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US5156572A Expired / Lapsed US ⏱️ 0.0 years remaining

Speed shift control system of a continuous transmission

Assignee: Mazda Motor Corp
•
Filing: 1990-12-12
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Granted: 1992-10-20
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Expires: 2010-12-12
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Abstract

Abstract According to a gear shift control system of a continuous transmission of the present invention, when the gear ratio is controlled to a target gear ratio, a deviation between an actual primary pulley speed and the target primary pulley speed is detected. When a feedback-control is carried out to control the actual primary pulley speed to the target primary pulley speed on the basis of the above deviation, the control gain(s) is changed according to the deviation between the actual and the target primary pulley speeds at changing the gear ratio. Thus, the gear ratio is changed at the constant speed and better gear characteristics can be gained. Moreover, the hunting of the actual primary pulley speed occurred around the target speed can be prevented.

Inventors

  • 👤 Chitoshi Morishige

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 16:34
CPC Classifications
B; B60; B60W; B60W10/00; B60W10/04; B60W10/06; B60W10/10; B60W10/101; B60W30/00; B60W30/18; B60W30/1819; F; F16; F16H; F16H61/00; F16H61/66; F16H61/662; F16H61/66254; F16H61/66259

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 177 words
A speed shift control system of a continuous transmission having a primary and secondary pulley, a belt rotatably coupling said pulleys, and a regulator means for regulating an effective diameter of said primary pulley and said secondary pulley, said continuous transmission comprising: target speed determining means for determining a target primary pulley speed corresponding to a target gear ratio which varies according to a driving status; actual speed detecting means for detecting an actual speed of said primary pulley; control means for feedback-controlling said regulator means by a control gain so that the primary pulley speed is controlled to said target primary pulley speed on the basis of a speed deviation between said target primary pulley speed and said actual primary pulley speed obtained by said target speed determining means and said actual speed detecting means; and control gain changing means for changing control gains of said control means according to at least said deviation between said target primary pulley speed and said actual primary pulley speed wherein said control gain is inversely proportional to said deviation.
Claim 2
Dependent Claim 177 words
A speed shift control system of a continuous transmission having a primary and secondary pulley, a belt rotatably coupling said pulleys, and a regulator means for regulating an effective diameter of said primary pulley and said secondary pulley, said continuous transmission comprising: target speed determining means for determining a target primary pulley speed corresponding to a target gear ratio which varies according to a driving status; actual speed detecting means for detecting an actual speed of said primary pulley; control means for feedback-controlling said regulator means by a control gain so that the primary pulley speed is controlled to said target primary pulley speed on the basis of a speed deviation between said target primary pulley speed and said actual primary pulley speed obtained by said target speed determining means and said actual speed detecting means; and control gain changing means for changing control gains of said control means according to at least said deviation between said target primary pulley speed and said actual primary pulley speed wherein said control gain is inversely proportional to said deviation.
Claim 3
Dependent Claim 52 words
A speed shift control system of a continuous transmission as claimed in claim 1, wherein said primary and secondary pulley comprises a hydraulic cylinder, and an area for receiving a transmission fluid pressure in said primary pulley is larger than an area for receiving the transmission fluid pressure in said secondary pulley.
Claim 4
Dependent Claim 60 words
A speed shift control system of a continuous transmission as claimed in claim 2, wherein said regulator means comprises a gear ratio control valve for supplying a hydraulic pressure to and releasing a hydraulic pressure from said hydraulic cylinder of said primary pulley, and a duty solenoid valve for controlling sliding of a spool of said gear ratio control valve.
Claim 5
Dependent Claim 37 words
A speed shift control system of a continuous transmission as claimed in claim 1, wherein said target speed determing means sets a higher target primary pulley speed as an opening of an engine throttle valve gets large.
Claim 6
Dependent Claim 33 words
A speed shift control system of a continuous transmission as claimed in claim 1, wherein said control gains of said control means are an integral gain, a proportional gain, and a differential gain.
Claim 7
Dependent Claim 34 words
A speed shift control system of a continuous transmission as claimed in claim 1, wherein said control gain changing means changes a control gain of said control means according to a primary pulley speed.
Claim 8
Dependent Claim 34 words
A speed shift control system of a continuous transmission as claimed in claim 1, wherein said control gain changing means changes a control gain of said control means according to a secondary pulley speed.
Claim 9
Dependent Claim 47 words
A speed shift control system of a continuous transmission as claimed in claim 1, wherein said control gain changing means changes a control gain of said control means in inverse proportion to at least one of said actual primary pulley speed and an actual secondary pulley speed.
Claim 10
Dependent Claim 58 words
A speed shift control system of a continuous transmission as claimed in claim 8, wherein said control gain changing means calculates a parameter of control gain(s) which is obtained by multiplying a coefficient which is in inverse proportion to said actual primary pulley speed to a coefficient which is in inverse proportion to said actual secondary pulley speed.
Claim 11
Dependent Claim 47 words
A speed shift control system of a continuous transmission as claimed in claim 1, wherein said control gain changing means changes a control gain of said control means in inverse proportion to at least one of said target primary pulley speed and a target secondary pulley speed.
Claim 12
Dependent Claim 55 words
A speed shift control system of a continuous transmission as claimed in claim 10, wherein said control gain changing means calculates a parameter of control gain(s) which is obtained by dividing said actual primary pulley speed np 1 and calculating the parameter by said target primary pulley speed np 0 (np 1 /np 0 ).

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-10-20 1996-04-20 1996-10-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-10-20 2000-04-20 2000-10-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-10-20 2004-04-20 2004-10-20 $7700.00 Window Closed / Lapsed

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