Pallet truck

1. A pallet truck, comprising:

a front frame having at least one fork and being connected to a drive unit through a lift cylinder;

an operator handle connected to the drive unit;

a plug-in battery assembly, a hydraulic supply system and a plug-in controller assembly connected to the front frame;

wherein the plug-in battery assembly further comprises a power source in a battery box, and a battery base, with the battery base being fixed to the front frame and the battery box being configured to plug-in and pull-out from the battery base;

wherein the front frame includes walls that extend vertically and define an upper opening, with the battery box being movable directly vertically through the upper opening and along the walls that extend vertically;

wherein the battery box further comprises a battery top and a battery bottom that are connected to a battery sidewall, and the power source is fixed to the battery bottom and is enclosed by the battery box;

wherein the battery box further comprises a battery cable female plug-in header and a battery signal line female plug-in header and the battery base further comprises a battery cable male plug-in header and a battery signal line male plug-in header;

wherein the battery bottom of the battery box further comprises an upward raised hollow guide column to which the battery cable female plug-in header and battery signal line female plug-in header are connected, and the battery base further comprises an upward raised guide block to which the battery cable male plug-in header and battery signal line male plug-in header are connected; and

wherein the upward raised hollow guide column on the battery bottom of the battery box has a height and the upward raised guide block on the battery base has a height that is substantially the same as the height of the upward raised hollow guide column, and wherein the battery sidewall has a height and the height of the upward raised hollow guide column on the battery bottom of the battery box is greater than two-thirds of the height of the battery sidewall.

2. The pallet truck in accordance with claim 1 , wherein on the front frame the plug-in battery assembly is located to one side of the lift cylinder and the hydraulic supply system and plug-in controller are located to the opposite side of the lift cylinder.

3. The pallet truck in accordance with claim 1 , wherein the power source is a lithium battery.

4. The pallet truck in accordance with claim 1 , wherein when the battery box is plugged into the battery base, the upward raised hollow guide column of the battery box receives the upward raised guide block of the battery base and the battery cable male plug-in header and battery signal line male plug-in header are connected to the respective battery cable female plug-in header and battery signal line female plug-in header.

5. The pallet truck in accordance with claim 1 , wherein the upward raised hollow guide column is located at a corner of the battery bottom of the battery box.

6. The pallet truck in accordance with claim 1 , wherein a first battery plug-in bracket is fixed to the upper end of the upward raised hollow guide column and the battery cable female plug-in header and battery signal line female plug-in header are fixed to the first battery plug-in bracket.

7. The pallet truck in accordance with claim 6 , wherein a second battery plug-in bracket is fixed to the upper end of the upward raised guide post on the battery base and the battery cable male plug-in header and battery signal line male plug-in header are fixed to the second battery plug-in bracket.

8. The pallet truck in accordance with claim 7 , wherein the second battery plug-in bracket further comprises a clamp that engages and releasably retains the first battery plug-in bracket when the battery box is plugged into the battery base.

9. The pallet truck in accordance with claim 1 , wherein a battery cable pin assembly and battery signal line pin assembly are fixed to the battery cable female plug-in header and battery signal line female plug-in header, respectively, and wherein a battery cable plug-in pin assembly and battery signal line plug-in pin assembly are fixed to the battery cable male plug-in header and battery signal line male plug-in header, respectively.

10. The pallet truck in accordance with claim 9 , wherein when the battery box is plugged into the battery base, the battery cable female plug-in header and its battery cable pin assembly receive and are connected to the battery cable male plug-in header and its battery cable plug-in pin assembly, and the battery signal line female plug-in header and its battery signal line pin assembly receive and are connected to and the battery signal line male plug-in header and its battery signal line plug-in pin assembly.

11. The pallet truck in accordance with claim 1 , wherein the battery box further comprises a battery top and a handle, switch and lamp are connected to the battery top.

12. The pallet truck in accordance with claim 1 , wherein the battery box further comprises a battery bottom and a battery management system module is connected to the battery bottom and enclosed by the battery box.

13. The pallet truck in accordance with claim 1 , further comprising,

a rear frame;

two mounting plates fixed to the rear frame, extending inward and connected to opposed sides of the drive unit;

two caster wheel assemblies connected to the respective two mounting plates;

wherein each caster wheel assembly further comprises a fixing plate at an upper end of the caster wheel assembly and each mounting plate further comprises an opening therein;

wherein a lower face of the fixing plate at the upper end of each caster wheel assembly is fixed to an upper face of the respective mounting plate proximate the opening.

14. The pallet truck in accordance with claim 13 , wherein each mounting plate fixed to the rear frame extends inward and includes an upward extending connecting side plate that is connected to the drive unit; and

the two mounting plates having openings therein and respective lower surfaces of the fixing plates of the two caster wheels engage respective upper surfaces of the two mounting plates, such that the caster wheel assemblies mount from above to the respective mounting plates.

15. A pallet truck, comprising:

a front frame having at least one fork and being connected to a drive unit through a lift cylinder;

a plug-in battery assembly, a hydraulic supply system and a plug-in controller assembly connected to the front frame;

an operator handle connected to the drive unit;

wherein the plug-in controller assembly further comprises a controller box, a control unit and a controller base;

the controller base being connected to the front frame of the pallet truck;

the controller box enclosing the control unit;

a lower end of the controller box having a receptacle and providing a controller cable plug-in header and a controller signal line plug-in header;

the controller base having a raised socket and providing a controller cable plug-in header and a controller signal line plug-in header; and

wherein when the controller box is plugged-into the controller base, the receptacle of the controller box receives the raised socket of the controller base and the controller cable plug-in header and the controller signal line plug-in header in the receptacle of the controller box engage and connect to the respective controller cable plug-in header and the controller signal line plug-in header in the raised socket of the controller base.

16. The pallet truck in accordance with claim 15 , wherein the controller box further comprises a back cover connected to a front cover, and the control unit is connected to the back cover, and wherein a controller plug-in bracket is located at an internal top of the receptacle.

17. The pallet truck in accordance with claim 16 , wherein the controller plug-in bracket is connected to the back cover and to the front cover of the controller box, and the controller base further comprises a clamp that engages and releasably retains the controller plug-in bracket in the receptacle of the controller box when the controller box is plugged into the controller base.