192 clutches and power-stop control – Transmission control and clutch control – Common control
Reexamination Certificate
2000-10-04
2002-09-03
Lorence, Richard M. (Department: 3681)
192 clutches and power-stop control
Transmission control and clutch control
Common control
C192S003620, C192S003630, C192S085060
Reexamination Certificate
active
06443278
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a power transmission apparatus for a vehicle having a hydraulic pressure type clutch capable of transmitting and cutting power between a crankshaft of an engine and driving wheels, and a clutch control valve for controlling hydraulic pressure provided to the clutch.
2. Description of Related Art
A power transmission apparatus is known from, for example, Japanese Patent Laid-Open No. S47-40417. However, according to the above-described reference, the clutch control valve is an electromagnetic opening and closing valve for communicating and cutting a hydraulic pump and a hydraulic clutch. The clutch control valve only achieves the function of switching to supply and cut hydraulic pressure to the hydraulic clutch. Accordingly, operational characteristic of the hydraulic clutch is constant. Furthermore, an adjuster mechanism is needed for the hydraulic clutch to compensate for a wear amount of the clutch plates.
SUMMARY OF THE INVENTION
The present invention has been carried out in view of the above-mentioned situation. Accordingly, it is an object of the present invention to provide a power transmission apparatus for a vehicle which can vary the operational characteristics of a hydraulic clutch and dispense with an adjuster mechanism for compensating for a wear amount of clutch plates.
In order to achieve the above-described object, a first aspect of the present invention includes a power transmission apparatus for a vehicle having a hydraulic pressure type clutch capable of switching to transmit and cut power between a crankshaft of an engine and driving wheels, and a clutch control valve for controlling hydraulic pressure provided to the clutch, the clutch control valve comprises a valve housing having an input port connected to a hydraulic pump and an output port connected to the clutch, a spool capable of switching to communicate and cut between the input port and the output port and slidably fitted to the valve housing, and a linear solenoid coaxially connected to the spool and constituted such that output hydraulic pressure from the output port can be controlled to a value in correspondence with input current to the linear solenoid.
According to the above construction, the output hydraulic pressure of the clutch control valve and accordingly, hydraulic pressure provided to the clutch can be controlled by controlling the input current to the linear solenoid. By controlling the hydraulic pressure provided to the clutch, the operational characteristic of the clutch can be changed. By the change in the operational characteristic, a wear amount of clutch plates can be compensated for. Accordingly, it is unnecessary to provide an adjuster mechanism for the clutch.
Furthermore, a second aspect of the present invention includes, in addition to the construction of the first aspect, a gear transmission provided between the clutch and the driving wheels such that a plurality of shift stages of gear trains are selectively established, an actuator for driving to shift the gear transmission, and a control unit for controlling the actuator and the linear solenoid such that the clutch is operated to cut and connect in cooperation with shift operation of the gear transmission. According to such a construction, the clutch can be operated to cut and connect automatically in cooperation with driving to shift the gear transmission by the actuator. Therefore, the operational characteristics of the clutch can be changed. Accordingly, shift shock can be alleviated.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
REFERENCES:
patent: 5868167 (1999-02-01), Miki et al.
patent: 5957260 (1999-09-01), Kunii
patent: 47-40717 (1972-12-01), None
Hori Yoshiaki
Takano Noriaki
Birch & Stewart Kolasch & Birch, LLP
Honda Giken Kogyo Kabushiki Kaisha
Lorence Richard M.
LandOfFree
Power transmission apparatus for a vehicle does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Power transmission apparatus for a vehicle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Power transmission apparatus for a vehicle will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2842385