EP4652062A1

EP4652062A1 - Removable system pack for electric work machine

Info

Publication number: EP4652062A1
Application number: EP23844505.0A
Authority: EP
Inventors: Paul KEMBLE; Alan G. DAVIES
Original assignee: Caterpillar Inc
Current assignee: Caterpillar Inc
Priority date: 2023-01-19
Filing date: 2023-12-19
Publication date: 2025-11-26
Also published as: GB2626529A; GB202300773D0; GB2626529B; WO2024155404A1; CN120500420A

Abstract

A system pack (11) for mounting in a work machine (10) comprising a pack frame (50) and a pack power system (60) mounted to the pack frame. The pack frame comprises a power source mount (51) receiving a power source (45). The pack frame is for mounting and removing the system pack from the work machine. The pack power system is mounted to the pack frame and is connected to the power source. A pack power distribution interface (61), when the system pack is mounted in the work machine, electrically connects at least one motor (41) of the work machine to supplying power thereto. The pack charging interface is mounted to the pack frame and connected to the pack power distribution interface. The pack charging interface connects to an external power source for charging the power source when the power source is mounted to the frame.

Description

REMOVABLE SYSTEM PACK FOR ELECTRIC WORK MACHINE

Technical Field

This disclosure is directed towards a system pack for mounting in a work machine and a work machine assembly comprising at least one system pack and the work machine. The disclosure further relates to a method of maintaining such a work machine assembly.

Background

Electric work machines, such as wheel loaders, excavators, trucks and the like, may comprise a storage battery inside the work machine that is charged with power using an external vehicle charging apparatus. Such batteries, particularly those for electrified excavators, are very bulky. The batteries also needing to be accessible for battery swapping, whether as part of routine maintenance or to quickly remove a depleted battery and replace it with a fully charged battery. Furthermore, installation and maintenance of critical system components of the machine can be difficult to achieve around the batteries and/or around a compartment in which the battery is mounted. Such system components may include the battery power system, controllers, power electronics, coolant systems and thermal management systems.

US20220289067A1 discloses a universal battery pack, electric vehicle powertrain design and battery swapping network with battery health management. The electric vehicle powertrain design is equipped with swapping capability, the modular swappable battery packs, battery storage apparatus, and the bidirectional charging systems. Such an arrangement, however, does not adequately address the aforementioned issues.

Summary

An object of the present disclosure is to provide a work machine assembly with an improved installation, maintenance and removal solution for batteries (which in the present disclosure includes fuel cells) and associated systems. A further object is to provide improved methods of installation, maintenance and removal of batteries and associated systems.

The present disclosure therefore provides a system pack, work machine assembly and method in accordance with the claims.

The system pack comprises a pack frame and a power system and charging interface mounted to the pack frame. A power source is mountable on the power source mount of the pack frame and connectable to the power system and charging interface. The pack frame enables the pack to be removable mounted in the work machine. A power distribution interface enables the power system to transfer power from the power source to at least one motor, which may be electric, of the work machine. The at least one motor is for performing work, such as driving the work machine across a terrain and/or controlling work tools of the work machine.

The system pack effectively may form a complete power cassette with its own charging, cooling and/or control capability, with all supporting hardware as applicable. Easy access to the power source and related systems is achieved by virtue of the entire system pack being removable from and replaceable in the work machine. In addition, the system pack may provide a drop in power solution for a wide range of power demands.

The system pack is a separate modular item from the work machine and the work machine assembly may comprise a plurality of systems packs for a single work machine, thereby reducing downtime of the work machine since system packs can be immediately replaced by others prior to maintenance thereon. The system pack may comprise substantially all components of the electrical vehicle power drive or traction systems or static machine power system, other than the motors and electronics, cable and/or harness between the motors and the power distribution interface.

The charging interface is for connection to an external power source for charging the power source when the power source is mounted to the pack frame. The charging interface may enable the charging of the power source when the system pack is mounted in or is external to (i.e., not mounted in) the work machine, thereby significantly improving recharging flexibility.

The pack frame may comprise a lifting mount for a loader to mount to in order to lift the system pack and power source therein into the work machine. The loader may be any type of suitable lifting mechanism. Such a lifting mount may particularly be a crane and/or forklift lifting mount and, as a result, the system pack may be easily transportable and installable in the work machine by crane and forklift.

The system pack may also comprise supporting systems, such as a pack coolant system and/or thermal management system. The pack coolant system may be for cooling at least one component of the work machine (such as the at least one motor, hydraulics or actuator). The power source thermal management system may be for cooling the power source when mounted to the system pack. The pack coolant system may connect to a machine coolant system, the machine coolant system directing transfer fluid to cool the at least one motor, and the pack coolant system may control the flow of transfer fluid to the machine coolant system, thus controlling cooling of the at least one motor. The power source thermal management system may be dedicated to heating and/or cooling the power source and/or the pack power system and may comprise at least one fan or the like. As a result, ease of access to and maintenance of the motor, power source and power system cooling systems may be improved by virtue of being removable with the system pack from the work machine for maintenance.

The power system may comprise at least one motor control, which may comprise an inverter, connected to the power distribution interface for supplying high voltage power to the at least one motor and/or low voltage power to machine electrical systems, other than to the at least one motor. As a result, ease of access to the motor controls may be improved by virtue of being removable with the system pack from the work machine for maintenance. Brief Description of the Drawings

By way of example only, embodiments of the present disclosure are now described with reference to, and as shown in, the accompanying drawings, in which:

Figure l is a schematic side view of an embodiment of a work machine assembly in accordance with the present disclosure;

Figure 2 is a front perspective view of an embodiment of a system pack according to the present disclosure for the work machine assembly of Figure 1;

Figure 3 is a rear perspective view of the system pack of Figure 2; and

Figure 4 is a schematic layout of an embodiment of the electrical and hydraulic systems of the work machine assembly of Figure 1.

Detailed Description

Figure 1 illustrates an embodiment of a work machine assembly 9 according to the present disclosure comprising a work machine 10 and a system pack 11 removably mounted in the work machine 10. The illustrated work machine 10 is a wheel loader and is for excavating material from a terrain 15 (for example the ground and/or worksite), but the work machine 10 of the present disclosure may any other type of work machine 10. The work machine 10 may, for example, be any of a fork truck mast, auger, vibrating pile rig, broom, excavator, backhoe, mulcher, planer, fixed teleboom, rotating loader, rotating teleboom, pipe handler, log handler, crane, snow pusher or plough, salt spreader, grader, shredder, feed mixer, water pump, generator, dumper, vacuum excavator, snow blower, tree trimmer, personal access platform, concrete mixer, roller, compactor, stacker, recovery vehicle, auto salvage cut out tool, auto salvage forks, military applications, water cannon, crusher, fire and rescue applications, sweeper, concrete pump, agricultural machinery, agricultural vehicle and/or concrete mixer. The work machine 10 is configured for performing work and may be a vehicle or static machine. The work machine 10 may comprise a machine body 12 having a cab 8 for an operator and an arm arrangement 14 attached to the machine body 12. Alternatively, the work machine 10 may be an autonomous vehicle and thus may not comprise a cab 8 for an operator. The work machine 10 may comprise a tool 15 connected to the arm arrangement 14. The work machine 10 may comprise at least one tool actuator 18, which may be hydraulic or electric, for controlling the orientation and movement of the arm arrangement 14 and thereby the orientation and movement of the tool 15. The tool 15 may be of any suitable type and may, for example, be a shovel as illustrated or may be a bucket, tiltable bucket, grapple, tilt rotator, hammer, handling arm, multi-processor, pulveriser, saw, shears, blower, grinder, tiller, trencher, winch, auger, broom, cutter, planer, delimber, felling head, mulcher or rake.

The work machine 10 may be configured predominantly for off- highway operation and/or may comprise off-highway wheels 13 or tracks mounted to an off-highway suspension system. However, the work machine 10 may be approved for on highway use in certain configurations, such as when forming an agricultural vehicle, telehandler or loader.

The work machine 10 may comprise a machine compartment 27 for receiving the system pack 11 therein. The work machine 10 may comprise a hood, bonnet and/or door 28 for closing the machine compartment 27 with the system pack 11 therein.

Systems of the work machine 10 are also illustrated schematically in Figure 4. Parts mounted within the system pack 11 are illustrated within the boundary line I la.

The work machine 10 may comprise a hydraulic system 5 for operating at least one work tool, such as tool 15 and around which fluid may be circulated. The work machine 10 may comprise a machine control system 29 for controlling the hydraulic system 5 automatically or based upon inputs received from an input device 6 controllable by an operator in the machine body 12, such as a joystick or at least one button. The hydraulic system 5 may comprise a hydraulic reservoir 25, a hydraulic pump 26 and hydraulic hoses (not shown). The hydraulic system 5 may comprise at least one hydraulic actuator 18 and/or other hydraulic components 21 for controlling the pivoting of the arm arrangement 14 and the tool 15. The hydraulic system 5 may also comprise a hydraulic fluid cooler 24 for cooling hydraulic fluid within the hydraulic system 5.

The work machine 10 comprises a machine power system 40 comprising at least one motor 41 for performing work, such as driving the work machine 10 across the terrain 33 and/or operating tool 15. The at least one motor 41 may be mounted in the machine body 12 and connected directly or indirectly to the at least one wheel and/or track 13. The machine power system 40 may comprise a low voltage power source 43, which may for example comprise a battery and/or fuel cell, connected to a low voltage machine electrical system 44. The term “low voltage” refers to a lower voltage than “high voltage”, referred to below, and may be 12V and/or 24V. The low voltage machine electrical system 44 provides power to components of the work machine 10 other than the at least one motor 41, such as to lights, the machine control system 29 and the like.

The machine power system 40 may further comprise a machine power distribution interface 42, which is accessible in and mounted in the machine compartment 27, for connection to the system pack 11. The machine power distribution interface 42 may be connected to the at least one motor 41, low voltage power source 43 and/or low voltage machine electrical system 44. The machine power distribution interface 42 may comprise a plurality of separate interfaces, for example for high and low voltage power transfer. In Figure 4, the machine power distribution interface 42 is not illustrated, but is formed at the boundary I la.

As best illustrated in Figures 2 and 3, the system pack 11 comprises a pack frame 50 to which the other components of the system pack 11 are mounted. The pack frame 50 is for mounting and removal of the system pack 11 from the work machine 10. The pack frame 50 is configured such that all parts of the system pack 11 can be mounted to it prior to insertion into the work machine 10 and so that, upon insertion into the work machine 10, all parts of the system pack 11 are inserted with the pack frame 50.

The pack frame 50 comprises a plurality of mounting points for receipt of the components of the system pack 11 and the arrangement of the pack frame 50 may be determined according to the type and layout of work machine 10 for which it is designed. The pack frame 50 may comprise a plurality of frame elements, such as bars, rods, sheets, platforms and the like, fastened together, such as by bolts, welding or the like. In particular, the pack frame 50 may comprise a main frame body 55, which may be substantially vertical, and a plurality of supports and/or shelves 56 extending, optionally substantially horizontally, from the main frame body 55. The pack frame 50 may comprise a pair of frame sides 57 extending from the opposite side of the main frame body 55 to the plurality of shelves 56, and along the opposing vertical outer edges of the main frame body 55, defining a space therebetween.

The pack frame 50 comprises a power source mount 51 for receiving a power source 45, which may comprise at least one battery, a plurality of batteries, at least one fuel cell or at least one other such electrical energy store or source, may be a high voltage power source and may be for supplying power to the at least one motor 41. The power source mount 51 may be formed in the space between the frame sides 57. In the illustrated embodiment, a plurality of power sources 45 form a power source pack 46, which is mountable to the power source mount 51. The power source mount 51 may comprise at least one mount foot 52, which is connectable to the power source pack 46 and mountable on at least one mount shelf 53 of the pack frame 50.

The pack frame 50 may comprise a lifting mount 58 for a loader to mount to in order to lift the system pack 11 and power source 45 therein into and/or onto the work machine 10. As illustrated, the lifting mount 58 may form part of the pack frame 50, particularly the at least one mount foot 52. The lifting mount 58 may comprise mounts for receiving forks of a forklift truck as shown in Figures 2 and 3. The system pack 11 comprises a pack power system 60 mounted to the pack frame 50 and is for connection to the power source 45. The pack power system 60 may also be considered to comprises the power source 45. The pack power system 60 comprises all electrical power components mounted to the pack frame 50, with each component mounted to the shelves 56 and/or frame sides 57 as appropriate for the layout of the work machine 10 it is designed for. The pack power system 60 is illustrated in Figures 2 to 4.

The pack power system 60 comprises a pack power distribution interface 61, mounted to the pack frame 50, for, when the system pack 11 is mounted in the work machine 10, electrical connection to the at least one motor 41 of the work machine 10 for supplying power thereto, such as from the power source 45. The pack power distribution interface 61 may be connectable to the machine power distribution interface 42 when the system pack 11 is mounted in the machine compartment 27, as illustrated in Figure 1. The pack power distribution interface 61 may comprise a plurality of separate interfaces, for example for high and low voltage power transfer. In Figure 4, the pack power distribution interface 61 is not illustrated, but is formed at the boundary I la.

The pack power system 60 may comprise at least one motor control 62, mounted to the pack frame 50, for connection to the power source 45 and connected to the pack power distribution interface 61. The at least one motor control 62 may be at least one inverter and may be for providing a high voltage power output to the pack power distribution interface 61 for providing power to the at least one motor 41. The pack power system 60 may comprise a motor control for each motor 41 of the work machine 10.

The pack power system 60 may comprise at least one converter 63, mounted to the pack frame 50, for connection to the power source 45 and connected to the pack power distribution interface 61. The converter 63 is for providing a low voltage power output to the pack power distribution interface 61 for providing power to the machine electrical system 44 (other than the at least one motor 41). The pack power system 60 comprises at least one pack charging interface 65, 66 mounted to the pack frame 50 for connection to the power source 45 and connected to the pack power distribution interface 61. The at least one pack charging interface 65, 66 is for connection to an external power source for charging the power source 45 when the power source 45 is mounted to the frame 50. The at least one pack charging interface 65, 66 enables the power source 45 to be charged whilst it is mounted in the system pack 11.

The at least one pack charging interface 65, 66 may comprise an on-board charging interface 65 and/or an off board charging interface 66. The onboard charging interface 65 may be configured to receive AC power, such as from an AC power network, and convert it to DC power for charging the power source 45. The on-board charging interface 65 may comprise at least one rectifier for AC -DC conversion. The off board charging interface 66 may be configured to receive DC power, such as from a dedicated charging station providing a DC power output, for charging the power source 45 without conversion from AC. The at least one pack charging interface 65, 66 may comprise a single charging interface 65, 66 (i.e., a single port) configured to receive AC or DC power. The single charging interface 65, 66 may comprise at least one rectifier for AC -DC conversion between AC power received at the single charging interface 65, 66 and the power source 45.

The at least one pack charging interface 65, 66 may be connected to alternating or direct current chargers. In some embodiments, the pack power system 60 may comprise a screen, display or the like for displaying status of the components of the pack power system 60, including power source charge and/or the like. The pack power system 60 may also include controls, a controller and/or the like for adjusting performance, status or the like of the pack power system 60 and/or the components of the pack power system 60.

The system pack 11 may comprise a pack coolant system 70 and the work machine 10 may comprise a machine coolant system 71, the machine coolant system 71 being for cooling at least one component of the work machine 10. The at least one component may be the at least one motor 41, at least one actuator and/or at least one condenser. The machine coolant system 71 may comprise a transfer fluid flowing through the machine coolant system 71, which may comprise at least one conduit, heat exchanger or the like. The flow of transfer fluid may control a transfer of heat with the at least one motor 41.

The pack coolant system 70 may comprise a pack coolant system connector 72 (not illustrated, but at the boundary 1 la in Figure 4) for connecting the pack coolant system 70 to the machine coolant system 71. The machine coolant system 71 may comprise a machine coolant system connection 77 for connection to the pack coolant system connector 72. The pack coolant system 70 may be connected to and powered by the power source 45.

The pack coolant system 70 may be operable to cool and/or control the transfer of heat with the at least one motor 41 via the machine coolant system 71 when they are connected by the pack and machine coolant system connectors 72, 73. In particular, the pack coolant system 70 may comprise a transfer fluid, for example travelling through conduits, and the pack coolant system connector 72 may be for, when connected to the machine coolant system 71, transferring the transfer fluid between the pack coolant system 70 and machine coolant system 71.

The pack coolant system 70 may comprise at least one fluid pump 73 for pumping transfer fluid through at least one fluid cooler 74 and around the pack and machine coolant systems 70, 71.

The system pack 11 may further comprises a power source thermal management system 75 configured for controlling the temperature and/or heating and/or cooling the power source 45 when mounted to the power source mount 51. The power source thermal management system 75 may comprise at least one power source fan 76 connected to the pack power system 60 for cooling the power source 45 and/or low voltage power source 43. The power source thermal management system 75 may also be formed at least partially by and/or comprised by the pack coolant system 70, particularly via the transfer fluid. Hence the pack coolant system 70 may control the temperature of both the power source 45 and at least one motor 51. The power source thermal management system 75 may be connected to and powered by the power source 45.

The system pack 11 may further comprise a pack control system 80 for controlling the components of the system pack 11. The pack control system 80 may comprise at least one pack controller 81 connected to and for controlling the power source 45, pack power system 60, pack power distribution interface 61, at least one motor control 62, at least one motor control and/or converter 63, pack coolant system 70, pack coolant system connector 72, at least one fluid pump 73, at least one fluid cooler 74, power source thermal management system 75, at least one power source fan 76 and/or pack charging interface 65. The pack control system 80 may be connected to and powered by the power source 45.

The pack control system 80 may comprise a pack control connector 82 for connecting the pack control system 80 to the machine control system 29. The machine control system 29 may comprise a machine control connector 83 for connection to the pack control connector 82. The pack control system 80 may be configured to control the components of the system pack 11 rather than the machine control system 29. The pack control system 80 may have instructions stored on the pack controller 81 for running the components of the system pack 11, such as the pack coolant system 70.

Industrial Applicability

During manufacture and/or maintenance, all components of the system pack 11 may be mounted to the pack frame 50 prior to or without installation of the power source 45. Therefore, components can be mounted and connected to one another with full visibility around the system pack 11, significantly improving the ease and efficiency of manufacture and/or maintenance.

The power source 45 may subsequently be mounted to the power source mount 51 and connected to the pack power system 60. The system pack 11 may be lifted, such as via the lifting mount 58, into the machine compartment 27. Either prior to or after mounting in the machine compartment 27, the various systems may be connected together. The pack control system 80 may be connected to the machine control system 29 by connected the pack and machine control connectors 82, 83 together.

The pack power distribution interface 61 may be connected to the machine power distribution interface 42 to connect the pack power system 60 to the machine power system 40. The pack coolant system 70 may connected to the machine coolant system 71 by the pack and machine coolant system connectors 72, 73. Hence, relatively simple final connections are required for the final installation of the system pack 11 in the work machine 10, as compared to having to individually install separate components of the system pack 11 in the work machine 10.

Manufacture, installation and maintenance of the work machine assembly 9 is improved as the system pack 11 can be assembled outside of the work machine 10, including attachment of components to the pack frame 50 and routing of all cables, prior to location in the work machine 10. Connection of the power distribution interface 61 to the work machine 10 may comprise only the connection of less than ten separate connections. In addition, the power source 45 may be mountable on the power source mount 51 when the system pack 11 is mounted or not mounted in the work machine 10. Hence, if the power source 45 is particularly heavy, ease of installation is improved since it can be installed on its own after the rest of the system pack 11 has been mounted in the work machine 10.

The work machine assembly 9 may comprise a plurality of system packs 11 for each work machine 10. As a result, if a first system pack 11 in a work machine 10 requires maintenance, it can be swapped for a second system pack 11 immediately prior to maintenance of the first system pack 11. Therefore, downtime of the work machine 10 may be significantly reduced.

Claims

1. A system pack for mounting in a work machine, the work machine comprising at least one motor for performing work, wherein the system pack comprises: a pack frame comprising a power source mount for receiving a power source, the pack frame being configured for mounting and removal of the system pack from the work machine; and a pack power system mounted to the pack frame and for connection to the power source, the pack power system comprising: a pack power distribution interface for, when the system pack is mounted in the work machine, electrical connection to the at least one motor of the work machine for supplying power thereto; and a pack charging interface mounted to the pack frame and connected to the pack power distribution interface, the pack charging interface being for connection to an external power source for charging the power source when the power source is mounted to the frame.

2. A system pack as claimed in claim 1 wherein the system pack comprises the power source mounted to the power source mount.

3. A system pack as claimed in claim 1 or claim 2 wherein the system pack further comprises a pack control system, the pack control system comprising at least one pack controller for controlling the power source, pack power system and/or charging interface.

4. A system pack as claimed in claim 3 wherein the pack control system comprises a control connector for connecting the pack control system to a machine control system of the work machine.

5. A system pack as claimed in any one of the preceding claims wherein the system pack comprises a pack coolant system, the pack coolant system comprising a pack coolant system connector for connecting the pack coolant system to a machine coolant system of the work machine such that the pack coolant system is operable to cool at least one component of the work machine via the machine coolant system.

6. A system pack as claimed in claim 5 wherein the pack coolant system comprises a transfer fluid and the coolant system connector is for, when connected to the machine coolant system, transferring the transfer fluid between the pack coolant system and the machine coolant system.

7. A system pack as claimed in claim 6 wherein the pack coolant system is connected to and controlled by the pack control system.

8. A system pack as claimed in any one of the preceding claims further comprising a power source thermal management system configured for heating and/or cooling the power source when mounted to the power source mount.

9. A system pack as claimed in any one of the preceding claims wherein the pack power system comprises at least one motor control for connection to the power source and connected to the pack power distribution interface.

10. A system pack as claimed in claim 9 wherein the at least one motor control is for providing a high voltage power output to the pack power distribution interface for providing power to the at least one motor.

11. A system pack as claimed in any one of the preceding claims wherein the pack power system comprises at least one converter for connection to the power source and connected to the pack power distribution interface.

12. A system pack as claimed in claim 11 wherein the converter is for providing a low voltage power output to the pack power distribution interface for providing power to a machine electrical system, other than the at least one motor, of the work machine.

13. A system pack as claimed in any one of the preceding claims wherein the pack frame comprises a lifting mount for a loader to mount to in order to lift the system pack and power source therein into the work machine.

14. A work machine assembly comprising: a work machine comprising: a machine body; at least one motor mounted to the machine body and for performing work; and a system pack compartment having a machine power distribution interface accessible therein; and at least one system pack removably mountable in the system pack compartment, the or each system pack comprising: a pack frame comprising a power source mount for receiving a power source; and a pack power system mounted to the pack frame and for connection to the power source, the pack power system comprising: a power distribution interface releasably connectable to the machine power distribution interface such that the pack power system is able to supply power from the power source to the at least one motor; and a pack charging interface mounted to the pack frame and connected to the pack power system, the pack charging interface being for connection to an external power source for charging the power source when the power source is mounted to the frame.

15. A method of maintaining the work machine assembly of claim 14 comprising: removing the system pack from the work machine, performing a maintenance task on the system pack and replacing the system pack in the work machine; or removing the system pack from the work machine and mounting a different system pack in the work machine.