Electrically driven track wheels for tracked vehicles

Abstract

An electrically driven wheel for a tracked vehicle which includes a driving track wheel with built in cogs and a brushless DC motor having a mounting shaft to connect the wheels to the tracked vehicle. The brushless DC motor is coupled within the driving track wheel to develop rotational torque for rotating the driving track wheel and includes a drum, a bank of pole assemblies connected between the drum and the stationary mounting shaft, and electrical wiring for energizing the bank of pole assemblies. In an embodiment, the brushless DC motor includes permanent magnet high multiple pole motors. The electrically driven wheels are part of a drive system for the tracked vehicle. The drive system includes a track module frame, at least two flexible tracks coupled with the electrically driven track wheels, and a controller for controlling the electrically driven track wheels in response to a driver command.

Description

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a tracked vehicle using the electrically driven wheels according to the present invention.

FIG. 2 is a perspective view showing the frame with suspension system and electrically driven wheels of FIG. 1.

FIG. 3 is an exploded view of the wheels shown in FIG. 2.

FIG. 4 is a side view of the track, driving track wheels and parallel track module frame connected with the tracked vehicle chassis.

FIGS. 5 a and 5b show three-quarter angle perspective views of the inside and outside end plates of the electrically driven wheel showing the motor mounting shaft extending through the center

FIGS. 5 c and 5d show left and right end views of the brushless DC motor corresponding to the side views shown in FIGS. 5a and 5b, respectively.

FIG. 5 e shows a top view of the wheel.

FIG. 6 is an enlarged perspective side view of the brushless DC motor shown in FIGS. 5a through 5e.

FIGS. 7 a and 7b are cross sectional side views of the brushless DC motor shown in FIG. 6 sliced perpendicular to the wheel mounting shaft for a double and a single pair stator.

FIG. 8 is another cross sectional perspective side view of the brushless DC motor shown in FIG. 6 sliced parallel to the wheel mounting shaft.

FIG. 9 is an exploded view showing the parts of the brushless DC motor shown in FIG. 7a.

FIG. 10 is a schematic block diagram of the motor and control system used with the vehicle shown in FIG. 1.

FIGS. 11 a and 11b are rear and side views, respectively, of an example of a pilot control stick connected with the control system.

FIG. 11 c is a schematic diagram of control stick connected with the control system.

FIG. 12 shows the Low Speed/High Torque configuration of the control system.

FIG. 13 shows the High Speed/Half Torque configuration of the control system.

Claims

1. An electrically driven wheel for a tracked vehicle comprising: a driving track wheel having built in cogs on an outer surface for driving a track;a brushless DC motor having a stationary mounting shaft running through the brushless DC motor for connecting the electrically driven wheel to a frame of the tracked vehicle, wherein the brushless DC motor is coupled within the driving track wheel to develop rotational torque for rotating the driving track wheel; andtwo end plates covering each end of the driving track wheel enclosing the brushless DC motor therein, wherein the driving track wheel directly transmits thrust loads directly to the mounting shaft.

2. The tracked vehicle of claim 1, wherein the stationary mounting shaft comprises: hollow portion within the stationary mounting shaft for routing electrical wiring and coolant lines to operate the brushless DC motor through stationary mounting shaft to allow brushless DC motor to be sealed against an environment and to prevent oil spills or water contamination.

3. The electrically driven wheel of claim 1, wherein the brushless DC motor further comprises: a drum having an interior and an exterior surface;a bank of pole assemblies connected between the interior surface of the drum and the stationary mounting shaft; andelectrical wiring for energizing the bank of pole assemblies, wherein the electrical wiring is routed through a hollow portion of the stationary mounting shaft between said brushless DC motor and a tracked vehicle controller.

4. The electrically driven wheel of claim 1, further comprising: permanent magnet high multiple pole motors for precise track control and synchronization.

5. The electrically driven wheel of claim 3, wherein the bank of pole assemblies comprises: at least three sets of stator windings mounted to the stationary mounting shaft in a three phase arrangement; andat least three rows of magnets connected with the at least three sets of stator windings, each row arranged in a disc to turn with the drum of the brushless DC motor.

6. The electrically driven wheel of claim 5, wherein the at least three sets of stator windings further comprise: an offset difference between of the at least three stator windings of 0.0, −6.6 and −13.3 degrees for a 36 pole motor.

7. The electrically driven wheel of claim 5, wherein the at least three sets of stator windings further comprise: an offset difference between of the at least three stator windings of 0.0, −5.0 and −10.0 degrees for a 48 pole motor.

8. The electrically driven wheel of claim 3, wherein the bank of pole assemblies comprises: special permanent magnet material and mounting to permit operations as low as −50 degrees C. and as high as +50 degrees C.

9. The electrically driven wheel of claim 1, wherein the brushless DC motor comprises: permanent magnet electric motor drive which allows efficiency over approximately 95% without traditional heat losses to clutches, gear boxes, differentials, hydraulics, etc., for less heat loss to affect environment by melting frozen tundra, and motor temperature stays very close to ambient.

10. The tracked vehicle of claim 1, wherein said brushless DC motor is sealed with said end plates and pressurized with inert gas for water protection.

11. The tracked vehicle of claim 1, further comprising: a liquid coolant for cooling and heating said brushless DC motor.

12. A drive system for a tracked vehicle comprising: a track module frame for connecting the drive system with a chassis of the tracked vehicle;at least two electrically driven track wheels connected with the track module frame;at least two flexible tracks each coupled with two of the at least two electrically driven track wheels, wherein each of the at least two flexible tracks travel around the corresponding electrically driven track wheel; anda controller for controlling the at least two electrically driven track wheels in response to a driver command.

13. The system of claim 12, wherein each one of the at least two electrically driven track wheels comprises: a driving track wheel having plural built in cogs on an outer surface for driving the flexible track; andan electrically driven motor having a stationary mounting shaft inside the driving track wheel to develop rotational torque, wherein the at least two electrically driven track wheels distribute the stress in the flexible track to reduce environmental disturbance.

14. The system of claim 12, wherein each of the at least two flexible tracks comprise: plural track cogs on an inner surface of the flexible track to mate with the plural built in cogs on the outer surface of the driving track wheel.

15. The system of claim 13, wherein the electrically driven motor comprises: a hollow shaft within the stationary mounting shaft to route electrical wiring and coolant lines; andend covers enclosing said electrically driven motor within the driving track wheel, wherein a thrust load is transmitted to the stationary mounting shaft.

16. The system of claim 13, wherein the electrically driven motor comprises: permanent magnet high multiple pole motors for precise track control and synchronization.

17. The system of claim 13, wherein each of the at least two electrically driven wheels comprises: permanent magnet electric motor drive which allows efficiency over approximately 95% without traditional heat losses to clutches, gear boxes, differentials and hydraulics to maintain a motor temperature of approximately ambient.

18. The system of claim 12, wherein the controller comprises: an interface for communicating with a vehicle control electronics;at least four sensors for sensing a position of the at least four electrically driven wheels; andat least four controllers each connected with one of the at least four sensors and a corresponding one of the left and right front and rear electrically driven wheels for energizing the left and right front and rear electrically driven motors in response to a command from the vehicle control electronics.

19. The system of claim 12, wherein said controller comprises: a control system for automatic protection against overload, over current, over speed, too tight turn at high speed and a top speed based on G-loads of rough terrain.

20. The system of claim 12, wherein each one of the at least two flexible tracks include full torque capability in a forward and a reverse direction.

21. The system of claim 12, wherein each of the at least two flexible tracks is selected from one of: low temperature flexibility rubber tracks and steel tracks.

22. A tracked vehicle, comprising: a track module frame;at least two electrically driven track wheels connected with the track module frame;at least two flexible tracks, one on each sides of the track module frame and being rotated by the at least two electrically driven track wheels, wherein the at least two flexible tracks have the ability to resiliently track uneven surfaces to increase track life and minimizing disturbance to the terrain; anda suspension system for connecting the track module frame to a chassis of the tracked vehicle, wherein shock encountered by the track module frame are not transmitted to the vehicle chassis.

23. The system of claim 21, further comprising: independent control for vertical movement, tilting (angular) movement and torsional movement.

24. The tracked vehicle of claim 21, further comprising: an adjustable height control for adjusting a ground clearance of the track vehicle to compensate for different terrain slopes to provide a smoother, safer ride, with bump absorption, improved stability, and a faster allowable speed of navigation over uneven surfaces.

25. The tracked vehicle of claim 21, wherein each one of the at lest two track wheels comprise: a driving track wheel having built in cogs for driving one of the at least two tracks; andan individual electrical motor coupled within the driving track wheel to develop rotational torque for rotating the driving track wheel.

26. The tracked vehicle of claim 24, wherein each of the at least two flexible tracks comprise: plural belt cogs on an interior surface of the flexible track to mate with the built in cogs on the driving track wheel, wherein the driving track wheel has over approximately 180 degrees of contact between the built in cogs and the matching plural belt cogs.

27. The tracked vehicle of claim 21, wherein each of the at least two track wheels comprise: an internal direct drive pulse modulated DC integral motor to provide twice the power available to the ground and the actual tensile stress on the at least two flexible tracks is more evenly distributed.

28. The tracked vehicle of claim 21, further comprising: a second track frame modules for driving at least one of a trailer and a second tracked vehicle forming a tracked trailer train.

29. The tracked vehicle of claim 21, wherein the track module frame comprises: at least two interchangeable self contained track frame modules.