Control unit for an automatic transmission

• US 5,709,134 A
• Filed: 10/29/1996
• Issued: 01/20/1998
• Est. Priority Date: 04/29/1994
• Status: Expired due to Fees

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Ulm, Michael
• Primary Examiner(s): Marmor, Charles A.
• Assistant Examiner(s): Battista, Mary Ann
• Application Number:
  US08/738,624
• Time in Patent Office: 448 Days
• Field of Search: 74/606 R, 174/52.2
• US Class Current: 74/606.00R
• CPC Class Codes: B60R 16/0239 Electronic boxes
• CPC Class Codes: F16H 59/36 Inputs being a function of speed
• CPC Class Codes: F16H 61/0009 Hydraulic control units for transmission control, e.g. assembly of valve plates or valve units
• CPC Class Codes: G01P 1/026 for speed measuring devices, e.g. pulse generator
• CPC Class Codes: H05K 5/0056 characterized by features for protecting electronic components against vibration and moisture, e.g. potting, holders for relatively large capacitors
• CPC Class Codes: H05K 5/0065 wherein modules are associated together, e.g. electromechanical assemblies, modular structures
• CPC Class Codes: H05K 5/0082 specially adapted for transmission control units, e.g. gearbox controllers
• CPC Class Codes: Y10T 74/2186 Gear casings

Abstract

A control unit for an automatic transmission in a motor vehicle includes a housing having an open bottom part with an interior. A carrier is disposed in the housing. Circuit components are disposed on the carrier. Valve coils for electromagnetic hydraulic valves are disposed in the housing and embedded in a flexible compound. A rotational-speed sensor disposed in the interior of the open bottom part is embedded in the flexible compound and thus fixed in its position in the housing. The rotational-speed sensor extends into the vicinity of a gearwheel or of some other rotating component of the transmission and detects or records its rotary motion by induction or the Hall effect.

Claims

1. In a motor vehicle having an automatic transmission with a transmission housing, electromagnetic hydraulic valves and a rotating part disposed in the transmission housing, a control unit for the automatic transmission, comprising:

a housing having an open bottom part with an interior;

a carrier disposed in said housing;

circuit components disposed on said carrier;

valve coils for the electromagnetic hydraulic valves, said valve coils being disposed in said housing;

a flexible compound in which said valve coils are embedded; and

a rotational-speed sensor disposed in said interior of said open bottom part and embedded in said flexible compound, for detecting rotary motion of the rotating part in the transmission housing.

2. The control unit according to claim 1, wherein said rotational-speed sensor is an inductive sensor.

3. The control unit according to claim 1, wherein said rotational-speed sensor is a Hall-effect sensor.

4. The control unit according to claim 1, wherein said rotational-speed sensor is electrically connected to said circuit components on said carrier.