed seats; a plurality of spring means each of which is connected at opposite ends to an adjacent pair of said shoes at radially inner edges of said shoes; said spring means normally biasing said shoes into radially retracted positions in which each shoe has opposite ends abutting said pair of seats with radial clearance between the radially outer edge of said shoe and said drum; said spring means being adapted to yield to the centrifugal force of said shoes, upon rotation of said hub, for permitting radial expansion of said shoes into frictional contact with said drum; said spider including a plurality of radially extending arms alternate ones of which slidably bear against one axial end of said shoes and the others of which slidably bear against the other axial ends of said shoes, alternate ones of said arms having channel-shaped outer portions disposed between adjacent ends of a pair of said shoes, said seats comprising axially extending portions of said channel-shaped portions.

Claim 8

In a centrifugal clutch the combination comprising: a cylindrical drum having hub means adapted for connection to a load; a drive hub coaxially rotatably mounted within said drum in coaxial alignment with said hub means of said drum; a spider coaxially mounted on said drive hub and formed with first and second sets of arms in circumferentially spaced apart relationship; a plurality of arcuately shaped clutch shoes, each having slidable contact with one of said first sets of arms and with terminal end portions of a pair of said second sets of arms; a plurality of springs interconnected to said plurality of clutch shoes to bias said shoes radially inwardly of said spider; each of said second arms being interposed between adjacent ends of a pair of said shoes and having its outer terminal end portion defining a pair of oppositely circularly facing seats against which said adjacent shoe ends are biased by said springs, each of said outer terminal end portions also including surface areas in parallel offset relationship to said first set of arms in order to slidably support said shoes therebetween.

Claim 9

In a centrifugal clutch the combination comprising: a cylindrical drum having hub means adapted for connection to a load; a drive hub coaxially rotatably mounted within said drum in coaxial alignment with said hub means of said drum; a spider coaxially mounted on said drive hub and formed with first and second sets of arms in circumferentially spaced apart relationship; a plurality of arcuately shaped clutch shoes, each having slidable contact with one of said first sets of arms and with terminal end portions of a pair of said second sets of arms; a plurality of springs interconnected to said plurality of clutch shoes to bias said shoes radially inwardly of said spider; each of said second arms being interposed between adjacent ends of a pair of said shoes and having its outer terminal end portion defining a pair of oppositely circularly facing seats against which said adjacent shoe ends are biased by said springs, each of said outer terminal end portions also including surface areas in parallel offset relationship to said first set of arms in order to slidably support said shoes therebetween.

Claim 10

A centrifugal clutch as in claim 6 in which said first set of arms is arranged to slidably bear against mid-portions of one axial end of said shoes and said second set of arms extend radially outwardly in the same plane as said first arms and have outer end portions of channel-shaped configuration disposed between adjacent ends of a pair of said shoes to define said pair of seats, each of said channel-shaped portions terminating in a pair of oppositely circularly extending flanges disposed in a plane parallel to the plane oF said first arms and slidably engaging the other axial ends of said shoes.

Claim 11

A centrifugal clutch as in claim 6 in which each of said shoes is formed with opposite end faces having integrally formed projections defining shoulders with said end faces; said second set of arms having radially outer terminal end portions laterally offset from the plane of radially outer terminal end portions of said first arms by a distance less than the axial dimension of said shoes; said outer ends of said second arms having one side slidably engaging sides of an adjacent pair of said projections oppositely to said first arms, and having opposite edges defining a pair of said seats slidably abutting adjacent end faces of an adjacent pair of said shoes.