Automatic centrifugal clutch with electric release and hysterisis means

A clutch comprising:

• first and second friction disks which are respectively connected for common rotation with a first and second rotatory element;
• clamping means for selectively and variably applying said friction disks into mutual frictional contact, thereby controlling the clutch between a slip condition and a grip condition;
• force-generating means for applying to the clamping means a first actuating force component which is substantially continuous at least when the clutch is in the grip condition, for maintaining the clutch in said grip condition;
• hysteresis means for automatically modifying the first actuating force component in a direction of release of the clutch when the clutch changes from the grip condition to the slip condition and in a contrary direction of increased clamping of the clutch when the clutch changes from the slip condition to the grip condition;
• power-means for generating a control-force;
• and
• control means for controlling selective application of said control force to the clamping means as a second actuating force component.

A clutch comprising:

• first and second friction disks which are respectively connected for common rotation with a first and a second rotatory element;
• clamping means for selectively and variably applying said friction disks into mutual frictional contact, thereby controlling the clutch between a slip condition and a grip condition according to whether an actuating force is applied to the clamping means in a clamping direction with a sufficient magnitude to allow the first and second disks to transmit a prevailing torque;
• force-generating means for applying to the clamping means a first force component of said actuating force;
• hysteresis means for automatically varying said first force component in a direction promoting slip condition of the clutch when the clutch changes from the grip condition to the slip condition and in a contrary direction promoting grip condition of the clutch when the clutch changes from the slip condition to the grip condition;
• and
• control means for selectively applying to the clamping means a control force-component of the actuating force.

A transmission device having at least two transmission ratios, comprising transmission elements which are in intermeshing relationship by means of gear teeth, a clutch mounted for selectively coupling together and uncoupling from each other two said transmission elements thereby determining which one of said transmission ratios prevails, said clutch comprising:

• first and second friction disks which are respectively connected for common rotation with a first and a second rotary element;
• clamping means for selectively and variably applying said friction disks into mutual frictional contact, thereby controlling the clutch between a slip condition and a grip condition according to whether an actuating force is applied to the clamping means in a clamping direction with a sufficient magnitude to allow the first and second disks to transmit a prevailing torque;
• force-generating means for applying to the clamping means a first force-component of said actuating force;
• hysteresis means for automatically varying said first force component in a direction promoting slip condition of the clutch when the clutch changes from the grip condition to the slip condition and in a contrary direction promoting grip condition of the clutch when the clutch changes from the slip condition to the grip condition;
• and
• control means for selectively applying to the clamping means a control component of the actuating force.