초록 ▼

A slack adjuster for axially moved push rods is provided. An axially extending rotating actuating shaft turns a helical, driving cam member that in turn axially displaces a non-rotating driven cam member. The driving and driven helical cam members are located in a housing with the actuating shaft ex

A slack adjuster for axially moved push rods is provided. An axially extending rotating actuating shaft turns a helical, driving cam member that in turn axially displaces a non-rotating driven cam member. The driving and driven helical cam members are located in a housing with the actuating shaft extending out of one end thereof and a threaded push rod extending out of the other end of the housing. A helical return spring is positioned between the driven cam and the inner wall of the housing to bias the cam members together. The push rod is held against rotation internally of the housing by a flange whose periphery is frictionally engaged by the return spring. A nut is threaded onto the rod and engaged by the driven cam member to transmit axial force to the push rod; and relative extension of the push rod from the cam members is accomplished by a one way spring brake acting on the nut and a disc clutch drive between the driving cam and nut. Lost motion is provided to prevent rotation of the nut on the rod during normal push rod clearance, and rotation of the nut on the push rod occurs when excessive push rod clearance occurs.

대표청구항 ▼

In a mechanically-actuated disc brake, including a rotor, rotatable about an axis, having a friction surface thereon, friction element means for frictionally engaging said rotor friction surface, a drive assembly including a rotatable helical cam member and an actuating member coaxially positioned w

In a mechanically-actuated disc brake, including a rotor, rotatable about an axis, having a friction surface thereon, friction element means for frictionally engaging said rotor friction surface, a drive assembly including a rotatable helical cam member and an actuating member coaxially positioned within, and rotationally interlocked with, said rotatable cam member, an annular nonrotatable cam member in communication with said drive assembly, whereby upon rotation of said drive assembly, said nonrotatable cam member axially translates in a forward brake-applying direction, a push rod communicating with said friction element means, said push rod coaxially positioned within, and circumscribed by, said rotatable and nonrotatable cam members, an annular nut circumscribing and threadably engaging said push rod, said annular nut having a shank portion, coaxially positioned within said rotatable and nonrotatable cam members, and a radially-projecting flange communicating with said nonrotatable cam member, whereby said nonrotatable cam member urges the combination of said annular nut and push rod in said forward brake-applying direction in response to rotation of said drive assembly, thereby urging said friction element means into engagement with said rotor friction surface, means for biasing the combination of said annular nut and push rod in a rearward brake-releasing direction upon counter-rotation of said drive assembly, the improvement comprising adjusting means for rotating the annular nut relative to said push rod, thereby forwardly advancing said push rod with respect to said annular nut, said adjusting means including plate clutch means circumscribing, and projecting radially from, said annular nut and driven by said drive assembly, lost motion means, whereby said push rod is forwardly advanced with respect to said annular nut after a predetermined rotation of said drive assembly, and one-way brake means for frictionally resisting rearward retraction of said push rod with respect to said annular nut.