EP0075256A2
Expired / Lapsed
EP
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Lock-up control device and method for lock-up type automatic transmission
Assignee: Nissan Motor Co Ltd
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Filing: 1982-09-14
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Granted: —
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Expires: 2002-09-14
Abstract
Abstract A pulse train is generated which has a duration increasing as the vehicle speed decreases. A counter generates a period indicative signal indicative of a current period of the pulse train. A memory stores the period indicative signal for the succeeding period. An adder generates an adder signal indicative of the addition of a preset value to the period indicative signal stored in the memory. A comparator compares the adder signal with the period indicative signal generated by the period indicative signal generating means and generates a comparator signal when the former is larger than the latter. A flip-flop generates a flip-flop signal when the comparator signal occurs under the presence of a lock-up signal. An AND gate provides a lock-up release signal when said flip-flop signal occurs irrespective of the presence of the lock-up signal.
Inventors
- 👤 Tadashi Suzuki
- 👤 Yoshiro Morimoto
- 👤 Hideo Hamada
- 👤 Masaaki Suga
- 👤 Takashi Murasugi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 20:11
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/14; F16H61/143; F16H45/00; F16H45/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
131 words
A lock-up control device for a lock-up type automatic transmission of a vehicle, the lock-up type automatic transmission including a torque converter which is able to lock up, comprising: means for generating a pulse train having period variable depending upon the vehicle speed; means for allowing the torque converter to lock up in response to said pulse train; means for generating a period indicative signal indicative of current period of said pulse train; memory means for storing said period indicative signal for the succeeding period of the pulse train; and means for preventing the torque converter from locking up when a difference between said period indicative signal generated by said period indicative signal generating means and said period indicative signal stored in said memory means is larger than a preset value.
Claim 2
Dependent Claim
131 words
A lock-up control device for a lock-up type automatic transmission of a vehicle, the lock-up type automatic transmission including a torque converter which is able to lock up, comprising: means for generating a pulse train having period variable depending upon the vehicle speed; means for allowing the torque converter to lock up in response to said pulse train; means for generating a period indicative signal indicative of current period of said pulse train; memory means for storing said period indicative signal for the succeeding period of the pulse train; and means for preventing the torque converter from locking up when a difference between said period indicative signal generated by said period indicative signal generating means and said period indicative signal stored in said memory means is larger than a preset value.
Claim 3
Dependent Claim
22 words
A lock-up control device as claimed in claim 1, wherein the period of said pulse train increases as the vehicle speed decreases.
Claim 4
Dependent Claim
51 words
A lock-up control device as claimed in claim 2, wherein said period indicative signal generating means includes a timer means for generating clock pulses and a counter means responsive to said pulse train and said clock pulses for counting the number of said clock pulses and generating said period indicative signal.
Claim 5
Dependent Claim
27 words
A lock-up control device as claimed in claim 3, wherein said means for allowing the torque converter to lock up includes means for generating a lock-up signal.
Claim 6
Dependent Claim
177 words
A lock-up control device as claimed in claim 4, wherein said means for preventing the torque converter from locking up includes an adder means for adding said preset value to said period indicative signal stored in said memory means and generating an adder signal indicative of the result of the addition, a comparator means for comparing said adder signal with said period indicative signal generated by said period indicative signal generating means and generating a comparator signal when said adder signal is larger than said period indicative signal generated by said period indicative signal generating means, a flip-flop means receiving said lock-up signal and said comparator signal for generating a flip-flop signal when said comparator signal occurs under the presence of said lock-up signal, a gate means receiving said lock-up signal and said flip-flop signal for generating a lock-up release signal in response to the occurrence of said flip-flop signal irrespective of the occurrence of said lock-up signal, and means for releasing the torque converter from the lock-up state thereof in response to said lock-up release signal.
Claim 7
Dependent Claim
120 words
A lock-up control method for a lock-up type automatic transmission of a vehicle, the lock-up type automatic transmission including a torque converter which is able to lock up, comprising: generating a pulse train having period variable depending upon the vehicle speed; allowing the torque converter to lock up in response to said pulse train; generating a period indicative signal indicative of current period of said pulse train; storing said period indicative signal for the succeeding period of the pulse train; and preventing the torque converter from locking up when a difference between said period indicative signal generated by said period indicative signal generating means and said period indicative signal stored in said memory means is larger than a preset value.
Claim 8
Dependent Claim
120 words
A lock-up control method for a lock-up type automatic transmission of a vehicle, the lock-up type automatic transmission including a torque converter which is able to lock up, comprising: generating a pulse train having period variable depending upon the vehicle speed; allowing the torque converter to lock up in response to said pulse train; generating a period indicative signal indicative of current period of said pulse train; storing said period indicative signal for the succeeding period of the pulse train; and preventing the torque converter from locking up when a difference between said period indicative signal generated by said period indicative signal generating means and said period indicative signal stored in said memory means is larger than a preset value.
References Cited (Backward Citations)
No citation records indexed.
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