| 摘要 |
<p>A lift truck (10) has a push frame (22) extensible at a predetermined speed by a hydraulic cylinder (64) in a hydraulic circuit containing a hydraulically controlled synchronising switch (78) and an adjustable hydraulic flow control valve (72). The synchronising switch (78) operates automatically during extension of the push frame (22) to set a control circuit of the lift truck drive motor (32) such that the lift truck is caused simultaneously to be driven rearwards at a predetermined reverse speed equal to the speed of extension of the push frame (22) so as to deposit a load (20) in a predertermined position. A manually operable override switch (82) permits independent operation of the push frame drive and lift truck motor drive when necessary. Other automatic override switches (84, 136, 138) inhibit the effect of the synchronising switch (78) and prevent reverse lift truck movement in certain circumstances. The additional control apparatus can be fitted as an accessory to existing lift trucks. </p> |
