DESC:FIELD OF THE INVENTION
The present disclosure relates to a hydraulic system and in particular, relates to systems and methods for operating at least one hydraulically-operated device of a vehicle.

BACKGROUND
Usually, heavy vehicles include a number of components that are hydraulically operated. Particularly, in case of recovery vehicles, they are required to recover disabled vehicles and machineries and transport them to a repair shop. For recovering such damaged machineries, recovery vehicles are typically equipped with multiple hydraulically-operated mechanisms or recovery aggregates. Table 1 illustrates few examples of such mechanisms.

Table 1
S No. Components Description
1 Main Winch Pulling of heavy disabled payloads - 50 tonne
2 Auxiliary Winch Handling smaller payloads - 3 tonne
3 Crane Picking and placing of Multiple Utility Assemblies - 20 tonne @ 3m
4 Dozer Stabilizing the base vehicle and ground preparation operations- 100 tonne anchorage
5 Suspension locking Stabilizing the vehicle during crane operation

Currently, such recovery aggregates are required to be operated in an open cycle configuration. As is generally known, in an open cycle configuration system, the hydraulic fluid is returned into a large unpressurized tank at the end of a circulation cycle. In case all the recovery aggregates are to be operated in the open cycle configuration, size of the hydraulic tank becomes very bulky for mobile applications. This is because dimensions of a hydraulic tank are generally determined based on a maximum flow rate. Moreover, for a rated shaft speed, gear pump was generating fixed displacement and catered to rated pressure setting. Accordingly, in order to meet different flow speeds, a Main Engine Power Take-Off Unit is required to be equipped with multiple pumps. Therefore, the existing open cycle hydraulic systems involve bulky hydraulic tanks, fixed displacement of pumps, and unavoidable power loss during idle condition.
Alternatively, such recovery aggregates may be operated in a closed cycle configuration. As is generally known, a closed cycle system is where the hydraulic fluid stays in one closed pressurized loop without returning to a main tank after each cycle. The existing closed cycle hydraulic systems involve the disadvantages of frequent maintenance, servicing, and replacement of spares.

SUMMARY
This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.
In an embodiment, a hybrid hydraulic system for operating at least one hydraulically-operated device of a vehicle is disclosed. The hybrid hydraulic system includes a main pump closed cycle coupled to an engine power shaft. The main pump closed cycle includes a first hydraulically-operated device of the vehicle and a first pump hydraulically coupled to the first hydraulically-operated device. The first pump is adapted to circulate a hydraulic fluid in at least one fluid line of the main pump closed cycle to operate the first hydraulically-operated device. The hybrid hydraulic system includes a main pump open cycle coupled to the engine power shaft. The main pump open cycle includes a second hydraulically-operated device of the vehicle and a second pump hydraulically coupled to the second hydraulically-operated device. The second pump is adapted to circulate a hydraulic fluid in at least one fluid line of the main pump open cycle to operate the second hydraulically-operated device. The hybrid hydraulic system includes a controller in communication with the main pump closed cycle and the main pump open cycle. The controller is adapted to receive an instruction to operate at least one of the first hydraulically-operated device and the second hydraulically-operated device. The controller is adapted to control an operation of the first pump and the second pump to circulate the hydraulic fluid to operate the first hydraulically-operated device and the second hydraulically-operated device, respectively, based on the instruction.
In another embodiment of the present disclosure, a method of controlling circulation of a hydraulic fluid in a hybrid hydraulic system of a vehicle is disclosed. The method includes receiving, by a controller, an instruction to operate one of a first hydraulically-operated device and a second hydraulically-operated device of the vehicle. The first hydraulically-operated device and a second hydraulically-operated device are in a main pump closed cycle and a main pump open cycle, respectively. The method includes controlling, by the controller, an operation of a first pump of the main pump closed cycle, to circulate a hydraulic fluid in at least one fluid line of the main pump closed cycle to operate the first hydraulically-operated device, when the instruction is to operate the first hydraulically-operated device. The method includes controlling, by the controller, an operation of a second pump of the main pump open cycle, to circulate the hydraulic fluid in at least one fluid line of the main pump open cycle to operate the second hydraulically-operated device, when the instruction is to operate the second hydraulically-operated device.
To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Figure 1 illustrates a block diagram of a hybrid hydraulic system for operating at least one hydraulically-operated device of a vehicle, according to an embodiment of the present disclosure;
Figure 2 illustrates a block diagram of the hybrid hydraulic system depicting powering of a main winch from a Main Engine Power Take Off Unit of the vehicle, according to an embodiment of the present disclosure;
Figure 3 illustrates a block diagram of the hybrid hydraulic system depicting powering of an auxiliary winch from the Main Engine Power Take Off Unit, according to an embodiment of the present disclosure;
Figure 4 illustrates a block diagram of the hybrid hydraulic system depicting powering of a crane from the Main Engine Power Take Off Unit, according to an embodiment of the present disclosure;
Figure 5 illustrates a block diagram of the hybrid hydraulic system depicting powering of a dozer from the Main Engine Power Take Off Unit, according to an embodiment of the present disclosure;
Figure 6 illustrates a block diagram of the hybrid hydraulic system depicting powering of a suspension lock from the Main Engine Power Take Off Unit, according to an embodiment of the present disclosure;
Figure 7 illustrates a block diagram of the hybrid hydraulic system depicting powering of the auxiliary winch from an external power source, according to an embodiment of the present disclosure;
Figure 8 illustrates a block diagram of the hybrid hydraulic system depicting powering of the crane from the external power source, according to an embodiment of the present disclosure;
Figure 9 illustrates a block diagram of the hybrid hydraulic system depicting powering of the dozer from the external power source, according to an embodiment of the present disclosure;
Figure 10 illustrates a block diagram of the hybrid hydraulic system depicting powering of the suspension lock from the external power source, according to an embodiment of the present disclosure; and
Figure 11 illustrates a flow chart depicting a method for operating at least one hydraulically-operated device of the vehicle, according to an embodiment of the present disclosure.
Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.
Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
The terms "comprises", "comprising", or any other variations thereof, are intended to cover a nonexclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or subsystems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.
It should be understood at the outset that although illustrative implementations of the embodiments of the present disclosure are illustrated below, the present invention may be implemented using any number of techniques, whether currently known or in existence. The present disclosure should in no way be limited to the illustrative implementations, drawings, and techniques illustrated below, including the exemplary design and implementation illustrated and described herein, but may be modified within the scope of the appended claims along with their full scope of equivalents.
The term “some” as used herein is defined as “none, or one, or more than one, or all.” Accordingly, the terms “none,” “one,” “more than one,” “more than one, but not all” or “all” would all fall under the definition of “some.” The term “some embodiments” may refer to no embodiments or to one embodiment or to several embodiments or to all embodiments. Accordingly, the term “some embodiments” is defined as meaning “no embodiment, or one embodiment, or more than one embodiment, or all embodiments.”
The terminology and structure employed herein is for describing, teaching and illuminating some embodiments and their specific features and elements and does not limit, restrict or reduce the spirit and scope of the claims or their equivalents.
Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements presented in the attached claims. Some embodiments have been described for the purpose of illuminating one or more of the potential ways in which the specific features and/or elements of the attached claims fulfil the requirements of uniqueness, utility and non-obviousness.
Use of the phrases and/or terms such as but not limited to “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or variants thereof do NOT necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and/or elements may be described herein in the context of only a single embodiment, or alternatively in the context of more than one embodiment, or further alternatively in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.
Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
For the sake of clarity, the first digit of a reference numeral of each component of the present disclosure is indicative of the Figure number, in which the corresponding component is shown. For example, reference numerals starting with digit “1” are shown at least in Figure 1. Similarly, reference numerals starting with digit “2” are shown at least in Figure 2.
Figure 1 illustrates a block diagram of a hybrid hydraulic system 100 for operating at least one hydraulically-operated device of a vehicle, according to an embodiment of the present disclosure. For the sake of ease of readability, the hybrid hydraulic system 100 may hereinafter interchangeably be referred to as the system 100. In an embodiment, the system 100 may be implemented in a recovery vehicle having one or more hydraulically-operated recovery aggregates. In an embodiment, the recovery vehicle may be an all-terrain tracked recovery vehicle. As would be appreciated by a person skilled in the art, the system 100 may be implemented in any vehicle having one or more hydraulically-operated devices, without departing from the scope of the present disclosure.
In the illustrated embodiment, the system 100 is adapted to control operation of two hydraulically-operated devices 102, namely, a first hydraulically-operated device 102-1 and a second hydraulically-operated device 102-2. The first hydraulically-operated device 102-1 and the second hydraulically-operated device 102-2 are hereinafter interchangeably referred to as the first device 102-1 and the second device 102-2, respectively.
In the illustrated embodiment, the system 100 may include, but is not limited to, a main pump closed cycle 104, a main pump open cycle 106, and a controller 108 in communication with the main pump closed cycle 104 and the main pump open cycle 106. The main pump closed cycle 104 and the main pump open cycle 106 may be coupled to an engine power shaft. Particularly, the main pump closed cycle 104 and the main pump open cycle 106 may be coupled in tandem configuration on a single shaft of a main engine power take off unit. By the term “tandem configuration”, it is implied that the main pump closed cycle 104 and the main pump open cycle 106 are coupled with the same single shaft and are activated and deactivated together.
The main pump closed cycle 104 may include, but is not limited to, the first device 102-1 and a first pump 110 hydraulically coupled to the first device 102-1. In an embodiment, the first pump 110 may include an integrated charge booster pump. The first pump 110 may be capable of ensuring continuous supply of pressurized oil in fluid lines and proportional electro-hydraulic solenoid actuation, which will ensure seamless variation of flow and pressure. The first pump 110 may be adapted to circulate a hydraulic fluid in at least one fluid line of the main pump closed cycle 104 to operate the first device 102-1. The main pump closed cycle 104 may be in communication with the controller 108.
Further, the main pump open cycle 106 may include, but is not limited to, the second device 102-2 and a second pump 112 hydraulically coupled to the second device 102-2. In an embodiment, the second pump 112 may be an axial piston variable displacement pump. The second pump 112 may have load sensing capabilities capable of facilitating a fluid flow in correlation with the requirement. The second pump 112 may be adapted to circulate the hydraulic fluid in at least one fluid line of the main pump open cycle 106 to operate the second device 102-2. In an embodiment, the main pump open cycle 106 may further include a swash plate operation based on the load sensing feedback pilot line pressure. The main pump open cycle 106 may be in communication with the controller 108.
The controller 108 may be adapted to receive an instruction to operate at least one of the first device 102-1 and the second device 102-2. In an embodiment, the controller 108 may include a processor (not shown), memory (not shown), modules (not shown), and data (not shown). The modules and the memory may be coupled to the processor. The processor may be a single processing unit or a number of units, all of which could include multiple computing units. The processor may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and/or any devices that manipulate signals based on operational instructions. Among other capabilities, the processor is configured to fetch and execute computer-readable instructions and data stored in the memory.
The memory may include any non-transitory computer-readable medium known in the art including, for example, volatile memory, such as static random access memory (SRAM) and dynamic random access memory (DRAM), and/or non-volatile memory, such as read-only memory (ROM), erasable programmable ROM, flash memories, hard disks, optical disks, and magnetic tapes.
The modules, amongst other things, include routines, programs, objects, components, data structures, etc., which perform particular tasks or implement data types. The modules may also be implemented as, signal processor(s), state machine(s), logic circuitries, and/or any other device or component that manipulate signals based on operational instructions.
Further, the modules can be implemented in hardware, instructions executed by a processing unit, or by a combination thereof. The processing unit can comprise a computer, a processor, such as the processor, a state machine, a logic array or any other suitable devices capable of processing instructions. The processing unit can be a general-purpose processor which executes instructions to cause the general-purpose processor to perform the required tasks or, the processing unit can be dedicated to perform the required functions. In another aspect of the present disclosure, the modules may be machine-readable instructions which, when executed by a processor/processing unit, perform any of the described functionalities.
Based on the instruction, the controller 108 may be adapted to control an operation of the first pump 110 and the second pump 112 to circulate the hydraulic fluid to operate the first device 102-1 and the second device 102-2, respectively.
In an embodiment, the system 100 may also include an external power source 114 and an auxiliary pump open cycle 116 operably coupled to the external power source 114. The auxiliary pump open cycle 116 may include, but is not limited to, the second device 102-2 and an auxiliary pump 118 hydraulically coupled to the second device 102-2. The auxiliary pump 118 may be of reduced flow rate capacity. The auxiliary pump 118 may be adapted to load sensing capabilities that will facilitate flow proportional to the requirement. In an embodiment, the auxiliary pump 118 may be an axial piston variable displacement pump. The auxiliary pump 118 may be adapted to circulate the hydraulic fluid in at least one fluid line of the auxiliary pump open cycle 116 to operate the second device 102-2. The auxiliary pump open cycle 116 may be in communication with the controller 108. The controller 108 may be adapted to control an operation of the auxiliary pump 118 to circulate the hydraulic fluid to operate the second device 102-2. The system 100 facilitates powering of the hydraulically-operated devices by the external power source 114 of reduced capacity to ensure system redundancy. In an embodiment, the first pump 110, the second pump 112, and the auxiliary pump 118 are coupled to a hydraulic tank 122.
In an embodiment, the system 100 may further include a load sensing selector valve 120 operably coupled to the second pump 112 and the auxiliary pump 118. The load sensing selector valve 120 may be adapted to control a flow of the hydraulic fluid flowing towards the second device 102-2 from the second pump 112 and the auxiliary pump 118, based at least on an operational status of the external power source 114 supplying power to the load sensing selector valve 120. In an embodiment, when the operational state of the external power source 114 is active, the load sensing selector valve 120 may allow the auxiliary pump 118 to circulate the hydraulic fluid to operate the second device 102-2. Further, the load sensing selector valve 120 may be capable of facilitating unloading of load sensing lines of inactive hydraulically-operated devices 102 and activating interfacing of load sensing lines of active hydraulically-operated devices 102 with the second pump 112.
In an embodiment, the system 100 may be implemented in a recovery vehicle having multiple recovery aggregates adapted to operate hydraulically. In an embodiment, the recovery aggregates may include, but are not limited to, a winch, an auxiliary winch, a crane, a dozer, and a suspension lock. From the perspective of the detailed description of Figure 1, the winch may be understood to be the first device 102-1. Further, each of the auxiliary winch, the crane, the dozer, and the suspension lock may be understood to be the second device 102-2. Also, in an embodiment, instead of having one controller 108 for operating all the recovery aggregates and the associated components, the system 100 may include separate controller for each of the recover aggregate, as illustrated in subsequent embodiments, without departing from the scope of the present disclosure. The constructional and operational characteristics of the separate controllers may be the same as that of the controller 108.
Figure 2 illustrates a block diagram of the system 100 depicting powering of the main winch 102-1 from a Main Engine Power Take Off Unit 202 of the vehicle, according to an embodiment of the present disclosure. In the present embodiment, the main engine is turned ON, the main pump closed cycle 104 and the main pump open cycle 106 may receive the drive from the main engine Power Take-Off Unit 202. Further, the external power source 114 is in OFF condition. The load sensing selector valve 120 will be in OFF condition as the external power source 114 is OFF. The shaft of the main pump open cycle 106 may also rotate at the same speed as it is mounted on the same shaft. Other recovery aggregates, such as the auxiliary winch 102-2, the crane 102-2, and the dozer 102-2, are turned OFF by the controller 108-2, the controller 108-3, the controller 108-4, and the controller 108-5, respectively. The main pump open cycle 106 may run at no load condition with minimum opening of the swash plate. The controller 108-2 may control the electro-hydraulic proportional solenoid of the main pump closed cycle 104. Accordingly, the first pump 110 may generate the flow proportional to the requirement of the controller 108-1.
Figure 3 illustrates a block diagram of the system 100 depicting powering of the auxiliary winch 102-2 from the main engine Power Take Off Unit 202, according to an embodiment of the present disclosure. In an embodiment, the main engine is turned ON, the main pump closed cycle 104 and the main pump open cycle 106 may receive the drive from the main engine Power Take-Off Unit 202. Further, the external power source 114 is in OFF condition. The load sensing selector valve 120 will be in OFF condition as the external power source 114 is OFF. The shaft of the main pump open cycle 106 may also rotate at the same speed as it is mounted on the same shaft. Other recovery aggregates, such as the winch 102-1, the crane 102-2, and the dozer 102-2, are turned OFF by the controller 108-1, the controller 108-3, the controller 108-4, and the controller 108-5, respectively. The main pump closed cycle 106 may run at no load condition with minimum opening of the swash plate. The controller 108-2 may control the main pump open cycle 106. Accordingly, the second pump 112 may generate the flow proportional to the requirement of the controller 108-2.
Figure 4 illustrates a block diagram of the system 100 depicting powering of the crane 102-2 from the main engine Power Take Off Unit 202, according to an embodiment of the present disclosure. In an embodiment, the main engine is turned ON, the main pump closed cycle 104 and the main pump open cycle 106 may receive the drive from the main engine Power Take-Off Unit 202. Further, the external power source 114 is in OFF condition. The load sensing selector valve 120 will be in OFF condition as the external power source 114 is OFF. The shaft of the main pump open cycle 106 may also rotate at the same speed as it is mounted on the same shaft. Other recovery aggregates, such as the main winch 102-1, the auxiliary winch 102-2, the dozer 102-2, and the suspension lock 102-2 may be turned OFF by the respective controllers 108. The main pump closed cycle 104 may run at no load condition with minimum opening of the swash plate. The controller 108-3 may control the main pump open cycle 106. The second pump 112 may generate the flow proportional to the requirement of the controller 108-3.
Figure 5 illustrates a block diagram of the system 100 depicting powering of the dozer 102-2 from the main engine Power Take Off Unit 202, according to an embodiment of the present disclosure. In an embodiment, the main engine is turned ON, the main pump closed cycle 104 and the main pump open cycle 106 may receive the drive from the main engine Power Take-Off Unit 202. Further, the external power source 114 is in OFF condition. The load sensing selector valve 120 will be in OFF condition as the external power source 114 is OFF. The shaft of the main pump open cycle 106 may also rotate at the same speed as it is mounted on the same shaft. Other recovery aggregates, such as the main winch 102-1, the auxiliary winch 102-2, the crane 102-2, and the suspension lock 102-2 are turned OFF by the respective controllers 108. The main pump closed cycle 104 may run at no load condition with minimum opening of the swash plate. The controller 108-4 may control the main pump open cycle 106. The second pump 112 may generate the flow proportional to the requirement of the controller 108-4.
Figure 6 illustrates a block diagram of the system 100 depicting powering of the suspension lock 102-2 from the main engine Power Take Off Unit 202, according to an embodiment of the present disclosure. In an embodiment, the main engine is turned ON, the main pump closed cycle 104 and the main pump open cycle 106 may receive the drive from the main engine Power Take-Off Unit 202. Further, the external power source 114 is in OFF condition. The load sensing selector valve 120 will be in OFF condition as the external power source 114 is OFF. The shaft of the main pump open cycle 106 may also rotate at the same speed as it is mounted on the same shaft. Other recovery aggregates, such as the main winch 102-1, the auxiliary winch 102-2, the crane 102-2, and the dozer 102-2 are turned OFF by the respective controllers 108. The main pump closed cycle 104 may run at no load condition with minimum opening of the swash plate. The controller 108-5 may control the main pump open cycle 106. The second pump 112 may generate the flow proportional to the requirement of the controller 108-5.
Figure 7 illustrates a block diagram of the system 100 depicting powering of the auxiliary winch 102-2 from the external power source 114, according to an embodiment of the present disclosure. In an embodiment, the main engine is in OFF condition and therefore, no drive is being received from the main engine Power Take-Off Unit 202. The external power source 114 may be turned ON. The low sensing selector valve 120 may be turned ON based on the input from external power source 114. The shaft of the auxiliary pump open cycle 116 may receive the drive from the external power source 114. Other recovery aggregates, such as the main winch 102-1, the crane 102-2, the dozer 102-2, and the suspension lock 102-2, are turned OFF by the respective controllers 108. The controller 108-2 may control the auxiliary pump open cycle 116. The second pump 112 may generate the flow proportional to the requirement of the controller 108-2.
Figure 8 illustrates a block diagram of the system 100 depicting powering of the crane 102-2 from the external power source 114, according to an embodiment of the present disclosure. In an embodiment, the main engine is in OFF condition and therefore, no drive is being received from the main engine Power Take-Off Unit 202. The external power source 114 may be turned ON. The low sensing selector valve 120 may be turned ON based on the input from external power source 114. The shaft of the auxiliary pump open cycle 116 may receive the drive from the external power source 114. Other recovery aggregates, such as the main winch 102-1, the auxiliary winch 102-2, the dozer 102-2, and the suspension lock 102-2 are turned OFF by the respective controllers 108. The controller 108-3 may control the auxiliary pump open cycle 116. The second pump 112 may generate the flow proportional to the requirement of the controller 108-3.
Figure 9 illustrates a block diagram of the system 100 depicting powering of the dozer 102-2 from the external power source 114, according to an embodiment of the present disclosure. In an embodiment, the main engine is in OFF condition and therefore, no drive is being received from the main engine Power Take-Off Unit 202. The external power source 114 may be turned ON. The low sensing selector valve 120 may be turned ON based on the input from external power source 114. The shaft of the auxiliary pump open cycle 116 may receive the drive from the external power source 114. Other recovery aggregates, such as the main winch 102-1, the auxiliary winch 102-2, the crane 102-2, and the suspension lock 102-2 are turned OFF by the respective controllers 108. The controller 108-4 may control the auxiliary pump open cycle 116. The second pump 112 may generate the flow proportional to the requirement of the controller 108-4.
Figure 10 illustrates a block diagram of the system 100 depicting powering of the suspension lock 102-2 from the external power source 114, according to an embodiment of the present disclosure. In an embodiment, the main engine is in OFF condition and therefore, no drive is being received from the main engine Power Take-Off Unit 202. The external power source 114 may be turned ON. The low sensing selector valve 120 may be turned ON based on the input from external power source 114. The shaft of the auxiliary pump open cycle 116 may receive the drive from the external power source 114. Other recovery aggregates, such as the main winch 102-1, the auxiliary winch 102-2, the crane 102-2, and the dozer 102-2 are turned OFF by the respective controllers 108. The controller 108-5 may control the auxiliary pump open cycle 116. The second pump 112 may generate the flow proportional to the requirement of the controller 108-5.
Figure 11 illustrates a flow chart depicting a method 1100 for operating at least one hydraulically-operated device 102 of the vehicle, according to an embodiment of the present disclosure. In an embodiment, the method 1100 may be a computer-implemented method 1100. Further, for the sake of brevity, details of the present disclosure that are explained in details in the description of Figure 1, Figure 2, Figure 3, Figure 4, Figure 5, Figure 6, Figure 7, Figure 8, Figure 9, and Figure 10 are not explained in detail in the description of Figure 11.
At a block 1102, the method 1100 includes receiving an instruction to operate at least one of the first device 102-1 and the second device 102-2. The first device 102-1 and the second device 102-2 are in the main pump closed cycle 104 and the main pump open cycle 106, respectively. In an embodiment, the controller 108 may receive the instruction.
At a block 1104, the method 1100 includes controlling an operation of the first pump 110 to circulate the hydraulic fluid in at least one fluid line of the main pump closed cycle 104 to operate the first device 102-1, when the instruction is to operate the first device 102-1. In an embodiment, the controller 108 may control the operation of the first pump 110.
At a block 1106, the method 1100 includes controlling an operation of the second pump 112 to circulate the hydraulic fluid in at least one fluid line of the main pump open cycle 106 to operate the second device 102-2, when the instruction is to operate the second device 102-2. In an embodiment, the controller 108 may control the operation of the second pump 102.
In an embodiment, the method 1100 may include receiving an instruction to operate the second device 102-2. Based on the instruction, the method 1100 may include controlling an operation of the auxiliary pump 118 to circulate the hydraulic fluid for operating the second device 102-2.
In an embodiment, the method 1100 may include receiving an instruction to operate the second device 102-2. The method 1100 may then include controlling a flow of the hydraulic fluid flowing towards the second device 102-2 from the second pump 112 and the auxiliary pump 118, based at least on an operational status of the external power source 114 supplying power to the load sensing selector valve 120.
As would be gathered, the present disclosure relates to the hybrid hydraulic system 100 and the method 1100 that offer a comprehensive approach for operating at least one hydraulically-operated device 102 of a vehicle. Owing to the present disclosure, multiple open cycle hydraulic aggregates and closed cycle aggregates can be operated seamlessly. This disclosure also provides flexibility to operate hydraulic aggregates at reduced speeds, in case of main prime mover failure. Tandem pump configuration in the hybrid hydraulic system 100 facilitates tapping single power output from the prime mover thereby improving the space utilization inside the powerpack compartment.
The hybrid hydraulic system 100 facilitates optimum sizing of hydraulic tank 122 with reduced oil quantity, reduction in overall weight, space utilization inside the hull structure, and optimum utilization of hydraulic power. This disclosure also provides enhanced flexibility to operate hydraulic aggregates from auxiliary power unit at reduced speeds. The hybrid hydraulic system 100 is capable of handling variable flows of 20 l/min - 260 l/min and pressures of 14 bar - 360 bar on mobile platforms operating in extreme hostile environment. Therefore, the present disclosure offers the hybrid hydraulic system 100 and the method 1100 that are simple, easy to install, maintain and operate, efficient, and economical.
While specific language has been used to describe the present disclosure, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein. The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment.
,CLAIMS:We Claim:

1. A hybrid hydraulic system (100) for operating at least one hydraulically-operated device (102) of a vehicle, the hybrid hydraulic system (100) comprising:
a main pump closed cycle (104) coupled to an engine power shaft and comprising:
a first hydraulically-operated device (102-1) of the vehicle; and
a first pump (110) hydraulically coupled to the first hydraulically-operated device (102-1) and adapted to circulate a hydraulic fluid in at least one fluid line of the main pump closed cycle (104) to operate the first hydraulically-operated device (102-1); and
a main pump open cycle (106) coupled to the engine power shaft and comprising:
a second hydraulically-operated device (102-2) of the vehicle; and
a second pump (112) hydraulically coupled to the second hydraulically-operated device (102-2) and adapted to circulate a hydraulic fluid in at least one fluid line of the main pump open cycle (106) to operate the second hydraulically-operated device (102-2); and
a controller (108) in communication with the main pump closed cycle (104) and the main pump open cycle (106), the controller (108) adapted to:
receive an instruction to operate at least one of the first hydraulically-operated device (102-1) and the second hydraulically-operated device (102-2); and
control an operation of the first pump (110) and the second pump (112) to circulate the hydraulic fluid to operate the first hydraulically-operated device (102-1) and the second hydraulically-operated device (102-2), respectively, based on the instruction.

2. The hybrid hydraulic system (100) as claimed in claim 1 comprising:
an external power source (114); and
an auxiliary pump open cycle (116) operably coupled to the external power source (114) and comprising:
the second hydraulically-operated device (102-2); and
an auxiliary pump (118) hydraulically coupled to the second hydraulically-operated device (102-2) and adapted to circulate a hydraulic fluid in at least one fluid line of the auxiliary pump open cycle (116) to operate the second hydraulically-operated device (102-2); and
the controller (108) in communication with the auxiliary pump open cycle (116) and adapted to control an operation of the auxiliary pump (118) to circulate the hydraulic fluid to operate the second hydraulically-operated device (102-2).

3. The hybrid hydraulic system (100) as claimed in claim 2 comprising a load sensing selector valve (120) operably coupled to the second pump (112) and the auxiliary pump (118) and adapted to control a flow of the hydraulic fluid flowing towards the second hydraulically-operated device (102-2) from the second pump (112) and the auxiliary pump (118), based at least on an operational status of the external power source (114) supplying power to the load sensing selector valve (120).

4. The hybrid hydraulic system (100) as claimed in claim 1, wherein the first hydraulically-operated device (102-1) is a winch.

5. The hybrid hydraulic system (100) as claimed in claim 1, wherein the second hydraulically-operated device (102-2) comprises one of an auxiliary winch, a crane, a dozer, and a suspension locking mechanism.

6. The hybrid hydraulic system (100) as claimed in claim 1, wherein the first pump (110) is an integrated charge booster pump.

7. The hybrid hydraulic system (100) as claimed in claim 1, wherein the second pump (112) and the third pump (118) are axial piston variable displacement pumps.

8. A method (1100) of controlling circulation of a hydraulic fluid in a hybrid hydraulic system (100) of a vehicle, the method comprising:
receiving, by a controller (108), an instruction to operate at least one of a first hydraulically-operated device (102-1) and a second hydraulically-operated device (102-2), wherein the first hydraulically-operated device (102-1) and the second hydraulically-operated device (102-2) are in a main pump closed cycle (104) and a main pump open cycle (106), respectively;
controlling, by the controller (108), an operation of a first pump (110) of the main pump closed cycle (104), to circulate a hydraulic fluid in at least one fluid line of the main pump closed cycle (104) to operate the first hydraulically-operated device (102-1), when the instruction is to operate the first hydraulically-operated device (102-1); and
controlling, by the controller (108), an operation of a second pump (112) of the main pump open cycle (106), to circulate the hydraulic fluid in at least one fluid line of the main pump open cycle (106) to operate the second hydraulically-operated device (102-2), when the instruction is to operate the second hydraulically-operated device (102-2).
9. The method (1100) as claimed in claim 8 comprising:
receiving, by the controller (108), an instruction to operate the second hydraulically-operated device (102-2); and
controlling, by the controller (108), an operation of an auxiliary pump (118) to circulate the hydraulic fluid for operating the second hydraulically-operated device (102-2).

10. The method (1100) as claimed in claim 8 comprising:
receiving, by the controller (108), an instruction to operate the second hydraulically-operated device (102-2); and
controlling, by a load sensing selector valve (120), a flow of the hydraulic fluid flowing towards the second hydraulically-operated device (102-2) from the second pump (112) and an auxiliary pump (118), based at least on an operational status of an external power source (114) supplying power to the load sensing selector valve (120).