APPARATUS FOR FORMING A CONTINUOUS CURB STRUCTURE

• US 3,749,504 A
• Filed: 04/30/1971
• Issued: 07/31/1973
• Est. Priority Date: 04/30/1971
• Status: Expired due to Term

• Current Assignee: Roy W. Smith
• Original Assignee: Roy W. Smith
• Inventors: Smith, Roy W.
• Primary Examiner(s): Byers, Jr., Nile C.
• Application Number:
  US05/138,882
• Time in Patent Office: 823 Days
• Field of Search: 94/46,46AC
• US Class Current: 404/84.2
• CPC Class Codes: B62D 55/116 Attitude or position control of chassis by action on suspension, e.g. to compensate for a slope
• CPC Class Codes: E01C 19/008 by reference lines placed along the road, e.g. wires co-operating with feeler elements E01C19/006 takes precedence
• CPC Class Codes: E01C 19/4893 Apparatus designed for railless operation

Abstract

An apparatus for forming a continuous strip of pavement such as a curb, gutter or the like along a prepared ground surface. The apparatus is self-propelled and includes a mold adapted to continuously extrude a preformed paving strip as the apparatus moves along the ground. Provision is made for automatically adjusting the elevation of the mold according to an externally positioned control line, and for maintaining the opposite sides of the mold substantially level with respect to each other. Provision is also made for automatically controlling the direction of movement of the apparatus in accordance with the external control line.

Claims

1. A self-propelled apparatus for forming a continuous strip of paving material such as a curb, gutter, or the like along a prepared ground surface having an external control line, said apparatus comprising a generally rectangular frame defining a front end, a rear end, a near side, a far side, and four corners, a supporting wheel member positioned at each of the four corners of the frame, means for adjustably interconnecting the supporting wheel members and frame such that each of the wheel members may be selectively and independently raised or lowered with respect to the frame, power means carried by said frame for rotating at least two wheel members to propel the apparatus along the ground surface, mold means carried centrally within said frame for receiving the paving material and forming the same into a continuous strip as the apparatus moves along the ground surface, elevation sensor means including a first control line follower carried by the near side of said frame adjacent one near side wheel member for generating an output signal proportional to a displacement of that portion of the frame and mold means adjacent said one near side wheel member above or below a preselected elevation represented by the external control line, and a second control line follower carried by the near side of said frame adjacent the other near side wheel member for generating an output signal proportional to a displacement of that portion of the frame and mold means adjacent said other near side wheel member above or below a preselected elevation represented by the external control line, first elevation control means carried by said frame and responsive to the output signal from said first control line follower for selectively actuating said interconnecting means associated with said one near side wheel member to selectively raise or lower such wheel and thereby maintain the elevation of that portion of the frame and mold means adjacent said one near side wheel member at a preselected elevation in relation to the elevation of the control line, second elevation control means carried by said frame and responsive to the output signal from said second control line follower for selectively actuating said interconnecting means associated with said other near side wheel member to selectively raise or lower such wheel and thereby maintain the elevation of that portion of the frame and mold means adjacent said other near side wheel member at a preselected elevation in relation to the elevation of the control line, level sensor means including a first level sensor carried by the frame adjacent said one near side wheel member for generating an output signal proportional to a displacement of the far side of the apparatus from a level condition with respect to the near side and a second level sensor carried by the frame adjacent said other near side wheel member for generating an output signal proportional to the displacement of the far side of the apparatus from a level condition with respect to the near side, first level control means carried by said frame and responsive to the output signal from said first level sensor for selectiVely actuating said interconnecting means associated with the far side wheel member opposite said one near side wheel member to raise or lower such far side wheel member to re-establish a level condition between the two sides, and second level control means carried by said frame and responsive to the output signal from said second level sensor for selectively actuating said interconnecting means associated with the far side wheel member opposite said other near side wheel member to raise or lower such far side wheel member to re-establish a level condition between the two sides, whereby said first and second level sensors act independently from each other to provide accurate control of the elevation of the far side of the apparatus with respect to that of the near side.

2. The apparatus as defined in claim 1 wherein said means for adjustably interconnecting each of the wheel members and frame includes a vertically directed externally threaded stud rotatably carried by one of either the wheel member or frame, and an internally threaded member engaging said stud and fixedly carried by the other of either the wheel member or frame, such that rotation of said stud vertically translates the wheel in relation to said frame.

3. The apparatus as defined in claim 2 wherein each of said first and second control line followers comprises a horizontally directed arm adapted to contact the control line and having a preselected neutral position, and means for generating an electrical signal indicative of the direction of displacement of the arm from its neutral position and which is also proportional to the extent of such displacement.

4. The apparatus as defined in claim 3 wherein each of said first and second level sensors comprises a dampened pendulum adapted to provide a gravity vertical reference defining a neutral position relative to said frame, and means for generating an electrical signal indicative of the direction of displacement of the pendulum from said neutral position and which is proportional to the extent of such displacement.

5. The apparatus as defined in claim 4 wherein each of said first and second elevation control means and each of said first and second level control means includes a reversible hydraulic motor operatively connected to the associated stud and having separate forward and reverse ports.

6. The apparatus as defined in claim 5 further comprising first hydraulic pump means carried by said frame for selectively supplying pressurized fluid to the motor ports of said first elevation control means and said first level control means, said first hydraulic pump means comprising a first hydraulic pump, a first flow control valve positioned between said first hydraulic pump and the motor ports of said first elevation control means, and a second flow control valve positioned between said first hydraulic pump and the motor ports of said first level control means, each of said first and second valves including means for selectively directing the pressurized fluid through one of the motor ports at a rate proportional to the signal from the associated sensor means.

7. The apparatus as defined in claim 6 further comprising second hydraulic pump means carried by said frame for selectively supplying pressurized fluid to the motor ports of said second elevation control means and said second level control means, said second hydraulic pump means comprising a second hydraulic pump, a third flow control valve positioned between said second hydraulic pump and the motor ports of said second elevation control means, and a fourth flow control valve positioned between said second hydraulic pump and the motor ports of said second level control means, each of said third and fourth valves including means for selectively directing the pressurized fluid through one of the motor ports at a rate proportional to the signal from the associated sensor means.

8. The apparatus as defined in claim 4 wherein each of said first and second level sensors further compriSes manually controlled adjustment means for varying the neutral position of said pendulum to thereby permit the apparatus to maintain a preselected non-level condition during movement along the ground surface.

9. The apparatus as defined in claim 1 further including direction sensor means carried by said frame for generating an output signal coordinated to a deviation in the direction of movement of the apparatus from a predetermined direction corresponding to the direction of the external control line, and direction control means responsive to the output signal from said direction sensor means for selectively changing the direction of one pair of end wheel members to cause the apparatus to turn and re-establish the predetermined direction.

10. The apparatus as defined in claim 9 wherein said direction sensor means comprises a control line follower having a vertically directed arm adapted to contact the control line and having a preselected neutral position, and means for generating an electrical signal indicative of the direction of displacement of the arm from its neutral position and which is proportional to the extent of such displacement.

11. The apparatus as defined in claim 10 wherein said direction control means comprises means mounting the front end pair of wheel members for rotation about a pair of vertical axes with one of said axes extending upwardly from each wheel member, a tie rod operatively connecting said front end pair of wheel members to provide concurrent rotation of the wheel members about said axes, and steering hydraulic means for rotating said wheel members about their respective axes.

12. The apparatus as defined in claim 11 wherein said steering hydraulic means comprises a hydraulic cylinder carried by said frame and having separate forward and reverse ports, a piston carried in said cylinder and operatively connected to said wheel member mounting means, and hydraulic pump means for supplying pressurized hydraulic fluid to said cylinder ports and including a hydraulic pump and a flow control valve positioned between said hydraulic pump and said hydraulic cylinder, said flow control valve including means for selectively directing the pressurized fluid through one of said cylinder ports at a rate proportional to the signal from said direction sensor means.

13. The apparatus as defined in claim 1 wherein said power means includes a reversible hydraulic motor operatively connected to each wheel member, each of said motors including separate forward and reverse ports, and hydraulic pump means for concurrently supplying pressurized hydraulic fluid to either the forward or reverse ports of all of said motors and including a hydraulic pump and a manually operated flow control valve interposed between said hydraulic pump and motors.

14. The apparatus as defined in claim 1 wherein said mold means comprises an upper hopper portion adapted to receive the paving material, and a lower mold portion having an open bottom and open rear end.

15. The apparatus as defined in claim 14 wherein said mold means further comprises vibrating means for compacting and densifying the paving material received therein.