阅读说明：本技术 一种随车起重机专用带过桥功能的比例阀 (Special proportional valve with bridge passing function for lorry-mounted crane ) 是由 侯现元 于 2021-04-08 设计创作，主要内容包括：本发明公开了一种随车起重机专用带过桥功能的比例阀,该随车起重机专用带过桥功能的比例阀的内部设有第一通道、梭阀、第二通道、第三通道、LS1油道、LS2油道以及节流阀,该随车起重机专用带过桥功能的比例阀的左侧设有P口,该随车起重机专用带过桥功能的比例阀的右侧设有C口。随车起重机专用带过桥功能的比例阀,解决了目前存在的问题,可实现上车阀和下车阀的灵活、自动的切换；通过固定过桥口的流量,实现了上车阀和下车阀的流量匹配,同时满足上车阀和下车阀的流量需求；在有多余的流量时,多余的流量经上车比例阀的三通流量阀直接回油,压力损失小,系统发热量低；上车阀动作时,下车阀就不能动作,保证了上车操作的安全性。(The invention discloses a special proportional valve with a bridge passing function for a lorry-mounted crane, wherein a first channel, a shuttle valve, a second channel, a third channel, an LS1 oil duct, an LS2 oil duct and a throttle valve are arranged in the special proportional valve with the bridge passing function for the lorry-mounted crane, a P port is arranged on the left side of the special proportional valve with the bridge passing function for the lorry-mounted crane, and a C port is arranged on the right side of the special proportional valve with the bridge passing function for the lorry-mounted crane. The special proportional valve with the bridge passing function for the lorry-mounted crane solves the problems existing at present, and can realize flexible and automatic switching of an upper vehicle valve and a lower vehicle valve; the flow matching of the upper vehicle valve and the lower vehicle valve is realized by fixing the flow of the bridge opening, and the flow requirements of the upper vehicle valve and the lower vehicle valve are met; when redundant flow exists, the redundant flow directly returns oil through the three-way flow valve of the upper proportional valve, the pressure loss is small, and the heat productivity of the system is low; when the getting-on valve acts, the getting-off valve cannot act, and the safety of getting-on operation is ensured.)

1. The utility model provides a special proportional valve who takes bridge function of lorry crane which characterized in that: the special proportional valve with the bridging function for the lorry-mounted crane is internally provided with a first channel (1), a shuttle valve (2), a second channel (3), a third channel (4), an LS1 oil duct (5), an LS2 oil duct (6) and a throttle valve (7), the left side of the special proportional valve with the bridging function for the lorry-mounted crane is provided with a P port, and the right side of the special proportional valve with the bridging function for the lorry-mounted crane is provided with a C port.

2. The operation process of the proportional valve with the gap bridge function special for the lorry-mounted crane is characterized by comprising the following steps of:

s1: firstly, when the lorry-mounted crane does not work, the proportional valve with the bridge passing function is positioned at a middle position, at the moment, the channel (4) is communicated with the port P and the port C of the bridge passing port, then the proportional valve is fed to the shuttle valve (2) through the LS2 oil duct (6) and then fed back to the three-way flow valve, so that the port C outputs constant flow to match the requirement of the lower valve on the flow, and the hydraulic oil passes through the first channel (1) and the third channel (4) and then reaches the throttle valve (7);

s2: when the lorry-mounted crane works on the train, the proportional valve with the 'bridge passing' function is in the direction changing position, no matter which train of the loading valve works, the third channel (4) of the port P and the port C is cut off, and the port C does not have flow at the moment, namely the unloading cannot be carried out when the loading crane acts, so that the operation safety of the lorry-mounted crane is ensured in principle, and the safety accident is effectively prevented.

3. The operation process of the proportional valve with the bridge passing function special for the lorry-mounted crane according to claim 2 is characterized in that: the special proportional valve with the bridge passing function for the lorry-mounted crane comprises a plurality of working links, wherein a first channel (1), a second channel (3) and a third channel (4) are arranged in each working link.

Technical Field

The invention is used for the lorry-mounted crane, and realizes the 'bridge passing' function of the upper vehicle proportional valve of the lorry-mounted crane by designing the 'bridge passing' function, namely, when the upper vehicle proportional valve is in an inoperative state, hydraulic oil with constant flow flows out through the 'bridge passing' port of the upper vehicle proportional valve and is used as an oil source of other hydraulic systems.

Background

At present, an upper vehicle proportional valve with a bridge passing function does not exist in the market of the lorry-mounted crane. At present, two modes are mainly adopted to realize the switching of an upper vehicle valve and a lower vehicle valve: one mode is that the hydraulic pump is directly connected with a lower vehicle valve and then connected with an upper vehicle proportional valve through the lower vehicle valve, when the lower vehicle valve does not work, hydraulic oil enters the upper vehicle proportional valve through the lower vehicle valve, and the lower vehicle valve does not communicate with the upper vehicle proportional valve when the lower vehicle valve works; the other mode is that a reversing ball valve is additionally arranged between the upper vehicle proportional valve and the lower vehicle proportional valve to realize the control of oil passages of the upper vehicle proportional valve and the lower vehicle proportional valve.

No matter which mode is adopted, the method has obvious defects:

when the first mode is adopted:

1. pressure and flow matching problem: the working pressure required by the getting-on action is higher than the pressure of the getting-off leg action. When the pressure is set according to the getting-off action requirement, the working pressure required by the getting-on action cannot be met, and when the overflow pressure of the getting-off valve is set according to the pressure required by the getting-on action, the requirement on a hydraulic system of the getting-off is improved, and the cost is increased; generally, the flow required by the lower valve is small, the flow required by the upper proportional valve is large, and in order to meet the flow required by the upper valve, the lower valve has to select a large flow valve, so that the cost is increased;

2. power loss and system heating problems: when the lorry-mounted crane does not act when getting on or off, namely the getting-on proportional valve and the getting-off valve are both positioned in the middle position, pressure oil flows to the C port of the getting-off valve through the P port of the getting-off valve, flows through the whole getting-off valve and then flows to the getting-on proportional valve, and is unloaded through the proportional valve. At the moment, the unloading flow is large, the pressure loss is high after passing through a lower car valve, the power loss of a hydraulic system is caused, the system is heated, and a series of hydraulic system problems such as low efficiency are caused;

3. safety problems are as follows: when the upper car valve is operated, the lower car valve can be operated, and in the moment of operating the lower car valve, an oil path of the upper car valve is cut off suddenly, so that great impact can be brought, the whole car of the lorry-mounted crane is rocked, and potential safety hazards are brought.

When the second mode is adopted:

1. the cost is increased: in the mode, a reversing ball valve and a related hydraulic pipeline thereof are required to be added, so that the cost is increased, and the pressure loss of the system is increased;

2. the operation is inconvenient: the loading valve is generally arranged at the top end of a boom of the lorry-mounted crane, when the loading valve and the unloading valve are operated, the reversing ball valve needs to be manually operated, and under the condition of inexperience, an operator does not know which state can operate the loading valve and which state can operate the unloading valve;

3. the matching problem of the upper vehicle valve and the lower vehicle valve is as follows: the lorry-mounted crane is generally provided with a fixed displacement pump, and the output flow is fixed under the condition of a fixed rotating speed. In order to meet the flow demand of the upper vehicle valve, the flow provided by the hydraulic pump is large, and at the moment, if a lower vehicle valve adopts a small-flow valve (matched with a supporting leg oil cylinder), the pressure loss is increased when a large flow passes through the lower vehicle valve, and the system heats more quickly; if a valve with a large flow rate is selected, higher requirements are put on the installation space of the valve, and the cost is increased.

Disclosure of the invention

The invention aims to provide a special proportional valve with a bridge passing function for a lorry-mounted crane, so as to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme:

a first channel, a shuttle valve, a second channel, a third channel, an LS1 oil duct, an LS2 oil duct and a throttle valve are arranged inside the special proportional valve with the bridge passing function for the lorry-mounted crane, a P port is formed in the left side of the special proportional valve with the bridge passing function for the lorry-mounted crane, and a C port is formed in the right side of the special proportional valve with the bridge passing function for the lorry-mounted crane.

A special proportional valve operation process with a bridge passing function for a lorry-mounted crane comprises the following steps:

s1: firstly, when the loading of the lorry-mounted crane does not work, the proportional valve with the bridge passing function is positioned at a middle position, at the moment, a channel is communicated with a port P and a port C of the bridge passing port, then the channel is led to a shuttle valve through an LS2 oil channel and then fed back to a three-way flow valve, so that the port C outputs constant flow to match the requirement of the unloading valve on the flow, and hydraulic oil flows to a throttle valve through a first channel and a third channel;

s2: when the lorry-mounted crane works on the train, the proportional valve with the 'bridge passing' function is in the direction changing position, no matter which train of the loading valve works, the third channel of the port P and the port C is cut off, and the port C does not have flow at the moment, namely the unloading cannot be carried out when the loading crane acts, so that the operation safety of the lorry-mounted crane is ensured in principle, and the safety accident is effectively prevented.

Furthermore, the special proportional valve with the bridge passing function for the lorry-mounted crane comprises a plurality of working links, and each working link is internally provided with a first channel, a second channel and a third channel.

Compared with the prior art, the invention has the beneficial effects that:

the special proportional valve with the bridge passing function for the lorry-mounted crane solves the problems existing at present, and can realize flexible and automatic switching of the upper vehicle valve and the lower vehicle valve; the flow matching of the upper vehicle valve and the lower vehicle valve is realized by fixing the flow of the bridge opening, and the flow requirements of the upper vehicle valve and the lower vehicle valve are met; when redundant flow exists, the redundant flow directly returns oil through the three-way flow valve of the upper proportional valve, the pressure loss is small, and the heat productivity of the system is low; when the getting-on valve acts, the getting-off valve cannot act, and the safety of getting-on operation is ensured.

Drawings

FIG. 1 is a schematic diagram of a proportional valve with a bridge passing function special for the lorry-mounted crane.

In the figure: 1. a first passage, 2, a shuttle valve; 3. a second channel; 4. a third channel; 5. the LS1 oil passage; 6. the LS2 oil passage; 7. a throttle valve.

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 embodiments, and all other embodiments obtained by a person of ordinary skill in the art without creative efforts based on the embodiments in the present invention belong to the protection scope of the present invention.

To facilitate an understanding of the present invention, a more complete description of the present invention is provided below with reference to the accompanying drawings. Several embodiments of the invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items

Referring to fig. 1, the present invention provides a technical solution:

a first channel 1, a shuttle valve 2, a second channel 3, a third channel 4, an LS1 oil channel 5, an LS2 oil channel 6 and a throttle valve 7 are arranged inside the special proportional valve with the bridging function for the lorry-mounted crane, a P port is formed in the left side of the special proportional valve with the bridging function for the lorry-mounted crane, and a C port is formed in the right side of the special proportional valve with the bridging function for the lorry-mounted crane.

A special proportional valve operation process with a bridge passing function for a lorry-mounted crane comprises the following steps:

s1: firstly, when the loading of the lorry-mounted crane does not work, the proportional valve with the bridge passing function is positioned at a middle position, at the moment, a channel 4 is communicated with a port P and a port C of a bridge passing port, then the port P and the port C are fed to a shuttle valve 2 through an LS2 oil duct 6 and then fed back to a three-way flow valve, so that the port C outputs constant flow to match the requirement of a unloading valve on the flow, and hydraulic oil passes through a first channel 1 and a third channel 4 to a throttle valve 7;

s2: when the lorry-mounted crane works on the train, the proportional valve with the bridge passing function is in the position changing position, the third channel 4 of the port P and the port C can be cut off no matter which train of the loading valve works, the port C does not have flow at the moment, namely the unloading cannot be carried out when the loading crane acts, the safety of the operation of the lorry-mounted crane is guaranteed in principle, and safety accidents are effectively prevented.

In order to further improve the use function of the special proportional valve with the bridge passing function for the lorry-mounted crane, the special proportional valve with the bridge passing function for the lorry-mounted crane is composed of a plurality of working links, and a first channel 1, a second channel 3 and a third channel 4 are arranged in each working link.

In conclusion, the special proportional valve with the bridge passing function for the lorry-mounted crane solves the problems existing at present, and can realize flexible and automatic switching of the upper vehicle valve and the lower vehicle valve; the flow matching of the upper vehicle valve and the lower vehicle valve is realized by fixing the flow of the 'bridge passing' port, and the flow requirements of the upper vehicle valve and the lower vehicle valve are met; when redundant flow exists, the redundant flow directly returns oil through the three-way flow valve of the upper proportional valve, the pressure loss is small, and the heat productivity of the system is low; when the getting-on valve acts, the getting-off valve cannot act, and the safety of getting-on operation is ensured.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.