阅读说明：本技术 举升设备 (Lifting device ) 是由 杨东升 何春栋 高永胜 王永蕾 于 2021-02-05 设计创作，主要内容包括：本发明提出一种举升设备,包含本体、升降部、液压驱动系统、第一应急系统以及第二应急系统；第一应急系统包含截止阀、第一测压接头、第二测压接头以及第一测压管,截止阀的出口连接于液压驱动系统的油箱,第一测压接头连接于截止阀的进口,第二测压接头连接于举升油缸的下液压接口,第一测压管可拆装地连接于第一测压接头与第二测压接头；第二应急系统包含第三测压接头、第四测压接头、第五测压接头以及第二测压管,第三测压接头和第四测压接头分别连接于支腿油缸的液压锁安装接口的上、下接口,第五测压接头连接于液压驱动系统,第二测压管可拆装地连接于第三测压接头和第四测压接头与第五测压接头。(The invention provides lifting equipment, which comprises a body, a lifting part, a hydraulic driving system, a first emergency system and a second emergency system, wherein the lifting part is arranged on the body; the first emergency system comprises a stop valve, a first pressure measuring joint, a second pressure measuring joint and a first pressure measuring pipe, wherein an outlet of the stop valve is connected to an oil tank of the hydraulic driving system; the second emergency system comprises a third pressure measuring joint, a fourth pressure measuring joint, a fifth pressure measuring joint and a second pressure measuring pipe, the third pressure measuring joint and the fourth pressure measuring joint are respectively connected to the upper interface and the lower interface of the hydraulic lock mounting interface of the supporting leg oil cylinder, the fifth pressure measuring joint is connected to the hydraulic driving system, and the second pressure measuring pipe is detachably connected to the third pressure measuring joint, the fourth pressure measuring joint and the fifth pressure measuring joint.)

1. A lifting device comprises a body, a lifting part and a hydraulic driving system, wherein the lifting part is arranged on the body through a lifting mechanism, the lifting mechanism comprises a lifting oil cylinder, the body is provided with lifting support legs, the lifting support legs comprise support leg oil cylinders, and the hydraulic driving system is connected to the lifting oil cylinder and the support leg oil cylinders; characterized in that the lifting equipment further comprises:

the first emergency system comprises a stop valve, a first pressure measuring joint, a second pressure measuring joint and a first pressure measuring pipe, wherein an outlet of the stop valve is connected to an oil tank of the hydraulic driving system, the first pressure measuring joint is connected to an inlet of the stop valve, the second pressure measuring joint is connected to a lower hydraulic pressure joint of the lifting oil cylinder, and the first pressure measuring pipe is detachably connected to the first pressure measuring joint and the second pressure measuring joint;

the second emergency system comprises a third pressure measuring joint, a fourth pressure measuring joint, a fifth pressure measuring joint and a second pressure measuring pipe, wherein the third pressure measuring joint and the fourth pressure measuring joint are respectively connected to the upper interface and the lower interface of the hydraulic lock installation interface of the supporting leg oil cylinder, the fifth pressure measuring joint is connected to the hydraulic driving system, and the second pressure measuring pipe is detachably connected to the third pressure measuring joint and the fourth pressure measuring joint and the fifth pressure measuring joint.

2. The lifting apparatus of claim 1, wherein the shut-off valve is disposed in a first mounting block, an inlet of the first mounting block is connected to an inlet of the shut-off valve, an outlet of the first mounting block is connected to an outlet of the shut-off valve, and the first pressure sensing tube is removably connected to the inlet of the first mounting block and the second pressure sensing connector.

3. The lifting apparatus of claim 2, wherein the outlet of the first mounting block is connected to the tank via an oil return line.

4. The lifting apparatus according to claim 1, wherein the hydraulic drive system comprises a first pipeline connected to the lower hydraulic port of the lifting cylinder, the first pipeline having a first hydraulic lock disposed thereon; wherein the second pressure tap is connected between the first hydraulic lock and the lower hydraulic interface.

5. The lifting equipment as claimed in claim 4, wherein the cylinder barrel of the lifting oil cylinder is provided with a second mounting block, and the first hydraulic lock and the second pressure measuring joint are respectively connected to the second mounting block and are respectively connected to the lower hydraulic interface of the lifting oil cylinder through the second mounting block.

6. The lifting apparatus according to claim 1, wherein the hydraulic drive system comprises a second pipeline and a third pipeline, the second pipeline and the third pipeline are respectively connected to the upper and lower ports of the hydraulic lock mounting port, the second pipeline is provided with a second hydraulic lock, and the third pipeline is provided with a third hydraulic lock; the third pressure measuring joint is connected to the upper interface, the fourth pressure measuring joint is connected to the lower interface, and the fifth pressure measuring joint is connected to the second pipeline or the third pipeline.

7. The lifting device according to claim 1, wherein the hydraulic lock mounting interface is disposed at an upper portion of the cylinder barrel of the leg cylinder, an upper interface of the hydraulic lock mounting interface is connected to an upper hydraulic interface of the cylinder barrel of the leg cylinder, and the lower interface is connected to a lower hydraulic interface of the cylinder barrel of the leg cylinder through a connecting pipe.

8. The lifting apparatus of claim 1, wherein the shut-off valve is a ball valve.

9. The lifting apparatus according to claim 1, wherein the first pressure measuring tube is a hose; and/or the second piezometric tube is a hose.

10. The lifting apparatus according to claim 1, wherein the leg base of the leg cylinder is provided with an emergency operation hole for a user to retract the cylinder rod of the leg cylinder by passing an operation rod through the emergency operation hole when the second pressure measuring pipe is connected to the third pressure measuring joint and the fourth pressure measuring joint and the fifth pressure measuring joint.

Technical Field

The invention relates to lifting equipment.

Background

The lifting device is applied to various fields, such as aviation food vehicles in the field of airport special vehicles, is specially used for catering of flights, and ensures that the flights depart on time. In order to ensure the punctuality of the flights, users have very high requirements on the working reliability and the emergency evacuation efficiency of the aviation food vehicles. The operational reliability of the aircraft food vehicle needs to be guaranteed by the reliable operation of mechanical, electrical and hydraulic components. Due to safety requirements, the motion control of mechanical and hydraulic components is realized by an electrical system, and the motion control of various components is designed with a plurality of logic interlocking functions, so that the food cart and flight danger caused by misoperation is prevented.

Emergency evacuation procedures for lifting equipment such as air food vehicles typically involve: the four-way platform retracts to the right position → the box body descends to the right position → the supporting legs retract to the right position → the food cart drives away from the catering machine. Normally, only after the previous step in the above steps is completed, the subsequent steps can be executed (for example, it can be realized by an electric logic interlock function). However, in special cases, unconventional operation can be carried out, so that the food car is evacuated from the catering machine position as soon as possible, and the punctuality of the flight is guaranteed. For example, some existing aircraft food cart electrical systems are provided with an override switch, and when the override switch is turned on, the electrical interlock function is fully disabled, thereby facilitating emergency evacuation of the food cart.

The emergency evacuation mode of the existing aviation food vehicle generally comprises an electric emergency pump evacuation operation and a manual pump evacuation operation. However, in actual use and operation, the problem that the electric emergency pump is removed and the manual emergency pump is removed simultaneously to be failed is encountered, and at the moment, the carriage body of the aviation food car can be at a certain height and the supporting leg oil cylinder is supported on the ground, so that the operation of turning on the electric overrunning switch and towing or driving away from the catering machine position cannot be carried out.

Disclosure of Invention

It is a primary object of the present invention to overcome at least one of the above-mentioned deficiencies of the prior art and to provide a lift device with emergency evacuation functionality in the event of failure of electric emergency pump evacuation and manual pump evacuation.

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

according to one aspect of the invention, a lifting device is provided, which comprises a body, a lifting part and a hydraulic driving system, wherein the lifting part is arranged on the body through a lifting mechanism, the lifting mechanism comprises a lifting oil cylinder, the body is provided with lifting legs, the lifting legs comprise leg oil cylinders, and the hydraulic driving system is connected to the lifting oil cylinder and the leg oil cylinders; the lifting equipment further comprises a first emergency system and a second emergency system; the first emergency system comprises a stop valve, a first pressure measuring joint, a second pressure measuring joint and a first pressure measuring pipe, wherein an outlet of the stop valve is connected to an oil tank of the hydraulic driving system, the first pressure measuring joint is connected to an inlet of the stop valve, the second pressure measuring joint is connected to a lower hydraulic pressure joint of the lifting oil cylinder, and the first pressure measuring pipe is detachably connected to the first pressure measuring joint and the second pressure measuring joint; the second emergency system comprises a third pressure measuring joint, a fourth pressure measuring joint, a fifth pressure measuring joint and a second pressure measuring pipe, wherein the third pressure measuring joint and the fourth pressure measuring joint are respectively connected to the upper interface and the lower interface of the hydraulic lock installation interface of the supporting leg oil cylinder, the fifth pressure measuring joint is connected to the hydraulic driving system, and the second pressure measuring pipe is detachably connected to the third pressure measuring joint and the fourth pressure measuring joint and the fifth pressure measuring joint.

According to one embodiment of the present invention, the shutoff valve is provided in a first mounting block, an inlet of the first mounting block is connected to an inlet of the shutoff valve, an outlet of the first mounting block is connected to an outlet of the shutoff valve, and the first pressure measuring pipe is detachably connected to the inlet of the first mounting block and the second pressure measuring joint.

According to one embodiment of the invention, the outlet of the first mounting block is connected to the oil tank by an oil return line.

According to one embodiment of the invention, the hydraulic drive system comprises a first pipeline, a second pipeline and a third pipeline, wherein the first pipeline is connected to a lower hydraulic pressure port of the lifting oil cylinder, and a first hydraulic lock is arranged on the first pipeline; wherein the second pressure tap is connected between the first hydraulic lock and the lower hydraulic interface.

According to one embodiment of the invention, the cylinder barrel of the lifting oil cylinder is provided with a second mounting block, and the first hydraulic lock and the second pressure measuring joint are respectively connected to the second mounting block and are respectively connected to the lower hydraulic interface of the lifting oil cylinder through the second mounting block.

According to one embodiment of the present invention, the hydraulic drive system includes a second pipeline and a third pipeline, the second pipeline and the third pipeline are respectively connected to the upper and lower ports of the hydraulic lock installation port, the second pipeline is provided with a second hydraulic lock, and the third pipeline is provided with a third hydraulic lock; the third pressure measuring joint is arranged on the second pipeline and is positioned between the second hydraulic lock and the hydraulic lock installation interface, the fourth pressure measuring joint is arranged on the third pipeline and is positioned between the third hydraulic lock and the hydraulic lock installation interface, and the fifth pressure measuring joint is connected to the second pipeline or the third pipeline.

According to one embodiment of the invention, the hydraulic lock mounting interface is arranged at the upper part of the cylinder barrel of the landing leg oil cylinder, the upper interface of the hydraulic lock mounting interface is connected to the upper hydraulic interface of the cylinder barrel of the landing leg oil cylinder, and the lower interface is connected to the lower hydraulic interface of the cylinder barrel of the landing leg oil cylinder through a connecting pipe.

According to one embodiment of the invention, the shut-off valve is a ball valve.

According to one embodiment of the invention, the first pressure measuring tube is a hose; and/or the second piezometric tube is a hose.

According to one embodiment of the invention, the base of the support oil cylinder is provided with an emergency operation hole for a user to retract the cylinder rod of the support oil cylinder through an operation rod penetrating through the emergency operation hole when the second pressure measuring pipe is connected to the third pressure measuring joint and the fourth pressure measuring joint and the fifth pressure measuring joint.

According to the technical scheme, the lifting equipment provided by the invention has the advantages and positive effects that:

according to the lifting equipment provided by the invention, the pressure measuring joints are respectively arranged on the oil cylinder and the hydraulic driving system and are detachably matched with the pressure measuring pipes, so that the pressure measuring joints are not connected with the pressure measuring pipes and are in a closed state when the lifting equipment works normally, and the lifting equipment can be connected with the pressure measuring joints through the pressure measuring pipes when an electric emergency pump is evacuated and a manual pump is evacuated to fail and emergency evacuation is required, so that the pressure measuring joints are opened, the oil cylinder can release pressure to the hydraulic driving system through the pressure measuring pipes, the emergency evacuation operation is realized, and the lifting equipment and the hydraulic driving system thereof can be recovered to a normal working state after the pressure measuring pipes are removed.

Drawings

Various objects, features and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, when considered in conjunction with the accompanying drawings. The drawings are merely exemplary of the invention and are not necessarily drawn to scale. In the drawings, like reference characters designate the same or similar parts throughout the different views. Wherein:

FIG. 1 is a system diagram illustrating a portion of a hydraulic drive system and a first emergency system of a lifting apparatus in accordance with an exemplary embodiment;

FIG. 2 is a system schematic of another portion of a hydraulic drive system and a second emergency system of a lifting apparatus according to an exemplary embodiment;

FIG. 3 is a schematic view of a lift cylinder of the lifting apparatus shown in FIG. 1;

FIG. 4 is a bottom view of FIG. 3;

FIG. 5 is a schematic structural diagram of a leg cylinder of the lifting apparatus shown in FIG. 2;

FIG. 6 is a right side view of FIG. 5;

FIG. 7 is a top view of FIG. 5;

FIG. 8 is a schematic diagram of a lever of a lifting apparatus according to an exemplary embodiment.

The reference numerals are explained below:

100. lifting the oil cylinder;

110. a first cylinder;

111. a second mounting block;

120. a first cylinder rod;

200. a support oil cylinder;

210. a second cylinder;

220. a second cylinder rod;

230. a hydraulic lock mounting interface;

231. a connecting pipe;

240. a leg base;

250. an emergency operation hole;

251. an operating lever;

310. a stop valve;

320. a first pressure tap;

330. a second pressure tap;

340. a first pressure measuring pipe;

350. a first mounting block;

351. an oil return line;

410. a third pressure tap;

420. a fourth pressure tap;

430. a fifth pressure tap;

440. a second pressure measuring tube;

510. an oil tank;

520. a first pipeline;

521. a first hydraulic lock;

530. a second pipeline;

531. a second hydraulic lock;

540. a third pipeline;

541. and a third hydraulic lock.

Detailed Description

Exemplary embodiments that embody features and advantages of the invention are described in detail below. It is to be understood that the invention is capable of other and different embodiments and its several details are capable of modification without departing from the scope of the invention, and that the description and drawings are accordingly to be regarded as illustrative in nature and not as restrictive.

In the following description of various exemplary embodiments of the invention, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various exemplary structures, systems, and steps in which aspects of the invention may be practiced. It is to be understood that other specific arrangements of parts, structures, example devices, systems, and steps may be utilized and structural and functional modifications may be made without departing from the scope of the present invention. Moreover, although the terms "over," "between," "within," and the like may be used in this specification to describe various example features and elements of the invention, these terms are used herein for convenience only, e.g., in accordance with the orientation of the examples described in the figures. Nothing in this specification should be construed as requiring a specific three dimensional orientation of structures in order to fall within the scope of the invention.

Referring to FIG. 1, a system diagram of a portion of a hydraulic drive system and a first emergency system of a lifting apparatus of the present disclosure is representatively illustrated. In the exemplary embodiment, the lifting device proposed by the invention is illustrated by way of example in an aircraft food cart. It will be readily appreciated by those skilled in the art that numerous modifications, additions, substitutions, deletions, or other changes may be made to the embodiments described below in order to adapt the relevant design of the present invention to other types of lifting apparatus, and such changes are within the scope of the principles of the lifting apparatus as set forth herein.

As shown in fig. 1, in the present embodiment, the present invention proposes that a lifting apparatus includes a body, a lifting unit, a hydraulic drive system, a first emergency system, and a second emergency system. The lifting part is arranged on the body through a lifting mechanism, and the lifting mechanism comprises a lifting oil cylinder 100. The body is provided with lifting legs which contain leg cylinders 200. The hydraulic drive system is connected to the lift cylinder 100 and the leg cylinder 200. Referring to fig. 2-8 in combination, a system schematic of another portion of a hydraulic drive system and a second emergency system of a lifting apparatus that can embody principles of the present disclosure is representatively illustrated in fig. 2; representatively illustrated in FIG. 3 is a schematic structural view of a lift cylinder 100 of a lifting apparatus which can embody principles of this disclosure; representatively illustrated in fig. 4 is a bottom view of fig. 3; representatively illustrated in fig. 5 is a schematic structural view of a leg cylinder 200 of a lifting apparatus which can embody principles of this disclosure; representatively illustrated in fig. 6 is a right side view of fig. 5; representatively illustrated in fig. 7 is a top view of fig. 5; a schematic structural view of the operating lever 251 of a lifting device that can embody principles of the present invention is representatively illustrated in fig. 8. The structural connection and functional relationship of the main components of the lifting device proposed by the present invention will be described below with reference to the above-mentioned drawings.

In the above description, the body and the lifting portion of the lifting device can be understood as the body and the compartment of the aircraft food vehicle, respectively, taking the aircraft food vehicle as an example. Also, the lift mechanism may be understood as a lift device such as a lift fork of an air food vehicle, and the lift cylinder 100 may be understood as a cylinder of the lift fork.

As shown in fig. 1 and 2, in the present embodiment, the first emergency system includes a shut-off valve 310, a first pressure tap 320, a second pressure tap 330, and a first pressure tap 340. The outlet of the shut-off valve 310 is connected to the tank 510 of the hydraulic drive system. The first pressure tap 320 is connected to the inlet of the shut-off valve 310. The second pressure tap 330 is connected to the lower hydraulic port of the lift cylinder 100. The first pressure tube 340 is removably connected to the first pressure tap 320 and the second pressure tap 330. Furthermore, the second emergency system includes a third pressure tap 410, a fourth pressure tap 420, a fifth pressure tap 430, and a second pressure tap 440. The third pressure measuring tap 410 and the fourth pressure measuring tap 420 are connected to upper and lower ports of the hydraulic lock installation port 230 of the leg cylinder 200, respectively. The fifth pressure tap 430 is connected to the hydraulic drive system. The second pressure tube 440 is removably connected to the third pressure tap 410 and the fourth and fifth pressure taps 420 and 430.

Through the design, the pressure measuring joint is not connected with the pressure measuring pipe and is in a closed state when the lifting equipment normally works, the lifting equipment is enabled to be connected with the pressure measuring joint through the pressure measuring pipe when the electric emergency pump is evacuated and the manual pump is evacuated to be invalid and needs emergency evacuation, the opening of the pressure measuring joint is realized, so that the oil cylinder can release pressure to the hydraulic driving system through the pressure measuring pipe, the emergency evacuation operation is realized, and the lifting equipment and the hydraulic driving system thereof can be enabled to recover the normal working state after the pressure measuring pipe is removed. Therefore, the lifting equipment provided by the invention has an emergency evacuation function when the electric emergency pump evacuation and the manual pump evacuation are failed.

Alternatively, as shown in fig. 1, in the present embodiment, the shut valve 310 may be provided on the first mounting block 350. In particular, the first mounting block 350 may be provided on the body or other fixed structure of the lifting device. When the shut valve 310 is mounted to the first mounting block 350, an inlet of the first mounting block 350 is connected to an inlet of the shut valve 310, and an outlet of the first mounting block 350 is connected to an outlet of the shut valve 310. On this basis, the first pressure measuring tube 340 is removably connected to the inlet of the first mounting block 350 and the second pressure measuring tap 330.

Further, as shown in fig. 1, based on the design in which the shut valve 310 is provided to the first mounting block 350, in the present embodiment, the outlet of the first mounting block 350 may be connected to the oil tank 510 through the oil return line 351.

Further, as shown in fig. 1, the shut valve 310 may be mounted on the first mounting block 350 by a plate type connection in the present embodiment, based on the design that the shut valve 310 is provided on the first mounting block 350.

Alternatively, as shown in fig. 1, in the present embodiment, the hydraulic drive system may include a first pipeline 520, the first pipeline 520 is connected to the lower hydraulic pressure port of the lift cylinder 100, and a first hydraulic lock 521 is disposed on the first pipeline 520. On this basis, a second pressure tap 330 may be connected at a position between the first hydraulic lock 521 and the lower hydraulic port of the lift cylinder 100.

Further, as shown in fig. 1, 3 and 4, based on the design in which the first pipe 520 is provided with the first hydraulic lock 521, in the present embodiment, the first cylinder 110 of the lift cylinder 100 may be provided with the second mounting block 111. On this basis, the first hydraulic lock 521 and the second pressure measuring joint 330 may be respectively connected to the second mounting block 111, and the first hydraulic lock 521 and the second pressure measuring joint 330 may be respectively connected to the lower hydraulic interface of the lift cylinder 100 through the second mounting block 111.

Alternatively, as shown in fig. 2, in the present embodiment, the hydraulic driving system may include a second pipeline 530 and a third pipeline 540, the second pipeline 530 is connected to the upper interface of the hydraulic lock mounting interface 230, the third pipeline 540 is connected to the lower interface of the hydraulic lock mounting interface 230, a second hydraulic lock 531 is disposed on the second pipeline 530, and a third hydraulic lock 541 is disposed on the third pipeline 540. On this basis, the third pressure tap 410 may be connected between the second hydraulic lock 531 and the upper interface of the hydraulic lock mounting interface 230, and the fourth pressure tap 420 may be connected between the third hydraulic lock 541 and the lower interface of the hydraulic lock mounting interface 230. Also, the fifth pressure tap 430 may be connected to the second pipe 530 or the third pipe 540.

Further, as shown in fig. 2, based on the design that the hydraulic driving system includes the second pipeline 530 and the third pipeline 540, in this embodiment, one end of the second pressure measuring pipe 440 may include two end branch pipes connected in parallel, and the second pressure measuring pipe 440 may be detachably connected to the third pressure measuring joint 410 and the fourth pressure measuring joint 420 through the two end branch pipes, respectively. The other end of the second pressure measuring pipe 440 may have a single pipe structure and may be detachably connected to one of the second pipe 530 and the third pipe 540.

Alternatively, as shown in fig. 2, 5 to 7, in the present embodiment, the hydraulic lock mounting interface 230 may be provided at an upper portion of the second cylinder 210 of the leg cylinder 200, and the hydraulic lock mounting interface 230 has an upper interface that may be connected to an upper hydraulic interface of the second cylinder 210 of the leg cylinder 200 and a lower interface that may be connected to a lower hydraulic interface of the second cylinder 210 of the leg cylinder 200 through a connection pipe 231.

Alternatively, in this embodiment, the stop valve 310 may be a ball valve.

Alternatively, in this embodiment, the first piezometric tube 340 may be a flexible tube.

Alternatively, in this embodiment, the second piezometric tube 440 can be a flexible tube.

Alternatively, as shown in fig. 5, 6 and 8, in the present embodiment, the base of the leg cylinder 200 may be provided with an emergency operation hole 250. Accordingly, through the design of the emergency operation hole 250, the present invention enables the user to retract the second rod 220 of the leg cylinder 200 by inserting the operation rod 251 through the emergency operation hole 250 when the second pressure measuring pipe 440 is connected to the third pressure measuring joint 410 and the fourth pressure measuring joint 420 and the fifth pressure measuring joint 430.

Based on the above detailed description of an exemplary embodiment of the lifting apparatus proposed by the present invention, the working principle and flow of the lifting apparatus proposed by the present invention will be described below.

When the lifting part (such as a carriage) fails to descend in the electric emergency operation and the manual emergency operation, the first piezometer tube 340 is used for connecting the first piezometer connector 320 on the first mounting block 350 and the second piezometer connector 330 on the second mounting block 111 (normally, the piezometer hose is not connected), then the stop valve 310 is opened, the hydraulic oil in the first cylinder barrel 110 of the lifting oil cylinder 100 flows back to the oil tank 510 of the hydraulic driving system, the first cylinder rod 120 of the lifting oil cylinder 100 is retracted under the gravity action of the lifting part, and the lifting part descends slowly, so that the emergency descending of the lifting part is realized. After the emergency descending action of the lifting part is completed, the first piezometer tube 340 is detached, and the hydraulic driving system drives a part of hydraulic circuits of the lifting part to ascend and descend to recover to a normal state.

When the retraction of the lifting leg for the electric emergency operation and the manual emergency operation fails, the third pressure measuring joint 410, the fourth pressure measuring joint 420 and the fifth pressure measuring joint 430 are connected using the second pressure measuring pipe 440, and then inserted into the emergency operation hole 250 of the leg base 240 of the leg cylinder 200 using the operation rod 251, and the second cylinder rod 220 of the leg cylinder 200 is retracted using a manual force. Each leg cylinder 200 performs leg retraction in the same manner. After the emergency retraction action of all the supporting leg oil cylinders 200 is completed, the second pressure measuring hose is detached, and the hydraulic driving system drives a part of the hydraulic loop of the lifting supporting leg to ascend and descend to recover to a normal state.

By the above emergency operation, the lifting unit can be lowered to the lowest position, and the second rod 220 of each leg cylinder 200 can be fully retracted. In emergency operation, for example, if the four-way platform is docked with an airplane, after all the leg cylinders 200 are retracted, the electric cross switch is operated to drive the food cart away from the airplane slowly and then to pull the food cart or drive the food cart away from the catering location.

It should be noted here that the lifting devices shown in the drawings and described in this specification are only a few examples of the many types of lifting devices that can employ the principles of the present invention. It should be clearly understood that the principles of the present invention are in no way limited to any details or any components of the lifting device shown in the drawings or described in this specification.

For example, as shown in fig. 1, in the present embodiment, taking an aviation food cart as an example, it may include two lift cylinders 100. On this basis, two sets of first emergency systems may be provided corresponding to the two lift cylinders 100, respectively, and the two stop valves 310 of the two sets of first emergency systems may be installed at the same position, for example, on the same first installation block 350.

As another example, as shown in fig. 2, in the present embodiment, taking an aviation food cart as an example, the leg cylinders 200 may be arranged in pairs, and may include at least two pairs. On this basis, a plurality of groups of second emergency systems can be respectively arranged corresponding to the plurality of supporting leg oil cylinders 200.

As shown in fig. 3 and 4, in the present embodiment, the lift cylinder 100 includes a first cylinder and a first lever that is extendable and retractable from a distal end of the first cylinder. Also, the leg cylinder 200 may include a second cylinder body and a second cylinder rod 220, and the second lever may be extended and contracted from a bottom end of the second cylinder body.

In summary, according to the lifting device provided by the invention, the pressure measuring joints are respectively arranged on the oil cylinder and the hydraulic driving system, and are detachably matched with the pressure measuring pipe, so that the pressure measuring joints are not connected with the pressure measuring pipe and are in a closed state when the lifting device normally works, and when the lifting device needs emergency evacuation due to failure of electric emergency pump evacuation and manual pump evacuation, the pressure measuring joints can be connected with the pressure measuring joints through the pressure measuring pipe to open the pressure measuring joints, so that the oil cylinder can release pressure to the hydraulic driving system through the pressure measuring pipe, the emergency evacuation operation is realized, and the lifting device and the hydraulic driving system thereof can be restored to a normal working state after the pressure measuring pipe is removed.

Moreover, compared with the existing scheme, the lifting equipment provided by the invention can improve the reliability and the working efficiency of emergency evacuation. In the existing scheme, when the electric emergency pump evacuation scheme and the manual emergency scheme fail, the hydraulic locks on the supporting leg oil cylinder and the lifting oil cylinder can be detached one by one only through manual operation, and the lifting part is difficult to operate and has potential safety hazards when in a high position. The manual disassembly has low working efficiency and certain danger, and high-pressure oil can be sprayed out to cause personnel injury and airport ground pollution in the disassembly process. Therefore, the lifting part can be safely lowered and the supporting leg oil cylinder can be retracted under any condition, and the leakage of hydraulic oil cannot be caused to pollute the ground of the airport.

In addition, the lifting equipment provided by the invention has the characteristics of simple operation, safety and reliability when in emergency operation, and can effectively avoid the problems of various risks caused by the disassembly of a hydraulic lock and delayed flight due to the failure of an electric pump emergency and a manual pump emergency when the aviation food vehicle is emergently evacuated.

Exemplary embodiments of the lifting device proposed by the present invention are described and/or illustrated in detail above. Embodiments of the invention are not limited to the specific embodiments described herein, but rather, components and/or steps of each embodiment may be utilized independently and separately from other components and/or steps described herein. Each component and/or step of one embodiment can also be used in combination with other components and/or steps of other embodiments. When introducing elements/components/etc. described and/or illustrated herein, the articles "a," "an," and "the" are intended to mean that there are one or more of the elements/components/etc. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. other than the listed elements/components/etc. Furthermore, the terms "first" and "second" and the like in the claims and the description are used merely as labels, and are not numerical limitations of their objects.

While the lifting apparatus of the present invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.