Power take off clutch engagement control system

In a vehicle having a power source for producing rotational motion, a power take-off (PTO) shaft for supplying rotational motion to at least one piece of equipment other than the vehicle, and a clutch including an input shaft coupled to the power source and an output shaft coupled to the PTO shaft, wherein the clutch includes a plurality of clutch plates operable to translate through a distance prior to clutch engagement and, upon clutch engagement, transmitted torque between the input and output shafts, a control system comprising:

• a clutch control configured to translate the clutch plates through the distance to engage the clutch plates in response to a first control signal;
• an output transducer disposed to generate an output signal representative of the rotational speed of the output shaft;
• and
• a control circuit coupled to the clutch control, and the output transducer, and being configured to monitor the output signal and apply the first control signal to the clutch control until the output signal is representative of a rotational speed of the output shaft greater than zero,
• wherein the torque transmitted by the clutch between the input and output shafts is dependent upon the pressure between the clutch plates and the clutch control is further configured to force the clutch plates together at pressure defined by second control signals applied to the clutch control, the system further comprising an input transducer disposed to generate an input signal representative of the rotational speed of the input shaft, the input transducer being coupled to the control circuit and the control circuit being further configured to monitor the input signal and, upon monitoring an output shaft speed greater than zero, applying second control signals to the clutch control to increase the pressure between the clutch plates at a pressurization rate which transmits torque from the input to the output shaft at levels which increase the rotational velocity of the output shaft at a rate less than a predetermined rate, and wherein the PTO shaft will fail at a predetermined maximum torque and the control circuit is further configured to apply third control signals to the clutch control upon determining that the input and output shafts are rotating at the same velocity, the third control signals controlling the clutch control to increase the pressure between the clutch plates at a predetermined pressure increase rate to maximum pressure which inhibits relative motion of the input and output shafts until the torque transferred between the shafts exceeds a predetermined limit which is less than the predetermined maximum torque.

A tractor comprising:

• a power source for producing rotational motion;
• a power take-off (PTO) shaft for supplying rotational motion to at least one piece of equipment;
• a clutch including an input shaft coupled to the power source and an output shaft coupled to the PTO shaft, wherein the clutch includes a plurality of clutch plates operable to translate through a distance prior to clutch engagement and, upon clutch plate engagement, transmitting torque between the input and output shafts;
• a clutch control coupled to the clutch and configured to translate the clutch plates through the distance to engage the clutch plates in response to a first control signal;
• an output transducer disposed to generated an output signal representative to the rotational speed of the output shaft;
• and
• a control circuit coupled to the clutch control, and the output transducer, and being configured to monitor the output signal and apply the first control signal to the clutch control until the output signal is representative of a rotational speed of the output shaft greater than zero.

A tractor comprising:

• a power source for producing rotational motion;
• a power take-off (PTO) shaft for supplying rotational motion to at least one piece of equipment;
• a clutch including an input shaft coupled to the power source and an output shaft coupled to the PTO shaft, wherein the clutch includes a plurality of clutch plates operable to translate through a distance prior to clutch engagement and, upon clutch engagement, transmitting torque between input and output shafts;
• a clutch control coupled to the clutch and configured to translate the clutch plates through the distance to engage the clutch plates in response to a first control signal;
• an output transducer disposed to generate an output signal representative or the rotational speed of the output shaft;
• and
• a control circuit coupled to the clutch control, and the output transducer, and the being configured to monitor the output signal and apply the first control signal to the clutch control until the output signal is representative of a rotational speed of the output shaft greater than zero,
• wherein the torque transmitted by the clutch between the input and output shafts is dependent upon the pressure between the clutch plates and the clutch control is further configured to force the clutch plates together at a pressure defined by second control signals applied to the clutch control, the system further comprising an input transducer disposed to generated an input signal representative of the rotational speed of the input shaft, the input transducer being coupled to the control circuit and the control circuit being further configured to monitor the input signal and, upon monitoring an output shaft speed greater than zero, applying second control signals to the clutch control to increase the pressure between the clutch plates at a pressurization rate which transmits torque from the input to the output shaft at levels which increase the rotational velocity of the output shaft at a rate less than a predetermined rate, and wherein the PTO shaft will fail at a predetermined maximum torque and the control circuit is further configured to apply third control signals to the clutch control upon determining that the input and output shafts are rotating at the same velocity, the third control signals controlling the clutch control to increase the pressure between the clutch plates at a predetermined pressure increase rate to a maximum pressure which inhibits relative motion of the input and output shafts until the torque transferred between the shafts exceeds a predetermined limit which is less than the predetermined maximum torque.

A power take-off (PTO) clutch control system for use in a tractor including a power take-off (PTO) shaft for supplying rotational motion to at least one piece of equipment other than the tractor, and a multi-plate clutch including an input shaft coupled to a power source and an output shaft coupled to the PTO shaft, wherein the clutch plates are operable to translate through a distance prior to clutch engagement and, upon clutch plate engagement, transmit torque between the input and output shafts, the system comprising:

• movement means for translating the clutch plates through the distance to engage the clutch plates in response to a first control signal;
• transducer means for generating an output signal representative of the rotational speed of the output shaft;
• and
• control means for monitoring the output signal and applying the first control signal to the clutch control until the output signal is representative of a rotational speed of the output shaft greater than zero.

A power take-off (PTO) clutch control system for use in a tractor including a power take-off (PTO) shaft for supplying rotational motion to at least one piece of equipment other than the tractor, and a multi-plate clutch including an input shaft coupled to a power source and an output shaft coupled to the PTO shaft, wherein the clutch plates are operable to translate through a distance prior to clutch engagement and, upon clutch plate engagement, transmit torque between the input and the output shafts, the system comprising:

• movement means for translating the clutch plates through the distance to engage the clutch plates in response to a first control signal;
• transducer means for generating an output signal representative of the rotational speed of the output shaft;
• and
• control means for monitoring the output signal and applying the first control signal to the clutch control until the output signal is representative of a rotational speed of the output shaft greater than zero;
• wherein the torque transmitted by the clutch plates between the input and output shafts is dependent on the pressure between the clutch plates and the movement means forces the clutch plates together at a pressure defined by second control signals applied to the movement means, the system further comprising an input means for generating an input signal representative of the rotational speed of the input shaft, the control circuit monitoring the input signal and, upon monitoring an output shaft speed greater than zero, applying second control signals to the movement means to increase the pressure between the clutch plates at a pressurization rate which transmits torque from the input to the output shaft at levels which increase the rotational velocity of the output shaft at a rate less than a predetermined rate, and wherein the PTO shaft will fail at a predetermined maximum torque and the control means applies third control signals to the movement means upon determining that the input and output shafts are rotating at the same velocity, the third control signals controlling the movement means to increase the pressure between the clutch plates at a predetermined pressure increase rate to a maximum pressure which inhibits relative motion of the input and output shafts until the torque transferred between the shafts exceeds a predetermined limit which is less than the predetermined maximum torque.