Energy Storage on an Elevated Platform and Transfer Method

• US 20120145485A1
• Filed: 06/15/2011
• Published: 06/14/2012
• Est. Priority Date: 03/01/2010
• Status: Active Grant

• Current Assignee: The Raymond Corporation (Toyota Motor Corporation)
• Original Assignee: The Raymond Corporation (Toyota Motor Corporation)
• Inventors: McCabe, Paul P., Radler, Daniel G.
• Granted Patent: US 8,869,944 B2
• Time in Patent Office: Days
• US Class Current: 187/226
• CPC Class Codes: B66F 9/24 Electrical devices or systems
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/025 using non-contact coupling, e.g. inductive, capacitive
• CPC Class Codes: H02J 7/342 The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging with circuits for polarity protection H02J7/0034
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices

Abstract

A lift truck includes a secondary rechargeable energy storage device on a vertically movable platform that is separate from a primary rechargeable energy storage device on the lift truck'"'"'s main tractor unit. Wires or hoses for transfer of power or controls between the main tractor unit and the platform are reduced or eliminated. The quantity of energy stored in the secondary rechargeable energy storage device is sufficient to power platform electrical loads for a predetermined amount of time until the platform is lowered. When the platform is lowered, the secondary rechargeable energy storage device is recharged by the primary energy storage device.

Claims

1. A lift truck comprising:

a tractor unit;

a primary energy storage device disposed on the tractor unit, the primary energy storage device configured to provide operating power to the tractor unit;

a vertically extendable mast mounted relative to the tractor unit, the mast including a fixed base and an extendable mast section;

a vertically movable platform coupled to the extendable mast section, the platform being vertically movable with the extendable mast section between an upper position and a lower position; and

a rechargeable secondary energy storage device disposed within a space defined by a width of the extendable mast section, the rechargeable secondary energy storage device being rechargeable upon moving the platform toward the lower position.

2. The lift truck according to claim 1:

further including an energy transfer coupling, the energy transfer coupling configured to transfer energy from the primary energy storage device to the rechargeable secondary energy storage device to recharge the rechargeable secondary energy storage device.

3. The lift truck according to claim 2:

wherein the primary energy storage device comprises a rechargeable device.

4. The lift truck according to claim 3:

wherein the energy transfer coupling is configured to transfer energy from the secondary energy storage device to the primary energy storage device.

5. The lift truck according to claim 2:

wherein the energy transfer coupling comprises at least one of a physical coupling and an inductive coupling.

6. The lift truck according to claim 1:

further including a operator station, the operator station including controls configured for use by the operator to control the tractor unit and the platform.

7. The lift truck according to claim 1:

wherein the tractor unit includes a first wireless communication unit and the platform includes a second wireless communication unit, the first and second wireless communication units configured to provide a wireless communication link between the tractor unit and the platform.

8. The lift truck according to claim 7:

further including an operator station, the operator station including controls configured for use by the operator to control the tractor unit and the platform via the first and second wireless communications units.

9. The lift truck according to claim 1:

wherein the rechargeable secondary energy storage device further includes at least one capacitor, the at least one capacitor configured to accept an energy transfer from the primary energy storage device.

10. The lift truck according to claim 9:

wherein the rechargeable secondary energy storage device further includes a DC-to-DC voltage converter, the voltage converter configured to convert a voltage from the at least one capacitor to a recharge voltage to recharge the rechargeable secondary energy storage device.

11. The lift truck according to claim 2:

wherein the energy transfer coupling comprises a primary side coupling and a secondary side coupling, with the secondary side coupling being disposed within the space defined by the width of the extendable mast section and the primary side coupling being disposed on the tractor unit.

12. The lift truck according to claim 1:

wherein the space is defined by the width and a thickness of the extendable mast section.

13. The lift truck according to claim 1:

wherein the platform supports at least one of an operator and a load.

14. A lift truck comprising:

a tractor unit;

a rechargeable primary energy storage device disposed on the tractor unit,

a vertically movable platform movably coupled to the tractor unit, the platform being vertically movable between an upper position and a lower position and including an operator station;

a rechargeable secondary energy storage device disposed within the operator station; and

an energy transfer coupling, the energy transfer coupling configured to transfer energy from the rechargeable primary energy storage device on the tractor unit to the rechargeable secondary energy storage device on the platform to recharge the rechargeable secondary energy storage device.

15. The lift truck according to claim 14:

wherein the energy transfer coupling further includes at least one capacitor, the at least one capacitor configured to accept an energy transfer from the rechargeable primary energy storage device; and

a voltage converter, the voltage converter configured to convert a voltage from the at least one capacitor to a recharge voltage to recharge the rechargeable secondary energy storage device.

16. The lift truck according to claim 14:

further including a transfer coupling sense circuit configured to sense a voltage potential difference between the primary energy storage device and the rechargeable secondary energy storage device.

17. The lift truck according to claim 14:

further including a vertically extendable mast mounted relative to the tractor unit, the mast including a fixed base and an extendable mast section; and

the platform coupled to the extendable mast section, the platform being vertically movable with the extendable mast section between the upper position and the lower position.

18. The lift truck according to claim 14:

wherein the operator station includes controls configured for use by the operator to control the tractor unit and the platform.

19. A method comprising:

providing a lift truck, the lift truck comprising

a tractor unit;

a primary energy storage device disposed on the tractor unit;

a vertically extendable mast mounted relative to the tractor unit, the mast including a fixed base and an extendable mast section;

a vertically movable platform coupled to the extendable mast section, the platform being vertically movable with the extendable mast section between an upper position and a lower recharge position; and

a rechargeable secondary energy storage device disposed within a space defined by a width of the extendable mast section;

lowering the vertically extendable mast from the upper position to the lower recharge position; and

recharging the rechargeable secondary energy storage device by transferring energy from the primary energy storage device to the rechargeable secondary energy storage device when the platform is in the lower recharge position.

20. The method according to claim 19:

further including sensing for a voltage potential difference between the primary energy storage device and the rechargeable secondary energy storage device, and recharging only when the voltage potential difference is sensed.

21. The method according to claim 19:

wherein transferring energy from the primary energy storage device to the rechargeable secondary energy storage device occurs automatically when the platform in the lower recharge position.

22. The method according to claim 19:

further including using the potential energy generated from lowering the platform for recharging the rechargeable secondary energy storage device.

23. The method according to claim 19:

further including using wireless communications to operate the lift truck.

24. The method according to claim 19:

further including operating the tractor unit and the platform using energy supplied by the rechargeable secondary energy storage device when the primary energy storage device is non-operational.

25. The method according to claim 19:

wherein the rechargeable secondary energy storage device comprises at least one capacitor, a DC-to-DC voltage converter, and at least one battery.