Wheel stopping device

Claim 1

In a wheel stopping device including first and second wheel engaging shafts (27, 27a) movable in parallel to axles (12, 12a) of first and second wheels (11, 11a) disposed at two different locations, and first and second ribs (46) projecting from lateral surfaces of said first and second wheels (11, 11a), wherein, when said first engaging shaft (27) is moved toward and engages said first rib (46) for locking said first wheel against rotation, in operative association therewith, said second engaging shaft (27a) is also moved toward and engages said second rib for locking said second wheel also against rotation, and wherein said first and second engaging shafts also return together to their original state for permitting wheel rotation, the improvement comprising first and second L-levers (28, 28a), said first and second engaging shafts (27, 27a) being connected to one of the respective ends of said first and second L-levers (28, 28a), first and second wheel attaching members (13, 13a) for attaching said first and second wheels (11, 11a) and for rotatably supporting said L-levers, respectively, an operating member (25) movably attached to said first wheel attaching member (13) so that said operating member abuts against the other end of said first L-lever (28), a first spring (44) arranged for urging said first L-lever (28) against said operating member (25), whereby said first engaging shaft (27) is moved toward and away from said first rib (46) in response to movement of said operating member (25) causing rotation of said first L-lever (28), a wire (26) connected between said operating member (25) and said second L-lever (28a) for transmitting movement of said operating member (25) to the second L-lever (28a) for rotating said second L-lever (28a) in synchronism with said first engaging shaft (27), whereby said second engaging shaft (27a) is moved toward and away from said second rib, a second spring (44a) arranged for cooperation with said second L-lever (28a) for urging said second L-lever to rotate in the direction in which the second L-lever (28a) imparts tension to said wire (26) in response to movement of said operating member (25) in a direction for rotating said first L-lever (28) against the resilience of said first spring (44), whereby said first engaging shaft (27) is moved away from said first rib (46) while the force transmitted through said wire (26) rotates said second L-lever (28a) against the resilience of said second spring (44a) so as to move said second engaging shaft (27a) away from said second rib for permitting wheel rotation, and locking members (36, 45) operatively arranged for cooperation with said first and second springs (44, 44a) for locking said operating member (25) against moving relative to said first wheel attaching member (13) for maintaining a wheel rotation permitting state, and means for cancelling the locking by said locking members (36, 45) whereby said first and second springs (44, 44a) cause said first and second engaging shafts (27, 27a) to move toward said first and second ribs (46) for again establishing a wheel locking state, and wherein said operating member (25) comprises guide shaft means (38) extending laterally away from said operating member, guide holes (34) laterally extending through said operating member, and a guide member (39) operatively held by said guide holes (34) for guiding said wire (26), said first wheel attaching member (13) having guide cuts (43) for operatively receiving said guide shaft means (38), whereby said operating member (25) is movable relative to said first wheel attaching member (13) through a displacement range defined by said guide holes (34) holding said guide member (39) for said wire and by said guide cuts (43) in which said guide shaft means (38) is movable.