Automatic clutch control apparatus

Claim 2

A control apparatus for an automatic clutch for use in an automotive vehicle, said control apparatus comprising: a pressure regulating valve having a valve spool for selectively connecting clutch actuating pressure to line pressure and a drain, and control means for controlling said pressure regulating valve and including: means for providing signals indicative of vehicle inclination, braking torque and engine drive torque when the clutch is off, means operative under a condition where the engine drive torque is greater than the sum of the braking torque and a directionally adverse torque, which is due to vehicle inclination, attempting to move the vehicle in an adverse direction, for displacing the valve spool of said pressure regulating valve in a direction which will increase the clutch actuating pressure when the braking torque is smaller than the directionally adverse torque, and in a direction which will decrease the clutch actuating pressure when the braking torque is greater than said directionally adverse torque.

Claim 3

The control apparatus as defined in claim 1, wherein said clutch actuating pressure is increased by connecting to a line pressure and decreased by connecting to the drain.

Claim 4

A control apparatus for an automatic clutch for use in an automotive vehicle, said control apparatus comprising: a pressure regulating valve having a valve spool for selectively connecting clutch actuating pressure to line pressure and a drain, and control means for controlling said pressure regulating valve and including: means for providing signals indicative of vehicle inclination, braking torque and engine drive torque when the clutch is off; first calculating means for calculating a directionally adverse torque, which attempts to move the vehicle in an adverse direction, using the signal indicative of vehicle inclination; second calculating means for calculating the sum of the braking torque and the directionally adverse torque; first comparing means for comparing the engine drive torque and said sum; second comparing means for detecting if said sum is negative; and means for displacing the valve spool of said pressure regulating valve in a direction which will increase the clutch actuating pressure when said first comparing means produces a signal indicating that the engine drive torque is greater than said sum and, moreover, said second comparing means produces a signal indicating that said sum is negative; and in a direction which will decrease the clutch actuating pressure when said first comparing means produces a signal indicating that the engine drive torque is smaller than said sum or said second comparing means produces a signal indicating that said sum is not negative.

Claim 5

A control apparatus for an automatic clutch for use in an automotive vehicle, said control apparatus comprising: a pressure regulating valve having a valve spool for selectively connecting clutch actuating pressure to line pressure and a drain, and control means for controlling said pressure regulating valve and including: means for providing signals indicative of vehicle inclination, braking torque and engine drive torque when the clutch is off; first calculating means for calculating a directionally adverse torque, which attempts to move the vehicle in an adverse direction, using the signal indicative of vehicle inclination; second calculating means for calculating the sum of the braking torque and the directionally adverse torque; first comparing means for comparing the engine drive torque and said sum; second comparing means for detecting if said sum is negative; and means for displacing the valve spool of said pressure regulating valve in a direction which will increase the clutch actuating pressure when said first comparing means produces a signal indicating that the engine drive torque is greater than said sum and, moreover, said second comparing means produces a signal indicating that said sum is negative; and in a direction which will decrease the clutch actuating pressure when said first comparing means produces a signal indicating that the engine drive torque is smaller than said sum or said second comparing means produces a signal indicating that said sum is not negative.

Claim 6

The control apparatus as defined in claim 3, which further includes a shift position sensing means to sense the shift position when the clutch is off for providing a signal indicative of forward or rearward driving.

Claim 7

The control apparatus as defined in claim 4, wherein the second calculating means further includes means for making the value of the directionally adverse torque negative upon calculating said sum of the braking torque and the directionally adverse torque when said shift position sensing means provides a signal indicative of rearward driving.

Claim 8

The control apparatus as defined in claim 3, which further includes a third calculating means for calculating a signal indicative of a minimum clutch pressure when the first comparing means produces the signal indicating that the engine drive torque is smaller than said sum.

Claim 9

The control apparatus as defined in claim 3, wherein said first and second calculating means and said first and second comparing means for a calculating/comparing processing unit.

Claim 10

The control apparatus as defined in claim 3, wherein said clutch actuating pressure is increased by connecting to a line pressure and decreased by connecting to the drain.

Claim 11

A control apparatus for an automatic clutch for use in an automotive vehicle, said control apparatus comprising: a pressure regulating valve having a valve spool for selectively connecting clutch actuating pressure to line pressure and a drain, and control means for controlling said pressure regulating valve and including: sensing means for providing signals indicative of throttle opening, engine rotational speed, brake pressure and vehicle inclination when the clutch is off, calculating means for calculating an engine drive torque based on the signals indicative of the throttle opening and engine rotational speed, a braking torque based on the signal indicative of the brake pressure, and a downward torque, which attempts to move the vehicle downward, based on the signal of the vehicle inclination, and means operative under a condition where the engine drive torque is greater than the sum of the braking torque and the downward torque for displacing the valve spool of said pressure regulating valve in a direction which will increase the clutch actuating pressure when the braking torque is smaller than the downward torque, and in a direction which will decrease the clutch actuating pressure when the braking torque is greater than the downward torque.

Claim 12

A control apparatus for an automatic clutch for use in an automotive vehicle, said control apparatus comprising: a pressure regulating valve having a valve spool for selectively connecting clutch actuating pressure to line pressure and a drain, and control means for controlling said pressure regulating valve and including: sensing means for providing signals indicative of throttle opening, engine rotational speed, brake pressure and vehicle inclination when the clutch is off, calculating means for calculating an engine drive torque based on the signals indicative of the throttle opening and engine rotational speed, a braking torque based on the signal indicative of the brake pressure, and a downward torque, which attempts to move the vehicle downward, based on the signal of the vehicle inclination, and means operative under a condition where the engine drive torque is greater than the sum of the braking torque and the downward torque for displacing the valve spool of said pressure regulating valve in a direction which will increase the clutch actuating pressure when the braking torque is smaller than the downward torque, and in a direction which will decrease the clutch actuating pressure when the braking torque is greater than the downward torque.

Claim 13

The control apparatus as defined in claim 9, wherein said clutch actuating pressure is increased by connecting to a line pressure and decreased by connecting to the drain.

Claim 14

A control apparatus for an automatic clutch for use in an automotive vehicle, said control apparatus comprising: a pressure regulating valve having a valve spool for selectively connecting clutch actuating pressure to line pressure and a drain, and control means for controlling said pressure regulating valve and including: sensing means for providing signals indicative of throttle opening, engine rotational speed, brake pressure and vehicle inclination when the clutch is off; first calculating means for calculating a downward torque, which attempts to move the vehicle downward, using a signal indicative of vehicle inclination produced by using sensing means; second calculating means for calculating the sum of the braking torque and said downward torque, said braking torque being calculated based on the brake pressure signal from said sensing means; first comparing means for comparing the engine drive torque, and said sum, said engine drive torque being calculated based on the engine rotational speed signal; second comparing means for detecting if said sum is negative; and means for displacing the valve spool of said pressure regulating valve in a direction which will increase the clutch actuating pressure when said first comparing means produces a signal indicating that the engine drive torque is greater than said sum and, moreover, said second comparing means produces a signal indicating that said sum is negative; and in a direction which will decrease the clutch actuating pressure when said first comparing means produces signal indicating that the engine drive torque is smaller than said sum or said second comparing means produces a signal indicating that said sum is not negative.

Claim 15

A control apparatus for an automatic clutch for use in an automotive vehicle, said control apparatus comprising: a pressure regulating valve having a valve spool for selectively connecting clutch actuating pressure to line pressure and a drain, and control means for controlling said pressure regulating valve and including: sensing means for providing signals indicative of throttle opening, engine rotational speed, brake pressure and vehicle inclination when the clutch is off; first calculating means for calculating a downward torque, which attempts to move the vehicle downward, using a signal indicative of vehicle inclination produced by using sensing means; second calculating means for calculating the sum of the braking torque and said downward torque, said braking torque being calculated based on the brake pressure signal from said sensing means; first comparing means for comparing the engine drive torque, and said sum, said engine drive torque being calculated based on the engine rotational speed signal; second comparing means for detecting if said sum is negative; and means for displacing the valve spool of said pressure regulating valve in a direction which will increase the clutch actuating pressure when said first comparing means produces a signal indicating that the engine drive torque is greater than said sum and, moreover, said second comparing means produces a signal indicating that said sum is negative; and in a direction which will decrease the clutch actuating pressure when said first comparing means produces signal indicating that the engine drive torque is smaller than said sum or said second comparing means produces a signal indicating that said sum is not negative.

Claim 16

The control apparatus as defined in claim 11, wherein said first and second calculating means and said first and second comparing means form a calculating/comparing processing means.

Claim 17

The control apparatus as defined in claim 11, wherein said clutch actuating pressure is increased by connecting to a line pressure and decreased by connecting to the drain.