EP0990793A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Stop and restart device for vehicular engine
Assignee: Toyota Motor Corp
•
Filing: 1999-09-27
•
Granted: —
•
Expires: 2019-09-27
Abstract
Abstract An automatic engine stop and restart device for a vehicle provided with a brake booster using an intake negative pressure generated by the engine rotation as the boost source, is provided with a sensor for detecting the negative pressure of the brake booster. The engine is restarted (steps 180 and 190) when the negative pressure decreases to a predetermined value or less during engine stop. Sufficient surge tank negative pressure, that is, the brake booster negative pressure, is secured by restarting of the engine. This prevents the deterioration of the brake booster function resulting from increased engine stop frequency. <IMAGE>
Inventors
- 👤 Shuji Nagano
- 👤 Kojiro Kuramochi
- 👤 Atsushi Tabata
- 👤 Hatsuo Nakao
- 👤 Koichi Mizutani
- 👤 Tokuhisa Nomura
- 👤 Yasushi Kusaka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 17:24
CPC Classifications
B; B60; B60W; B60W30/00; B60W30/18; B60W30/18009; B60W30/18109; B60K; B60K6/00; B60K6/20; B60K6/22; B60K6/36; B60K6/365; B60K6/38; B60K6/383; B60K6/42; B60K6/48; B60W10/00; B60W10/18; B60W10/30; F; F02; F02N; F02N11/00; F02N11/08; F02N11/0814; F02N11/0818; F02N11/0833; F02N11/084; B60L; B60L2240/00; B60L2240/40; B60L2240/44; B60L2240/441; B60L2240/445; B60L2240/48; B60L2240/485; B60L2240/486; B60W20/00; B60W2510/00; B60W2510/06; B60W2510/0638; B60W2510/0676; B60W2510/068; B60W2510/0685; B60W2510/10; B60W2510/107; B60W2510/24; B60W2510/242; B60W2510/244; B60W2520/00; B60W2520/10; B60W2540/00; B60W2540/06; B60W2540/10; B60W2540/12; B60W2540/16; B60W2555/00; B60W2555/20; F02N2200/00; F02N2200/08; F02N2200/0801; F02N2200/0803; F02N2200/0807; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40; Y02T10/60; Y02T10/62
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
161 words
An engine stop and restart device, which is installed in a vehicle provided with
a brake assist means that generates an assist force for assisting a brake force, for
stopping an engine when predetermined stop conditions are met and restarting the
stopped engine when predetermined restart conditions are met, said device having
a vehicle condition detection means (steps 120, 304, 412, 506) for detecting a
vehicle condition when the engine is in a stopped state, characterized by an assist force request compliance determination means (steps 180, 280, 310, 414,
508, 630, 660) for determining, on the basis of the detection result from the
vehicle condition detection means, whether a request for the assist force can be
complied with in a sufficient manner, and a control means (steps 190, 312, 416, 514, 670) for restarting the engine when
said assist force request compliance determination means determines that the
request for the assist force can not be complied with in a sufficient manner.
Claim 2
Dependent Claim
129 words
An engine stop and restart device according to claim 1, characterized in that said vehicle condition detection means (steps 120, 304, 412, 506) comprises an
assist force associated value detection means for detecting an associated value
associated with the assist force when the engine is in the stopped state and that
said assist force request compliance determination means (steps 180, 280, 310,
414, 508, 630, 660) comprises an assist force decrease detection means for
detecting whether the associated value has become a critical value which
indicates that the assist force has become equal or less than a predetermined
value, wherein said control means (steps 190, 312, 416, 514, 670) restarts the
engine when said assist force decrease detection means detects that the associated
value has become said critical value.
Claim 3
Dependent Claim
41 words
An engine stop and restart device according to claim 1 or 2, characterized in: that said brake assist means is a vacuum servo type brake booster (105)
which uses negative pressure on an intake side of the engine as boost source.
Claim 4
Dependent Claim
79 words
The engine stop and restart device according to claim 3, characterized in: that said assist force associated value detection means (step 120) detects a
negative pressure of the brake booster as said associated value associated with the
assist force, and that the engine is restarted by said control means (step 190) when
said assist force decrease detection means (step 180) detects that the negative
pressure of said brake booster has become equal to or less than a predetermined
value.
Claim 5
Dependent Claim
90 words
An engine stop and restart device according to claim 3, characterized in: that said assist force associated value detection means (step 304) detects the
negative pressure of said brake booster at least twice as said associated value
associated with the assist force, and that the engine is restarted by said control
means (step 312) when said assist force decrease detection means (step 310)
detects that a negative pressure detected at a certain time has decreased from a
negative pressure detected prior to that time by a predetermined value or more.
Claim 6
Dependent Claim
81 words
An engine stop and restart device according to claim 3, characterized in: that said assist force associated value detection means (step 304) detects the
negative pressure on the engine intake side as said associated value associated
with the assist force, and that the engine is restarted by said control means (step
312) when said assist force decrease detection means (step 310) detects that the
negative pressure on the engine intake side has become equal to or less than a
predetermined value.
Claim 7
Dependent Claim
82 words
An engine stop and restart device according to claim 3, characterized in: that said assist force associated value detection means (steps 102 and 412)
detects a number of brake operations during engine stop as said associated value
associated with the assist force, and that the engine is restarted by said control
means (step 416) when said assist force decrease detection means (steps 280 and
414) detects that the number of brake operations has become equal to or greater
than a predetermined number.
Claim 8
Dependent Claim
32 words
An engine stop and restart device according to claim 7, characterized in: that the number of brake operations is the number of operations which a foot
brake pedal is depressed and released.
Claim 9
Dependent Claim
64 words
An engine stop and restart device according to claim 1, characterized in: that said vehicle condition detection means (step 506) detects a vehicle
speed during engine stop, and that the engine is restarted by said control means
(step 514) when said assist force request compliance determination means (steps
508 and 512) determines that the vehicle speed is maintained at a predetermined
value or more.
Claim 10
Dependent Claim
54 words
An engine stop and restart device according to claim 9, characterized in: that the engine is restarted by said control means (step 514) when said assist
force request compliance determination means (steps 508 and 512) determines
that the vehicle speed is maintained at a predetermined value or more for a
predetermined time or more.
Claim 11
Dependent Claim
115 words
An engine stop and restart device according to claim 3, characterized in: that said assist force associated value detection means (step 610) is provided
with a brake booster internal pressure detection means for detecting the internal
pressure of said brake booster, an atmospheric pressure detection means for
detecting an atmospheric pressure, and a pressure comparison means for
comparing the atmospheric pressure with the brake booster internal pressure; and
that the engine is restarted by said control means (step 670) when said assist
force decrease detection means (step 630) detects that a difference between the
atmospheric pressure and the brake booster internal pressure has become equal to
or less than a predetermined value during engine stop.
Claim 12
Dependent Claim
133 words
An engine stop and restart device according to claim 3, characterized in: that said assist force associated value detection means (step 610) is provided
with a brake booster internal pressure detection means for detecting the internal
pressure of said brake booster, an intake side negative pressure detection means
for detecting the negative pressure on the intake side of the engine, and a pressure
comparison means for comparing the intake side negative pressure and the brake
booster internal pressure; and that an automatic stop of the engine is permitted by
said control means (step 640) when said assist force decrease detection means
(steps 630 and 650) detects that the difference between the intake side negative
pressure and the brake booster internal pressure is equal to or less than a
predetermined value during engine operation.
Claim 13
Dependent Claim
68 words
An engine stop and restart device according to claims 1, 2 or 3, characterized
in: that said assist force associated value detection means detects the assist
force as the associated value associated with the assist force, and that the engine
is restarted by said control means when said assist force decrease detection means
detects that the assist force has become equal to or less than a predetermined
value.
Claim 14
Dependent Claim
57 words
An engine stop and restart device according to either one of the claims 1
through 11, characterized in: that said control means (steps 190, 312, 416, 514, and 670) is implemented
in order to prevent the assist force, generated by said brake assist means, from
decreasing to a value equal to or less than a predetermined value.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.