Clutch automation device

• US 4,799,160 A
• Filed: 11/07/1985
• Issued: 01/17/1989
• Est. Priority Date: 11/07/1984
• Status: Expired due to Term

• Current Assignee: Renault Agriculture
• Original Assignee: Renault Agriculture
• Inventors: Drutel, Yves, Arbeille, Yves, Viguier, Alain
• Primary Examiner(s): Gruber, Felix D.
• Application Number:
  US06/795,943
• Time in Patent Office: 1,167 Days
• Field of Search: 364/424, 364/424.1, 192/0.073, 192/0.074, 192/0.075, 192/0.076, 192/3.58
• US Class Current: 701/67
• CPC Class Codes: B60W 2050/0045 using databus protocols
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2710/023 Clutch engagement rate
• CPC Class Codes: B60W 2720/106 Longitudinal acceleration
• CPC Class Codes: F16D 2048/0272 Two valves, where one valve is supplying fluid to the cylinder and the other valve is for draining fluid to the sump
• CPC Class Codes: F16D 2048/0275 Two valves arranged in parallel, e.g. one for coarse and the other for fine control during supplying or draining fluid from the actuation cylinder
• CPC Class Codes: F16D 2500/10481 Automatic clutch, e.g. centrifugal masses
• CPC Class Codes: F16D 2500/3067 Speed of the engine
• CPC Class Codes: F16D 2500/3115 Vehicle wheel speed
• CPC Class Codes: F16D 2500/7041 Position
• CPC Class Codes: F16D 2500/70418 Current
• CPC Class Codes: F16D 48/066 Control of fluid pressure, e.g. using an accumulator F16D48/062, F16D48/068 take precedence
• CPC Class Codes: F16D 48/068 using signals from a manually actuated gearshift linkage

Abstract

A device for automizing a vehicle clutch having at least one single-action hydraulic jack includes two solenoid valves or an equivalent assembly, two pulse sensors for respectively detecting the speed of the wheels and the engine speed of the vehicle, an actuating contact and an electronic cirucit connected to the solenoid valves, the sensor and the contact. The electronic circuit controls declutching and clutching to provide gradual controlled engaging of the clutch according to data relating to the engine speed and vehicle acceleration.

Claims

1. A device for controlling engagement of a hydraulic clutch having a jack, said device comprising:

a first hydraulic control valve having a first solenoid for regulating fluid flow from a pressurized hydraulic fluid source to the jack to urge the clutch to engage;

a second hydraulic control valve having a second solenoid for regulating fluid from the jack to a reservoir to allow the clutch to disengage;

an actuating contact for providing a clutch operation signal indicating operation of the clutch;

a first pulse sensor for monitoring engine speed of a vehicle and providing an engine speed signal proportional to the monitored vehicle engine speed;

a second pulse sensor for monitoring wheel speed of a vehicle and providing a wheel speed signal proportional to the monitored vehicle wheel speed; and

electronic control circuitry responsive to the clutch operation signal for controlling the first and second hydraulic valves to cause the clutch to engage gradually, the electronic control circuitry including calculating means, valve control signal generating means, and means for regulating the valve control signal generating means;

the calculating means receiving the engine speed signal and the wheel speed signal from the pulse sensors and calculating the vehicle engine speed and wheel speed therefrom, the valve control signal generating means generating first and second pulsed valve control signals having a common constant frequency and having current carrying times limited to vary between, but without reaching, a current carrying time causing constant energization of the solenoids and a current carrying time insufficient for energization of the solenoids, and the regulating means regulating the valve control signal generating means according to the engine speed and wheel speed of the vehicle as calculated by the calculating means to alternatively generate the first valve control signal with a relatively greater current carrying time than the second valve control signal, to cause the jack to be filled with fluid passed by the first control valve, or the first valve control signal with a relatively lesser current carrying time than the second valve control signal, to cause the jack to discharge fluid through the second control valve.

2. A device as claimed in claim 1, wherein:

(a) the electronic control circuitry comprises means for applying clock signals to the valve control signal generating means;

(b) the means for regulating the valve control signal generating means comprises a microprocessor including a central processing unit, a read only memory and a read-write memory;

(c) the valve control signal generating means comprises

(i) interrupt means,

(ii) a first timer connected to the first pulse sensor and the clock signal applying means and having first counter means for counting applied clock pulses received between successive pulses from the first pulse sensor and providing data indicative thereof to the microprocessor after interruption of the microprocessor by the interrupt means, and

(iii) a second timer connected to the second pulse sensor and the clock signal applying means and having second counter means for counting applied clock pulses received between successive pulses received from the second pulse sensor and providing data indicative thereof to the microprocessor after interruption of the microprocessor by the interrupt means; and

(d) the central processing unit includes means operative after interruption of the microprocessor by the interrupt means for

(i) calculating wheel speed, engine speed, and vehicle acceleration vlues from the provided data and determining therefrom the constant frequency and the current carrying times for the valve control signals,

(ii) determining a constant frequency for calculating acceleration, and

(iii) causing the valve control signal generating means to generate the first and second valve control signals accordingly.