WO2018126298A1

WO2018126298A1 - "dual driven wheels load mover"

Info

Publication number: WO2018126298A1
Application number: PCT/AU2018/050005
Authority: WO
Inventors: Gregory NEWELL
Original assignee: Newell Gregory
Priority date: 2017-01-07
Filing date: 2018-01-08
Publication date: 2018-07-12

Abstract

The present application describes a novel type of powered pallet jack or load mover of similar form where there are two independently driven wheels instead of one. This format provides the dual capabilities of operating the device with manual turning by an operator turning the handle tiller, or, with the addition of appropriate automation componentry, operating the device autonomously without an operator present – turning by driving one wheel faster or slower than the other. A simple power steering feature can also be included very inexpensively, making use of the device's differential drive design.

Description

DESCRIPTION "DUAL DRIVEN WHEELS LOAD MOVER"

TECHNICAL FIELD

The present invention relates to a powered pallet jack or cart mover that allows for operator controlled or operatorless (automated/robotic) control of the load moving device. Its design allows both modes to be very functional in the same compact and low cost machine while also allowing quick switching between those modes as needed.

BACKGROUND ART

The manual pallet jack was invented in the 1930's and the first units became commercially available soon thereafter. Pallet jacks have been modified for purposes other than for lifting and moving pallets such as with platforms or other attachments and including more recently hitching connections that allow it to connect with and move carts for example. A typical jack includes a hydraulic jacking system that supports a frame carrying a pair of forwardly extending forks or other adaptation. The lifting mechanism includes a lift cylinder with an upward pushing lifting rod that connect directly and or through linkages to the frame plus a pump cylinder for providing pressurized hydraulic fluid to the lift cylinder.

Other pallet jack assemblies and related prior art lift devices are shown in the following U.S. patents:

2,049,335 1936-Jul-28 Stephens 2,309,138 1943-Jan-26 Quayle 2,461,212 1949-Feb-08 Hanna 3,462,167 1969-Aug-19 Rateau 2,488,521 1949-Nov-22 Barrett 2,993,703 1961-Jul-25 Paradise 3,118,107 1965-Jun-08 Quale 3,119,627 1964-Jan-28 Klumb 3,286,985 1949-Nov-22 Barrett 2,993,703 1961-Jul-25 Paradise 3,118,107 1965-Jun-08 Quale 3,119,627 1964-Jan-28 Klumb 3,286,985 1966-Nov-22 Edera 3,567,240 1971-Mar-02 Brassington 3,608,922 1971-Sep-28 Best et al 3,701,211 1972-Oct-31 Best 3,757,523 1973-Sep-ll Resuggan 3,775,027 1973-Nov-27 Craft 3,817,546 1974-Jun-18 Suguira 3,843,147 1974-Oct-22 Fredricson 3,940,338 1976-Feb-24 Btyntse, et al. 4,497,501 1985-Feb-05 Kedem

While sit-on powered forklifts had been invented near the turn of the 19^th century, being adaptations of small vehicular trucks, manual pallet jacks which were developed later did not lend themselves to being converted to powered locomotion due to the size and weight of the engines available at the time. As a result, pallet jacks with powered locomotion did not become available until the middle of the century as lead acid batteries and electric motors became more available.

In powered pallet moving devices, such powered pallet jacks are generally referred to as "walkies" as you walk behind them, vs. "riders" that have a platform to stand on and fork trucks that are typically sit-down units.

US patent US8752657 provides of an power assembly that upgrades a manual pallet jack to a powered pallet jack with an attachable drive unit. This invention takes that a significant step beyond, with a different design that includes the possibility of adding additional power and functionality in addition to automation to such a material handling device.

Autonomously / robotically controlled movers that engage with a wheeled load, such as a cart or trolley, or unwheeled load, such as a skid or pallet, are a relatively new category of product. Their popularity has been increasing in recent years, the driving force behind this automation being seen throughout the manufacturing, warehousing and logistics industries due to pressure to increase cycle times, reduce labor content, reduce errors, etc. The rate of automation has also been made possible by the many recent advancements in motor technologies, navigation sensor technologies and of course the continuing advancements in computer technology generally.

A problem for many customers is that usually automated systems are an "all or nothing" option. Many companies exist where they have interest to automate some repetitive material handling tasks, but do not want to incur the expense of such a massive investment to fully automate their facility, particularly when many tasks cannot be cost-effectively or efficiently automated and having an operator controlling the device and making the decisions is a better alternative.

DISCLOSURE OF INVENTION

The present invention has been designed to address the above described need to have a single device that can be used as a manual, powered or autonomous load moving device. This device achieves that goal, being capable of operating in multiple modes and to be changed between modes very quickly and easily - with the push of a button.

Firstly, it can be operated in manual mode, the turning and pulling/pushing the loaded device being by the operator's own exerted force.

Secondly, the device can be operated in powered mode, where turning (or optionally power- assisted turning) is by the operator but the motive power is provided by the powered drive system of the device so no force is required to push or pull the loaded device.

Thirdly, if the device is equipped with the necessary automation componentry, it can operate in an autonomous mode and perform a long distance or repetitive travel autonomously, so without the operator even being present.

While a number of features of the present invention are desirous to be included in the device configuration, certain features can potentially be excluded, such as power steering or autonomous operation, to reduce the cost and complexity of the machine. Such features can also be excluded from the initial purchase but included at a later time as a retrofit upgrade when the customer's budget allows or when that extra functionality is required.

Two versions of drive are illustrated. One is where each independent motor drives a support wheel via one or more sets of chains and sprockets or belts and pulleys.

The is a direct drive version or hub motor version, where each support wheel has the motor and any gearing that may be included mounted coaxially and within the support wheel.

Other drive configurations are possible to achieve the same essential goal, such as having each motor or motor-gearbox located adjacent to the support wheel it is driving and then the connection between them being geared or even a friction drive transfer method.

In this design, there are two motors or motor-gearboxes, each independently driving each support wheel which are in turn, mounted on a coaxial axle that passes through and perpendicular to the centered vertical axis of the support wheel and lifting assembly, about which the drive axle axis pivots. This is an unconventional way of providing drive to a pallet jack or similar device as having two wheels driven that are either side of the vertical axis that the turning system rotates about.

Conventional powered pallet trucks, or "walkies" as they ae commonly referred, typically have one drive wheel (that may be a hub motor) on the same center pivot as the rotating drive wheel/handle assembly. This does however mean that when turning, particularly when stationary or driving at slow speeds, there is frictional resistance to the turning. For example, if that driven wheel is 50mm wide, a 25mm long band on one side is dragged clock-wise and the other 25mm band is dragged in the opposite way when it rotates. This resistance is felt by the operator as he tries to turn the handle. So for this reason, many operators prefer manual pallet jacks in back-of-truck applications where there is a lot of maneuvering and not typically much travel distance needing to be covered (where the powered drive is a benefit).

With this invention, turning the handle (maneuvering) when stationary is as effortless as on a manual jack as the two drive wheels, offset from the center pivot axis, simply roll with almost no resistance (as the drive motors are not engaged) around that center pivot. There is no dragging involved and once the throttle is engaged, both wheels work together to move the loaded jack.

When driving however, the benefit switches and now the frictional drag from a center drive wheel is less than the powered resistance from the pair of offset driven support wheels.

When turning with a manual pallet jack, that has two offset wheels in a similar configuration, the inside support wheel can be easily retarded in its travel speed to compensate for the increased speed of the support wheel on the outside arc of the turn. With this invention configuration however where the wheels are powered, the driven wheel on the inside of the turn would resist such speed reduction as it is being powered to move the load.

There are however two means of addressing this issue.

The first is to have a drive program that delivers equal amps to rotate each wheel (when the throttle is depressed) but does not do anything to prevent a motor being overdriven - that is from rotating at a speed faster than at the speed at which it is being driven under whatever load it is bearing. This means that when driving a load and turning, the operator would effectively have a long lever (being the mast of the handle tiller) that would pull the outside wheel in the turn forward and "about" the inside wheel. (By comparison, with an unpowered manual jack, when the operator turns he pulls the outside wheel about the center pivot point). Although this method described, turning the outside wheel about the inside wheel, would require a noticeable amount of additional effort as compared to when running straight or as compared to operating a conventional centrally located drive wheel, it would not be so great as to be a significant problem and would be most noticeable with heavy loads, but barely noticeable with low or no loads. Sop an inconvenience, but not so great as to not be able to be overcome relatively easily by the operator.

The second is to have a means of measuring the force the operator exerts on the handle when he is turning it and instantly calibrating that measure to determine how much to adjust the relative speed of each driven wheel. So slightly increasing the speed of the wheel on the outside of the turn and reducing the speed of the wheel on the inside of the turn, all the time re-measuring the force at the handle to ensure it is being reduced. Considering the number of adjustments in amp delivery to a motor that are made every second in a brushless motor, it is very feasible to include such a feature so that the "disadvantage" of offset driven support wheels can be turned into an advantage, with a simple form of power steering now coming out of this system. In comparison, a simple single driven wheel has minimal friction when turning, but quite significant frictional drag when the powered jack is stationary.

Lastly, the big advantage of having two driven support wheels is that if the appropriate sensors, such as a Lidar laser or line following camera or magnetic sensor or other navigation hardware and software is added to the machine, this machine can switch quickly and easily to autonomous travel. So overall, this machine is unique due to its functional versatility, compactness, high power output and low manufacture cost.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the invention are described below with the reference to the following accompanying drawings:

Figure 1 is a back-side perspective view of a standard manual pallet jack.

Figure 2 is a back-side perspective view of a standard manual pallet jack with the manual support wheels and center supporting axle and retention pin exploded.

Figure 3 is a back-side perspective view of a chain/sprocket drive version of the Dual Driven Wheels Load Mover. It shows the chain or belt driven version of the Dual Driven Wheels Load Mover 10, the throttle assembly 100 which would be attached to the tiller handle 21 and a battery pack 30 that is removably connected to the chassis of the drive system to provide power to the system.

Figure 4 is a back-side perspective view of the same Load Mover of Figure 2, but with the exploded additional of a chain/sprocket drive version of the Dual Driven Wheels Load Mover of the present invention and without the exploded pallet jack parts from Figure 2. It shows the Dual Driven Wheels Load Mover 10 sub-assemblies and parts exploded. The wheels pivoting shaft 53 is assembled into the Load Mover 22 and a pivoting pin 54 connects both and allows the pivoting of the driving wheels. This will allow the wheels assembly 40 to tilt and keep always both driving wheels in contact with the floor independently of the conditions or the position in height of the Load Mover. A wheel sprocket 51 is attached to the driving wheel assembly 40 using standard fasteners. Note that different size sprockets can be attached to achieve different ratios and therefore different torque/speed values. A wheel chain/belt 52 is mounted into the wheel sprocket 51 and both driving wheels 40 will be assembled into the pivoting shaft 53. A center wheel cover 41 is mounted into the wheels. The chassis and motor unit 30 and front bracket 31 are assembled into the manual pallet jack hydraulic unit assembly 22 by standard fasteners. Both left side cover wheel assembly 60 and right-side cover wheel assembly 70 are mounted into the main chassis and motor unit 30. A throttle bracket 101, throttle plastic unit 102 and throttle cable 103 is assembled into the pallet jack handle assembly 21. Figure 5 is a back-side perspective view of the main chassis and motor unit of a chain/sprocket drive version exploded. It shows the main chassis and motor unit 30 parts exploded. Two controllers 110 are mounted into the chassis and back bracket 32 and into the front bracket 31. Motor sprockets 58 are mounted into motors assembly 80 that are assembled into the chassis and back bracket 32 by standard fasteners. A jack pivoting shaft 55 is assembled into the self- aligning bearing 90 that are mounted into the self-aligning bearing holder 33. Jack sprockets 56 are assembled on both sides of the jack pivoting shaft 55. Jack chain/belt 57 is mounted into the motor sprockets 58 and jack sprockets 56 to transfer the motion. The self-aligning bearing holder 33 is then mounted into the into the chassis and back bracket 32 by standard fasteners. Different size sprockets can be attached to achieve different ratios. The chassis bottom cover 34 is mounted into the chassis and back bracket 32. A battery 120 that is easily removable and rechargeable provides the necessary power to the driving unit and is mounted into the chassis and back bracket 32 with the contact being made by the battery male connector 121.

Figure 6 is a back-side perspective view of the assembled chain/sprocket drive version of Dual Driven Wheels Load Mover 10 assembled into a standard manual pallet jack 20. Throttle assembly 100 is mounted into the pallet jack handle assembly 21.

Figure 7 is a side section view of a chain/sprocket drive version of them. It shows the driving system assembly 50 of the Dual Driven Wheels Load Mover 10 section view. The motor assembly 80 transfers the motion from the motors sprocket 57 through the jack chain belt 58 to the jack sprocket 56. From the jack sprocket 56 the motion is transferred through the jack chain/belt 52 into the wheel sprocket 51 that is attached by standard fasteners into the wheel assembly 40. The shape of the wheels pivoting shaft 53 and the pivoting pin 54 allows the pivoting of the driving wheels 40. The self-aligning bearing 90 allows the pivoting of the jack pivoting shaft 55 and jack sprockets 56.

Figure 8 is a top perspective view of a chain/sprocket drive version of the driving system. It shows the complete driving system assembly 50 with all chains/belts and sprockets that transfers the motion from the motors assembly 80 to the wheels assembly 40.

Figure 9 is a top view of a chain/sprocket drive version of the driving system.

Figure 10 shows a bottom view of a chain/sprocket drive version of the Dual Driven Wheels Load Mover 10 and driving system assembly 50 when is not tilted and it shows the section lines that defines the section views of Figures 11, 12 and 13. Figure 11 is a section view of the drive unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover 10 with the section line going through the center axis of the wheels pivoting shaft. It shows the support wheel driving system when it is not tilted.

Figure 12 is a section view of the drive unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover with the section line going through the center axis of the pivoting jack shaft. It shows the jack shaft driving system when it is not tilted.

Figure 13 is a section view of the drive unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover with the section line going through the center axis of the motors, so showing that motors stage and one side of the drive transfer.

Figure 14 is a bottom view of a chain/sprocket drive version of the Dual Driven Wheels Load Mover tilted to the left side at maximum angle. It shows a bottom view of the Dual Driven Wheels Load Mover 10 and driving system assembly 50 when is tilted to the left side at maximum angle and it shows the section lines that defines the section views of Figures 15, 16 and 17.

Figure 15 is a section view of the driven unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover with wheels tilted to the left side and with the section line going through the center axis of the wheels pivoting shaft. It shows the wheel driving system when is tilted to the left.

Figure 16 is a section view of the driven unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover with wheels tilted to the left side and with the section line going through the center axis of the jack pivoting shaft. It shows the jack driving system when is tilted to the left.

Figure 17 is a section view of the driven unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover with wheels tilted to the left side and with the section line going through the center axis of the motors.

Figure 18 is a bottom view of a chain/sprocket drive version of the Dual Driven Wheels Load Mover 10 with the driving system assembly 50 tilted to the right side at a maximum angle. It shows the section lines that defines the section views of Figures 19, 20 and 21.

Figure 19 is a section view of the driven unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover with wheels tilted to the right side and with the section line going through the center axis of the wheels pivoting shaft. Figure 20 is a section view of the driven unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover with wheels tilted to the right side and with the section line going through the center axis of the jack pivoting shaft.

Figure 21 is a section view of the driven unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover with wheels tilted to the right side and with the section line going through the center axis of the motors.

Figure 22 is a section view of the driven unit of a chain/sprocket drive version of the Dual Driven Wheels Load Mover showing the pivoting system tilted to the left while driving wheels assembly 40 remains parallel to the floor.

Figure 23 is a section view of the driven unit of a direct drive version (as opposed to a chain and sprocket drive version) of a Dual Driven Wheels Load Mover, showing the pivoting system tilted to the left the same as in Figure 22, while the driving hub motor wheels assembly 45 remains parallel to the floor.

Figure 24 is a section view of the same driving and hydraulic unit of a chain/sprocket drive version of a Dual Driven Wheels Load Mover, showing the pivoting system tilted to the right while driving wheels assembly 40 remains parallel to the floor.

Figure 25 is a section view of the same driving and hydraulic unit of a chain/sprocket drive version of a Dual Driven Wheels Load Mover, showing the pivoting system vertical and upright, perpendicular to the ground but the ground being uneven and so the driving wheels assembly 40 is tilted with the uneven floor.

Figure 26 is a section view of the driving and hydraulic unit of a direct drive version (as opposed to a chain and sprocket drive version) of a Dual Driven Wheels Load Mover, showing the same conditions as in Figure 25 with the pivoting system vertical and upright,

perpendicular to the ground but the ground being uneven while the driving hub motor wheels assembly 45 is tilted with the uneven floor.

Figure 27 is the same as Figure 25 but with un-sectioned wheels, wheels sprockets and chain and wheels pivoting shaft. It shows that pivoting of the drive wheels axle / pivoting shaft 53 is greater than the pivoting of the jack pivoting shaft 59 due to the twisting/torsion allowance on the wheels chain/belt drive transfer system 52 and jack chain/belt drive transfer system 57. Therefore the total angular adjustment β is greater than β - a. (Twisting allowance is defined by the gap between links of a chain or the torsion allowance on a belt). Figures 28, 29 and 30 are side views of a complete Dual Driven Wheels Load Mover, with the driving and hydraulic unit rotated 90 degrees and the jack in a lowered position (Figure 28) and raised position (Figure 29) or fully raised position (Figure 30). This shows how the chain/belt driving wheels assembly 40 or direct/hub driven driving wheels 45 pivot on the center axle or axles 53 and so remain parallel to the floor even when the Load Mover center column and attached handle 21 are angled relative to the floor.

Figure 31 is a top view of the of a chain/sprocket drive version of a Dual Driven Wheels Load Mover, showing the allowable rotation of the handle, hydraulic and driving unit.

Figure 32 is a side perspective view of chain/sprocket drive version of the Dual Driven Wheels Load Mover 10 with a single Battery Pack 120 mounted to the Chassis and Motor Unit Assembly 30 that is installed onto a Standard Manual Pallet Jack Assembly 20. As such, there are no additional components, such as additional Battery Packs 120, mounted into or onto the Standard Pallet Jack Frame 24.

Figure 33 is the same side perspective view of Figure 32, this time with Modified Pallet Jack Frame for 2 Battery Pack Assembly Installation 26 where a front panel has been removed of the A-frame plate and in its place, the Pivoting In-Chassis 2-Battery Mount Assembly 124 has been installed, with the door shown pivoted open and the battery packs 120 being visible.

Figure 34 shows the complete chain/sprocket drive version of the Dual Driven Wheels Load Mover 10 in a Modified Pallet Jack Frame for 2 Battery Pack Assembly Installation 26, with the Pivoting In-Chassis 2-Battery Mount Assembly 124 closed.

Figure 35 shows the key components of the chain/sprocket drive version of the Dual Driven Wheels Load Mover 10 exploded, in this case with the Modified Pallet Jack Frame for 2 Battery Pack Assembly Installation 26, with the Pivoting In-Chassis 2-Battery Mount Assembly 124, but also with an additional Battery Pack 120 removably assembled to the Chassis and Motor Unit Assembly 30.

Figure 36 shows a perspective view of the chain/sprocket drive version of the Dual Driven Wheels Load Mover 10 fully assembled, but without the PowerSteering or Automation options installed.

Figures 37 and 38 show perspective views of the chain/sprocket drive version of the Dual Driven Wheels Load Mover 10 fully assembled, with the PowerSteering and the Automation options installed and those components identified per the Glossary of Components. It also shows the Modified Pallet Jack Frame for 4 Battery Pack Assembly Installation 28, with the Pivoting In-Chassis 4-Battery Mount Assembly 126. Where the Battery Pack 120 could have been removably assembled to the Chassis and Motor Unit Assembly 30, this location is instead used for the installation of a Lidar laser range finding unit and protective guard, which provides the functionality required for navigation of the entire device and localization of it in its environment.

The touch screen HMI (Human Machine Interface) 174 provides the interface to allow the operator to switch the machine from being manually operated by him to running a "mission" where the device then operates autonomously, traveling like an AGV according to its preprogrammed path.

Figures 39 and 40 show the same configuration of Dual Drive Wheels Load Mover as from

Figures 37 and 38, this time also in exploded view. In Figure 39, the steering column orientation sensor assembly 28 is identified, being atop the thrust plate and attached to it, with the pivoting handle assembly carrying the carrier 158 rotationally around the assembling, depressing the flexible circuit potentiometer to provide a position indication at all times of the orientation of the handle assembly.

Figure 41 shows a section view of this configuration of drive unit, showing also an unsectioned Lidar and sectioned protective cover in the same view.

Figure 42 shows an exploded view of the drive assembly, again with the Lidar and protective cover included.

Figure 43 shows a perspective view of an assembled Dual Driven Wheels Load Mover 10, also with the Modified Pallet Jack Frame for 4 Battery Pack Assembly Installation 28, with the Pivoting In-Chassis 4-Battery Mount Assembly 126., the automation package of Lidar and associated sensors and HMI.

Figure 44 shows the exploded view of the same configuration Dual Driven Wheels Load Mover as shown in Figure 43, with various components and assemblies labelled according to the glossary of components in this document.

Figures 45-47 show the Steering Column Orientation Sensor assembly, including the components that comprise it, with all components being labelled including 154, the flex membrane potentiometer. Figure 48 shows a partially sectioned view of the drive assembly, again with the Lidar and protective cover included.

Figure 49 shows a partially sectioned view of this configuration of drive unit.

Figures 50 - 61 graphically explain the Power Steering feature:

Figure 50 shows an assembled dual driven wheels load moving machine without the automation package but with the PowerSteer feature.

The PowerSteer feature is a very simple means of measuring the load that the operator puts on the handle grip loop 132 that he grips when he is wanting to steer the dual driven wheels load moving machine. By having some length of metal tubing between the connection point of the handle grip loop to the handle mast (the connection is approx. half way up the handle mast) the handle grip loop is able to flex slightly relative to the handle mast and this is able to be measured quite easily. The measurement point is located at the furthest point on the mast and loop from the connection point between them, so very little deflection of the metal tubing will result in a measurable relative movement at the end the handle.

By having the measurement point in this location, the sensing units, such as two simple hall sensors, can be mounted on the PCBA that is in the throttle, so very little additional componentry or connections are required. The magnet that these hall sensors would be sensing would be located very nearby and approximately centered between those sensors, but on the mast. So when the operator either pulls laterally on the handle grip loop (moving it relative to the mast) or has the handle vertical and rotates the handle grip loop (relative to the mast) the flexure in the handle assembly will result in movement of the hall sensors relative to the magnet and the increased ana log output on one hall sensor relative to the other hall sensor can be used as an input to adjust the power delivery to each motor to reduce the movement and bring the magnet back to center, which results in turning the tiller and central steering pivot to align with where the operator is pulling the handle to.

The mechanical modifications required to implement this system is minor so the overall cost of including this feature in volume production is negligible while the benefit, providing powered steering, will be very convenient for the operator as it would make the act of turning the tiller extremely effortless.

There is also negligible drive processing required - just scaling the power supply from each motor according to this input and the speed of adjustment can be very fast. There are other sensor systems that can be used, but hall sensors are very low cost and reliable when used at close range, as would be the case in this design.

(Note that the gyroscopic accelerometer located in the throttle assembly indicates when the handle is in the vertical mode and it can be assumed in software that when the handle is vertical, the operator is twisting the handle to turn the tiller vs. pulling on it laterally (such as when pulling the load with the handle pivoted down), so the scaling in that case may be different but the mechanism is the same.

Figures 52 - 54 illustrate the mechanical components involved in the power steering assembly, mostly from a side view with close-up blow-outs to show the components as labelled.

Figures 55 - 57 illustrate a front view showing the maximum deflection of the handle grip loop relative to the handle mast, with any further deflection being limited by the mechanical design feature (if it is found to be necessary) of having the diamond shaped bar 134 captive inside a slot of limited width. (In reality, this may not be necessary can will be a feature that can be eliminated). In these images, the handle grip loop is shown pul led to the left in Figure 55, so the hall sensors mounted on the throttle PCBA on the handle grip loop are pulled to the left and as the magnet mounted on the mast remains centered, that relative movement is measured. Figures 56 show the loop centered and Figure 57 show the loop pulled to the right.

Figures 58 - 59 show the same motion from Figure 55 and Figure 57 from a top view. The diamond shape is the male moving in the rectangular shape which is the female (slot).

Figures 60 - 61 show the motion when the handle mast is vertical and the operator is twisting the handle to reorient the wheels and the concept works again due to the diamond shape allowing such rotation.

GLOSSARY OF COMPONENTS

10 DUAL DRIVEN WHEELS PALLET JACK ASSEMBLY

20 STANDARD MANUAL PALLET JACK ASSEMBLY

21 PALLET JACK HANDLE ASSEMBLY

22 PALLET JACK HYDRAULIC UNIT ASSEMBLY

24 STANDARD PALLET JACK FRAME

26 MODIFIED PALLET JACK FRAME FOR 2 BATTERY PACK ASSEMBLY INSTALLATION 28 MODIFIED PALLET JACK FRAME FOR 4 BATTERY PACK ASSEMBLY INSTALLATION 30 CHASSIS AND MOTOR UNIT ASSEMBLY

31 FRONT BRACKET

32 CHASSIS FRAME

33 SELF-ALIGNING BEARING HOLDER

34 CHASSIS BOTTOM COVER

40 DRIVING WHEEL ASSEMBLY (CHAIN OR BELT DRIVEN)

41 CENTER WHEEL COVER

45 DRIVING WHEEL ASSEMBLY (DIRECT DRIVE, HUB MOTOR DRIVEN)

50 DRIVING SYSTEM ASSEMBLY

51 WHEEL SPROCKET

52 WHEEL CHAIN/BELT

53 WHEELS PIVOTING SHAFT

54 PIVOTING PIN

55 JACK SHAFT (PIVOTING)

56 JACK SHAFT SPROCKET

57 JACK SHAFT CHAIN/BELT

58 MOTOR SPROCKET

60 LEFT SIDE COVER WHEEL ASSEMBLY

70 RIGHT SIDE COVER WHEEL ASSEMBLY

80 MOTOR ASSEMBLY

85 MOTOR CONTROLLER(S)

90 SELF-ALIGNING RADIAL BEARING ASSEMBLY

100 THROTTLE ASSEMBLY

101 THROTTLE BRACKET

102 THROTTLE PLASTIC UNIT

103 THROTTLE CABLE

104 THROTTLE PCBA INCL. GYROSCOPIC ACCELEROMETER 110 CONTROLLER ASSEMBLY

120 BATTERY ASSEMBLY

121 BATTERY MALE CONNECTOR

124 PIVOTING IN-CHASSIS 2-BATTERY MOUNT ASSEMBLY

126 PIVOTING IN-CHASSIS 4-BATTERY MOUNT ASSEMBLY

130 POWER STEERING HANDLE ASSEMBLY

132 HANDLE GRIP LOOP

134 HANDLE GRIP LOOP DIAMOND BAR (MALE)

136 MOUNT BETWEEN HANDLE GRIP LOOP AND HANDLE MAST

138 HANDLE MAST

140 HANDLE MAST SLOT (FEMALE)

142 MAGNET

144 PCB MOUNTED HALL SENSOR(S)

150 STEERING COLUMN ORIENTATION SENSOR ASSEMBLY

152 LOWER POTENTIOMETER HOUSING

154 FLEX POTENTIOMETER

156 UPPER POTENTIOMETER HOUSING

158 CARRIER FOR ACTUATOR

160 HOUSING FOR ACTUATOR

162 SPRING-LOADED BALL ACTUATOR

170 AUTOMATION PACKAGE

172 LIDAR

173 PROTECTIVE COVER FOR LIDAR

174 HMI TOUCHSCREEN

176 FRONT AND REAR FACING CAMERAS

178 ON-BOARD COMPUTER

Claims

CLAIMS "DUAL DRIVEN WHEELS LOAD MOVER"

1. A dual driven wheels powered pallet jack or similar design of load moving device comprising:

- A frame, adapted for attachment to the steering column, hydraulic pump and attached handle assembly of a pallet jack or similar device;

- Two driven support wheels mounted onto a drive axle or two co-axial drive axles, the driven wheels being located either side of the vertical axis of the steering column;

- Two independently driven motors that provide the rotational power to drive each driven support wheel that in turn generates the device's motive power.

2. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 1 in which the power train that transfers the power from the two independent motors to the two driven support wheels consists of one or more sets of chains and sprockets, belts and pulleys or a combination thereof.

3. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 1 in which the two driven support wheels are rotated by independent motors that are located inside of each support wheel, so being of 'hub motor' or 'direct drive' design.

4. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 1 in which the power train for the two driven support wheels consists of two independent motors that are located outside of but adjacent to the driven wheels and the power transfer method is by means of gear engagement or by friction contact.

5. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 1 in which the axle(s) are able to pivot relative to the pallet jack that they are attached to, allowing the driven wheels to maintain contact with the ground while traveling over uneven ground, or to accomodate changes in the angle of the dual driven wheels assembly relative to the ground.

6. The dual driven wheels powered pallet jack or similar design of load moving device comprising:

- A frame, adapted for attachment to a pallet jack or similar device;

- Two driven support wheels rotatably mounted to the hydraulic lifting cylinder of the steering column of the jack;

- Two independently driven motors that provide the rotation to the driven support wheels;

- A throttle that an operator can variably adjust to provide the instruction to the device as to a speed it should travel at;

- Two single channel output motor controllers (one for each motor), or one dual channel output motor controller that powers the two motors according to the input provided by the operator via the throttle; - One or more battery packs able to be attached to the device or the frame of the pallet jack itself to provide power to the drive system.

- A power steering mechanism by which the force that the operator applies to the handle tiller is able to be measured and thus the speed of the motors modified to steer the device in such a way as to reduce the effort that the operator exerts to turn the device, improving the maneuverability of the dual driven wheels powered pallet jack or similar design of device.

7. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 6 wherein one or more battery packs can be mounted to the frame of the device.

8. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 6 wherein one or more battery packs can be mounted to the frame of the pallet jack, with the physical room being present to mount multiple or larger battery packs and therefore provide more running time before the battery packs need to be removed and recharged.

9. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 6 wherein there is a predictable amount of flexure built into the handle assembly, between the handle grip that the operator holds when directing the device and the handle mast.

10. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 6 wherein the flexure can be measured, such as by one or more hall sensors on either the handle grip or handle mast, and one or more magnets mounted to the other, such that the relative movement between the two as steering is taking place will provide a variable value that can be used to increase and/or decrease the speed of one or both of the motors to reduce the amount of flexure and thereby effectively reduce the amount of exertion that the operator applies to the handle grip to elicit a turning effect on the device.

11. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 6 wherein the measure from this flexure can be calibrated according to both the amount of flexure in that particular handle assembly, or according to how sensitive the operator likes the power steering to be.

12. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 6 wherein the mechanism allows limited flexure so that the handle assembly does not feel too loose in the operator's hand, while allowing both lateral movement of the handle grip relative to the handle mast, being a measure applicable if pulling a load under power, plus rotational movement of the handle grip relative to the handle mast, being a measure applicable if turning the handle assembly and attached driven wheels when the unit is stationary or travelling at a slow speed and the handle assembly is in a relatively vertical orientation.

13. A dual driven wheels powered pallet jack or similar design of load moving device comprising: - A frame, adapted for attachment to a pallet jack or similar device;

- Two independendtly driven support wheels rotatably mounted to the hydraulic lifting cylinder of the jack;

- Two single channel output motor controllers (one for each motor), or one dual channel output motor controller that powers the two motors according to the input provided by the operator via the throttle;

- Additional componentry, the choice of which varies according to other criteria such as cost, required functionality and the state of the technology available, that can control the differential drive created by the two independently driven support wheels located about the steering column of the device.

14. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 13 further any combination of the following sensors:

- A rotational position sensor such as a flexible potentiometer mounted on the rotating steering column of the device that measures its rotation relative to the pallet jack and therefore its orientation, this value being used to determine the course to take when navigating without the steering coming from an operator.

- One or more sensors such as radio signal sensors that can read the strength of a radio signal being transmitted by a wire embedded in the floor. This is a form of AGV (Automated Guided Vehicle) travel;

- One or more sensors such as guide sensors, typically magnetic sensors or RGB cameras that follow a line (paint or colored tape or magnetic tape) for line following travel, so as to provide AGV-like navigation on pre-defined paths.

- One or more sensors such as Lidar (Light Imaging, Detection And Ranging) lasers to provide mapping data, localization data and aid in the navigation of the device for the purpose of autonomous travel;

- One or more sensors that can provide laser target navigation where reflectors or reflective tape is mounted about the environment being navigated and the laser transmitter and receiver, typically mounted into a rotating turret, senses these targets and determines location and course accordingly.

15. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 13 where an on-board computer may be included to process the information being received from the sensors and to assist in the navigation process, providing the high level instructions to the motor controllers.

16. The dual driven wheels powered pallet jack or similar design of load moving device of Claim 13 where a wireless communication device in included in the machine, such as for communication by WiFi or Bluetooth technology so that an off-board computer may communicate navigation instructions to the powered pallet jack.