CN216552169U - Excavator and hydraulic drive electric control system thereof - Google Patents
Excavator and hydraulic drive electric control system thereof Download PDFInfo
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- CN216552169U CN216552169U CN202122974705.1U CN202122974705U CN216552169U CN 216552169 U CN216552169 U CN 216552169U CN 202122974705 U CN202122974705 U CN 202122974705U CN 216552169 U CN216552169 U CN 216552169U
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Abstract
The utility model discloses an excavator and a hydraulic drive electric control system thereof, wherein the hydraulic drive electric control system comprises: the executing assembly is provided with a plurality of executing mechanisms, and each executing mechanism is supplied with oil by at least one output oil way; the digital pump assembly is provided with at least two output oil ways for supplying oil to the execution assembly; and the control assembly is used for controlling the execution assembly and the digital pump assembly to act so as to realize the oil pressure change of the output oil circuit. The hydraulic drive electric control system provided by the utility model can realize different combinations by controlling the two output oil ways in the using process so as to provide hydraulic oil with different pressures for different actuating mechanisms; therefore, each actuator can obtain a separate pump source, the function of a pump-actuator is realized, and the arrangement of the digital pump assembly can reduce the installation size of the hydraulic drive electric control system.
Description
Technical Field
The utility model relates to the technical field of hydraulic drive, in particular to a hydraulic drive electric control system. In addition, the utility model also relates to an excavator comprising the hydraulic drive electric control system.
Background
The hydraulic system of the excavator comprises a single-pump double-pump LS system, a double-pump negative flow and positive flow system, a main valve loop of a medium-sized hydraulic excavator forms Negative Flow Control (NFC) in the last 80 th century from the initial throttling control, load sensing control (LS or LUDV) and Positive Flow Control (PFC) are developed in the last 90 th century, and electronically-controlled or hydraulically-controlled positive flow control (HPC) and near-term conceptual electro-hydraulic proportional control are formally formed in 2000, such as: the ECOVA (double-valve-core split type bus electric proportional control), the EFM (electric proportional flow matching control), the VBO (virtual flow distribution control), the EPC (electronic control positive flow control) and the like have the intelligent flow priority distribution function of composite actions, and are the current development situation of the liquid drive electric control system of the excavator at present.
In the prior art, the excavator operation is a typical application of multi-action compounding, and one pump with multiple actuating mechanisms inevitably causes large pressure loss and poor operability required by the compounding action harmony; the existing three-pump system has poor capability with multiple functions and weak electric control adaptability for intelligent requirements; one pump-one actuator, with a multi-pump arrangement, results in large installation size and increased cost.
In summary, how to reduce the installation size of the hydraulic drive electric control system while implementing one pump-actuator is an urgent problem to be solved by those skilled in the art.
SUMMERY OF THE UTILITY MODEL
In view of the above, an object of the present invention is to provide a hydraulic drive electronic control system, in the using process, a digital pump assembly outputs at least two output oil paths for supplying oil to an execution assembly, and in the process of supplying oil to a single execution mechanism, different combinations can be realized by controlling the two output oil paths to supply hydraulic oil with different pressures to different execution mechanisms; each actuating mechanism can obtain an independent pump source, and the function of one pump and one actuating mechanism is realized; and the digital pump assembly can reduce the installation size of the liquid drive electric control system.
Another object of the utility model is to provide an excavator comprising the above hydraulic drive electric control system.
In order to achieve the above purpose, the utility model provides the following technical scheme:
a fluid driven electrical control system comprising:
the executing assembly is provided with a plurality of executing mechanisms, and the single executing mechanism is supplied with oil by at least one path of output oil circuit;
the digital pump assembly is provided with at least two output oil ways for supplying oil to the execution assembly;
the control assembly is used for controlling the actions of the execution assembly and the digital pump assembly so as to realize the oil pressure change of the output oil circuit;
the execution assembly and the digital pump assembly are connected with the control assembly.
Preferably, the executing assembly comprises a rotary executing mechanism and a plurality of movable executing mechanisms, and the output oil path comprises a rotary oil supply path for supplying oil to the rotary executing mechanism and at least two movable oil supply paths for supplying oil to the movable executing mechanisms.
Preferably, the control assembly is provided with a CAN bus for controlling the rotating speed of the rotary actuating mechanism so as to control the rotary actuating mechanism to be in different rotating speeds under different working conditions.
Preferably, the mobile oil supply circuit is provided with a mobile oil supply branch for supplying oil to a single mobile actuating mechanism, and any mobile oil supply branch is provided with a branch electromagnetic valve for controlling the opening and closing of the branch electromagnetic valve;
the rotary oil supply oil path is provided with a rotary oil supply electromagnetic valve for controlling the opening and the closing of the rotary oil supply electromagnetic valve;
the branch solenoid valve and the rotary oil supply solenoid valve are connected with the control assembly.
Preferably, the branch solenoid valve and the rotary oil supply solenoid valve are both two-position two-way solenoid valves.
Preferably, the digital pump assembly includes a first digital pump and a second digital pump, and the output of the first digital pump has one output oil path, and the output of the second digital pump has two output oil paths.
Preferably, the flow rate of the output oil passage of the first digital pump is controlled by a plurality of first plungers;
the flow of one of the output oil paths of the second digital pump is controlled by a plurality of second plungers, and the flow of the other output oil path of the second digital pump is controlled by a plurality of third plungers.
Preferably, the first digital pump includes a plurality of first electromagnetic valves, and the first electromagnetic valves are arranged in one-to-one correspondence with the first plungers to control the number of the first plungers connected to the output oil path of the first digital pump;
the first solenoid valve is connected with the control assembly.
Preferably, the second digital pump includes a plurality of second electromagnetic valves and a plurality of third electromagnetic valves, and the second electromagnetic valves are arranged in one-to-one correspondence with the second plungers to control the number of the second plungers accessed to the corresponding output oil paths of the second digital pump;
the third electromagnetic valves are arranged in one-to-one correspondence with the third plungers so as to control the number of the third plungers accessed to the corresponding output oil passages of the second digital pump;
the second solenoid valve and the third solenoid valve are connected with the control assembly.
An excavator comprises the hydraulic drive electric control system.
In the process of using the liquid drive electric control system provided by the utility model, the control assembly controls the action of the digital pump assembly to realize the control on the flow and the oil pressure of an output oil way of the digital pump assembly, and the control assembly controls the action of the execution assembly to realize the control on the oil supply pressure of the execution mechanism; and because a single actuating mechanism is supplied with oil by at least one output oil path, hydraulic control on different output oil paths is combined with oil pressure control on the oil inlet end of the actuating mechanism, and hydraulic oil with different pressures can be supplied to different actuating mechanisms.
Compared with the prior art, the hydraulic drive electric control system provided by the utility model can realize different combinations by controlling the two output oil paths in the use process so as to provide different hydraulic oil with different pressures for different actuating mechanisms; therefore, each actuator can obtain a separate pump source, the function of a pump-actuator is realized, and the arrangement of the digital pump assembly can reduce the installation size of the hydraulic drive electric control system. The hydraulic drive electric control system provided by the utility model can well solve the problems of large composite action pressure loss, poor operability, large installation size and increased cost in the prior art, and achieves the effects of strong multi-working condition adaptability, different accessory pressures, strong flow matching capability, good composite action operability, safety, reliability, energy conservation and high efficiency.
In addition, the utility model also provides an excavator comprising the liquid drive electric control system.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a schematic structural diagram of an embodiment of a liquid drive electronic control system provided in the present application.
In fig. 1:
the hydraulic control system comprises an execution assembly 1, a mobile execution mechanism 11, a rotary execution mechanism 12, a branch electromagnetic valve 13, a rotary oil supply electromagnetic valve 14, a digital pump assembly 2, a first digital pump 21, a first plunger 211, a first electromagnetic valve 212, a first mobile oil supply path 213, a second digital pump 22, a second plunger 221, a third plunger 222, a second electromagnetic valve 223, a third electromagnetic valve 224, a second mobile oil supply path 225, a rotary oil supply path 226, a control assembly 3 and an oil return path 4.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The core of the utility model is to provide a hydraulic drive electric control system, in the using process, at least two output oil paths for supplying oil to an execution assembly are output by a digital pump assembly, and in the process of supplying oil to a single execution mechanism, different combinations can be realized by controlling two output oil paths so as to supply hydraulic oil with different pressures to different execution mechanisms; therefore, each actuator can obtain a separate pump source, and the function of a pump-actuator is realized. And the digital pump assembly can reduce the installation size of the liquid drive electric control system. The other core of the utility model is to provide an excavator comprising the hydraulic drive electric control system.
Please refer to fig. 1.
This embodiment discloses a hydraulic drive electrical system, includes:
the actuating assembly 1 is provided with a plurality of actuating mechanisms, and a single actuating mechanism is supplied with oil by at least one output oil path;
the digital pump assembly 2 is provided with at least two output oil paths for supplying oil to the execution assembly 1;
the control assembly 3 is used for controlling the actions of the execution assembly 1 and the digital pump assembly 2 so as to realize the oil pressure change of an output oil path;
the execution assembly 1 and the digital pump assembly 2 are both connected with the control assembly 3.
The control component 3 can be a controller, a plc control device, etc., which is determined according to actual conditions.
The number of the digital pumps of the digital pump assembly 2 can be set according to actual conditions, and is determined according to the actual conditions, which is not described herein.
The actuator in the actuator assembly 1 may be a moving structure or a rotating structure, which is determined according to actual conditions.
In the process of using the liquid drive electric control system provided by the embodiment, the control assembly 3 controls the digital pump assembly 2 to act, so that the control on the flow and the oil pressure of an output oil path of the digital pump assembly 2 is realized, and the control assembly 3 controls the execution assembly 1 to act, so that the control on the oil supply pressure of an execution mechanism is realized; and because a single actuating mechanism is supplied with oil by at least one output oil path, hydraulic control on different output oil paths is combined with oil pressure control on the oil inlet end of the actuating mechanism, and hydraulic oil with different pressures can be supplied to different actuating mechanisms.
Compared with the prior art, the hydraulic drive electric control system provided by the embodiment can realize different combinations by controlling the two output oil paths in the use process so as to provide different hydraulic oil with different pressures for different actuating mechanisms; therefore, each actuator can obtain a separate pump source, the function of a pump-actuator is realized, and the digital pump assembly 2 can be arranged to reduce the installation size of the hydraulic drive electric control system. The hydraulic drive electric control system provided by the utility model can well solve the problems of large composite action pressure loss, poor operability, large installation size and increased cost in the prior art, and achieves the effects of strong multi-working condition adaptability, different accessory pressures, strong flow matching capability, good composite action operability, safety, reliability, energy conservation and high efficiency.
In one embodiment, as shown in fig. 1, the actuator assembly 1 includes a rotary actuator 12 and a plurality of mobile actuators 11, and the output oil path includes a rotary oil supply path 226 dedicated to supply oil to the rotary actuator 12 and at least two mobile oil supply paths for supplying oil to the mobile actuators 11; the rotary actuator 12 may be an engine, and the mobile actuator 11 may be a boom, an arm, a bucket, a left walk, a right walk, an assist, a dozer, from left to right in fig. 1; of course, other structures are also possible, and are not described in detail herein.
The movable oil supply oil path is provided with a movable oil supply branch for supplying oil to a single movable actuating mechanism 11, and any movable oil supply branch is provided with a branch electromagnetic valve 13 for controlling the opening and the closing of the branch electromagnetic valve; the rotary oil supply passage 226 is provided with a rotary oil supply solenoid valve 14 for controlling the opening and closing thereof; the branch solenoid valve 13 and the rotary oil supply solenoid valve 14 are both connected with the control assembly 3.
As shown in fig. 1, for the mobile actuator 11 that goes out and dozes, oil is supplied by two output oil paths, and the branch solenoid valves 13 for controlling the opening and closing of any mobile oil supply branch are provided, for example, the oil supply path of the leftmost mobile actuator 11 includes a mobile oil supply branch communicated with one output oil path and another mobile oil supply branch communicated with another output oil path, and the two mobile oil supply branches are provided with the branch solenoid valves 13, and by controlling the opening and closing of the branch solenoid valves 13 in the two mobile oil supply branches, oil supply to the mobile actuator 11 by one mobile oil supply branch can be controlled, oil supply to the mobile actuator 11 by two mobile oil supply branches can be controlled, or oil supply to neither mobile oil supply branch can be controlled. Thereby realizing control of the oil supply pressure of the shift actuator 11.
In fig. 1, only one output oil path is provided for supplying oil to the rotary actuator 12, so that the oil supply of the rotary actuator 12 is not affected by other oil paths, and the use requirement is better met.
Preferably, the control module 3 may include a CAN bus for controlling the rotation speed of the swing actuator 12, so as to control the swing actuator 12 to rotate at different rotation speeds under different operating conditions.
Preferably, the branch solenoid valve 13 and the rotary oil supply solenoid valve 14 are both two-position two-way solenoid valves.
As shown in fig. 1, the digital pump assembly 2 includes a first digital pump 21 and a second digital pump 22, and the first digital pump 21 outputs a first output oil path, which is a first movable oil supply path 213, and the second digital pump 22 outputs two output oil paths, which include a second movable oil supply path 225 and a rotary oil supply path 226.
The flow rate of the first movable oil supply path 213 of the first digital pump 21 is controlled by a plurality of first plungers 211, in fig. 1, six first plungers 211 are arranged in the first digital pump 21, and the first digital pump 21 includes a plurality of first electromagnetic valves 212, the first electromagnetic valves 212 are arranged in one-to-one correspondence with the first plungers 211 to control the number of the first plungers 211 connected to the output oil path of the first digital pump 21, and the first electromagnetic valves 212 are connected to the control assembly 3; in the using process, the control assembly 3 can control the opening and closing of each first electromagnetic valve 212, so that whether the first plunger 211 is connected with the first movable oil supply oil path 213 is realized; in fig. 1, when the first solenoid valve 212 is fully closed, all the first plungers 211 are connected to the first moving oil supply passage 213, and the corresponding first solenoid valves 212 are controlled to be opened, so that the corresponding first plungers 211 are connected to the oil return passage 4 and withdrawn from the first moving oil supply passage 213, thereby controlling the flow rate and the oil pressure of the first moving oil supply passage 213.
The flow rate of the second moving oil supply passage 225 of the second digital pump 22 is controlled by the plurality of second plungers 221, and the flow rate of the revolving oil supply passage 226 is controlled by the plurality of third plungers 222, as shown in fig. 1, the number of the second plungers 221 in fig. 1 is three, and three second electromagnetic valves 223 are correspondingly provided; the number of the third plungers 222 is three, and three third electromagnetic valves 224 are correspondingly arranged; in the using process, all the second electromagnetic valves 223 are controlled to be closed, so that the three second plungers 221 can simultaneously supply oil to the second movable oil supply oil path 225, the corresponding second electromagnetic valves 223 are controlled to be opened, and the corresponding second plungers 221 are connected into the oil return oil path 4 and quit the second movable oil supply oil path 225, so that the flow and the oil pressure of the second movable oil supply oil path 225 are controlled; all the third electromagnetic valves 224 are controlled to be closed, so that the three third plungers 222 can simultaneously supply oil to the rotary oil supply passage 226, and the corresponding third electromagnetic valves 224 are controlled to be opened, so that the corresponding third plungers 222 are connected to the oil return passage 4 and quit from the rotary oil supply passage 226 to supply oil, and therefore the control of the oil supply flow and the oil pressure of the rotary oil supply passage 226 is realized.
It should be noted that the first solenoid valve 212, the second solenoid valve 223, and the third solenoid valve 224 mentioned in this application document may be two-position two-way solenoid valves, and of course, may also be other valve body structures, which are not described herein.
The digital valve component in the application document can be independently connected with a two-position two-way electromagnetic valve at an oil inlet of each actuating mechanism without adopting an integrated form, and is specifically determined according to actual conditions.
The core content of this application document lies in according to a pump actuating mechanism's thinking, forms three different discharge capacity and changeable independent pump of discharge capacity with two digital pumps, with the gyration action separately, form big inertia pressure, the independent unit of flow control, wherein the pump adopts plunger discharge capacity independent control, the valve adopts the entry combination control.
In addition to the above-mentioned liquid-driven electric control system, the present invention also provides an excavator including the liquid-driven electric control system disclosed in the above-mentioned embodiment, and the structure of other parts of the excavator refers to the prior art, and is not described herein again.
The first plunger 211, the second plunger 221, and the third plunger 222, the first electromagnetic valve 212, the second electromagnetic valve 223, and the third electromagnetic valve 224, and the "first", "second", and "third" in the first movable oil supply passage 213 and the second movable oil supply passage 225, which are mentioned in this document, are merely to distinguish the difference in position, and are not sequentially assigned.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. Any combination of all the embodiments provided by the present invention is within the scope of the present invention, and will not be described herein.
The excavator and the hydraulic drive electric control system thereof provided by the utility model are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
Claims (10)
1. A hydraulic drive electric control system is characterized by comprising:
the actuating assembly (1) is provided with a plurality of actuating mechanisms, and the single actuating mechanism is supplied with oil by at least one output oil way;
the digital pump assembly (2) is provided with at least two output oil ways for supplying oil to the execution assembly (1);
the control assembly (3) is used for controlling the actions of the execution assembly (1) and the digital pump assembly (2) so as to realize the oil pressure change of the output oil circuit;
the execution assembly (1) and the digital pump assembly (2) are both connected with the control assembly (3).
2. The system according to claim 1, wherein the actuator assembly (1) comprises a rotary actuator (12) and a plurality of mobile actuators (11), and the output oil path comprises a rotary oil supply path (226) for supplying oil to the rotary actuator (12) and at least two mobile oil supply paths for supplying oil to the mobile actuators (11).
3. The hydraulic drive control system according to claim 2, wherein the control assembly (3) is provided with a CAN bus for controlling the rotation speed of the rotary actuator (12) so as to control the rotary actuator (12) to be at different rotation speeds under different working conditions.
4. The liquid drive electric control system according to claim 2, wherein the mobile oil supply path is provided with a mobile oil supply branch for supplying oil to a single mobile actuating mechanism (11), and any mobile oil supply branch is provided with a branch electromagnetic valve (13) for controlling the opening and closing of the branch electromagnetic valve;
the rotary oil supply oil path (226) is provided with a rotary oil supply electromagnetic valve (14) for controlling the opening and the closing of the rotary oil supply electromagnetic valve;
the branch solenoid valve (13) and the rotary oil supply solenoid valve (14) are connected with the control assembly (3).
5. The hydraulic drive electric control system according to claim 4, wherein the branch solenoid valve (13) and the rotary oil supply solenoid valve (14) are both two-position two-way solenoid valves.
6. The hydraulic drive control system according to claim 1, wherein the digital pump assembly (2) comprises a first digital pump (21) and a second digital pump (22), and the output of the first digital pump (21) has one output oil path and the output of the second digital pump (22) has two output oil paths.
7. The fluid driven electrical control system according to claim 6, wherein the flow rate of the output oil passage of the first digital pump (21) is controlled by a plurality of first plungers (211);
the flow rate of one output oil path of the second digital pump (22) is controlled by a plurality of second plungers (221), and the flow rate of the other output oil path is controlled by a plurality of third plungers (222).
8. The hydraulic drive electric control system according to claim 7, wherein the first digital pump (21) comprises a plurality of first electromagnetic valves (212), the first electromagnetic valves (212) are arranged in one-to-one correspondence with the first plungers (211) to control the number of the first plungers (211) connected to an output oil path of the first digital pump (21);
the first solenoid valve (212) is connected with the control assembly (3).
9. The hydraulically driven electrical control system of claim 7, characterized in that the second digital pump (22) comprises a plurality of second solenoid valves (223) and a plurality of third solenoid valves (224), the second solenoid valves (223) being arranged in one-to-one correspondence with the second plungers (221) to control the number of the second plungers (221) accessing the corresponding output oil paths of the second digital pump (22);
the third electromagnetic valves (224) are arranged in one-to-one correspondence with the third plungers (222) so as to control the number of the third plungers (222) connected to the corresponding output oil paths of the second digital pump (22);
the second solenoid valve (223) and the third solenoid valve (224) are both connected to the control assembly (3).
10. An excavator comprising the fluid driven electrical control system of any one of claims 1 to 9.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202122974705.1U CN216552169U (en) | 2021-11-29 | 2021-11-29 | Excavator and hydraulic drive electric control system thereof |
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| CN202122974705.1U CN216552169U (en) | 2021-11-29 | 2021-11-29 | Excavator and hydraulic drive electric control system thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113969603A (en) * | 2021-11-29 | 2022-01-25 | 山河智能装备股份有限公司 | Excavator and liquid drive electric control system thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113969603A (en) * | 2021-11-29 | 2022-01-25 | 山河智能装备股份有限公司 | Excavator and liquid drive electric control system thereof |
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