Crawler traveling apparatus
A crawler traveling apparatus includes a rubber crawler belt having a plurality of driving projections formed with a predetermined peripheral pitch on an inner peripheral face of the belt, a drive wheel rotatable when engaged with the driving projections of the crawler belt for driving the belt, and a plurality of free wheels rotatable for laterally guiding the driving projections under movement. Each driving projection has an upper half having a lateral face including an upper half lateral face portion and a lower half having a lower half lateral face portion, the upper half lateral face portion having an erect inclination angle smaller than an erect inclination angle of the lower half lateral face portion. Each free wheel has an inner lateral face opposed to the driving projection, the inner lateral face having an inclined guide face having an inclination parallel to the lower half lateral face portion of the driving projection. The inclined guide face has a height L 3 shorter than a height L 1 of the lower half lateral face portion when an inner peripheral face of the crawler belt is placed under proper contact with an outer peripheral face of the free wheel.
1. A crawler traveling apparatus comprising:
a rubber crawler belt having a plurality of driving projections formed with a predetermined peripheral pitch on an inner peripheral face of the belt;
a drive wheel rotatable when engaged with the driving projections of the crawler belt for driving the belt; and
a plurality of free wheels rotatable for laterally guiding the driving projections under movement;
wherein said each driving projection has an upper half having an upper half lateral face portion and a lower half having a lower half lateral face portion, the upper half lateral face portion having an erect inclination angle smaller than an erect inclination angle of the lower half lateral face portion;
said each free wheel has an inner lateral face opposed to the driving projection, said inner lateral face having an inclined guide face having an inclination parallel to said lower half lateral face portion of the driving projection; and
said inclined guide face has a height L 3 shorter than a height L 1 of said lower half lateral face portion when an inner peripheral face of the crawler belt is placed under proper contact with an outer peripheral face of the free wheel.
2. The crawler traveling apparatus as defined in claim 1 , wherein the free wheels include a pilot wheel, a ground free wheel and a guide wheel; and an inner width W( 3 ) of the drive wheel, an inner width W( 6 ) of the ground free wheel and an inner width W( 7 ) of the guide wheel have a relationship of:
W( 3 )>W( 6 )>W( 7 ).
3. The crawler traveling apparatus as defined in claim 2 , wherein said pilot wheel includes a pair of front and rear pilot wheels, and inner widths W( 4 ) and W( 5 ) of these front and rear pilot wheels which constitute the rest of the free wheels, are substantially equal to or slightly greater than the inner width W( 7 ) of the guide wheel.