Vibratory machines

Claim 3

In a vibratory roller machine, a frame; a vibratory ground contactable roll journaled in said frame and being adapted to be placed against the surface of material to be compacted; a rotating out of balance weight journaled within said vibratory roll to apply thereto a vibratory exciting force of substantially constant amplitude and frequency for causing said vibratory roll to follow an elliptical path in moving in response to said exciting force; transducer means comprising two accelerometers responsive to acceleration of the vibratory roll on two mutually perpendicular axes perpendicular to and intersecting the axis of the vibratory roll, said transducer means being operable in accordance with vibration of said vibratory roll and being sensitive to a function of the instantaneous amplitude of the elliptical path of vibration of said roll due to vibration of said vibratory roll from a rest position; means for isolating from the output of said transducer means a first signal substantially directly proportional to the length of the major axis of the elliptical path followed by said vibratory roll in response to said exciting force; and means continuously receiving said first signal and being responsive thereto to transmit a second signal useful for control purposes at least one value of said first signal.

Claim 4

In a vibratory roller machine, a frame; a vibratory ground contactable roll journaled in said frame and being adapted to be placed against the surface of material to be compacted; a rotating out of balance weight journaled within said vibratory roll to apply thereto a vibratory exciting force of substantially constant amplitude and frequency for causing said vibratory roll to follow an elliptical path in moving in response to said exciting force; transducer means comprising two accelerometers responsive to acceleration of the vibratory roll on two mutually perpendicular axes perpendicular to and intersecting the axis of the vibratory roll, said transducer means being operable in accordance with vibration of said vibratory roll and being sensitive to a function of the instantaneous amplitude of the elliptical path of vibration of said roll due to vibration of said vibratory roll from a rest position; means for isolating from the output of said transducer means a first signal substantially directly proportional to the length of the major axis of the elliptical path followed by said vibratory roll in response to said exciting force; and means continuously receiving said first signal and being responsive thereto to transmit a second signal useful for control purposes at least one value of said first signal.

Claim 5

In a vibratory machine, a vibratory part adapted to be placed against thE surface of material to be compacted; a rotating out of balance weight journaled in said part to apply thereto a vibratory exciting force of substantially constant magnitude and frequency for causing said vibratory part to follow an elliptical path in moving in response to said exciting force; transducer means operable in accordance with vibration of said vibratory part and being sensitive to at least one characteristic of said vibration, said at least one characteristic being a function of the instantaneous displacement of said vibratory part due to vibration of said vibratory part from a rest position; means for isolating from the output of said transducer means a first signal substantially directly proportional to the length of the major axis of the elliptical path followed by said vibratory part in response to said exciting force; and means continuously receiving said first signal and being responsive thereto to transmit a second signal useful for control purposes at at least one value of said firs signal, the transducer means comprising a plurality of accelerometers mounted on the vibratory part and being responsive to acceleration of the vibratory part on different axes disposed relative to the range of axes on which the maximum instantaneous displacement of said vibratory part occurs, whereby at least one transducer will always be situated on the axis sufficiently close to the actual axis of the maximum instantaneous displacement for the instantaneous displacement on the axis of said at least one transducer to be substantially equal to the maximum instantaneous displacement, said isolating means comprising means for receiving the output signals of said transducers and for integrating them twice against time, and means operative to select the largest of said integrated signals to provide said first signal.

Claim 6

In a vibratory machine, a vibratory part adapted to be placed against thE surface of material to be compacted; a rotating out of balance weight journaled in said part to apply thereto a vibratory exciting force of substantially constant magnitude and frequency for causing said vibratory part to follow an elliptical path in moving in response to said exciting force; transducer means operable in accordance with vibration of said vibratory part and being sensitive to at least one characteristic of said vibration, said at least one characteristic being a function of the instantaneous displacement of said vibratory part due to vibration of said vibratory part from a rest position; means for isolating from the output of said transducer means a first signal substantially directly proportional to the length of the major axis of the elliptical path followed by said vibratory part in response to said exciting force; and means continuously receiving said first signal and being responsive thereto to transmit a second signal useful for control purposes at at least one value of said firs signal, the transducer means comprising a plurality of accelerometers mounted on the vibratory part and being responsive to acceleration of the vibratory part on different axes disposed relative to the range of axes on which the maximum instantaneous displacement of said vibratory part occurs, whereby at least one transducer will always be situated on the axis sufficiently close to the actual axis of the maximum instantaneous displacement for the instantaneous displacement on the axis of said at least one transducer to be substantially equal to the maximum instantaneous displacement, said isolating means comprising means for receiving the output signals of said transducers and for integrating them twice against time, and means operative to select the largest of said integrated signals to provide said first signal.

Claim 7

In a vibratory roller machine, a frame; a vibratory ground contactable roll journaled in said frame and being adapted to be placed against the surface of material to be compacted; a rotating out of balance weight journaled within said vibratory roll to apply thereto a vibratory exciting force of substantially constant magnitude and frequency for causing said vibratory roll to follow an elliptical path in moving in response to said exciting force; transducer means operable in accordance with vibration of said vibratory roll and being sensitive to a function of the instantaneous amplitude of the elliptical path of vibration of said roll due to vibration of said vibratory roll from a rest position; means for isolating from the output of said transducer means a first signal substantially directly proportional to the length of the major axis of the elliptical path followed by said vibratory roll in response to said exciting force; and means continuously receiving said first signal and being responsive thereto to transmit a second signal useful for control purposes at at least one value of said first signal, the transducer means comprising a plurality of accelerometers mounted on said roll and being responsive to acceleration of said roll on different axes disposed relative to the range of axes on which the maximum value of said first signal is generated, whereby at least one transducer will always be situated on an axis sufficiently close to the actual axis on which said maximum signal is generated for the displacement on the axis of that transducer to be substantially equal to the maximum instantaneous displacement, and wherein said isolation means comprises means for receiving the output signals of said transducers and for integrating them twice against time, and means operative to select the largest of said integrated signals to provide said first signal.

Claim 8

In a vibratory roller machine, a frame; a vibratory ground contactable roll journaled in said frame and being adapted to be placed against the surface of material to be compacted; a rotating out of balance weight journaled within said vibratory roll to apply thereto a vibratory exciting force of substantially constant magnitude and frequency for causing said vibratory roll to follow an elliptical path in moving in response to said exciting force; transducer means operable in accordance with vibration of said vibratory roll and being sensitive to a function of the instantaneous amplitude of the elliptical path of vibration of said roll due to vibration of said vibratory roll from a rest position; means for isolating from the output of said transducer means a first signal substantially directly proportional to the length of the major axis of the elliptical path followed by said vibratory roll in response to said exciting force; and means continuously receiving said first signal and being responsive thereto to transmit a second signal useful for control purposes at at least one value of said first signal, the transducer means comprising a plurality of accelerometers mounted on said roll and being responsive to acceleration of said roll on different axes disposed relative to the range of axes on which the maximum value of said first signal is generated, whereby at least one transducer will always be situated on an axis sufficiently close to the actual axis on which said maximum signal is generated for the displacement on the axis of that transducer to be substantially equal to the maximum instantaneous displacement, and wherein said isolation means comprises means for receiving the output signals of said transducers and for integrating them twice against time, and means operative to select the largest of said integrated signals to provide said first signal.

Claim 9

The vibratory machine of claim 4, wherein said accelerometers are mounted with their axes of response radial with respect to the axis of the roll.

Claim 10

The vibratory machine of claim 4, wherein said transducers are two in number, are mounted on the roll so as to respond on axes separated by approximately 25* and are symmetrically placed relative to the center of the range of axes assumed by the axis of the maximum instantaneous displacement of said roll.

Claim 11

The vibratory machine of claim 3, wherein the accelerometers are piezoelectric accelerometers, the output of each accelerometer being applied to an integrating channel comprising in succession a buffer amplifier, two AC coupled stages of integrating amplification, and a further buffer amplifier, the outputs of the integrating channels being applied to an OR gate biased to have a selecting and rectifying function, the output of the gate being smoothed and applied to a meter.

Claim 12

The vibratory machine of claim 4, including a signal lamp, and wherein said accelerometers are piezoelectric accelerometers, the output of each accelerometer being applied to an integrating channel comprising in succession a buffer amplifier, two AC coupled stages of integrating amplification, and a further buffer amplifier, the outputs of the integrating channels being applied to an OR gate biased to have a selecting and rectifying function, the output of the gate being smoothed and applied to a circuit adapted to switch on said signal lamp in response to a preset signal level.

Claim 13

The combination with a vibratory machine having a member vibrationally excited by a rotating out of balance weight and being adapted to be placed against the surface of material to be compacted, of a compaction indicator comprising a plurality of unidirectional accelerometers mounted on the vibrationally excited member on angularly spaced axes within the range of angles assumed by the major axis of the ellipse traced by said member in response to said vibrationary excitement; and a computing and display unit comprising a plurality of integrating channels each receiving the output from one of said accelerometers and each comprising two series connected AC coupled integrating circuits, means to detect the maximum value of the output of that channel producing the largest output of any of said channels, and means to smooth and measure said detected value.

Claim 14

The combination with a vibratory machine having a member vibrationally excited by a rotating out of balance weight and being adapted to be placed against the surface of material to be compacted, of a compaction indicator comprising a plurality of unidirectional accelerometers mounted on the vibrationally excited member on angularly spaced axes within the range of angles assumed by the major axis of the ellipse traced by said member in response to said vibrationary excitement; and a computing and display unit comprising a plurality of integrating channels each receiving the output from one of said accelerometers and each comprising two series connected AC coupled integrating circuits, means to detect the maximum value of the output of that channel producing the largest output of any of said channels, and means to smooth and measure said detected value.

Claim 15

The combination according to claim 9, wherein said means to smooth and measure the detected value comprises a meter.

Claim 16

The combination according to claim 9, wherein the means to smooth and measure the signal comprises a lamp and a circuit responsive to a preset signal level to illuminate said lamp, the preset signal level being variable against a calibrated scale.