Reversing switch actuator for fluid motor

Claim 2

A switch assembly for a fluid motor of the type having a component movable therein by fluid pressure, said assembly comprising a housing secured to said motor at one end thereof; a switch on said housing; switch actuating means in said housing including a switch actuating rod longitudinally movable in said housing and having one end portion engageable with said switch to actuate the latter and having a radially enlarged opposite end portion, a ball adjacent said radially enlarged portion also longitudinally movable in said housing, and spring means in said housing biasing said radially enlarged portion against said ball to position the latter in the path of movement of cam means on said component; said cam means, upon movement of said component to a predetermined position, being operative by engagement with said ball to longitudinally move said rod to switch actuating position; and means responsive to actuation of said switch to initiate movement of said component in a direction away from such predetermined position.

Claim 3

The switch assembly of claim 1 wherein said ball and said enlarged portion are exposed to fluid pressure but are pressure balanced; said rod being longitudinally slidably sealed in said housing and being of relatively small diameter as compared with the diameter of said ball and of said radially enlarged portion whereby said spring means needs only to overcome a relatively small force imposed on said rod by fluid pressure acting on the small effective area thereof.

Claim 4

The switch assembly of claim 1 wherein said radially enlarged portion has a plane end face engaged with said ball thus to accommodate eccentricity of said rod and ball without binding of said rod in said housing.

Claim 5

The switch assembly of claim 1 wherein a duplicate switch assembly is disposed at the other end of said motor and wherein said component has another cam means for engaging and moving the ball of said duplicate switch assembly for actuation of the switch thereof to initiate movement of said component in a direction away from an opposite predetermined position whereby said component is automatically reciprocated between such predetermined positions.

Claim 6

The switch assembly of claim 1 wherein the path of movement of said component is angularly related to the path of movement of said ball and rod, said ball having lateral sliding engagement with said radially enlarged portion thus to substantially eliminate transfer of side load from said ball to said rod.

Claim 7

The switch assembly of claim 5 wherein movement of said ball by engagement Of said cam means therewith tends to rotate said ball in a direction to further decrease tendency of transmission of side load to said rod.

Claim 8

The switch assembly of claim 1 wherein said last-named means comprises a solenoid operated valve which, upon actuation of said switch, conducts fluid pressure into said motor to move said component away from such predetermined position.

Claim 9

A switch assembly for the cylinder head of a fluid motor of the type having a piston movable by fluid pressure in the cylinder thereof toward and away from said cylinder head; said assembly comprising cam means on said piston movable into and out of a central axial bore in said cylinder head; said cylinder head having a radial bore intersecting said central bore; a switch secured to said cylinder head; switch actuating means in said radial bore including a switch actuating rod coaxial with said radial bore having a radially outer end portion engageable with said switch to actuate the latter and having a laterally enlarged radially inner end portion, a ball adjacent said enlarged portion, said spring means biasing said enlarged portion against said ball to position the latter with a radially inner portion thereof disposed in the path of movement of said cam means; said cam means being operative by engagement with said ball to radially outwardly move said ball and said rod thus to actuate said switch; and means responsive to actuation of said switch to direct fluid under pressure into said cylinder head to initiate movement of said piston away from said cylinder head.

Claim 10

A switch assembly for the cylinder head of a fluid motor of the type having a piston movable by fluid pressure in the cylinder thereof toward and away from said cylinder head; said assembly comprising cam means on said piston movable into and out of a central axial bore in said cylinder head; said cylinder head having a radial bore intersecting said central bore; a switch secured to said cylinder head; switch actuating means in said radial bore including a switch actuating rod coaxial with said radial bore having a radially outer end portion engageable with said switch to actuate the latter and having a laterally enlarged radially inner end portion, a ball adjacent said enlarged portion, said spring means biasing said enlarged portion against said ball to position the latter with a radially inner portion thereof disposed in the path of movement of said cam means; said cam means being operative by engagement with said ball to radially outwardly move said ball and said rod thus to actuate said switch; and means responsive to actuation of said switch to direct fluid under pressure into said cylinder head to initiate movement of said piston away from said cylinder head.

Claim 11

The switch assembly of claim 8 wherein said ball and said enlarged portion are exposed to fluid pressure in said cylinder head but are pressure balanced; said rod being radially slidably sealed in said cylinder head and being of relatively small diameter as compared with the diameter of said ball and of said enlarged portion whereby said spring means needs only to overcome a relatively small force imposed on said rod by fluid pressure acting on the small effective area thereof.

Claim 12

The switch assembly of claim 8 wherein a switch retainer is secured in the radially outer portion of said radial bore to provide means by which said switch is secured to said cylinder head and to provide a guide bore for radial movement of said rod.

Claim 13

The switch assembly of claim 10 wherein said radial bore adjacent its radially inner portion provides a guide bore for radial movement of said ball and a seat to determine the radially innermost position of said ball so as to be engaged by said cam means.

Claim 14

The switch assembly of claim 11 wherein said enlarged portion has a plane end face engaged with said ball thus to accommodate eccentricity of said ball and rod guide bores without binding of said rod in said retainer.