Device for forming tight radius curbs and gutters with a paving machine
A system and method to allow a paving machine to form tight radii in continuous extrusions such as curbs and gutters is disclosed. A shift cylinder is used with the steering mechanism of a typical paving machine to allow sharp radius turns. The steering cylinder is used to pivot the track of the paving machine about its leg and the steering cylinder is used to pivot the leg relative to the frame of the paving machine. A hydraulic circuit is operator activated to allow fluid flow through a flow divider to ensure each cylinder operates in concert.
1. A system for use in a curb forming machine to allow the machine to form curbs having a tight radius, the curb forming machine having a frame;
at least three leg assemblies for supporting the machine, each leg assembly having a leg and a track mounted to the leg;
a hopper carried by the frame, the hopper including an opening for receiving curb forming material;
a slipform in communication with the hopper for receiving the curb forming material from the hopper for forming a curb, the system comprising;
a positioning arrangement for positioning a leg assembly on a forward end of the machine, the leg assembly adapted to form a tight radius, the positioning arrangement including means to rotate the track about the leg; means to rotate the leg relative to the frame about a vertical axis; a hydraulic circuit; and means to activate the hydraulic circuit, the hydraulic circuit being in fluid communication with the means to rotate the track about the leg and the means to rotate the leg relative to the frame;
wherein the means to rotate the track about the leg is a steering cylinder and the means to rotate the leg relative to the frame is a shift cylinder;
wherein activation of the hydraulic circuit actuates the steering cylinder to rotate the track about the leg, and actuates the shift cylinder to rotate the leg relative to the frame;
wherein the shift cylinder comprises a cylinder end pivotally mounted to the frame and a rod end pivotally mounted to the leg assembly, such as to rotate the leg assembly relative to the frame to position the corresponding leg assembly to form tight radii; and
wherein the hydraulic circuit is in fluid communication with each cylinder, the circuit being operational between a first disengaged state in which the hydraulic fluid is directed independently to the steering cylinder and shift cylinder to rotate the track about the leg, and a second engaged state in which the hydraulic fluid is diverted through a flow divider for delivery to the steering cylinder and the shift cylinder respectively to rotate the corresponding track about the leg and the leg relative to the frame simultaneously to form tight radii.
2. The machine of claim 1 , wherein in the second engaged state, hydraulic fluid is directed evenly between the cylinders to ensure smooth operation.
3. The machine or claim 1 , wherein the positioning arrangement further comprises a locking pin for locking the position of the leg assembly with respect to the frame.
4. The machine of claim 1 , wherein the means to activate the hydraulic circuit comprises a switch located in a cab of the paving machine.
5. In a curb forming machine comprising a frame with at least three leg assemblies for supporting the machine, each leg assembly having a leg and a track mounted to the leg; a hopper carried by the frame, the hopper including an opening for receiving curb forming material; and a slipform in communication with the hopper for receiving the curb forming material from the hopper for forming a curb, a method of enabling a leg assembly to form a tight radius, the method comprising the step of:
providing a positioning arrangement for positioning a front leg assembly to form a tight radius, the positioning arrangement including means to rotate the track about the leg;
providing means to rotate the leg relative to the frame about a vertical axis;
providing a hydraulic circuit having means to activate the hydraulic circuit, the circuit being in fluid communication with the means to rotate the track about the leg and the means to rotate leg relative to the frame;
wherein the means to rotate the track about the leg is a steering cylinder and the means to rotate the leg relative to the frame is a shift cylinder;
wherein activation of the hydraulic circuit actuates the steering cylinder to rotate the track about the leg, and actuates the shift cylinder to rotate the leg relative to the frame;
wherein the shift cylinder comprises a cylinder end pivotally mounted to the frame and a rod end pivotally mounted to the leg assembly, such as to rotate the leg assembly relative to the frame to position the corresponding leg assembly to form tight radii; and
wherein the hydraulic circuit is in fluid communication with each cylinder, the circuit being operational between a first disengaged state in which the hydraulic fluid is directed independently to the steering cylinder and shift cylinder to rotate the track about the leg, and a second engaged state in which the hydraulic fluid is diverted through a flow divider to the steering cylinder and the shift cylinder to rotate the corresponding track about the leg and the leg relative to the frame simultaneously to form tight radii.
6. The method of claim 5 , further comprising the step of locking the position of the leg assembly with respect to the frame with a locking pin.
7. The method of claim 5 , wherein the hydraulic circuit is actuated by actuating a switch located in a cab of the paving machine.