Vibrating Plate with Individually Adjustable Vibration Generators

Abstract

A vibrating plate comprises an upper mass with a drive, a lower mass with a soil contact plate ( 12 ), and a vibration generator device, which belongs to the lower mass and which acts upon the soil contact plate ( 12 ). The vibration generator device comprises at least two individual exciters ( 13 ) each having an unbalanced shaft ( 2 ). The individual exciters ( 13 ) can be individually controlled with regard to the rotational speed and/or phase position of the respectively assigned unbalanced shaft ( 2 ). A mechanical coupling of the unbalanced shafts ( 2 ) is thus unnecessary. The unbalanced shaft ( 2 ) of an individual exciter ( 3 ) can be rotationally driven by a hydraulic motor ( 4 ). The position of the unbalanced shaft ( 2 ) is determined in at least one position by a position indicator ( 7 ).

1 . A vibrating plate for soil compaction, comprising:
 an upper mass comprising a drive;   a lower mass comprising at least one soil contact plate;   a vibration exciter device that generates vibrations in the soil contact plate, the vibration exciter device having at least two individual exciters ( 13 );   
     wherein
 each of the individual exciters has a separate, individually driven imbalance shaft that bears an imbalance mass; and wherein 
 the individual exciters are capable of being individually controlled with respect to at least one of the rotational speed and the phase position of the respectively allocated imbalance shaft. 
 
   
   
       2 . The vibrating plate as recited in  claim 1 , wherein each of the individual exciters has a motor that rotationally drives the imbalance shaft, and has a position sensor that acquires the position of the imbalance shaft in at least one position. 
   
   
       3 . The vibrating plate as recited in  claim 1 , wherein
 a hydraulic valve is allocated to the hydraulic motor; and wherein   the individual exciter has a controller for evaluating a signal from the position sensor and for controlling the actuating element in such a way as to achieve at least one of a target rotational speed and a target phase position, prespecified to the controller, for the imbalance shaft.   
   
   
       4 . The vibrating plate as recited in  claim 1 , wherein a central control unit is provided for coordinating the controllers of the individual exciters and for specifying at least one of individual target rotational speed and a target phase position for each controller of the individual exciters, in such a way as to achieve a behavior of the soil contact plate that is at least one of desired by an operator and is specified by an operating or driving program. 
   
   
       5 . The vibrating plate as recited in  claim 1 , wherein
 a hydraulic valve is allocated to the hydraulic motor; and   a central controller is provided for evaluating the signals from the position sensors of the individual exciters and for individually controlling the actuating elements of the individual exciters in such a way as to achieve a behavior of the soil contact plate that is at least one of desired by an operator and is specified by an operating or driving program.   
   
   
       6 . The vibrating plate as recited in  claim 1 , wherein the imbalance shafts of the individual exciters are driven with the same rotational speed. 
   
   
       7 . The vibrating plate as recited in  claim 1 , wherein the imbalance shaft is driven by at least one of the individual exciters with a different rotational speed than the imbalance shafts of the other individual exciters. 
   
   
       8 . The vibrating plate as recited in  claim 7 , wherein the other rotational speed is an odd-numbered multiple, in particular three times or five times, of the rotational speed of the imbalance shafts of the other individual exciters. 
   
   
       9 . The vibrating plate as recited in  claim 1 , wherein at least one of the individual exciters is capable of being controlled in such a way that the imbalance shaft allocated to it intentionally achieves a non-uniform rotational speed. 
   
   
       10 . The vibrating plate as recited in  claim 1 , wherein
 a second vibration exciting device that generates vibrations in the soil contact plate is provided and has at least two imbalance shafts that are positively coupled to one another and that are driven so as to rotate in opposite directions; wherein   there is allocated to at least one of the imbalance shafts of the second vibration exciter device a position sensor for determining the phase position of this imbalance shaft; and wherein   a signal of the position sensor is supplied to at least one of the central control unit and the central controller in order to coordinate at least one of the rotational speed and the phase position of the imbalance shafts of the second vibration exciter device with the individual exciters.   
   
   
       11 . The vibrating plate as recited in  claim 1 , wherein the position sensor has a device for acquiring the angle of rotation. 
   
   
       12 . The vibrating plate as recited in  claim 1 , wherein at least one of the individual exciters and the second vibration exciter device are situated in a distributed fashion on a plurality of soil contact plates. 
   
   
       13 . The vibrating plate as recited in  claim 1 , wherein at least some of the imbalance shafts of the individual exciters are situated on the soil contact plate in such a way that the force vectors produced by them act in different planes. 
   
   
       14 . The vibrating plate as recited in  claim 1 , wherein at least some of the imbalance shafts of the individual exciters are situated on the soil contact plate in one of a star-shaped pattern, axially, parallel, and at an angle to one another. 
   
   
       15 . The vibrating plate as recited in  claim 1 , wherein at least one of the imbalance shafts bears a larger imbalance mass than do other imbalance shafts.