Description:TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to hybrid systems for heavy machinery. Specifically, it relates to a hybrid conversion system for diesel excavators that integrates an electric vehicle (EV) motor alongside an existing diesel engine. This enables a seamless operation of the system in both electric vehicle and diesel modes without reliance on batteries or energy storage devices.

BACKGROUND OF THE INVENTION
[0002] Diesel excavators are widely used in construction, mining, and infrastructure projects due to their reliability and power. However, they are associated with significant drawbacks, such as high fuel consumption, frequent maintenance, complex servicing, and environmental concerns due to emissions and noise pollution. Existing hybrid solutions often rely on bulky and expensive batteries, which add complexity, weight, and cost to the system while increasing maintenance requirements.

[0003] Patent Literature US20120082536 relates to a motor generator control unit that controls operation of a motor generator which generates power using a driving force transmitted from an engine. A charge/discharge control unit electrically connects a first capacitor and a second capacitor and controls charging/discharging of power between the first capacitor and the second capacitor in response to an externally supplied control signal. A motor which is electrically connected to the second capacitor is capable of regenerating electric energy and storing the regenerated energy in the second capacitor. A control device supplies a control signal to at least one of the motor generator control unit and the charge/discharge control unit and reduces a target charging value of at least one of the first capacitor and the second capacitor before the motor regenerates energy. Therefore in US20120082536, a couple of capacitors are utilized which aid in regeneration and for storage of electricity.

[0004] Patent Literature JP5957475B2 relates to a hybrid type hydraulic shovel comprising a floor member including a driver seat, on which an operator sits, provided on the left side as one side in the right and left direction of a revolving frame; a fuel tank for storing fuel inside on the right side as the other side of the right and left direction of the revolving frame; a power storage device accommodation space extending in the front and rear direction and in the upper and lower direction between the floor member and the fuel tank; and a power storage device disposed in the power storage device accommodation space. Thereby, the hybridized hydraulic shovel can be obtained by using an existing hydraulic shovel without changing arrangement of apparatuses such as an engine and the fuel tank disposed on a revolving super structure. Here, it is notable that the electric motor and the diesel engine are linked to work together.

[0005] Existing diesel machinery/excavators face several challenges, including high fuel consumption, which increases operational costs, and significant maintenance requirements due to numerous moving parts. Their complex serviceability often leads to longer downtime and higher repair costs. Additionally, they contribute to environmental pollution through higher emissions, generate excessive noise and vibrations that affect workplace conditions, and offer limited ROI due to inefficiencies. Moreover, these machines face increasing regulatory challenges as stricter environmental and noise standards are enforced.

[0006] The need for a cost-effective, eco-friendly, and versatile alternative to conventional diesel machinery excavators has driven the development of hybrid systems. However, current solutions fail to provide independent operation of electric vehicle (EV) motors and diesel engines without dependency on energy storage devices. The present invention addresses these challenges by ensuring that the electric motor and the diesel engine of the system operate entirely independently, without any direct linkage between them. Additionally, the invention excludes the use of power storage or regenerative devices, as it is directly connected to a power supply through a cable.

OBJECT OF THE INVENTION
[0007] A primary objective of the present invention is to provide a hybrid conversion system for a heavy machinery that enables an independent operation of either the electric vehicle motor or the diesel engine according to an embodiment of the present invention.
[0008] Another objective of the present invention is to eliminate the need for batteries, capacitors, or inverters, thereby reducing costs and maintenance requirements, according to an embodiment of the present invention.

[0009] Another objective of the present invention is to provides a seamless switching mechanism for operators to toggle between Electric and diesel modes, according to an embodiment of the present invention.

[0010] Yet another objective of the present invention is to offers zero-emission operation in EV mode, addressing environmental concerns and regulatory compliance.

[0011] Other objectives of the present invention, as well as particular features, elements and advantages thereof, will be clarified in or be apparent from the following description and the accompanying figures.

SUMMARY OF THE INVENTION
[0012] The following summary is provided to facilitate a clear understanding of the new features in the disclosed embodiment and it is not intended to be a full, detailed description. A detailed description of all the aspects of the disclosed invention can be understood by reviewing the full specification, the drawing and the claims and the abstract, as a whole.

[0013] The present invention relates to hybrid conversion system for an excavator that integrates an existing diesel engine with an electric vehicle (EV) motor, offering dual-mode operation. An aspect of the system is configured to extend the chassis by 600–800 mm which is also reinforced to accommodate the EV motor and its components. Separate hydraulic pumps are installed for the diesel engine and EV motor, managed by non-return control valves to prevent backflow of hydraulic oil and ensure exclusive operation of the active pumps. A cabin switch facilitates seamless switching between diesel and electric modes without requiring additional equipment or battery packs.

[0014] Another aspect of the present invention is that the EV motor operates with zero emissions and is directly connected to an external power supply via a cable. Independent cooling mechanisms are implemented for the diesel engine and EV motor, with a hydraulic oil cooler positioned near the EV motor to optimize performance. Electrical protection is ensured through a Current Protection Transformer (CPT) board and a high-performance control panel that regulates electricity inputs and prevents power fluctuations and short circuits.

[0015] Yet another aspect of the present invention relates to operational flexibility which is achieved by enabling the diesel engine and EV motor to function independently, depending on the requirements. The system provides seamless mode transitions and maintains independent hydraulic pump operations for each power source. This hybrid setup further utilizes a hydraulic electrical motor mounting flange for the EV motor. The method of operation includes chassis extension, component installation, integration of hydraulic pumps and cooling systems, and smooth switching via the cabin switch, enabling efficient and eco-friendly excavation operations.

BRIEF DESCRIPTION OF DRAWINGS
[0016] The detailed description is described with reference to the accompanying figure(s). Throughout the drawing(s), the same drawing reference numerals will be understood to refer to the same elements and features. The features and advantages of the present proposed system will become more apparent from the following detailed description a long with the accompanying figures, which forms a part of this application.

[0017] Fig.1 depicts a schematic view of a hybrid machinery comprising both the diesel engine and the electric vehicle motor as an embodiment of the present invention
[0018] It is to be noted, however, that the appended drawing illustrates only a typical embodiment(s) of this system and is therefore should not be considered limiting of its scope, for the system may admit to other equally effective embodiments.

REFERENCE NUMERALS
10 – Diesel engine
20 – electric vehicle motor
30 – cabin switch
40 – hydraulic pump (diesel engine)
50 – hydraulic pump (electric vehicle motor)
60 – non-return control valves
70 – diesel tank
80 – hydraulic electrical motor mounting flange
90 – radiator
100 – hydraulic oil cooler
110 - control panel
120 -control valve
DETAILED DESCRIPTION OF THE INVENTION
[0019] The following is a detailed description of the present disclosure depicted in the accompanying drawing(s). However, it may be understood by a person having ordinary skill in the art that the present subject matter may be practiced without these specific details. The subject matter of the disclosure will be more clearly understood from the following description of the embodiments thereof, given by way of example only with reference to the accompanying drawings, which are not drawn to scale.

[0020] If the specification states that a component or a feature “may” or “can” be included, that particular component or feature is not required to be included or have the characteristic. The use of open-ended terms like “comprising” and variations herein is meant to encompass the steps listed thereafter and equivalents thereof as well as additional items. As used herein, the singular forms “a,” “an,” and “the” designate both the singular and the plural, unless expressly stated to designate the singular only.

[0021] The terms “comprise”, “comprising”, “includes”, “including”, “containing”, “characterized by”, “having” or any other variation thereof, are intended to cover a non-exclusive inclusion.

[0022] The terms “preferred” and “preferably” refer to embodiments of the invention that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

[0023] The term “EV” refers to an “electric vehicle” that can be powered by an electric motor that draws electricity from a battery and is capable of being charged from an external source. “Control power transformers” (CPTs) are devices that are imperative in stepping up/down and regulating voltages for industrial control and automation applications. The term “active pump” refers to the operational pump currently supplying hydraulic oil to the system, depending on the selected mode of operation - Diesel Engine or Electric Motor.

[0024] The present invention relates to a hybrid conversion system for a heavy machinery and is designed to enable efficient operation in both electric vehicle (EV) and diesel modes. According to a preferred embodiment of the present invention, the hybrid conversion system relates to a diesel excavator. The disclosed hybrid conversion system retrofits diesel excavators with an EV motor mounted on an extended and reinforced chassis, alongside the existing diesel engine. The system operates in two distinct modes:
[0025] The EV mode, wherein the EV motor powers the excavator using an external power source, with the diesel engine completely shut down.The Diesel mode wherein the excavator operates as a traditional diesel system, with the EV motor inactive

[0026] Fig.1 presents a hybrid system of a machine that integrates an electric vehicle (EV) motor (20) alongside an existing diesel engine (10) on an extended chassis, according to a preferred embodiment of the present invention. The present invention therefore, enables independent operation of both systems. Moreover, this configuration allows seamless switching between the EV and diesel modes through a simple cabin switch (30), providing operational flexibility and efficiency.

[0027] According to Fig.1, the system incorporates significant modifications, starting with a chassis extension of 600 mm to 800 mm to accommodate the EV motor (20) and its dedicated components. The EV motor's structural support comes from the chassis extension, which is reinforced to account for the load of the motor and components. As seen in Fig.1, there is a hydraulic electrical mounting flange (80) to indicate a load-bearing portion capable of handling the weight of the EV motor (10).

[0028] This mounting flange (80) securely attaches the electric motor to the hydraulic pump, ensuring proper alignment and stability during operation. It also facilitates efficient torque transfer from the motor to the pump, thereby reducing wear and enhancing overall performance. The flange (80) ensures precise alignment between the motor and pump shafts, effectively mitigating vibrations and minimizing the risk of mechanical failures.

[0029] Additionally, the hydraulic electric mounting flange (80) streamlines the installation and removal process for motor-pump assemblies, simplifying maintenance and replacements. Its design accommodates specific motor-pump models, providing versatility and compatibility across various brands and configurations.

[0030] As seen in Fig.1, both the diesel engine (10) and EV motor (20) are equipped with their own hydraulic pumps (40, 50), to ensure separate functionality for both the diesel engine and the EV motor. Further non-return control valves (60) are provided for both the diesel engine (10) and the electric vehicle (20) to prevent the backflow of hydraulic oils to the hydraulic tank (120) and to ensure that the hydraulic oil always flows exclusively from an active pump, enabling the independent operation of either of the systems (10,20) without interference. This allows individual running of either EV Motor (20) or Diesel Engine (10). There is a control valve (120), positioned adjacent to the diesel engine, depicted in the Fig.1. The non-return control valves (60) serve a specific function in managing the hydraulic oil flow depending on the machine's operating mode. In Diesel Mode, the non-return control valve leading to the Electric Motor (20) remains closed, while the valve to the Diesel Engine (10) is open. Conversely, in EV Mode, the configuration is reversed i.e., the non-return control valve to the Diesel Engine (10) is closed, and the valve to the Electric Motor (20) is open.

[0031] Located near the diesel engine (10), there is the diesel tank (70) that stores the fuel necessary to power the engine. It is connected to the system through appropriate pipelines, ensuring a steady supply of fuel.
[0032] Referring back to Fig.1, at the top right, the hydraulic oil cooler operating at an optimum temperature of 1000C along with fans are installed to ensure the hydraulic fluids in the diesel engine (10) and electric motor (20) remain at an optimal temperature, supplementing the existing radiator and hydraulic oil cooler used by the diesel engine. Overheated hydraulic oil can reduce system efficiency and cause damage, so the cooler dissipates excess heat. The radiator (90) operating at an optimum temperature of 900C is also part of the cooling system, working in conjunction with the hydraulic oil cooler. It ensures that the engine and hydraulic systems operate within safe temperature limits. To safeguard the system during EV mode, a Current Protection Transformer (CPT) board (not shown in figure) is employed to protect against power fluctuations. Furthermore, a high-performance control panel (110) is integrated to regulate electricity inputs, prevent short circuits, and enhance operational reliability of the system.
[0033] According to Fig.1, the hybrid system allows the diesel engine (10) to operate utilizing its hydraulic pump (40) during diesel mode, while the EV motor, mounted on the extended chassis, operates its separate hydraulic pump (50) allowing flexibility to switch between power sources. The hybrid conversion system for diesel excavators integrates the electric vehicle (EV) motor alongside the existing diesel engine, mounted on an extended and reinforced chassis. This design enables efficient operation in both EV and Diesel modes, ensuring seamless transitions and flexibility in various operational scenarios.

[0034] The system employs separate hydraulic pumps (40,50) for the EV motor (20) and the diesel engine (10), allowing each to operate independently. The EV motor (20) drives its own hydraulic pump (50) to control excavator functions such as arm movement and digging, while the diesel engine (10) operates its hydraulic pump (40). The non-return valves (60) are incorporated to regulate hydraulic oil flow, ensuring oil flows only from the active pump, depending on the mode, and preventing backflow or mixing between the two systems. This independent mechanism allows both power sources to function without interfering with each other.
[0035] The cabin switch (30) enables the operator to effortlessly transition between EV Mode and Diesel Mode. This cabin switch allows for seamless switching based on operational needs, enhancing convenience and adaptability.

[0036] In EV mode, the excavator is powered through an external power supply through a cable connected to the EV motor (20). The diesel engine (10) is completely shut down, ensuring zero emissions and a quieter working environment. The EV motor (20) drives its hydraulic pump (50) to perform all excavator operations efficiently. To prevent overheating during extended use, an additional oil cooler is installed near the EV motor, maintaining optimal operating temperatures.

[0037] When operating in Diesel mode, the system functions like a standard diesel excavator. The diesel engine powers its hydraulic pump, while the EV motor remains inactive. This mode provides the flexibility of traditional excavator performance.
[0038] The system includes the CPT board that protects against electrical fluctuations, ensuring stable EV motor operation. A high-end control panel optimizes energy usage and manages smooth power delivery to the EV motor. It also provides protection against short circuits, enhancing the system's safety and reliability.

[0039] An additional oil cooler (100), positioned near to the EV motor (20), dissipates heat generated during EV mode. This ensures consistent motor performance and prevents overheating, even during prolonged operations. The hybrid conversion system offers numerous advantages, including the independent operation of the EV and diesel systems, which enhances both flexibility and reliability. The seamless switching capability via a cabin switch ensures operational convenience, allowing the operator to easily transition between modes based on requirements. Further, the need for large and costly battery packs is eliminated, reducing weight and maintenance. Instead, the invention excludes the use of power storage or regenerative devices, as it is directly connected to a power supply through a cable.
[0040] Enhanced cooling mechanisms and robust electrical protections contribute to improved system safety and longevity. Additionally, the zero-emission EV mode (20) significantly reduces environmental impact and noise pollution, while the Diesel mode (10) provides the dependable performance of traditional excavators.

[0041] The hybrid conversion system provides unparalleled flexibility, enabling seamless switching between EV and Diesel modes to suit diverse operational needs and work environments. The EV mode produces zero emissions, significantly reducing environmental impact, while also offering quieter operation to minimize noise pollution in urban or noise-sensitive areas. By eliminating the reliance on batteries and utilizing existing infrastructure, the system reduces initial investment and maintenance costs, ensuring lower overall operating expenses. The dual-mode system improves fuel efficiency, allowing EV mode to cut fuel consumption and Diesel mode to support extended operation without dependence on external power. Safety and reliability are enhanced through advanced electrical protections, such as the high-end control panel and CPT board. Additionally, the inclusion of a robust cooling system reduces wear and tear, extending the equipment’s operational lifespan.

[0042] The hybrid conversion system of diesel excavators addresses several key challenges by offering lower operating costs through reduced fuel dependency and improved energy efficiency. The system requires less maintenance due to fewer moving parts and features a modular design that simplifies servicing. These advantages lead to higher ROI by reducing costs and enhancing operational efficiency. Additionally, the hybrid system supports eco-friendly operations with lower emissions, quieter performance for better workplace conditions, and reduced reliance on specialized technicians, cutting service costs and minimizing downtime.

[0043] The hybrid conversion system is highly versatile and suitable for a wide range of applications. It is ideal for construction sites, particularly in urban or environmentally sensitive areas, where both traditional diesel and eco-friendly operations are required. The system's low-emission EV mode and quieter operation make it perfect for urban infrastructure projects and populated zones where minimizing noise and pollution is essential. In mining operations, the system offers flexibility to work in remote locations without power infrastructure while still providing a sustainable, low-emission alternative. Additionally, it is well-suited for landscaping and excavation projects, delivering efficient performance across varying soil conditions. For environmental remediation efforts, the system ensures compliance with strict regulations by reducing emissions and environmental impact. These features make it a reliable choice for diverse work environments requiring efficiency, flexibility, and eco-conscious operation.
, C , C , Claims:I/WE CLAIM:
1. A hybrid conversion system for a diesel machine, comprising:
an existing diesel engine (10) on a chassis;
an electric vehicle (EV) motor (20) mounted on an extension of the chassis, which is reinforced;
a first hydraulic pump (40) associated with the diesel engine;
a second hydraulic pump (50) associated with the EV motor;
non-return control valves (60) configured to prevent backflow of hydraulic oil and ensure flow exclusively from an active pump associated with the diesel engine or the EV motor;
a cabin switch (30) for seamlessly switching between diesel and electric modes of operation, wherein a hydraulic oil cooler (100) is positioned near the EV motor (20);
a Current Protection Transformer (CPT) board provided to protect against electrical power fluctuations; and
a high-performance control panel (110) is provided to regulate electricity inputs and to prevent short circuits in the EV motor (20).
2. The hybrid conversion system as claimed in claim 1, wherein the chassis is extended by 600 mm to 800 mm to accommodate the EV motor (20) and its components.

3. The hybrid conversion system as claimed in claim 1, comprising a hydraulic electrical motor mounting flange (80) configured to attach the EV motor (20) to the hydraulic pump (50) and install separate cooling mechanisms for the diesel engine (10) and EV motor (20).

4. The hybrid conversion system as claimed in claim 1, wherein the EV motor (20) is directly connected to a power supply through a cable.

5. The hybrid conversion system as claimed in claim 1, wherein: the system enables zero-emission operation in electric mode; and provides flexibility to switch between power sources based on operational requirements.

6. The hybrid conversion system as claimed in claim 1, wherein seamless conversion from the diesel engine (10) to EV (20) motor and back is enabled without requiring further equipment modifications or additional battery packs.

7. The hybrid conversion system as claimed in claim 1, wherein the machine is a diesel excavator.
8. A method of operating a hybrid conversion system for a diesel machine, the steps comprising of:
extending and reinforcing an existing chassis of a diesel engine (10);
mounting an EV motor (20) alongside the existing diesel engine;
installing separate hydraulic pumps (40, 50) for each power source;
implementing non-return control valves (60) to manage hydraulic oil flow;
adding a cabin switch (30) for mode transition;
integrating additional cooling and electrical protection systems; comprising
i. switching between diesel and electric modes via the cabin switch; and maintaining independent hydraulic pump operation for each power source; and
ii. powering the machine through an external power supply connected to the EV motor (20), in electric mode.

9. The method as claimed in claim 8, wherein the diesel engine (10) and electric vehicle motor (20) operate independently of each other.