초록 ▼

A range shift arrangement is disclosed for shifting a gear reduction unit between a low-range operating speed and a high-range operating speed, or any speed range in-between. This arrangement is particularly adapted for use in vehicle power transfer devices, such as four-wheel drive transfer cases,

A range shift arrangement is disclosed for shifting a gear reduction unit between a low-range operating speed and a high-range operating speed, or any speed range in-between. This arrangement is particularly adapted for use in vehicle power transfer devices, such as four-wheel drive transfer cases, for allowing the operator to shift "on-the-move:" between a low-range drive mode and a high-range drive mode, or any range therebetween. In the preferred embodiment, the gear reduction unit includes a first component driven by the input shaft, a second component driving the output shaft, and a third component driven by a worm gearset. The worm gearset includes a worm gear fixed to the third component and a worm meshed with the worm gear. A variable speed motor is operable to drive the worm so as to vary the rotary speed of the third component, thereby varying the speed ratio between the input and output shafts.

대표청구항 ▼

1. A transfer case comprising:an input shaft; an output shaft; a gear reduction unit having a first component driven by said input shaft; a second component driving said output shaft, and a rotatable third component; a worm gearset having a worm gear fixed to said third component of said gear reduct

1. A transfer case comprising:an input shaft; an output shaft; a gear reduction unit having a first component driven by said input shaft; a second component driving said output shaft, and a rotatable third component; a worm gearset having a worm gear fixed to said third component of said gear reduction unit, and a worm meshed with said worm gear; and a variable speed motor for driving said worm so as to control the rotary speed of said third component relative to said input shaft for varying the speed ratio between said input shaft and said output shaft.