Material conveying equipment with control for paving materials using ultrasonic waves
First Claim
1. In a paving material conveying equipment having a first conveying device for distributing a paving material in a first direction on a surface to be paved, a second conveying device for conveying said paving material in a second direction to said first conveying device, sensing means for sensing the height of said paving material distributed by said first conveying device onto said surface to be paved, at a given position, for producing a control signal, and means responsive to said control signal for controlling the quantity of paving material distributed by said first conveying device to said given position for maintaining said height substantially constant;
- the improvement wherein said sensing means comprises non-contacting sensing means fixedly mounted on said equipment spaced from said paving material at a predetermined height above said surface to be paved for producing said control signal, whereby said control signal is a function of the distance between said non-contacting sensing means and an upper surface of said paving material at said given position.
3 Assignments
0 Petitions
Accused Products
Abstract
A sensing arrangement for sensing the level of a bulk material, such as the paving material fed by a paving machine, comprises an ultrasonic transducer spaced from the paving material for controlling the feed of material.
70 Citations
20 Claims
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1. In a paving material conveying equipment having a first conveying device for distributing a paving material in a first direction on a surface to be paved, a second conveying device for conveying said paving material in a second direction to said first conveying device, sensing means for sensing the height of said paving material distributed by said first conveying device onto said surface to be paved, at a given position, for producing a control signal, and means responsive to said control signal for controlling the quantity of paving material distributed by said first conveying device to said given position for maintaining said height substantially constant;
- the improvement wherein said sensing means comprises non-contacting sensing means fixedly mounted on said equipment spaced from said paving material at a predetermined height above said surface to be paved for producing said control signal, whereby said control signal is a function of the distance between said non-contacting sensing means and an upper surface of said paving material at said given position.
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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11. In a road paving equipment movable along a first surface on which paving material is to be deposited and compacted, and comprising an auger for distributing paving material in a first direction transverse of the direction of movement of the equipment, a conveying device for conveying said paving material to said auger in a direction opposite said direction of movement, a screed mounted rearwardly of said auger, sensing means mounted on said equipment for producing a control signal that is a function of the height of said paving material at a given position adjacent said auger, and means responsive to said control signal for controlling the distribution of said paving material to said given position for maintaining said height substantially constant;
- the improvement wherein said sensing means comprises non-contacting sensing means fixedly mounted on said equipment spaced from said paving material at said given position for producing said control signal, whereby said control signal is a function of the distance between said non-contacting sensing means and an upper surface of said paving material at said given position.
- View Dependent Claims (12, 13, 14)
- 15. A control circuit for producing a control signal in response to the output of an ultrasonic transducer wherein the transducer is responsive to an input signal for transmitting an ultrasonic pulse and is responsive to an ultrasonic echo for outputting an echo signal, said control circuit comprising a timing circuit having a first output for periodically controlling said transducer to transmit ultrasonic pulses at a first predetermined time, a ramp signal generation circuit for generating a ramp signal, an integration circuit for producing said control signal, a first gate for passing the instantaneous amplitude of said ramp signal to said integration circuit, and means responsive to said echo signal for energizing said first gate circuit to pass the amplitude of said ramp signal to said integration circuit, said timing circuit further comprising means initiating the generation of said ramp signal at a second predetermined time following said first predetermined time, means stopping the generation of said ramp signal at a third predetermined time following said second predetermined time, and means for suppressing said ramp signal at a fourth predetermined time following said second predetermined time.
Specification