CN212248472U - Excavator power response characteristic improving system - Google Patents
Excavator power response characteristic improving system Download PDFInfo
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- CN212248472U CN212248472U CN202021868242.XU CN202021868242U CN212248472U CN 212248472 U CN212248472 U CN 212248472U CN 202021868242 U CN202021868242 U CN 202021868242U CN 212248472 U CN212248472 U CN 212248472U
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Abstract
The embodiment of the application provides an excavator power response characteristic lift system, excavator power response characteristic lift system includes: the hydraulic device is connected with an engine and is driven by the engine to generate hydraulic oil with target pressure; the recovery device is connected with the hydraulic device and is used for recovering the hydraulic oil; the hydraulic drive turbine is connected with the recovery device and is connected with the hydraulic device through a transmission assembly; and the control device is respectively connected with the hydraulic device, the recovery device and the transmission assembly. This application has realized high-efficient recovery and has utilized the hydraulic oil energy, promotes excavator power response characteristic.
Description
Technical Field
The application relates to the technical field of engineering machinery, in particular to a power response characteristic improving system of an excavator.
Background
The hydraulic excavator is a multifunctional machine, is widely applied to mechanical construction of hydraulic engineering, transportation, electric power engineering, mine excavation and the like, and plays an important role in reducing heavy physical labor, ensuring engineering quality, accelerating construction speed and improving labor productivity. In order to effectively improve the working efficiency of the excavator during the operation of the excavator, it is necessary to ensure that the excavator has good power response characteristics. In the prior art, the method of increasing the rotation speed or output power of the diesel engine in advance is usually adopted to improve the power response characteristic of the engine in the loading process, but the turbocharger on the diesel engine inherently has the phenomenon of 'turbo lag', which can cause the air inflow in a cylinder of the diesel engine to be slowly increased, so that the method has very limited improvement effect on the power response characteristic, and also can increase unnecessary energy consumption.
SUMMERY OF THE UTILITY MODEL
An object of the embodiment of the application is to provide an excavator power response characteristic improving system, which is used for realizing efficient recovery and utilization of hydraulic oil energy and improving the excavator power response characteristic.
A first aspect of an embodiment of the present application provides an excavator power response characteristic improving system, including: the hydraulic device is connected with an engine and is driven by the engine to generate hydraulic oil with target pressure; the recovery device is connected with the hydraulic device and is used for recovering the hydraulic oil; the hydraulic drive turbine is connected with the recovery device and is connected with the hydraulic device through a transmission assembly; and the control device is respectively connected with the hydraulic device, the recovery device and the transmission assembly.
In one embodiment, the hydraulic device comprises: the hydraulic pump is connected with the hydraulic drive turbine through the transmission assembly; and the hydraulic valve group is connected with the hydraulic pump through a first hydraulic pipeline and is connected with the recovery device.
In one embodiment, the recycling apparatus includes: the control valve group is connected with the hydraulic device through a second hydraulic pipeline and is connected with the liquid-driven turbine; and the energy storage unit is connected with the control valve group and used for storing and recovering the hydraulic oil.
In one embodiment, the transmission assembly includes: and the speed reducing mechanism is in transmission connection with the liquid drive turbine.
In one embodiment, the speed reducing mechanism includes: the first gear is arranged on a turbine shaft of the liquid-driven turbine; and the second gear is arranged on a connecting shaft of the hydraulic device and the engine, and the second gear is meshed with the first gear.
In one embodiment, the transmission assembly further comprises: and the sliding clutch is arranged between the speed reducing mechanism and the turbine shaft of the liquid-driven turbine and is connected with the control device.
In one embodiment, the diameter of the second gear is larger than the diameter of the first gear.
In one embodiment, the system for improving the dynamic response characteristic of the excavator further comprises: and the oil utilization device is connected with the hydraulic device through a third hydraulic pipeline.
In an embodiment, the oil using device includes a rotation motor, a boom cylinder, an arm cylinder, and a bucket cylinder, and the rotation motor, the boom cylinder, the arm cylinder, and the bucket cylinder are respectively connected to the hydraulic device.
In one embodiment, the system for improving the dynamic response characteristic of the excavator further comprises: and the engine is connected with the hydraulic device and the control device.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.
Fig. 1 is a schematic structural diagram of an excavator power response characteristic improving system according to an embodiment of the present application.
Reference numerals:
100-excavator power response characteristic lifting system, 110-engine, 120-hydraulic device, 121-hydraulic pump, 122-hydraulic valve group, 123-first hydraulic pipeline, 124-connecting shaft, 130-recovery device, 131-second hydraulic pipeline, 132-control valve group, 133-energy storage unit, 140-hydraulic drive turbine, 141-turbine shaft, 150-transmission assembly, 151-first gear, 152-second gear, 153-sliding clutch, 154-speed reduction mechanism, 160-control device, 170-oil using device, 171-slewing motor, 172-boom cylinder, 173-arm cylinder, 174-bucket cylinder, 175-third hydraulic pipeline and 180-operating handle.
Detailed Description
The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.
In the description of the present application, the terms "first," "second," and the like are used for distinguishing between descriptions and do not denote an order of magnitude, nor are they to be construed as indicating or implying relative importance.
In the description of the present application, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are absolutely required to be horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the present application, the terms "upper", "lower", "left", "right", "front", "back", "inner", "outer", and the like refer to orientations or positional relationships that are based on orientations or positional relationships shown in the drawings, or orientations or positional relationships that are conventionally found in the products of the application, and are used for convenience in describing the present application, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present application.
In the description of the present application, the terms "mounted," "disposed," "provided," "connected," and "configured" are to be construed broadly unless expressly stated or limited otherwise. For example, it may be a fixed connection, a removable connection, or a unitary construction; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be internal to two devices, elements or components. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.
Please refer to fig. 1, which is a schematic structural diagram of an excavator power response characteristic improving system 100 according to an embodiment of the present application, including: the hydraulic system comprises an engine 110, a hydraulic device 120, a recovery device 130, a liquid-driven turbine 140, a control device 160 and an oil consumption device 170, wherein the hydraulic device 120 is connected with the engine 110, the hydraulic device 120 is driven by the engine 110 to generate hydraulic oil with target pressure, the recovery device 130 is connected with the hydraulic device 120 and is used for recovering the hydraulic oil, the liquid-driven turbine 140 is connected with the recovery device 130 and is connected with the hydraulic device 120 through a transmission assembly 150, the control device 160 is respectively connected with the hydraulic device 120, the recovery device 130, the transmission assembly 150 and the engine 110, and the oil consumption device 170 is connected with the hydraulic device 120 through a third hydraulic pipeline 175.
In one embodiment, the hydraulic device 120 includes a hydraulic pump 121 and a hydraulic valve assembly 122, the engine 110 is drivingly connected to the hydraulic pump 121 through a connecting shaft 124, the hydraulic turbine 140 is connected to the hydraulic pump 121 through a transmission assembly 150, the hydraulic valve assembly 122 is connected to the hydraulic pump 121 through a first hydraulic line 123, and is connected to the recovery device 130 through a second hydraulic line 131, and is connected to the oil consumption device 170 through a third hydraulic line 175. The engine 110 drives the hydraulic pump 121 to operate at a target gear speed, continuously generates hydraulic oil with a certain pressure, and flows to the hydraulic valve bank 122 through the first hydraulic pipeline 123, an excavator driver can operate the excavator through the operating handle 180, an electric signal is generated by the action of the operating handle 180, and the control device 160 controls the opening or closing of each hydraulic valve in the hydraulic valve bank 122 according to the electric signal or the pressure signal of the pilot hydraulic pipeline, so that the hydraulic oil can flow to the oil consumption device 170 and/or the recovery device 130 according to the operation requirement. In one embodiment, the control device 160 may determine the operation request and the load request to be performed by the excavator according to the position sensor information of the operation handle 180 or the pilot hydraulic line pressure information, and generate a control signal to adjust the swash plate angle of the hydraulic pump 121, thereby adjusting the hydraulic oil flow rate.
In one embodiment, the recycling device 130 includes a control valve set 132 and an energy storage unit 133, the control valve set 132 is connected to the hydraulic device 120 through a second hydraulic line 131 and connected to the hydraulic turbine 140, and the energy storage unit 133 is connected to the control valve set 132 for storing recycled hydraulic oil. In one embodiment, the control valve set 132 returns hydraulic oil with a suitable pressure to the energy storage unit 133 according to a control signal of the control device 160. When power assistance needs to be provided, the control device 160 controls the control valve set 132 to deliver hydraulic oil with pressure in the energy storage unit 133 to the hydraulic turbine 140, so as to drive the hydraulic turbine 140 to rotate, thereby converting hydraulic energy of the hydraulic oil into rotational kinetic energy to directly drive the hydraulic pump 121 through the transmission assembly 150.
In one embodiment, oil consumption device 170 includes a swing motor 171, a boom cylinder 172, an arm cylinder 173, and a bucket cylinder 174, and swing motor 171, boom cylinder 172, arm cylinder 173, and bucket cylinder 174 are connected to hydraulic valve group 122 of hydraulic device 120, respectively. In one embodiment, hydraulic oil of a certain pressure continuously flows from the hydraulic pump 121 to the hydraulic valve set 122 through the first hydraulic line 123, and flows into the swing motor 171, the boom cylinder 172, the arm cylinder 173, and the bucket cylinder 174 through different channels of the third hydraulic line 175, and hydraulic oil also flows back to the hydraulic valve set 122 from the swing motor 171, the boom cylinder 172, the arm cylinder 173, and the bucket cylinder 174, and then flows into the control valve set 132, and the control valve set 132 returns hydraulic oil of a proper pressure to the energy storage unit 133 according to a control signal of the control device 160.
In an embodiment, for a hydraulic excavator adopting a boom potential energy recovery function, hydraulic oil flowing out of the boom cylinder 172 flows into the arm cylinder 173 and/or the bucket cylinder 174, resulting in a reduction in energy of the hydraulic oil recoverable at the boom cylinder 172, and in order not to affect the effect of the lift power response characteristic, the control valve group 132 may directly send high-pressure hydraulic oil generated by the hydraulic pump 121 to the energy storage unit 133 through the second hydraulic line 131 in addition to recovering hydraulic oil flowing back from the swing motor 171, the arm cylinder 173, and the bucket cylinder 174.
In one embodiment, when the excavator is operating under a light load, for example, the excavator is in a flat ground condition, the engine 110 is in a light load state, which deviates from the optimal economic zone for the operation of the engine 110, and reduces the operation efficiency. The control device 160 can increase the hydraulic oil displacement of the hydraulic pump 121, so as to increase the load of the engine 110, so that the engine 110 can be operated close to or in an optimal economic area, thereby improving the operation efficiency of the engine 110, saving oil consumption, and the extra hydraulic oil displacement generated by the hydraulic pump 121 can be recycled to the energy storage unit 133 through the control valve set 132, and then provided to the hydraulic turbine 140 to drive the hydraulic pump 121 when the power response characteristic needs to be improved subsequently.
In one embodiment, the transmission assembly 150 includes a speed reduction mechanism 154 and a slip clutch 153, wherein the speed reduction mechanism 154 includes a first gear 151 and a second gear 152, the first gear 151 is disposed on the turbine shaft 141 of the fluid driven turbine 140, the second gear is disposed on the connecting shaft 124 of the hydraulic device 120 and the engine 110, the second gear 152 is engaged with the first gear 151, and the diameter of the second gear 152 is greater than that of the first gear 151, thereby achieving the matching of the rotation speed between the high-speed rotation of the fluid driven turbine 140 and the low-speed rotation of the hydraulic pump 121 of the engine 110. The sliding clutch 153 is arranged between the first gear 151 and the turbine shaft 141 of the hydraulic turbine 140, and is connected with a control device 160, and the control device 160 is used for controlling the separation and engagement states of the sliding clutch 153. In one embodiment, when the boosting force is not required to be provided by the hydraulic turbine 140, the control device 160 sends a signal to the control valve set 132 to reduce or close the hydraulic oil supplied to the hydraulic turbine 140, and the sliding clutch 153 separates the turbine shaft 141 from the first gear 151, thereby preventing the hydraulic turbine 140 from over-speed or idling and causing a reduction in life.
In an embodiment, the control device 160 transmits the hydraulic oil in the energy storage unit 133 to the hydraulic turbine 140 through the control valve set 132 according to a demand that the engine 110 needs to provide power quickly, so as to drive the hydraulic turbine 140 to rotate at a high speed, and convert the hydraulic energy into kinetic energy for rotating the turbine shaft 141. The first gear 151 mounted on the turbine shaft 141 and the second gear 152 mounted on the connecting shaft 124 are engaged to rotate, and the kinetic energy of the turbine shaft 141 is directly transmitted to the connecting shaft 124 to drive the hydraulic pump 121 to rotate. In one embodiment, the second gear 152 may also be mounted on the flywheel of the engine 110. Because the hydraulic drive turbine 140 directly transmits energy to the hydraulic pump 121, power transmission is fast, transmission efficiency is high, the matching degree of the output power of the hydraulic pump 121 and the external load requirement can be improved, and the power response characteristic of the excavator is remarkably improved.
In one embodiment, when the external load suddenly increases, the engine 110 is required to rapidly output power to the hydraulic pump 121, and the rotation speed of the engine 110 is significantly reduced under the sudden load increase due to the "turbo lag" effect. The control device 160 may obtain the external load sudden increase information in advance through an electric signal of the operation handle 180 or a pilot hydraulic line pressure signal, and flow the hydraulic oil in the energy storage unit 133 to the hydraulic turbine 140 through the control valve set 132, so as to drive the hydraulic turbine 140 to rotate at a high speed, thereby generating rotational kinetic energy. The control device 160 also controls the slip clutch 153 to engage, so that the rotational kinetic energy of the turbine shaft 141 is transmitted to the second gear 152 through the first gear 151, the hydraulic pump 121 is driven rapidly, the requirement on the output power of the engine 110 is partially reduced or completely counteracted, the assistance to the engine 110 is realized, and the requirement of sudden increase of external load is met. In providing the boosting force to the engine 110, the control device 160 can instantaneously adjust the flow rate of the hydraulic oil entering the hydraulic turbine 140 through the control valve set 132 according to the change of the external load, so that the magnitude of the boosting force supplied to the engine 110 can be adjusted. The hydraulic pump 121 is directly driven by the liquid-driven turbine 140, so that the falling speed amplitude of the engine 110 can be effectively reduced, the engine 110 can work stably, and the fuel consumption is reduced.
In one embodiment, when the external load suddenly decreases, the power absorbed by the hydraulic pump 121 is instantaneously reduced, and the rotational speeds of the engine 110 and the hydraulic pump 121 are instantaneously increased to far exceed the set speed of the gear due to the delay in the power output adjustment of the engine 110. The control device 160 may obtain sudden drop information of the external load in advance, gradually reduce the swash plate swing angle of the hydraulic pump 121 to reduce the hydraulic oil displacement of the hydraulic pump 121, and simultaneously, by controlling the hydraulic valve group 122 in time, the hydraulic oil originally supplied to the rotary motor 171, the boom cylinder 172, the arm cylinder 173, and the bucket cylinder 174 is supplied to the energy storage unit 133 through the control valve group 132 to store the hydraulic energy, so that the output power of the hydraulic pump 121 is changed from sudden drop to slow drop, thereby adapting to the characteristic that the output power of the engine 110 is slowly adjusted, reducing the rising amplitude of the rotating speed, being beneficial to reducing the noise of the engine 110 and the hydraulic pump 121, and reducing the increase of oil consumption caused by overspeed.
In an embodiment, the pressure values of the hydraulic oil inside the energy storage unit 133 may be set to three gears according to the magnitude sequence. The value a1 represents the maximum working value of the energy storage unit 133, and when the value is reached, the high-pressure hydraulic oil is not recovered, so that the energy storage unit 133 is protected from being damaged. The value a2 represents the minimum value of the energy storage unit 133 operation, and below this value it means that the operation state of the following fluid driven turbine 140 and thus the driving of the hydraulic pump 121 will be affected. A1 and a2 may be set as needed, and if higher power response characteristics are required, a1 and a2 are set closer.
In one embodiment, when the internal pressure of the energy storage unit 133 is between a1 and a2 and the hydraulic pump 121 or the engine 110 is in the non-efficient operation region, the control device 160 adjusts the operation point of the hydraulic pump 121 or the engine 110 to be close to the efficient region, because the hydraulic pump 121 and the engine 110 are both in the high-load operation region, when the operation point of the hydraulic pump 121 or the engine 110 is adjusted to be in the efficient region, the hydraulic oil displacement of the hydraulic pump 121 is also increased, and the hydraulic valve connected to the second hydraulic line 131 inside the hydraulic valve bank 122 is opened, so that the additionally generated high-pressure hydraulic oil is delivered to the energy storage unit 133 through the second hydraulic line 131.
In an embodiment, when the internal pressure of the energy storage unit 133 is between a1 and a2 and the hydraulic pump 121 and the engine 110 are already operating in their respective high-efficiency areas, the pressure of the hydraulic oil at the outlet of the oil consuming device 170 is higher, and more hydraulic energy can be recovered, so that only the hydraulic oil at the outlet of the oil consuming device 170 is recovered, and the operating condition of the hydraulic pump 121 or the engine 110 is not adjusted.
In one embodiment, when the internal pressure of the energy storage unit 133 is lower than a2, no matter whether the hydraulic pump 121 or the engine 110 is in high efficiency, the control device 160 controls the hydraulic pump 121 to actively increase the displacement of the high-pressure hydraulic oil, and the high-pressure hydraulic oil is supplied to the energy storage unit 133 through the second hydraulic line 131 and the control valve set 132 to increase the internal hydraulic energy thereof.
The above are merely preferred embodiments of the present application and are not intended to limit the present application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. An excavator power response characteristic improving system, comprising:
the hydraulic device is connected with an engine and is driven by the engine to generate hydraulic oil with target pressure;
the recovery device is connected with the hydraulic device and is used for recovering the hydraulic oil;
the hydraulic drive turbine is connected with the recovery device and is connected with the hydraulic device through a transmission assembly;
and the control device is respectively connected with the hydraulic device, the recovery device and the transmission assembly.
2. The excavator power response characteristic elevation system of claim 1 wherein the hydraulic means comprises:
the hydraulic pump is connected with the hydraulic drive turbine through the transmission assembly;
and the hydraulic valve group is connected with the hydraulic pump through a first hydraulic pipeline and is connected with the recovery device.
3. The excavator power response characteristic elevation system of claim 1, wherein the recovery device comprises:
the control valve group is connected with the hydraulic device through a second hydraulic pipeline and is connected with the liquid-driven turbine;
and the energy storage unit is connected with the control valve group and used for storing and recovering the hydraulic oil.
4. The excavator power response characteristic elevation system of claim 1 wherein the drive assembly comprises:
and the speed reducing mechanism is in transmission connection with the liquid drive turbine.
5. The excavator power response characteristic elevation system of claim 4 wherein the speed reduction mechanism comprises:
the first gear is arranged on a turbine shaft of the liquid-driven turbine;
and the second gear is arranged on a connecting shaft of the hydraulic device and the engine, and the second gear is meshed with the first gear.
6. The excavator power response characteristic elevation system of claim 4 wherein the drive assembly further comprises:
and the sliding clutch is arranged between the speed reducing mechanism and the turbine shaft of the liquid-driven turbine and is connected with the control device.
7. The excavator power response characteristic elevation system of claim 5 wherein the diameter of the second gear is greater than the diameter of the first gear.
8. The excavator power response characteristic elevation system of claim 1, further comprising:
and the oil utilization device is connected with the hydraulic device through a third hydraulic pipeline.
9. The excavator power response characteristic elevation system of claim 8 wherein the oil consuming device includes a swing motor, a boom cylinder, an arm cylinder and a bucket cylinder, the swing motor, the boom cylinder, the arm cylinder and the bucket cylinder being connected to the hydraulic device, respectively.
10. The excavator power response characteristic elevation system of claim 1, further comprising:
and the engine is connected with the hydraulic device and the control device.
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| CN202021868242.XU CN212248472U (en) | 2020-08-31 | 2020-08-31 | Excavator power response characteristic improving system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111877453A (en) * | 2020-08-31 | 2020-11-03 | 上海华兴数字科技有限公司 | Excavator power response characteristic improving system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111877453A (en) * | 2020-08-31 | 2020-11-03 | 上海华兴数字科技有限公司 | Excavator power response characteristic improving system |
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