초록 ▼

A materials handling vehicle is provided comprising: a power unit; a work assembly coupled to the power unit comprising a first auxiliary device; and a fluid supply system. The fluid supply system may comprise: pump structure for supplying a fluid; a first manifold apparatus located on the power uni

A materials handling vehicle is provided comprising: a power unit; a work assembly coupled to the power unit comprising a first auxiliary device; and a fluid supply system. The fluid supply system may comprise: pump structure for supplying a fluid; a first manifold apparatus located on the power unit; a second manifold apparatus located on the work assembly; and fluid supply line structure coupled between the first and second manifolds. The first manifold may receive fluid from the pump structure and comprise valve structure for maintaining fluid pressure at an output port of the first manifold apparatus at a commanded pressure substantially equal to or greater than an operating pressure of the first auxiliary device.

대표청구항 ▼

1. A materials handling vehicle comprising: a power unit;a work assembly coupled to said power unit comprising a first auxiliary device; anda fluid supply system comprising: pump structure for supplying a fluid;a first manifold apparatus located on said power unit and receiving fluid from said pump

1. A materials handling vehicle comprising: a power unit;a work assembly coupled to said power unit comprising a first auxiliary device; anda fluid supply system comprising: pump structure for supplying a fluid;a first manifold apparatus located on said power unit and receiving fluid from said pump structure, said first manifold apparatus comprising valve structure for maintaining fluid pressure at an output port of said first manifold apparatus at a commanded pressure substantially equal to or greater than an operating pressure of said first auxiliary device;a second manifold apparatus located on said work assembly;fluid supply line structure coupled between said first and second manifolds;an electronic controller coupled to said valve structure for generating a control signal to said valve structure causing said valve structure to maintain fluid pressure at said output port at said commanded pressure, said control signal being generated by said controller in response to receiving an operator-generated command to actuate said first auxiliary device;said work assembly further comprises a mast assembly and a fork carriage apparatus, said fork carriage apparatus comprises: a fork carriage mechanism; a pair of forks mounted to said fork carriage mechanism for movement with said fork carriage mechanism; anda movement mechanism associated with said fork carriage mechanism to effect movement of at least a portion of said fork carriage mechanism and said forks, wherein said movement mechanism defines said first auxiliary device. 2. The materials handling vehicle as set out in claim 1, further comprising a second auxiliary device, said first and second auxiliary devices having first and second required operating pressures, respectively, said first operating pressure is different from said second operating pressure, and said valve structure maintains fluid pressure at said output port equal to or greater than said first operating pressure during operation of said first auxiliary device and said second operating pressure during operation of said second auxiliary device. 3. The materials handling vehicle as set out in claim 2, wherein said valve structure comprises an electronically controlled proportional pressure reducing and relieving valve, wherein said proportional valve is controlled to maintain fluid pressure at said output port equal to or greater than said first required operating pressure when said first auxiliary device is selected for operation and said second required operating pressure when said second auxiliary device is selected for operation. 4. The materials handling vehicle as set out in claim 1, wherein said fork carriage apparatus further comprises: a mast carriage assembly adapted to vertically move along said mast assembly;said movement mechanism comprises a reach mechanism coupled between said mast carriage assembly and said fork carriage mechanism to effect movement of said fork carriage mechanism and said forks toward and away from said mast carriage assembly, wherein said reach mechanism defines said first auxiliary device. 5. The materials handling vehicle as set out in claim 4, wherein said fork carriage mechanism comprises: a carriage support structure coupled to said reach mechanism;a fork carriage frame coupled to said carriage support structure, said forks being mounted to said fork carriage frame; anda side-shift mechanism coupled to said carriage support structure and said fork carriage frame for effecting lateral movement of said fork carriage frame and said forks relative to said carriage support structure, wherein said side-shift mechanism defines a further auxiliary device. 6. The materials handling vehicle as set out in claim 5, wherein said fork carriage mechanism further comprises a tilt device coupled to said carriage support structure for effecting pivotable movement of said fork carriage frame relative to said carriage support structure, wherein said tilt device defines another auxiliary device. 7. The materials handling vehicle as set out in claim 1, wherein said second manifold apparatus comprises a first electronically controlled flow-directing solenoid valve for directing fluid flow to one of auxiliary device extend lines or auxiliary device retract lines. 8. The materials handling vehicle as set out in claim 7, wherein said second manifold apparatus further comprises a first electronically controlled ON/OFF solenoid valve for controlling fluid flow to a first auxiliary device. 9. The materials handling vehicle as set out in claim 8, wherein said second manifold apparatus further comprises a second electronically controlled ON/OFF solenoid valve for controlling fluid flow to a second auxiliary device and a third electronically controlled ON/OFF solenoid valve for controlling fluid flow to a third auxiliary device. 10. The materials handling vehicle as set out in claim 8, wherein said second manifold apparatus further comprises: a first proportional valve varied based on operator input to control the rate of extension of at least one reach cylinder of a reach mechanism forming part of said work assembly; anda second proportional valve varied based on operator input to control the rate of retraction of at least one reach cylinder of said reach mechanism. 11. The materials handling vehicle as set out in claim 10, wherein said reach mechanism further comprises first and second inner and outer arms associated with a mast carriage assembly and said fork carriage mechanism. 12. The materials handling vehicle as set out in claim 11, further comprising a sensor for sensing relative movement between said reach mechanism and said mast carriage assembly. 13. The materials handling vehicle as set out in claim 12, wherein said sensor comprises an encoder. 14. The materials handling vehicle as set out in claim 13, wherein the controller limits a maximum speed of first ends of said first and second outer arms at an end of a reach mechanism extension stroke by limiting an amount said first proportional valve is opened. 15. The materials handling vehicle as set out in claim 1, wherein said valve structure modulates flow so as to maintain the pressure at the output port at the commanded pressure. 16. The materials handling vehicle as set out in claim 1, wherein said valve structure reduces fluid flow when the pressure at the output port exceeds the commanded pressure. 17. The materials handling vehicle as set out in claim 1, wherein said fork carriage mechanism comprises: a carriage support structure;a fork carriage frame coupled to said carriage support structure, said forks being mounted to said fork carriage frame; anda side-shift mechanism coupled to said carriage support structure and said fork carriage frame for effecting lateral movement of said fork carriage frame and said forks relative to said carriage support structure, wherein said side-shift mechanism defines said auxiliary device. 18. The materials handling vehicle as set out in claim 1, wherein said fork carriage mechanism further comprises a tilt device coupled to a carriage support structure for effecting pivotable movement of a fork carriage frame relative to said carriage support structure, wherein said tilt device defines said auxiliary device. 19. A materials handling vehicle comprising: a power unit;a work assembly coupled to said power unit comprising a first auxiliary device; anda fluid supply system comprising: pump structure for supplying a fluid;a first manifold apparatus located on said power unit and receiving fluid from said pump structure, said first manifold apparatus comprising valve structure for maintaining fluid pressure at an output port of said first manifold apparatus at a commanded pressure substantially equal to or greater than an operating pressure of said first auxiliary device;a second manifold apparatus located on said work assembly and comprising a first proportional valve controlled based on operator input to control the rate of movement of said first auxiliary device in a first direction and a second proportional valve controlled based on operator input to control the rate of movement of said first auxiliary device in a second direction;fluid supply line structure coupled between said first and second manifolds; andan electronic controller coupled to said valve structure for generating a control signal to said valve structure causing said valve structure to maintain fluid pressure at said output port at said commanded pressure, said control signal being generated by said controller in response to receiving an operator-generated command to actuate said first auxiliary device.