EP0040301A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Lock-up type automatic transmission
Assignee: Nissan Motor Co Ltd
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Filing: 1981-03-11
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Granted: —
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Expires: 2001-03-11
Abstract
Abstract lock-up type automatic transmission having a lock-up clutch between the pump impeller and the turbine runner of the torque converter. Control means for engaging and disengaging the lock-up clutch includes a lock-up control valve, a solenoid valve to control the shifting of the lock-up control valve, lock-up decision circuit means for producing a lock-up permission signal, shifting operation detector circuit means for producing a shift pulse signal, and a solenoid valve control means for controlling the solenoid valveto effect engagement of the lock-up clutch under conditions when the lock-up permission signal is present and the shift signal is not present, but to effect temporal disengagement of the lock-up clutch in response to the presence of the shift signal even when the lock-up permission signal is present. A delay means is provided to retard the appearance of the shift signal from the appearance of a demand for the shifting from one gear ratio to another gear ratio.
Inventors
- 👤 Masaaki A-624 Nishiterao-Ryo Suga
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 00:08
CPC Classifications
F; F16; F16H; F16H59/00; F16H59/68; F16H61/00; F16H61/14; F16H61/143; F16H41/00; F16H41/24; F16H2041/246; F16H2059/6807; F16H61/02; F16H61/0262; F16H61/0276
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
193 words
A lock-up type automatic transmission comprising: a torque converter having a pump impeller and a turbine runner; a lock-up clutch having a clutch piston drivingly connected to said turbine runner and being selectively engageable with said pump impeller; and control means for engaging and disengaging said lock-up clutch, said control means including a lock-up control valve, a solenoid valve to control the shifting of said lock-up control valve, lock-up decision means for producing a lock-up permission signal, shifting operation detector means for producing a shift signal having a predetermined duration time in response to the appearance of a demand for the shifting between two gear ratios in the transmission, solenoid valve control means for controlling said solenoid valve to effect engagement of said lock-up clutch under conditions when said lock-up permission signal is present and said shift signal is not present, but to effect temporal disengagement of said lock-up clutch during the presence of said shift signal even when said lock-up permission signal is present, and delay means for retarding the appearance of said shift signal by a predetermined amount of time which starts from the appearance of said command for the shifting.
Claim 2
Dependent Claim
193 words
A lock-up type automatic transmission comprising: a torque converter having a pump impeller and a turbine runner; a lock-up clutch having a clutch piston drivingly connected to said turbine runner and being selectively engageable with said pump impeller; and control means for engaging and disengaging said lock-up clutch, said control means including a lock-up control valve, a solenoid valve to control the shifting of said lock-up control valve, lock-up decision means for producing a lock-up permission signal, shifting operation detector means for producing a shift signal having a predetermined duration time in response to the appearance of a demand for the shifting between two gear ratios in the transmission, solenoid valve control means for controlling said solenoid valve to effect engagement of said lock-up clutch under conditions when said lock-up permission signal is present and said shift signal is not present, but to effect temporal disengagement of said lock-up clutch during the presence of said shift signal even when said lock-up permission signal is present, and delay means for retarding the appearance of said shift signal by a predetermined amount of time which starts from the appearance of said command for the shifting.
Claim 3
Dependent Claim
130 words
A lock-up type automatic transmission as claimed in claim 1, including a shift valve having an axially movable spool and a stationary electrical contact cooperating with said axially movable spool to form shift switch means for changing an output signal thereof from one level to another level upon axial movement of said axially movable spool, and wherein said shifting operation detector means includes a trigger pulse generating means connected to said shift switch means through said delay means, whereby the transmission of a change in level of the output signal of said switch means to said trigger pulse generating means is delayed and said trigger pulse generating means produces said shift signal upon receiving said change in level of the output signal of said switch means from said delay means.
Claim 4
Dependent Claim
97 words
A lock-up type automatic transmission as claimed in claim 2, including vehicle speed sensor means for producing a vehicle speed signal proportional to the vehicle speed, and wherein said lock-up decision means includes a vehicle speed comparator connected to said vehicle speed sensor means, a gear ratio detector connected to said shift switch means and logic means connected to said vehicle speed comparator and said gear ratio detector for producing said lock-up permission signal when said vehicle speed signal is higher than a predetermined vehicle speed value in each of said forward gear ratios of the transmission.
References Cited (Backward Citations)
No citation records indexed.
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