CN114076126A - Rotary driving system and engineering machinery - Google Patents
Rotary driving system and engineering machinery Download PDFInfo
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- CN114076126A CN114076126A CN202111376661.0A CN202111376661A CN114076126A CN 114076126 A CN114076126 A CN 114076126A CN 202111376661 A CN202111376661 A CN 202111376661A CN 114076126 A CN114076126 A CN 114076126A
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- 239000003921 oil Substances 0.000 claims abstract description 48
- 239000010729 system oil Substances 0.000 claims abstract description 26
- 230000001105 regulatory effect Effects 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 abstract description 5
- 238000010276 construction Methods 0.000 description 9
- 230000007246 mechanism Effects 0.000 description 8
- 230000003139 buffering effect Effects 0.000 description 7
- 238000006073 displacement reaction Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 239000010720 hydraulic oil Substances 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000003801 milling Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000009194 climbing Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Operation Control Of Excavators (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a rotary driving system, which comprises a system oil source, a main motor, an auxiliary motor and a gear shifting valve, wherein the system oil source is connected with a first main working port and a second main working port of the main motor, a first auxiliary working port of the auxiliary motor is communicated with the first main working port, a second auxiliary working port of the auxiliary motor is communicated with a first gear shifting working port of the gear shifting valve, a second gear shifting working port of the gear shifting valve is communicated with the second main working port, a third gear shifting working port of the gear shifting valve is simultaneously communicated with the first auxiliary working port, the first gear shifting working port is communicated with the second gear shifting working port in a low-speed gear position, the second auxiliary working port is communicated with the second main working port, and the first gear shifting working port is communicated with the third gear shifting working port in a high-speed gear position, so that the second auxiliary working port is communicated with the first auxiliary working port. The oil circuit is simple and reliable, reduces system cost, has reduced system heating and power loss, avoids assisting the motor and inhales empty, can be applied to open system and closed system, promotes system's suitability. The invention also discloses engineering machinery comprising the rotary driving system.
Description
Technical Field
The invention relates to the field of hydraulic systems, in particular to a rotary driving system. In addition, the invention also relates to a construction machine comprising the slewing drive system.
Background
In a hydraulic swing driving system of an engineering machine, motors are generally adopted for driving, for example, an all-terrain crane and a large excavator are driven to swing by adopting double quantitative motors in parallel, and a boom tower crane hydraulic swing system is driven by adopting a plurality of quantitative motors in parallel. For engineering machinery with multi-working-condition application, the rotary driving system is required to be switched between a large torque state and a high rotating speed state. For example, the shovel mill requires fast rotation in the shovel loading condition to improve the working efficiency, and the milling and digging condition can provide large torque to offset the milling, digging and cutting force.
In the prior art, the displacement change of a variable displacement plunger motor is mainly adopted to give consideration to two industrial controls of large torque and high speed. For example, the excavator walking system adopts a two-gear variable motor, namely, the two-gear control of low-speed and high-speed walking is obtained by switching the large displacement and the small displacement of the variable motor, so as to consider both the walking propulsion and the transition efficiency of equipment. When the walking motor is in large displacement, the driving force is large, the walking speed is low, and the walking motor is suitable for working conditions needing large walking driving force, such as climbing. When the walking motor is in small displacement, the walking speed is high, the driving force is small, and the walking motor is suitable for the working conditions needing quick movement, such as equipment transition and the like. However, the above method has a complicated structure, requires a plurality of elements, has no oil compensation measure, increases pressure loss, and generates redundant power loss.
Therefore, how to provide a swing driving system with simple structure and less power loss is a technical problem that needs to be solved by those skilled in the art.
Disclosure of Invention
The invention aims to provide a rotary driving system, which controls whether an auxiliary motor is connected to a main oil circuit or not through a gear shifting valve, realizes gear switching, is simple and reliable in oil circuit, and reduces cost, system heating and power loss. Another object of the present invention is to provide a working machine comprising the above swing drive system.
In order to solve the above technical problems, the present invention provides a swing drive system, comprising a system oil source, a main motor, an auxiliary motor and a shift valve, the system oil source is connected with the first main working port and the second main working port of the main motor, the first auxiliary working port of the auxiliary motor is communicated with the first main working port, the second auxiliary working port of the auxiliary motor is communicated with the first shifting working port of the shifting valve, the second shifting working port of the shifting valve is communicated with the second main working port, and a third gear shifting working port of the gear shifting valve is simultaneously communicated with the first auxiliary working port, and the first gear shifting working port is communicated with the second gear shifting working port during a low-speed gear position, so that the second auxiliary working port is communicated with the second main working port, and the first gear shifting working port is communicated with the third gear shifting working port during a high-speed gear position, so that the second auxiliary working port is communicated with the first auxiliary working port.
Preferably, the system further comprises a reversing valve, an oil supply port and an oil return port of the reversing valve are connected with the system oil source, and two working oil ports of the reversing valve are respectively communicated with the first main working port and the second main working port.
Preferably, the hydraulic control system further comprises two buffer overflow valves arranged between the reversing valve and the main motor, oil inlets and oil outlets of the buffer overflow valves are respectively connected with two working oil ports of the reversing valve, and the directions of the two buffer overflow valves are opposite.
Preferably, the gear shifting valve is a two-position three-way electromagnetic directional valve, when the two-position three-way electromagnetic directional valve is located at a first working position, the first gear shifting working port is communicated with the second gear shifting working port, and when the two-position three-way electromagnetic directional valve is located at a second working position, the first gear shifting working port is communicated with the third gear shifting working port.
Preferably, the reversing valve is a three-position four-way electromagnetic proportional regulating valve.
Preferably, a plurality of said secondary motors are included in parallel with said main motor, each said secondary motor being connected to one said shift valve.
Preferably, the system oil source is a closed oil source.
Preferably, the main motor and the auxiliary motor are quantitative motors, and the main motor and the auxiliary motor are respectively connected with a safety valve group in parallel.
Preferably, a fixing seat is arranged on the auxiliary motor, and the gear shifting valve is integrally installed on the fixing seat.
The invention provides a construction machine comprising a slewing drive system as defined in any one of the preceding claims.
The invention provides a rotary driving system which comprises a system oil source, a main motor, an auxiliary motor and a gear shifting valve, wherein the system oil source is connected with a first main working port and a second main working port of the main motor, a first auxiliary working port of the auxiliary motor is communicated with the first main working port, a second auxiliary working port of the auxiliary motor is communicated with a first gear shifting working port of the gear shifting valve, a second gear shifting working port of the gear shifting valve is communicated with the second main working port, a third gear shifting working port of the gear shifting valve is simultaneously communicated with the first auxiliary working port, the first gear shifting working port is communicated with the second gear shifting working port in a low-speed gear position, the second auxiliary working port is communicated with the second main working port, the first gear shifting working port is communicated with the third gear shifting working port in a high-speed gear position, and the second auxiliary working port is communicated with the first auxiliary working port.
In the working process, hydraulic oil provided by a system oil source enters and exits from a first main working port and a second main working port of a main motor to drive the main motor to normally work and realize the forward rotation, the reverse rotation and the stop of the main motor so as to realize the forward rotation and the reverse rotation and the stop of a slewing mechanism, when a shift valve 5 is switched to a low-speed gear position, a first shift working port of the shift valve is communicated with a second shift working port, a second auxiliary working port of an auxiliary motor is communicated with a second main working port of the main motor, a first auxiliary working port of the auxiliary motor is always communicated with a first main working port of the main motor, the main motor and the auxiliary motor are connected into a system in parallel, the main motor and the auxiliary motor drive the slewing mechanism to act together, the working flow of the system is simultaneously supplied to the main motor and the auxiliary motor, the speeds of the main motor and the auxiliary motor are lower, and the slewing drive system works in a low-speed high-torque mode.
When the gear shifting valve 5 is switched to a high-speed gear, the first gear shifting working port of the gear shifting valve is communicated with the third gear shifting working port, so that the second auxiliary working port of the auxiliary motor is communicated with the first auxiliary working port of the auxiliary motor, and the auxiliary motor is in a floating state. The main motor is only used for driving the slewing mechanism to act, the system working flow is only supplied to the main motor, and the slewing driving system works in a high-speed small-torque mode. During the rotation process of the auxiliary motor along with the rotation mechanism, oil drainage liquid of the auxiliary motor is supplemented by a system oil source, and the auxiliary motor is prevented from being sucked empty.
Whether the auxiliary motor is connected to the main oil circuit or not is controlled through the gear shifting valve, gear control of a rotary driving system is achieved, the oil circuit is simple and reliable, system cost is reduced, the problem that pressure loss caused by a series connection system is accumulated when a high-speed gear works is avoided, system heating and power loss are reduced, oil is supplemented to the auxiliary motor in a floating state through the working oil circuit, air suction of the auxiliary motor is avoided, damage of the auxiliary motor is prevented, the auxiliary motor can be applied to an open system and a closed system, and system applicability is improved.
The invention also provides a construction machine comprising the slewing drive system, and the construction machine has the technical effects due to the technical effects of the slewing drive system, so that the construction machine is not described in detail.
Drawings
FIG. 1 is a hydraulic schematic of one embodiment of a swing drive system provided by the present invention;
fig. 2 is a hydraulic schematic diagram of another embodiment of a swing drive system provided by the present invention.
Detailed Description
The core of the invention is to provide a rotary driving system, which controls whether an auxiliary motor is connected with a main oil circuit or not through a gear shifting valve, realizes gear switching, has simple and reliable oil circuit, and reduces cost, system heating and power loss. Another core of the invention is to provide a construction machine comprising the slewing drive system.
In order that those skilled in the art will better understand the disclosure, the invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Referring to fig. 1, fig. 1 is a hydraulic schematic diagram of a swing driving system according to an embodiment of the present invention.
The embodiment of the invention provides a slewing drive system which comprises a system oil source 6, a main motor 1, an auxiliary motor 2 and a gear shifting valve 3, wherein the main motor 1 is provided with a first main working port A1 and a second main working port A2, the auxiliary motor 2 is provided with a first auxiliary working port B1 and a second auxiliary working port B2, and the gear shifting valve 3 is provided with a first gear shifting working port C1, a second gear shifting working port C2 and a third gear shifting working port C3.
The oil supply and the oil return of the system oil source 6 are respectively connected with the first main working port a1 and the second main working port a2 of the main motor 1, the first auxiliary working port B1 of the auxiliary motor 2 is communicated with the first main working port a1 of the main motor 1, namely, the first auxiliary working port B1 of the auxiliary motor 2 is also simultaneously connected with the system oil source 6, the second auxiliary working port B2 of the auxiliary motor 2 is communicated with the first shifting working port C1 of the shift valve 3, the second shifting working port C2 of the shift valve 3 is communicated with the second main working port a2 of the main motor 1, namely, the second shifting working port C2 of the shift valve 3 is also simultaneously connected with the system oil source 6, and the third shifting working port C3 of the shift valve 3 is simultaneously communicated with the first auxiliary working port B1 of the auxiliary motor 2.
In a low gear, the first shift working port C1 is communicated with the second shift working port C2, so that the second auxiliary working port B2 is communicated with the second main working port a2, i.e., the second auxiliary working port B2 is simultaneously connected with the system oil source 6. In the high gear, the first shift operating port C1 is communicated with the third shift operating port C3, and the second auxiliary operating port B2 is communicated with the first auxiliary operating port B1.
In the working process, the hydraulic oil provided by the system oil source 6 enters and exits the first main working port a1 and the second main working port a2 of the main motor 1 to drive the main motor 1 to normally work, so that the main motor 1 is rotated forwards, backwards and stopped, and the rotation mechanism is rotated forwards, backwards and stopped. When the shift valve 5 is switched to the low-speed gear position, the first shift working port C1 of the shift valve 5 is communicated with the second shift working port C2, the second auxiliary working port B2 of the auxiliary motor 2 is communicated with the second main working port a1 of the main motor 1, the first auxiliary working port B1 of the auxiliary motor 2 is always communicated with the first main working port a1 of the main motor 1, the main motor 1 and the auxiliary motor 2 are connected in parallel to a system, hydraulic oil supplied by the system oil source 6 normally enters the first auxiliary working port B1 of the auxiliary motor 2, and hydraulic oil supplied by the system oil source 6 enters the second auxiliary working port B2 of the auxiliary motor 2 through the shift valve 5. The main motor 1 and the auxiliary motor 2 drive the slewing mechanism to act together, the working flow of the system is simultaneously supplied to the main motor 1 and the auxiliary motor 2, the speed of the main motor 1 and the auxiliary motor 2 is low, and the slewing driving system works in a low-speed large-torque mode.
When the shift valve 5 is shifted to the high gear, the first shift gate C1 of the shift valve 5 communicates with the third shift gate C3, the second auxiliary gate B2 of the auxiliary motor 2 communicates with the first auxiliary gate B1 thereof, and the auxiliary motor 2 is in a floating state. The main motor 1 is only used for driving the slewing mechanism to act, the system working flow is only supplied to the main motor 1, and the slewing driving system works in a high-speed small-torque mode. During the rotation process of the auxiliary motor 2 along with the rotation mechanism, two working ports of the auxiliary motor 2 are communicated through the gear shifting valve 5 and are simultaneously connected to the system oil source 6, oil drainage liquid of the auxiliary motor 2 is supplemented by the system oil source 6, and the auxiliary motor 2 is prevented from being sucked empty.
Whether the auxiliary motor 2 is connected to the main oil circuit or not is controlled through the gear shifting valve 5, gear control of a rotary driving system is achieved, the oil circuit is simple and reliable, system cost is reduced, the problem that pressure loss accumulation caused by a series connection system is avoided when a high-speed gear works, system heating and power loss are reduced, oil is supplemented to the auxiliary motor 2 in a floating state through the working oil circuit, air suction of the auxiliary motor 2 is avoided, damage to the auxiliary motor 2 is prevented, the auxiliary motor can be applied to an open system and a closed system, and system applicability is improved.
Specifically, in order to realize reversing, a reversing valve 4 can be further arranged, an oil supply port P and an oil return port T of the reversing valve 4 are connected with a system oil source 6, and two working oil ports A and B of the reversing valve 4 are respectively communicated with a first main working port A1 and a second main working port A2. The normal rotation, reverse rotation and stop of the main motor 1 and the auxiliary motor 2 are realized by switching the working positions of the reversing valve 4.
Further, the shift valve 3 is specifically a two-position three-way electromagnetic directional valve 4, when the two-position three-way electromagnetic directional valve 4 is located at the first working position, the first shift working port C1 is communicated with the second shift working port C2, when the two-position three-way electromagnetic directional valve 4 is located at the second working position, the first shift working port C1 is communicated with the third shift working port C3, and the directional valve 4 is specifically a three-position four-way electromagnetic proportional control valve, and the type of the valve can be adjusted according to the situation, and the two-position three-way electromagnetic directional valve is within the protection range of the present invention.
In order to improve the system safety, two buffering overflow valves 5 can be further arranged, the two buffering overflow valves 5 are arranged between the reversing valve 4 and the main motor 1, an oil inlet of the first buffering overflow valve 5 is communicated with a working oil port A of the reversing valve 4, an oil outlet of the first buffering overflow valve 5 is communicated with a working oil port B of the reversing valve 4, an oil inlet of the second buffering overflow valve 5 is communicated with a working oil port B of the reversing valve 4, an oil outlet of the second buffering overflow valve 5 is communicated with the working oil port A of the reversing valve 4, and the directions of the two buffering overflow valves 5 are opposite. The hydraulic control system is used for limiting the highest working pressure of two working oil paths in the system and absorbing pressure impact on the oil paths, and high-pressure oil input by the reversing valve 4 enters any oil path and can be matched with a buffer overflow valve 5.
In the swing drive system according to the embodiment of the present invention, a plurality of sub motors 2 may be provided in parallel with the main motor 1 according to circumstances, each sub motor 2 is connected to one shift valve 3, the connection is performed in such a manner that the sub motors 2 do not interfere with each other, and the shift valves 3 may be controlled synchronously or individually.
The system can be applied to an open system or a closed system, please refer to fig. 2, and fig. 2 is a hydraulic schematic diagram of another embodiment of the swing driving system provided by the present invention.
The system oil source 6 is specifically a closed oil source, the main motor 1 and the auxiliary motor 2 are quantitative motors, the main motor 1 and the auxiliary motor 2 are respectively connected with a safety valve group in parallel, the safety valve group and the motors can be regarded as a whole, and the connection mode and the working mode are as described above.
On the basis of the swing driving system provided by each of the above embodiments, the auxiliary motor 2 is provided with a fixed seat, and the shift valve 3 is integrally mounted on the fixed seat. The pressure loss generated by a B2-C1-C3-B1 circuit is reduced, and the pressure loss generated by a B2-C1-C3-B1 circuit is smaller than that of a series system because the working flow of a high-speed gear system does not flow through A-B1 and B-C2 pipelines.
In addition to the above-mentioned swing driving system, a construction machine including the above-mentioned swing driving system is provided in the embodiments of the present invention, and the structure of other parts of the construction machine refers to the prior art and is not described herein again.
Specifically, the engineering machine may be an all-terrain crane, a large excavator, a boom tower crane, a shovel mill, or the like.
The slewing drive system and the construction machine provided by the invention 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 swing drive system comprising a system oil source (6), a main motor (1), an auxiliary motor (2) and a shift valve (3), said system oil source (6) connecting a first main working port (A1) and a second main working port (A2) of said main motor (1), a first auxiliary working port (B1) of said auxiliary motor (2) communicating with said first main working port (A1), a second auxiliary working port (B2) of said auxiliary motor (2) communicating with a first shift working port (C1) of said shift valve (3), a second shift working port (C2) of said shift valve (3) communicating with said second main working port (A2), a third shift working port (C3) of said shift valve (3) communicating with said first auxiliary working port (B1) simultaneously, said first shift working port (C1) communicating with said second shift working port (C2) at low gear, and enabling the second auxiliary working port (B2) to be communicated with the second main working port (A2), enabling the first gear shifting working port (C1) to be communicated with the third gear shifting working port (C3) during high-speed gear, and enabling the second auxiliary working port (B2) to be communicated with the first auxiliary working port (B1).
2. The swing drive system according to claim 1, further comprising a direction valve (4), wherein an oil supply port and an oil return port of the direction valve (4) are connected to the system oil source (6), and two working oil ports of the direction valve (4) are respectively communicated with the first main working port (a1) and the second main working port (a 2).
3. The swing drive system according to claim 2, further comprising two buffer overflow valves (5) disposed between the reversing valve (4) and the main motor (1), wherein an oil inlet and an oil outlet of the buffer overflow valves (5) are respectively connected to two working oil ports of the reversing valve (4), and directions of the two buffer overflow valves (5) are opposite.
4. A swing drive system according to claim 3, wherein the gear shift valve (3) is embodied as a two-position three-way electromagnetic directional valve (4), the first shift working port (C1) communicating with the second shift working port (C2) when the two-position three-way electromagnetic directional valve (4) is in the first operating position, and the first shift working port (C1) communicating with the third shift working port (C3) when the two-position three-way electromagnetic directional valve (4) is in the second operating position.
5. A swing drive system according to claim 4, wherein the reversing valve (4) is embodied as a three-position four-way electromagnetic proportional regulating valve.
6. A swing drive system according to claim 1, comprising a plurality of said secondary motors (2) connected in parallel with said main motor (1), each said secondary motor (2) being connected to one said shift valve (3).
7. A swing drive system according to claim 1, wherein the system oil source (6) is embodied as a closed oil source.
8. A swing drive system according to claim 7, wherein the main motor (1) and the auxiliary motor (2) are quantitative motors, the main motor (1) and the auxiliary motor (2) each being connected in parallel with a safety valve pack.
9. A swing drive system according to any one of claims 1-8, wherein the auxiliary motor (2) is provided with a fixing seat on which the gear shift valve (3) is integrally mounted.
10. A working machine comprising a swing drive system according to any of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111376661.0A CN114076126A (en) | 2021-11-19 | 2021-11-19 | Rotary driving system and engineering machinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111376661.0A CN114076126A (en) | 2021-11-19 | 2021-11-19 | Rotary driving system and engineering machinery |
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| Publication Number | Publication Date |
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| CN114076126A true CN114076126A (en) | 2022-02-22 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111376661.0A Withdrawn CN114076126A (en) | 2021-11-19 | 2021-11-19 | Rotary driving system and engineering machinery |
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| Country | Link |
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| CN (1) | CN114076126A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1086789A (en) * | 1992-11-08 | 1994-05-18 | 铁道部兰州机车工厂 | Hydraulic driving system for single hook double hoisting crane |
| CN102490596A (en) * | 2011-11-22 | 2012-06-13 | 徐工集团工程机械股份有限公司科技分公司 | Electric hydraulic control and hydraulic drive speed change system for road roller with double steel wheels |
| CN102717706A (en) * | 2012-05-26 | 2012-10-10 | 三一重型装备有限公司 | Engineering machine and travelling driving system thereof |
| CN103062141A (en) * | 2012-12-21 | 2013-04-24 | 三一重型装备有限公司 | Track traveling mechanism, hydraulic system thereof and engineering machinery |
-
2021
- 2021-11-19 CN CN202111376661.0A patent/CN114076126A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1086789A (en) * | 1992-11-08 | 1994-05-18 | 铁道部兰州机车工厂 | Hydraulic driving system for single hook double hoisting crane |
| CN102490596A (en) * | 2011-11-22 | 2012-06-13 | 徐工集团工程机械股份有限公司科技分公司 | Electric hydraulic control and hydraulic drive speed change system for road roller with double steel wheels |
| CN102717706A (en) * | 2012-05-26 | 2012-10-10 | 三一重型装备有限公司 | Engineering machine and travelling driving system thereof |
| CN103062141A (en) * | 2012-12-21 | 2013-04-24 | 三一重型装备有限公司 | Track traveling mechanism, hydraulic system thereof and engineering machinery |
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Application publication date: 20220222 |