US 4,657,126 A · Two-speed clutch

Abstract

A two-speed clutch is shown according to the preferred embodiment of the teachings of the present invention for the selective rotational relation of an input shaft with a first or second sheeve unit having different diameters. The first sheeve unit is rotatably mounted to the input shaft. The second sheeve unit is mounted to a housing in turn rotatably mounted to the input shaft. The clutch includes a friction disc which is located between and frictionally interrelates with the first sheeve unit or the housing. The housing includes a single, reciprocally mounted piston for moving the friction disc. Utilizing a two-speed clutch of the present invention eliminates the requirement of two separate and complete drive units as in prior techniques. Furthermore, since the housing performs multiple functions, i.e., rotatably mounts the second sheeve unit to the input, slidably mounts the piston, acts as the interface for the second sheeve unit with the friction disc, and other functions, the two-speed clutch of the present invention greatly reduces the number of parts and results in a simplicity of construction. Furthermore, the two-speed clutch of the present invention provides a relatively dust and other element free environment for the piston and splined interconnection of the interfacing friction disc with the input.

Two-speed clutch comprising, in combination:

a hub for nonrotatably receiving an input shaft;
a first output sheeve;
means for rotatably mounting the first output sheeve on the input hub;
a radially extending annular interface disc connected to the first output sheeve, with the annular interface disc including an interface surface;
a first housing portion including an annular body portion having a radial inner end and a radial outer end terminating in an axially extending annular flange, with the annular flange having a free end;
means located between the radial inner end of the first housing portion and the input hub for rotatably mounting the first housing portion on the input hub;
a radially extending, annular housing disc having a first radial face;
with the annular housing disc being secured to the free end of the annular flange of the first housing portion to form a housing;
an interface surface formed on the first face of the annular housing for rotation therewith;
an interface disc slidably mounted on the input hub for rotation therewith, with the interface disc of the input hub located between the interface surfaces of the first output sheeve and the annular housing disc, with the interface disc of the input hub including a first interface surface for rotatably relating with the interface surface of the first output sheeve and a second interface surface for rotatably relating with the interface surface of the annular housing disc;
a single, annular piston;
means for reciprocally mounting the piston in the housing;
means for rotatably mounting the piston with respect to the interface disc of the input hub and for reciprocally relating the piston to the interface disc of the input hub for axial movement therewith;
a fluid pressure cylinder formed by the housing and the piston;
means for introducing fluid pressure into the fluid pressure cylinder for moving the piston in a first axial direction;
means for biasing the piston in the opposite axial direction, with the biasing means comprising, in combination:
a plurality of springs extending axially between the annular housing disc and the piston wherein the biasing means moves the piston and the input interface disc in the first axial direction for rotatably relating the input hub with one of the interface surfaces of the first output sheeve and the annular housing disc and when fluid pressure is introduced into the fluid pressure cylinder, the piston and the input interface disc moves in the opposite axial direction for rotatably relating the input hub with the other of the interface surfaces of the first output sheeve and the annular housing disc;
wherein the radial inner end of the annular body portion of the first housing portion defines an axially extending bore having an axially outward end;
wherein the fluid pressure introducing means comprises, in combination:
a circular disc secured to the annular body portion of the first housing portion having a size and shape for covering the axially outward end of the annular body portion of the first housing portion, an axially extending, annular flange extending from the circular disc in a direction opposite from the annular body portion of the first housing portion, a fluid pressure rotary union connected to a source of fluid pressure received within the annular flange of the circular disc for defining a pressure cavity by and between the circular disc, the annular flange, and the rotary union, and passage means for communicating the fluid pressure from the pressure cavity to the fluid pressure cylinder;
wherein the annular housing disc has an axially extending aperture extending therethrough, wherein the piston includes at least a portion thereof having a shape and size for receipt in the aperture of the annular housing disc and with relatively close tolerances to form a restricted air passage therebetween for reducing passage of dust and other elements therethrough;
a rotary air seal provided between the input interface disc and the first output sheeve for preventing passage of dust and other elements therethrough;
and wherein the rotary air seal, the piston, the housing, the circular disc, and the close tolerances between the annular housing disc and the input interface disc define a restricted dust and other element environment for the clutch.

20 more elements

Two-speed clutch

Life of this patent

Two-speed clutch

Life of this patent

Abstract

Claims20