Center casting and governor for automatic transmission clutch

1 . An automatic transmission having a series of clutches and front and rear servos engageable in various combinations to provide different multiple forward gears and a reverse gear, comprising:

a valve body with a central casting;

a governor body operatively connected to the central casting and to the bands; and

hydraulic circuitry in the central casting providing fluid communications with the governor body to apply the rear servo in drive range first gear; and

the hydraulic circuitry including a rear servo circuit with holes to allow fluid flow to the governor body.

2 . The automatic transmission of claim 1 , wherein the central casting has a smooth surface to seal with the governor body.

3 . The automatic transmission of claim 1 , the governor body includes fluid circuitry and a valve moveable between open and closed positions, wherein fluid flows from the governor body to holes in the central casting to the rear servo circuit when the valve is in the open position and thereby apply the rear servo, and wherein such fluid flow is precluded when the valve is in the closed position.

4 . The automatic transmission of claim 1 , wherein the hydraulic circuit includes first and second gear circuits, and a hole in the second gear circuit to create a fluid passage to the governor body.

5 . The automatic transmission of claim 1 , wherein the governor body includes a solenoid and a pressure sensor.

6 . The automatic transmission of claim 5 , wherein the governor body includes a line pressure circuit to supply hydraulic fluid to the solenoid and a governor circuit to supply hydraulic fluid to the sensor.

7 . The automatic transmission of claim 6 , wherein the governor body includes a hole to connect the line pressure circuit to a fluid passage.

8 . The automatic transmission of claim 7 , further comprising a check ball in the hole and a spring to allow movement of the check ball between open and closed positions, whereby fluid flows through the hole to the fluid passage when the check ball is in the open position and fluid flow through the hole to the fluid passage is precluded when the check ball is in the closed position.

9 . A method of braking an automatic transmission having forward gears, a rearward gear, and clutches with front and rear bands, the method comprising:

providing a central casting having hydraulic circuitry coupled to a governor body and to the front and rear bands such that the rear band is applied in drive range 1st gear; and

applying and releasing the rear band via a valve in the governor body.

10 . The method of claim 9 , further comprising moving the valve between open and closed positions to apply and release the rear band, respectively.

11 . The method of claim 10 , further comprising exhausting hydraulic fluid when the valve is closed.

12 . The method of claim 9 , wherein the rear band releases when the automatic transmission shifts out of drive range 1st gear.

13 . An automatic transmission having a series of clutches and front and rear servos engageable in various combinations to provide different multiple forward gears and a reverse gear, comprising:

a valve body with a central casting;

a governor body operatively connected to the central casting and to the bands; and

hydraulic circuitry in the central casting providing fluid communications with the governor body to apply the rear servo in drive range first gear; and

the governor body including a valve to apply and release the rear servo.

14 . An automatic transmission having a series of clutches and front and rear servos engageable in various combinations to provide different multiple forward gears and a reverse gear, comprising:

a valve body with a central casting;

a governor body operatively connected to the central casting and to the bands; and

hydraulic circuitry in the central casting providing fluid communications with the governor body to apply the rear servo in drive range first gear; and

the governor body including fluid circuitry and a valve moveable between open and closed positions, wherein fluid flows from the governor body to holes in the central casting to the rear servo circuit when the valve is in the open position and thereby apply the rear servo, and wherein such fluid flow is precluded when the valve is in the closed position.

15 . The automatic transmission of claim 14 , wherein the governor body includes an exhaust port for the fluid circuitry, the exhaust port being closed when the valve is open and being open when the valve is closed.

16 . An automatic transmission having a series of clutches and front and rear servos engageable in various combinations to provide different multiple forward gears and a reverse gear, comprising:

a valve body with a central casting;

a governor body operatively connected to the central casting and to the bands; and

hydraulic circuitry in the central casting providing fluid communications with the governor body to apply the rear servo in drive range first gear; and

the hydraulic circuit including first and second gear circuits, and a hole in the second gear circuit to create a fluid passage to the governor body.

17 . An automatic transmission having a series of clutches and front and rear servos engageable in various combinations to provide different multiple forward gears and a reverse gear, comprising:

a valve body with a central casting;

a governor body operatively connected to the central casting and to the bands; and

hydraulic circuitry in the central casting providing fluid communications with the governor body to apply the rear servo in drive range first gear;

the governor body including a solenoid and a pressure sensor;

the governor body including a line pressure circuit to supply hydraulic fluid to the solenoid and a governor circuit to supply hydraulic fluid to the sensor; and

the governor body including a hole to connect the line pressure circuit to a fluid passage.