Handwheel-operated device

Abstract

A handwheel-operated device comprising a body, a handwheel and a chuck, the handwheel and the chuck being rotatable relative to the body, and the device further comprising a first motor operable to rotate the chuck, first sensor means responsive to rotation of the handwheel and first control means operable in conjunction with the first sensor means to cause the first motor to rotate the chuck in dependence upon an angular displacement and/or angular velocity of the handwheel.

1 - 45 . (canceled)  
   
   
       46 . A handwheel-operated device comprising a body, a handwheel and a chuck, the handwheel and the chuck being rotatable relative to the body, and the device further comprising a first motor operable to rotate the chuck, first sensor means responsive to rotation of the handwheel and first control means operable in conjunction with the first sensor means to cause the first motor to rotate the chuck in dependence upon an angular displacement and/or angular velocity of the handwheel.  
   
   
       47 . A device according to  claim 46 , wherein the first control means is operable to modulate a voltage applied to the first motor.  
   
   
       48 . A device according to  claim 47 , wherein the first control means is operable to modulate the voltage applied to the first motor such that the magnitude of the voltage is substantially proportional to the angular velocity of the handwheel.  
   
   
       49 . A device according to  claim 47 , wherein the first control means is operable to modulate the voltage applied to the first motor such that an angular displacement and/or angular velocity of the handwheel results in a corresponding angular displacement and/or angular velocity of the chuck.  
   
   
       50 . A device according to  claim 47 , wherein the first control means is operable to modulate the voltage applied to the first motor in dependence upon the angular velocity of the handwheel such that the angular velocity of the chuck is non-linearly related to the angular velocity of the handwheel, the ratio of handwheel angular velocity to chuck angular velocity decreasing with increasing handwheel angular velocity.  
   
   
       51 . A device according to  claim 46 , further comprising a variable low-pass signal filter operable to receive signals representative of the angular displacement and/or angular velocity of the handwheel from the first sensor means and to transmit signals below a cut-off frequency to the first control means and to attenuate signals above the cut-off frequency so as to prevent them from reaching the first control means, the cut-off frequency being determined by the angular velocity of the handwheel.  
   
   
       52 . A device according to  claim 46 , wherein the first sensor means comprises an angular displacement sensor.  
   
   
       53 . A device according to  claim 52 , wherein a first gear wheel is attached to a shaft of the angular displacement sensor, a second gear wheel is attached to the handwheel, and the first and second gear wheels are engageable with one another either directly or via one or more intermediate gears, so that each revolution of the second gear wheel causes the first gear wheel to rotate through more than 360°.  
   
   
       54 . A device according to  claim 53 , wherein the first sensor means comprises a second motor, a shaft of which is coupled for rotation to the handwheel, and measurement means for measuring one or more parameters related to a speed and direction of rotation of the shaft of the second motor, and computation means operable to derive a speed and direction of rotation of the shaft of the second motor, and hence a speed and direction of rotation of the handwheel, from the one or more measured parameters.  
   
   
       55 . A device according to  claim 54 , wherein the shaft of the angular displacement sensor is coupled for rotation to the rotor of the second motor, and the first gear wheel is attached to the shaft of the second motor.  
   
   
       56 . A device according to  claim 54 , further comprising second sensor means operable to determine a torque developed by the first motor, torque feedback means coupled to the handwheel and second control means operable in conjunction with the second sensor means to cause the torque feedback means to oppose the rotation of the handwheel.  
   
   
       57 . A device according to  claim 56 , wherein the torque feedback means comprises a variable brake engageable with the handwheel under the control of the second control means.  
   
   
       58 . A device according to  claim 56 , wherein the torque feedback means comprises a second control means that is operable to supply current to the second motor so as to oppose the rotation of the handwheel.  
   
   
       59 . A device according to  claim 46 , further comprising a battery to allow the device to be operated cordlessly, and third sensor means operable to determine an electromotive force (emf) developed by the battery, the first control means being operable in conjunction with the third sensor means to modulate the voltage applied to the first motor so that, at least until the battery is substantially discharged, decreases in the emf developed by the battery do not cause decreases of the speed of rotation of the chuck.  
   
   
       60 . A device according to  claim 46 , further comprising biasing means and mechanical braking means, the biasing means being operable to urge the mechanical braking means into engagement with the handwheel so as to oppose the rotation of the handwheel.  
   
   
       61 . A device according to  claim 46 , wherein the handwheel is provided with a handle moveable between a folded position and an extended position.  
   
   
       62 . A device according to  claim 61 , wherein the body of the device and the handle of the handwheel are formed such that in the folded position the handle engages with the body so as to prevent rotation of the handle relative to the body.  
   
   
       63 . A device according to  claim 61 , further comprising first switch means engageable with the handle, such that the first control means is operable to cause the first motor to rotate the chuck only when the handle is in the extended position.  
   
   
       64 . A device according to  claim 46 , wherein the body of the device comprises a first portion to which the handwheel is attached and a second portion attached to, and movable between a first and a second position relative to, the first portion.  
   
   
       65 . A device according to  claim 64 , further comprising switch means operable by the first or second portion such that the switch means is closed when the second portion is in the first position and open when the second portion is in the second position and the first control means is operable when the switch means is closed to cause the chuck to rotate in one sense when the * handwheel is rotated in a first sense, and operable when the switch means is open to cause the chuck to rotate in the opposite sense when the handwheel is rotated in the first sense.  
   
   
       66 . A method of controlling a motor of a handwheel-operated device, the device having a body, a handwheel, a chuck and a motor, the handwheel being rotatable relative to the body and the motor being operable to rotate the chuck relative to the body, the method comprising sensing rotation of the handwheel and causing the motor to rotate the chuck in dependence upon the angular displacement and/or angular velocity of the handwheel.