阅读说明：本技术 一种新型下车液压系统及工程机械 (Novel hydraulic system and engineering machinery get off ) 是由 任丁红 陆晓兵 王坤 于 2020-05-07 设计创作，主要内容包括：本发明公开了一种新型下车液压系统及工程机械,涉及工程机械技术领域。该新型下车液压系统包括选择阀、换向阀、第一溢流阀、回油管路及第一支腿油缸,选择阀分别与换向阀、第一溢流阀、回油管路及第一支腿油缸的大腔接口连接,回油管路还分别与换向阀及第一溢流阀连接,第一支腿油缸的小腔接口与换向阀连接；当选择阀处于第一工作位时,换向阀、第一溢流阀、回油管路及第一支腿油缸的大腔接口相互之间不连通；当选择阀处于第二工作位时,换向阀、第一溢流阀及第一支腿油缸的大腔接口在选择阀的内部连通。本发明提供的新型下车液压系统能够对第一支腿油缸进行承压限制,防止第一支腿油缸因承压过大而变形损坏。(The invention discloses a novel get-off hydraulic system and engineering machinery, and relates to the technical field of engineering machinery. The novel hydraulic system for the lower vehicle comprises a selector valve, a reversing valve, a first overflow valve, an oil return pipeline and a first leg oil cylinder, wherein the selector valve is respectively connected with the reversing valve, the first overflow valve, the oil return pipeline and a large cavity interface of the first leg oil cylinder; when the selector valve is in the first working position, the reversing valve, the first overflow valve, the oil return pipeline and the large cavity interface of the first leg oil cylinder are not communicated with each other; when the selector valve is in the second working position, the reversing valve, the first overflow valve and the large cavity interface of the first leg oil cylinder are communicated in the selector valve. The novel hydraulic system for the get-off vehicle can limit the bearing of the first leg oil cylinder and prevent the first leg oil cylinder from being deformed and damaged due to overlarge bearing.)

1. The novel hydraulic system for the lower vehicle is characterized by comprising a selector valve, a reversing valve, a first overflow valve, an oil return pipeline and a first leg oil cylinder, wherein the selector valve is respectively connected with the reversing valve, the first overflow valve, the oil return pipeline and a large cavity interface of the first leg oil cylinder;

when the selector valve is in a first working position, the reversing valve, the first overflow valve, the oil return pipeline and a large cavity interface of the first support oil cylinder are not communicated with each other in the selector valve;

when the selector valve is in a second working position, the reversing valve, the first overflow valve and the large cavity interface of the first leg oil cylinder are communicated in the selector valve.

2. The novel get-off hydraulic system as claimed in claim 1, further comprising a bidirectional hydraulic lock and a second leg cylinder, wherein a first input oil port of the bidirectional hydraulic lock is connected to the selector valve, a first output oil port of the bidirectional hydraulic lock corresponding to the first input oil port is connected to a large cavity interface of the second leg cylinder, a second input oil port of the bidirectional hydraulic lock is connected to the reversing valve, and a second output oil port of the bidirectional hydraulic lock corresponding to the second input oil port is connected to a small cavity interface of the second leg cylinder;

when the selector valve is in a first working position, the reversing valve, the first overflow valve, the oil return pipeline, the first input oil port and a large cavity interface of the first leg oil cylinder are not communicated with each other in the selector valve;

when the selector valve is in the third working position, the reversing valve is communicated with the second oil inlet in the selector valve.

3. The novel hydraulic system of getting off of claim 2, wherein the selector valve is a three-position five-way valve, and an oil inlet, an oil return port, a first working oil port, a second working oil port and a third working oil port are provided on a valve body of the selector valve, the oil inlet is connected with the reversing valve, the oil return port is connected with the oil return pipeline, the first working oil port is connected with the first input oil port, the second working oil port is connected with the first overflow valve, and the third working oil port is connected with a large cavity interface of the first leg oil cylinder.

4. The novel get-off hydraulic system as claimed in claim 3, wherein when the selector valve is in the second working position, the oil inlet, the second working oil port and the third working oil port are communicated inside the selector valve.

5. The novel hydraulic system of getting off of claim 3, wherein when the selector valve is in a third working position, the oil inlet is communicated with the first working oil port inside the selector valve.

6. The novel get-off hydraulic system as claimed in claim 3, wherein when the selector valve is in the first working position, the oil inlet, the oil return port, the first working oil port, the second working oil port and the third working oil port are not communicated with each other.

7. The novel get-off hydraulic system as claimed in any one of claims 1 to 6, further comprising an oil inlet pipeline, wherein the oil inlet pipeline is connected to an oil inlet interface of the reversing valve.

8. The novel hydraulic system of claim 7, further comprising a second overflow valve, wherein one end of the second overflow valve is connected to the oil inlet pipeline, and the other end of the second overflow valve is connected to the oil return pipeline.

9. The novel get-off hydraulic system as claimed in any one of claims 1 to 6, further comprising a hydraulic control one-way valve, wherein the small cavity port of the first leg cylinder is connected to the reversing valve through the hydraulic control one-way valve.

10. A working machine, characterized in that it comprises a new drop-off hydraulic system according to any one of claims 1-9.

Technical Field

The invention relates to the technical field of engineering machinery, in particular to a novel get-off hydraulic system and engineering machinery.

Background

In engineering machinery such as a crane, a get-off hydraulic system switches a first leg oil cylinder through a selection valve, and controls the expansion and contraction of the first leg oil cylinder through a reversing valve, so that the balanced support of the whole crane is realized.

In practical application, because the existing hydraulic system for the lower vehicle lacks the pressure bearing limit of the first leg oil cylinder, the piston rod of the first leg oil cylinder is bent and deformed due to overlarge pressure.

Disclosure of Invention

The invention aims to provide a novel hydraulic system for a get-off vehicle, which can limit the bearing of a first leg oil cylinder.

Another object of the present invention is to provide an engineering machine capable of restricting the pressure of a first leg cylinder.

The invention provides a technical scheme that:

a novel hydraulic system for a get-off vehicle comprises a selector valve, a reversing valve, a first overflow valve, an oil return pipeline and a first leg oil cylinder, wherein the selector valve is respectively connected with the reversing valve, the first overflow valve, the oil return pipeline and a large cavity interface of the first leg oil cylinder;

when the selector valve is in a first working position, the reversing valve, the first overflow valve, the oil return pipeline and a large cavity interface of the first support oil cylinder are not communicated with each other in the selector valve;

when the selector valve is in a second working position, the reversing valve, the first overflow valve and the large cavity interface of the first leg oil cylinder are communicated in the selector valve.

Furthermore, the novel get-off hydraulic system further comprises a bidirectional hydraulic lock and a second support oil cylinder, a first input oil port of the bidirectional hydraulic lock is connected with the selector valve, a first output oil port of the bidirectional hydraulic lock, which corresponds to the first input oil port, is connected with a large cavity interface of the second support oil cylinder, a second input oil port of the bidirectional hydraulic lock is connected with the reversing valve, and a second output oil port of the bidirectional hydraulic lock, which corresponds to the second input oil port, is connected with a small cavity interface of the second support oil cylinder;

when the selector valve is in a first working position, the reversing valve, the first overflow valve, the oil return pipeline, the first input oil port and a large cavity interface of the first leg oil cylinder are not communicated with each other in the selector valve;

when the selector valve is in the third working position, the reversing valve is communicated with the second oil inlet in the selector valve.

Furthermore, the selector valve is a three-position five-way valve, an oil inlet, an oil return port, a first working oil port, a second working oil port and a third working oil port are arranged on a valve body of the selector valve, the oil inlet is connected with the reversing valve, the oil return port is connected with the oil return pipeline, the first working oil port is connected with the first input oil port, the second working oil port is connected with the first overflow valve, and the third working oil port is connected with a large cavity interface of the first leg oil cylinder.

Further, when the selector valve is located at a second working position, the oil inlet, the second working oil port and the third working oil port are communicated in the selector valve.

Further, when the selector valve is located at a third working position, the oil inlet is communicated with the first working oil port in the selector valve.

Further, when the selector valve is located at the first working position, the oil inlet, the oil return port, the first working oil port, the second working oil port and the third working oil port are not communicated with each other.

Further, novel hydraulic system of getting off still includes into oil pipe way, advance oil pipe way with the oil feed interface connection of switching-over valve.

Further, novel hydraulic system of getting off still includes the second overflow valve, the one end of second overflow valve with advance oil pipe way and connect, the other end of second overflow valve with return oil pipe way and connect.

Furthermore, the novel get-off hydraulic system further comprises a hydraulic control one-way valve, and a small cavity interface of the first leg oil cylinder is connected with the reversing valve through the hydraulic control one-way valve.

The invention also provides engineering machinery comprising the novel get-off hydraulic system, wherein the novel get-off hydraulic system comprises a selector valve, a reversing valve, a first overflow valve, an oil return pipeline and a first leg oil cylinder, the selector valve is respectively connected with the reversing valve, the first overflow valve, the oil return pipeline and a large cavity interface of the first leg oil cylinder, the oil return pipeline is also respectively connected with the reversing valve and the first overflow valve, and a small cavity interface of the first leg oil cylinder is connected with the reversing valve; when the selector valve is in a first working position, the reversing valve, the first overflow valve, the oil return pipeline and a large cavity interface of the first leg oil cylinder are not communicated with each other; when the selector valve is in a second working position, the reversing valve, the first overflow valve and the large cavity interface of the first leg oil cylinder are communicated in the selector valve.

Compared with the prior art, according to the novel get-off hydraulic system provided by the invention, when the selector valve is in the second working position, the reversing valve, the first overflow valve and the large cavity interface of the first leg oil cylinder are communicated in the selector valve. Therefore, in practical application, when the selector valve is in the second working position, the reversing valve inputs hydraulic oil to the large cavity interface of the first leg oil cylinder, the oil pressure in the large cavity of the first leg oil cylinder is controlled by the first overflow valve, and when the oil pressure exceeds the set value of the first overflow valve, the first overflow valve communicates the large cavity of the first leg oil cylinder with the oil return pipeline to realize pressure relief. Therefore, the novel get-off hydraulic system provided by the invention has the beneficial effects that: the first support oil cylinder can be limited in pressure bearing, and deformation and damage of the first support oil cylinder due to overlarge pressure bearing are prevented.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments will be briefly described below. It is appreciated that the following drawings depict only certain embodiments of the invention and are therefore not to be considered limiting of its scope. For a person skilled in the art, it is possible to derive other relevant figures from these figures without inventive effort.

Fig. 1 is a schematic structural diagram of a novel get-off hydraulic system provided by a first embodiment of the invention;

fig. 2 is a schematic view of the selector valve of fig. 1.

Icon: 100-a novel get-off hydraulic system; 110-a selector valve; 111-an oil inlet; 113-oil return port; 115-a first working oil port; 117-second working oil port; 119-a third working oil port; 120-a diverter valve; 130-a first relief valve; 140-return line; 150-a first leg cylinder; 160-oil inlet pipeline; 170-a second overflow valve; 180-hydraulic control check valve; 185-bidirectional hydraulic lock; 190-second leg cylinder.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. 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.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "inside", "outside", "left", "right", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, or the orientations or positional relationships that the products of the present invention are conventionally placed in use, or the orientations or positional relationships that are conventionally understood by those skilled in the art, and are used for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is also to be noted that, unless otherwise explicitly stated or limited, the terms "disposed" and "connected" are to be interpreted broadly, and for example, "connected" may be a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; the connection may be direct or indirect via an intermediate medium, and may be a communication between the two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The following detailed description of embodiments of the invention refers to the accompanying drawings.

First embodiment

Referring to fig. 1, the novel get-off hydraulic system 100 provided in this embodiment is applied to a crane, and can limit the pressure of the first leg cylinder 150, so as to prevent the first leg cylinder 150 from being deformed and damaged due to too large pressure.

The novel get-off hydraulic system 100 provided by this embodiment includes a selector valve 110, a reversing valve 120, a first overflow valve 130, an oil return line 140, a first leg cylinder 150, an oil inlet line 160, a second overflow valve 170, a hydraulic control check valve 180, a bidirectional hydraulic lock 185, and a second leg cylinder 190.

The selector valve 110 is respectively connected with the reversing valve 120, one end of the first overflow valve 130, the oil return pipeline 140, a large cavity interface of the first leg cylinder 150 and a first input interface of the bidirectional hydraulic lock 185, the oil return pipeline 140 is respectively connected with the reversing valve 120 and the other end of the first overflow valve 130, a small cavity interface of the first leg cylinder 150 and a second input interface of the bidirectional hydraulic lock 185 are connected with the reversing valve 120 through a hydraulic control one-way valve 180, a first output interface of the bidirectional hydraulic lock 185, which corresponds to the first input interface, is connected with a large cavity interface of the second leg cylinder 190, and a second output interface of the bidirectional hydraulic lock 185, which corresponds to the second input interface, is connected with a small cavity interface of the second leg cylinder 190.

It should be noted that the large cavity interface of the first leg cylinder 150 is communicated with the rodless cavity of the first leg cylinder 150, the small cavity interface of the first leg cylinder 150 is communicated with the rod cavity of the first leg cylinder 150, the large cavity interface of the second leg cylinder 190 is communicated with the rodless cavity of the second leg cylinder 190, and the small cavity interface of the second leg cylinder 190 is communicated with the rod cavity of the second leg cylinder 190.

In this embodiment, the number of the selector valve 110, the first leg cylinder 150, the two-way hydraulic lock 185, and the second leg cylinder 190 is two, and in other embodiments, the number of the selector valve 110, the first leg cylinder 150, the two-way hydraulic lock 185, and the second leg cylinder 190 may also be adaptively adjusted according to actual application requirements.

Referring to fig. 1 and 2, in this embodiment, the selector valve 110 is an improved three-position five-way valve, a valve body of the selector valve 110 is provided with an oil inlet 111, an oil return port 113, a first working oil port 115, a second working oil port 117, and a third working oil port 119, the oil inlet 111 is connected to the selector valve 120 for inputting the hydraulic oil output from the selector valve 120, the oil return port 113 is connected to the oil return pipeline 140, the first working oil port 115 is connected to the first input interface of the bi-directional hydraulic lock 185, the second working oil port 117 is connected to one end of the first relief valve 130, and the third working oil port 119 is connected to the corresponding large cavity interface of the first leg cylinder 150.

In practical application, the two first leg cylinders 150 and the two second leg cylinders 190 are respectively controlled by operating the two selector valves 110 to switch the working positions. When the selector valve 110 is in the first working position, the oil inlet 111, the oil return port 113, the first working port 115, the second working port 117, and the third working port 119 are not communicated with each other. That is, the reversing valve 120, the first overflow valve 130, the oil return line 140, the corresponding large-cavity port of the first leg cylinder 150, and the corresponding large-cavity port of the second leg cylinder 190 are not communicated with each other. That is, the first leg cylinder 150 and the second leg cylinder 190 corresponding to the selector valve 110 do not operate.

When any selector valve 110 is in the second working position, the oil inlet 111, the second working oil port 117 and the third working oil port 119 are communicated inside the selector valve 110. That is, the selector valve 110 is communicated with the large-cavity ports of the first overflow valve 130 and the corresponding first leg cylinder 150, and the first leg cylinder 150 corresponding to the selector valve 110 operates to control the hydraulic oil input to the first leg cylinder 150 by switching the operating position of the selector valve 120.

When the selector valve 110 is in the second operating position, the first relief valve 130 is communicated with the oil inlet 111 and the second operating oil port 117 inside the selector valve 110, that is, the first relief valve 130 is communicated with the large cavity of the first leg cylinder 150 corresponding to the selector valve 110, and the oil pressure of the first relief valve 130 is approximately equal to the large cavity oil pressure of the first leg cylinder 150.

In practical application, when the working position of the reversing valve 120 is switched, after the hydraulic oil output by the reversing valve 120 is sequentially input into the large cavity of the first leg cylinder 150 through the oil inlet 111 and the third working oil port 119 of the reversing valve 120, the piston rod of the first leg cylinder 150 gradually extends to support the frame, and when the oil pressure of the large cavity of the first leg cylinder 150 reaches the set threshold value of the first overflow valve 130, the first overflow valve 130 conducts part of the hydraulic oil to the oil return pipeline 140 to realize pressure relief. Therefore, the pressure limiting protection of the first leg cylinder 150 can be realized by setting the threshold of the first relief valve 130 according to the critical pressure of the bending deformation of the piston rod of the first leg cylinder 150.

When the selector valve 110 is in the third working position, the oil inlet 111 and the first working oil port 115 are communicated with each other inside the selector valve 110. At this time, the hydraulic oil output from the directional valve 120 enters the second leg cylinder 190 through the first working oil port 115 and the two-way hydraulic lock 185, the second leg cylinder 190 extends, and the first leg cylinder 150 is in a balanced pressure maintaining state.

Therefore, through structural improvement of the selector valve 110, in combination with the first overflow valve 130, pressure limiting protection of the first leg cylinder 150 is achieved, and deformation of a piston rod of the first leg cylinder 150 is prevented. In practical application, compared with a mode that an overflow valve is connected with a large cavity connector of the first leg oil cylinder 150 through a one-way valve in part of engineering machinery, the negative pressure is avoided, the application cost is reduced, and the loop structure is more stable and reliable.

One end of the oil inlet pipeline 160 is connected with an oil inlet interface of the reversing valve 120 and is used for being externally connected with an oil supply device so as to supply oil to the novel get-off hydraulic system 100, one end of the second overflow valve 170 is connected with the oil inlet pipeline 160, and the other end of the second overflow valve is connected with the oil return pipeline 140. When the oil inlet pressure is too high, the second overflow valve 170 pours part of the hydraulic oil in the oil inlet pipeline 160 into the oil return pipeline 140, so that the pressure limiting effect is achieved, and safety accidents caused by the too high oil inlet pressure are avoided.

In this embodiment, the respective small cavity ports of the two first leg cylinders 150 and the respective small cavity ports of the two second leg cylinders 190 are connected to the directional control valve 120 through the pilot operated check valve 180, and when the directional control valve 120 is switched to a working position for supplying oil to the large cavity of the first leg cylinder 150, the large cavity of the first leg cylinder 150 is filled with oil to push the piston, and since the pilot operated check valve 180 is in a natural state, only hydraulic oil is supplied to flow into the small cavity of the first leg cylinder 150 through the directional control valve 120, pressure in the small cavity is gradually increased. The small cavity can be communicated with the oil return pipeline 140 by controlling the oil way to open the hydraulic control one-way valve 180, so that the pressure relief of the small cavity of the first support leg oil cylinder 150 is realized, and the pressure relief of the small cavity of the second support leg oil cylinder 190 is realized in the same way.

When the reversing valve 120 is switched to the working position for supplying oil to the small cavity of the first leg oil cylinder 150, the hydraulic oil output by the reversing valve 120 is input into the small cavity of the first leg oil cylinder 150 through the hydraulic control one-way valve 180, the hydraulic oil in the large cavity of the first leg oil cylinder 150 flows back to the reversing valve 120 through the selector valve 110, and is finally input into the oil return pipeline 140, which is the resetting process of the first leg oil cylinder 150, and the resetting process of the second leg oil cylinder 190 is the same.

The novel get-off hydraulic system 100 provided by this embodiment, through the structural improvement to the selector valve 110, combines the first overflow valve 130 to realize the pressure limiting protection to the first leg cylinder 150, prevents that the piston rod of the first leg cylinder 150 from deforming. In practical application, compared with a mode that an overflow valve is connected with a large cavity connector of the first leg oil cylinder 150 through a one-way valve in part of engineering machinery, the negative pressure is avoided, the application cost is reduced, and the loop structure is more stable and reliable.

Second embodiment

The embodiment provides a construction machine, which comprises a novel get-off hydraulic system 100 provided by the first embodiment. According to the engineering machine provided by the embodiment, the novel lower hydraulic system 100 of the engineering machine realizes the pressure limiting protection of the first leg oil cylinder 150 through the arrangement of the selection valve 110 and the first overflow valve 130, prevents the piston rod of the first leg oil cylinder 150 from deforming, greatly reduces the maintenance cost and prolongs the service life.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.