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US 6,685,594 B2Granted
Differential limiting device for a differential device
AssigneeFuji Jukogyo Kabushiki Kaisha
InventorKazuo Kanazawa
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AssigneeFuji Jukogyo Kabushiki Kaisha
InventorKazuo Kanazawa
Estimating the term…
A clutch drum is engaged to the rear part of a carrier of a center differential device. A clutch piston, which is rotated together with the rear drive shaft while allowing it to retractively move in a direction along a rear drive shaft, is provided within the clutch drum. Pinion shafts are protruded from the rear end face of the carrier to form protruded parts, which are confronted with the front end face of the clutch piston. A cam part, which is in sliding contact with the protruded parts, is formed on the front end of the clutch piston. When the carrier and the rear drive shaft relatively rotate, the protruded parts retractively move the clutch piston along cam crests of the cam part to press a clutch mechanism.
A differential limiting device of a differential device mounted on a four wheel drive vehicle having an engine for providing driving power to a front drive shaft and to a rear drive shaft, an automatic transmission mechanically and coaxially connected to a crankshaft of said engine for changing a rotational speed of the crankshaft in accordance with driving conditions, and a transmission output shaft included in said automatic transmission and coaxially connected to said crankshaft via a transmission input shaft for transmitting said driving power to both drive shafts, said differential device having a carrier directly and coaxially connected to said transmission output shaft for absorbing a relative rotational difference between said front drive shaft and said rear drive shaft, said differential limiting device coaxially mounted on said rear drive shaft for limiting said relative rotational difference, said differential limiting device comprising:
A differential limiting device of a differential device mounted on a four wheel drive vehicle having an engine for providing driving power to a front drive shaft at td to a rear drive shaft, an automatic transmission mechanically and coaxially connected to a crankshaft of said engine for changing a rotational speed of the crankshaft in accordance with diving conditions, and a transmission output shaft included in said automatic transmission and coaxially connected to said crankshaft via a transmission input shaft for transmitting said diving power to both drive shafts, said differential device having a carrier directly and coaxially connected to said transmission output shaft for absorbing a relative rotational difference between said front drive shaft and said rear drive shaft, said differential limiting device coaxially mounted on said rear drive shaft for limiting said relative rotational difference, said differential limiting device comprising:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Details of mechanically-actuated clutches not specific for one distinct type: mechanical clutch-actuating mechanisms arranged outside the clutch…
Having a transfer gear: the transfer gear being a differential gear
Arrangement or mounting of control devices for vehicle transmissions, or parts thereof, not otherwise provided for: for main transmission clutches
Mechanical clutch-actuating mechanisms arranged outside the clutch as such: clutch actuation by cams, ramps or ball-screw mechanisms
Term ended 1 Dec 2021 (estimated)
The present invention relates to a differential limiting device for a differential device, and particularly a differential limiting device for a differential device having a clutch mechanism.
By convention, a differential device is provide with a differential limiting device which additionally applies a predetermined differential limiting torque as an initial torque, and when one of the output shafts slips, it transmits a torque to the other output shaft by bypassing the one of output shaft.
A differential limiting device comprising a hydraulic multiple disc clutch is known. In a center differential device of the planetary gear type, disclosed in Japanese Patent Unexamined Publication No. Hei. 5-112149, a hydraulic multiple disc clutch is provided between a carrier and a drive shaft. The hydraulic multiple disc clutch generates a differential limiting torque depending on a slip of the rear wheel or the like. In this hydraulic multiple disc clutch, a differential limiting torque is generated by a multiple disc type clutch mechanism. Accordingly, a relatively large torque can be generated.
FIG. 1 is a diagram showing a mechanical arrangement of a drive force distribution device for a four-wheel drive vehicle, according to a first embodiment of the present invention;
FIG. 2 is a longitudinal sectional view showing a center differential device, according to the first embodiment;
FIG. 3 is a perspective view showing a clutch piston, according to the first embodiment;
The preferred embodiments of the invention will be described with reference to the accompanying drawings. FIGS. 1 through 7 show a first embodiment of the invention. Of those figures, FIG. 1 is a schematic diagram showing a power distribution system for a four-wheel drive vehicle, which is a first embodiment of the invention. FIG. 2 is a sectional view showing a center differential device. FIG. 3 is a perspective view showing a clutch piston. FIG. 4 is a development showing a cam part. FIG. 5 is an explanatory diagram useful in explaining an operation of a clutch piston, which is based on cam crests. FIG. 6 is an explanatory diagram for explaining a modification of a cam crest. FIG. 7 is an explanatory diagram for explaining another modification of a cam crest.
In FIG. 1, reference numeral 1 designates a transaxel, vertically mounted, which is a drive system for a four-wheel drive vehicle. The transaxel 1 includes a torque converter case 2 and a differential case 3, which are disposed in the front part of the transaxel 1, while being formed integrally with the transaxel 1. A transmission case 4 is joined to the rear ends of those cases 2 and 3. An extension case 5 is joined to the rear end of the transmission case 4. A power transmission device is installed within the extension case 5. An oil pan 6 is mounted on the lower side of the transmission case 4.
Reference numeral 10 designates an engine. A crank shaft 11 of the engine 10 is coupled to the input of a torque converter 13 having a lockup clutch 12, which is disposed within the torque converter case 2. A transmission input shaft 14 of an automatic transmission 30, which is placed in the transmission case 4, is coupled to the output side of the torque converter 13.