Anti-jacknifing device for tractor-trailer trucks

Claim 2

An anti-jacknifing device for tractor-trailer trucks provided with a fifth wheel secured to the tractor and with a kingpin fixedly secured to the trailer, and having an engaged position in which said kingpin engages said fifth wheel to oscillate therein and a disengaged position in which said kingpin is separated from the fifth wheel, said anti-jacknifing device comprising braking means mounted on said fifth wheel, and substantially vertical skirt means defining an arcuate portion of constant radius and mounted on said trailer concentrically with said kingpin, said braking means including at least two brake pads arranged opposite to each other and defining an arcuate gap having substantially the same radius as said skirt means and being concentric with said fifth wheel, said skirt means being located in said arcuate gap in the engaged position of the kingpin, spring means to urge said brake pads away from the skirt means, and actuating means to simultaneously urge the brake pads away towards the respective opposite sides of the skirt means.

Claim 3

An anti-jacknifing device as defined in claim 1, wherein said fifth wheel is provided with two tapered arms extending in rearward direction and defining a generally Y-shaped kingpin slot, wherein a kingpin plate provided with a kingpin is attached to the under surface of said trailer, and wherein in the engaged position of the kingpin, said kingpin plate engages the upper surface of the fifth wheel, said kingpin being located at the innermost portion of said kingpin slot, and the uppermost surface of said braking means lying in substantially the same plane as said upper surface of the fifth wheel.

Claim 4

An anti-jacknifing device as defined in claim 2. wherein said braking means is located in the angular portion of said Y-shaped kingpin slot and includes supporting means to detachably connect said braking means to said fifth wheel, and wherein said arcuate skirt means is fixedly attached to said king-pin plate and has a larger radius than the radius of the fifth wheel.

Claim 5

An anti-jacknifing device as defined in claim 3, wherein said supporting means includes two sidewalls abutting the inner surfaces of said tapered arms and a stepped generally V-shaped caliper plate affixed to the upper edges of said sidewalls and defining an upper portion, a lower portion and an intermediate portion connecting both said upper and lower portions, said actuating means being secured to the under surface of said upper portion and said brake pads being located on the upper surface of said lower portion.

Claim 6

An anti-jacknifing device as defined in claim 4, wherein said sidewalls are each provided with at least two openings, and said supporting means further includes at least two brackets affixed to each under surface of said arms and provided with respective bores aligned with the corresponding openings in the sidewalls, at least two rods being received in said aligned bores and openings to support the braking means with relation to the fifth wheel.

Claim 7

An anti-jacknifing device as defined in claim 3, wherein said actuating means includes operating means to connect the main braking system of a truck with said braking means to actuate said brake pads, said operating means comprising a servomotor means detachably connected to the main braking system of a truck, a master cylinder having a piston mechanically connected to said servomotor means, and at least two secondary cylinders hydraulically operated, in parallel, by the piston of said master cylinder and mechanically connected to each one of said brake pads.

Claim 8

An anti-jacknifing device as defined in claim 6, wherein said braking means includes four brake pads arranged in groups of two on each side of said arcuate gap, each pad of one group being substantially opposite to a corresponding pad of the other group, and eight secondary cylinders connected in parallel to said master cylinder, each one of said brake pads being actuated by two of said secondary cylinders.

Claim 9

An anti-jacknifing device as defined in claim 6, wherein said servomotor means connected to the main braking system of the truck is pneumatically operated.

Claim 10

An anti-jacknifing device as defined in claim 6, wherein said servomotor means connected to the main braking system of the truck is hydraulically operated.

Claim 11

An anti-jacknifing device as defined in claim 10, wherein said servomotor means connected to the main braking system of the truck is electrically operated.

Claim 12

An anti-jacknifing device for tractor-trailers of the type wherein a trailer means is detachably connected with a tractor means by kingpin means for relative swinging movement about a vertical axis, said tractor means including wheel brake operating means including an element movable in one direction when wheel braking force is applied, said trailer means including a braking surface for frictional coaction with braking means on the tractor means to resist said relative swinging movement, said braking means including, a housing, hydraulically operable brake pad means mounted in said housing for movement between operative and inoperative positions, master cylinder means mounted in said housing, means to conTain a supply of hydraulic fluid in said housing in communication with said master cylinder and said brake pad means, whereby said brake pad means is moved between said operative and inoperative positions in response to reciprocating movement of the master cylinder, and means to detachably mount said housing on said tractor means and to detachably connect said master cylinder with said movable element of the wheel brake operating means.

Claim 13

An anti-jacknifing device for tractor-trailers of the type wherein a trailer means is detachably connected with a tractor means by kingpin means for relative swinging movement about a vertical axis, said tractor means including wheel brake operating means including an element movable in one direction when wheel braking force is applied, said trailer means including a braking surface for frictional coaction with braking means on the tractor means to resist said relative swinging movement, said braking means including, a housing, hydraulically operable brake pad means mounted in said housing for movement between operative and inoperative positions, master cylinder means mounted in said housing, means to conTain a supply of hydraulic fluid in said housing in communication with said master cylinder and said brake pad means, whereby said brake pad means is moved between said operative and inoperative positions in response to reciprocating movement of the master cylinder, and means to detachably mount said housing on said tractor means and to detachably connect said master cylinder with said movable element of the wheel brake operating means.

Claim 14

An anti-jacknfing device as defined in claim 11, wherein said brake pad means includes a pair of oppositely disposed reciprocating pistons movable toward and away from each other between said operative and inoperative positions.

Claim 15

An anti-jacknifing device as defined in claim 11, wherein said kingpin means includes fifth wheel means attached to said tractor means, said fifth wheel means being provided with a generally inwardly converging opening, said housing of the braking means being detachably mounted in said opening.

Claim 16

An anti-jacknifing device as defined in claim 11, wherein said means to contain a supply of hydraulic fluid includes a tank provided in said housing, and conduit means connecting said master cylinder, said brake pad means and said tank.