DE102017100877B4 - Apparatus and method for testing fluid operated jacks - Google Patents

Abstract

Device for checking fluid-actuated lifting devices (10), with a sealing device (2) which is suitable and intended for sealing off a predetermined space section (10a) of the lifting device at least temporarily, with a gas supply device (4) in order to to supply a gas to the sealed space (10a) and with a measuring device (12) which is suitable and intended for determining a pressure within the space (10a) sealed by the sealing device, the sealing device (2) having a sealing body that can be expanded by a flowable medium (22) which expands when it is acted upon by this flowable medium in such a way that a gap (Sp) of the space (10a) can be sealed in order to seal off the space (10a), and the sealing device (2) has a cover element (24 ) suitable and intended to cover a tubular body forming part of the lifting device to be checked, characterized in that the cover element (24) and the sealing body (22) are made in one piece with each other.

Description

The present invention relates to a device and a method for inspecting fluid-actuated (preferably hydraulic) lifting devices, such as lifting platforms of vehicles. Such lifting platforms have long been known from the prior art. These usually have a cassette or a built-in cylinder that can be anchored in the ground, for example. Within this cylinder is a piston assembly with the actual hydraulics. Over time, leaks can occur both in the built-in cylinder and in the actual hydraulic piston, which means that oil can escape, for example, or otherwise disruptive leaks can occur.

Methods are known from the prior art for testing such components of the lifting platform for leaks. These methods use cameras, for example, and are relatively complex.

From the DE 10 2004 043 101 A1 such a device is known. The DE 103 08 576 A1 describes an annular space seal.

The present invention is therefore based on the object of providing a device and a method which enable such lifting devices to be checked in a simpler manner. According to the invention, this object is achieved by the subject matter of the independent claims. Advantageous embodiments and developments are the subject of the dependent claims.

A device according to the invention for checking systems and in particular fluid-actuated lifting devices has a sealing device which is suitable and intended for at least temporarily sealing off a predetermined spatial section of the system and in particular lifting devices. Furthermore, the device has a gas supply device in order to supply a gas to the space sealed off by the sealing device. In addition, a measuring device is also provided, which is suitable and intended for determining a pressure within the space sealed off by the sealing device.

According to the invention, the sealing device has a (sealing) body that can be expanded by a flowable medium, which expands when it is acted upon by this flowable medium in such a way that the space section can be sealed and in particular a gap in the space section can be sealed in order to seal off the space section.

It is therefore proposed that the space, in particular the space between the aforementioned cylinder processed in the soil and the actual lifting device or the hydraulic system, is sealed and then pressurized with compressed air. The pressure within this space is monitored. If, after a certain period of time, this pressure drops more than a predetermined amount, this is an indication of the presence of a leak in the relevant space and in particular a leak either in the installation cylinder or in the actual hoist. In this way it is easy to check whether the lifting device has leaks.

It should be noted that the invention has been described herein with reference to hydraulic jacks. However, it is pointed out that the invention can also be applied to other systems and in particular to systems that have pipes carrying a fluid and in particular to hydraulically operated systems.

The invention thus allows pipe connections, pipes, objects located in a pipe, objects located in other objects, and the like to be checked and, if necessary, also rehabilitated. In addition, the tightness of manholes can also be checked. It is thus pointed out that, although the present invention is described with reference in particular to hydraulic lifting devices, the invention can also be used in other areas in which it is a question of checking the tightness of pipes, connections and the like.

In the industrial, private and municipal sectors, there is often a need for pipe-in-pipe connections, object-in-pipe connections, object-in-object connections, manhole-in-manhole connections and pipe-in-manhole - To check connections and in particular to check for leaks and then to rehabilitate them if necessary.

The invention proposes using a body that can be expanded by a flow medium to seal off this area, which body closes off the respective area or a gap that delimits this area. The flowable medium for expanding the sealing device is preferably selected from a group of flowable media which contains air, hot air, steam, water, various liquids, gas, oil, gels and the like. The sealing device is preferably a flexible element which can be expanded in particular under said pressure. The invention thus proposes a fillable Element in particular for plugging, checking and / or rehabilitating pipe-in-pipe connections and the other connections mentioned above.

In a further advantageous embodiment, the lifting device has a ground tube and a piston arranged inside this ground tube. The tightness or leaks to be checked can occur in both of the elements mentioned.

The gas supply line can in particular but not exclusively be a line. However, a simple connection would also be possible, which would allow compressed air to be fed into the sealed space. The gas discharge device that is preferably provided can be a valve device, for example. However, it would also be possible for a measuring device, which is suitable and intended for determining a pressure, to be integrated directly into the device instead of the sealing device. The measuring device can protrude into the sealed space to be checked. However, it would also be possible for this sealed space to be connected to the measuring device via a line connection. For example, the sealing device can have a connection for a gas line, which in turn can be connected to the measuring device.
In a preferred embodiment, at least two lines and preferably exactly two lines are arranged on the sealing device. In particular, these are hose lines. It is thus possible for at least one and preferably the two hose lines to be fastened in the sealing device, which is in particular designed as a sealing cushion, and in particular to be vulcanized into this sealing device. One of these lines can pass through the sealing device. This line preferably serves to pressurize the sealed space with compressed air.

These two lines preferably protrude from the sealing device by a predetermined area. This area can be both very short, for example 3 mm, and very long, around 10 m, if this line is to be connected to another unit. In addition, it would also be possible for that line or hose that is vulcanized by the sealing device in one embodiment to be introduced as an external hose in another embodiment. In this embodiment, it would be possible for the sealing device to have a feed-through device such as, in particular but not exclusively, a feed-through opening for feeding through an external line and in particular an external hose.

The sealing device is preferably designed as a sealing cushion.

In a further advantageous embodiment, the measuring device is suitable and specific for measuring a pressure permanently or over a predetermined period of time. In particular, the measuring device should be suitable and intended to also determine or measure a pressure drop.

The fluid-actuated lifting device is advantageously a hydraulic lifting platform.

In a further advantageous embodiment, the device has a gas discharge device in order to discharge a gas from the space sealed off by the sealing device. In particular, this gas can be supplied to a measuring device which determines the gas pressure. In this way, the measuring device can be designed outside of the device and the actual sealing device can be designed in a relatively simple manner.
In a further advantageous embodiment, the seal has a circumferentially formable sealing section in order to seal the circumferential gap with respect to a predetermined axis. This section can be designed to be flexible, so that it can also be easily adapted to different pipe diameters. However, this sealing section advantageously has a length which is greater than the circumference of a pipe to which this sealing section is to be applied, in particular greater than a corresponding inner pipe. What is achieved in this way is that certain sections of the sealing device overlap in the circumferential direction, so that a high degree of tightness is also ensured here.

For example, the sealing section can have a length that is more than 10% greater than the circumference of the pipe area to be checked, preferably more than 20% of the corresponding diameter. The length can also be selected in such a way that different diameters of pipes can be sealed.

As part of a corresponding method, said sealing device can first be introduced into the gap and then expanded by a flow agent, so that the space is completely sealed. The sealing device itself therefore preferably has flexible surfaces which are suitable and intended for contacting corresponding walls of the lifting device to be checked. A first surface of the sealing device can thus contact an inner wall of the lifting platform or of the Create Erdrohrs and a second opposite surface of the sealing device can create a corresponding inner pipe. In this way, a very high sealing effect is achieved overall.

In a further advantageous embodiment, the sealing device has a width which, in a mounted state, protrudes into the lifting device to be checked and/or the above-mentioned gap and which in particular also extends parallel to an axis in which the lifting effect is deployed. This width is advantageously at least 10 cm, preferably at least 20 cm and preferably at least 30 cm.

The sealing device is advantageously made of a material which is selected from a group of materials which types of rubber, such as in particular but not exclusively natural rubber (NR), styrene-butadiene rubber (SBR), isobutene-isoprene rubber (IIR), ethylene -Propylene Diene Rubber, Ethylene Propylene Rubber (EPM), Chloroprene Rubber (CR), Chlorosulfonyl Polyethylene Rubber (CSM), Nitrile Butadiene Rubber (NBR), Hydrogenated Acrylonitrile Butadiene Rubber (HNBR), Polyurethane -Caoutchouc (PUR), silicone (SI - rubber), MVQ / VMQ silicone rubber, fluorosilicone rubber (FVMQ), fluororubber (FPM/FKM), high-styrene rubber (HSR), silicone rubber (Q) and silicone rubber (SIR ) contains. Combinations and mixtures of these materials can also be used.

In addition, plastic materials can also be used which are selected from a group of materials which contains polyolefins, styrene polymers and elastomers. In addition, textiles can also be used and in particular textiles with a foil, such as in particular but not exclusively felt, glass fiber and cotton. These materials can be knitted, woven and/or needled. In addition, mixtures of these plastic materials can also be used.

In a further advantageous embodiment it is possible that at least this peripheral sealing section can be expanded by the flowable medium. The flowable medium is particularly preferably compressed air.

In a further advantageous embodiment, the sealing section can be inserted into a tubular body which forms part of the lifting device to be checked. More precisely, the sealing section can be inserted into a corresponding gap between a tubular body and a second body arranged inside this tubular body.

According to the invention, the sealing device has a cover element which is suitable and intended for covering a tubular body which forms part of the installation to be checked and in particular the lifting device. In this way, any opening in said inner tube of the lifting device can also be covered. This cover element advantageously extends in a radial direction beyond the tubular body to be checked.

Furthermore, the sealing section or sealing body is arranged on the cover element. According to the invention, the cover element and the sealing section are formed in one piece with one another. The cover element can also be a flexible body. This cover element can also be acted upon by the flowable medium and can expand as a result of being acted upon by the flowable medium. The cover element is also advantageously made of a flexible material.

In a further advantageous embodiment, at least the gas supply device and/or a gas discharge device runs at least in sections within a space surrounded by the sealing section or sealing body. It is thus possible for the gas supply device to run within a surface which is surrounded by the sealing section or sealing body. The sealing section is therefore in particular the sealing body already mentioned above.

In a further advantageous embodiment, the device has a valve device which is suitable and intended for at least temporarily preventing the gaseous medium from escaping from the sealed space. This can be a non-return valve, for example, which allows the said space to be pumped up, but not the gas to escape. In addition, however, it would also be possible for this valve to be arranged on a discharge line and to be able to be opened or closed as required. It would also be conceivable for this non-return valve to be opened when a connecting line which leads to the (gas pressure) measuring device is connected.

The present invention is further directed to a method of inspecting fluid operated elevators. In a first method step, a sealing device is placed in an area to be sealed, namely a sealing gap of the device to be checked introduced to seal a space of this device. This is a room of the lifting device.

In a further method step, pressure is applied to the space sealed by the sealing device. In a further method step, a pressure is measured in the space sealed off by the sealing device. In particular, a change in pressure in the space sealed by the sealing device is also measured.

According to the invention, a sealing body of the sealing device is expanded within the area, i.e. the gap, by application of a flowable medium in order to seal the space.

In terms of the method, it is therefore also proposed that the sealing be effected by applying a flowable medium and in particular a gaseous medium to a sealing device.

The pressure is preferably measured over a predetermined period of time. In particular, it is determined whether the pressure remains constant within specified limits. If a certain drop in pressure is detected, this can be taken as an indication of a leak occurring.

• 1 eine Darstellung einer erfindungsgemäßen Vorrichtung;
• 2 Darstellungen einer Abdichteinrichtung; und
• 3a - 3z mögliche Ausgestaltungen eines expandierbaren Körpers.

Further advantages and embodiments result from the accompanying drawings. Show in it:

• 1 a representation of a device according to the invention;
• 2 Representations of a sealing device; and
• 3a - 3z possible configurations of an expandable body.

1 shows a schematic representation of a device according to the invention for checking hydraulic lifting devices 10. Reference number 32 refers to a reservoir for a free-flowing medium, for example oil, for operating the lifting device. The reference number 34 denotes a lifting ram and the reference number 30 denotes a carrier on which an object to be lifted, such as a vehicle, can be arranged.

Numeral 2 designates in its entirety a sealing means for covering a space 10a formed between a cartridge 14 and a plunger 16. As shown in FIG. This sealing device has a flexible body 22 that can be expanded by a medium, by means of which the circumferential gap Sp formed between the cassette 14 and the piston can be sealed. The cassette 14 thus also represents the tubular body into which the expandable body can be inserted.

The reference number 24 represents a cover element which is formed together with the expandable body 22 here. This cover element is used to advantageously cover the cassette 14 completely. Reference number 4 designates a gas supply device, by means of which a gas can be supplied to the space 10a sealed off by the sealing device 2 . The reference number 6 designates a gas discharge line, by means of which gas can be discharged from the sealed space 10a and fed to a measuring device 12 . This measuring device 12 can thus measure the pressure within the sealed space 10a and, in particular, can measure this pressure over a longer period of time.

The reference number 8 designates a further gas supply line, which serves to expand the expandable body 22 . However, it would also be conceivable for this expansion to also take place by means of line 4 . Unlike in 1 shown to be fed centrally to the cover element 24 .

It would also be conceivable and preferred for the gas supply device 4 and the gas discharge line 6 to be combined in the form of a single line. It is possible that compressed air is first applied to the sealed space 10a via the gas supply line 4 and then (e.g. by switching appropriate valves) the gas supply line also serves as a gas discharge line or connection line to the measuring device 12 in order to reduce the pressure within the space 10a to be able to measure. It is pointed out here that the gas discharge device is preferably a measuring line which connects the sealed space to the measuring device 12 . This means that the gas discharge line is in particular not suitable and intended for discharging large quantities of gas from the sealed space, but rather for connecting the measuring device 12 to the sealed space 10a.

2 shows a detailed representation of the in 1 shown device. Here again the space 10a to be sealed can be seen, as well as the expandable body 22, which has been introduced into the gap Sp and has already been expanded by air pressure. The cover element can also be seen again, which is arranged here above the expandable body and also covers said gap at the top. Numerals 26 and 28 denote terminals to which respectively Air lines can be connected. Numeral 4 designates gas supply means for supplying a gas, particularly compressed air, to the sealed space 10a.

It would be possible for the compressed air to be supplied directly to space 10a, but it would also be conceivable for the compressed air to be supplied to another area of system 10 and for it to flow from this other area into space 10a and a pressure change to be detected there can. Reference number 8 designates the line section, the line, by means of which the expandable element is filled with compressed air and is thus expanded.

The 3a until 3z 12 and 14 show a variety of possible configurations of the expandable body 22. The expandable body shown in these figures can have a variety of configurations. These possible configurations are based in particular on the structure or the shape of the gap to be sealed. In all embodiments, however, the expandable body 22 is elastic and can be wrapped around a rod-shaped or tubular body to be tested. However, the expandable element preferably has a width that is large enough that the expandable body can be placed at least completely around the respective inner tube 16, but in particular the end sections of the expandable body overlap.

For example, the expandable body 22 may have a square shape ( 3a ), also with truncated corners ( 3e and 3f ) or also a rectangular shape ( 3d ) with or without rounded corners. Furthermore, the expandable body can also have a triangular ( 3c and 3g ) or pentagonal shape ( 3y and 3I ) exhibit.

Furthermore, mixed geometric shapes consisting of curved edges and straight edges can also be considered ( 3m , 3n , 3o , 3x ), or L-shaped shapes ( 3p ) or cruciform figures ( 3q ). In addition, trapezoidal configurations ( 3k , 3y ) conceivable as well as diamond-shaped configurations ( 3i , 3v ).

The applicant reserves the right to claim all features disclosed in the application documents as essential to the invention, provided they are new compared to the prior art, either individually or in combination. It is also pointed out that the individual figures also describe features which can be advantageous in and of themselves. The person skilled in the art recognizes immediately that a specific feature described in a figure can also be advantageous without adopting further features from this figure. Furthermore, the person skilled in the art recognizes that advantages can also result from a combination of several features shown in individual figures or in different figures.

Reference List

2

sealing device

4

gas supply device

6

gas evacuation line

8th

line section

10

lifting device

10a

sealed room

12

measuring device

14

cassette

16

Pistons

22

expandable sealing body

24

cover element

26, 28

connections

30

carrier

32

reservoir

34

lifting ram

Sp

gap

Claims (8)

Device for checking fluid-actuated lifting devices (10), with a sealing device (2) which is suitable and intended for sealing off a predetermined space section (10a) of the lifting device at least temporarily, with a gas supply device (4) in order to to supply a gas to the sealed space (10a) and with a measuring device (12) which is suitable and intended for determining a pressure within the space (10a) sealed by the sealing device, the sealing device (2) having a medium that can be expanded by a flowable medium Has a sealing body (22) which expands when it is acted upon by this flowable medium in such a way that a gap (Sp) in the space (10a) can be sealed in order to seal off the space (10a), and the sealing device (2) has a cover element ( 24) suitable and intended to have a tubular body forming part of the lifting device to be checked forms to cover, characterized in that the cover element (24) and the sealing body (22) are formed in one piece with one another. Device (1) after claim 1 , characterized in that the device has a gas discharge device (6) in order to discharge a gas from the space (10a) sealed off by the sealing device (2). Device (1) according to at least one of the preceding claims, characterized in that the sealing device (2) has a peripheral sealing body (22) in order to seal the peripheral gap (Sp) with respect to a predetermined axis. Device (1) after claim 3 , characterized in that at least this circumferentially formed sealing body (22) is expandable by the flowable medium. Device according to at least one of the preceding Claims 1 - 3 characterized in that the sealing body (22) is insertable into a tubular body forming part of the lifting device to be checked. Device according to at least one of the preceding claims, characterized in that at least the gas supply device (4) and/or the gas discharge device (6) run at least in sections within a space surrounded by the sealing body (22). Device according to at least one of the preceding claims, characterized in that the device has a valve device which is suitable and intended for at least temporarily preventing the gaseous medium from escaping from the sealed space (10a). A method for inspecting fluid-actuated lifting devices (10), comprising the steps of: - inserting a sealing device (2) into a gap (Sp) to be sealed of the lifting device in order to seal a space (10a) of the lifting device - applying pressure to one of the sealing devices (2) sealed space - measurement of a pressure in the space sealed by the sealing device (2), a sealing body (22) of the sealing device (2) being expanded within the gap (Sp) by exposure to a flowable medium in order to seal the space (10a). , the sealing device (2) having a cover element (24) which is suitable and intended for covering a tubular body which forms part of the lifting device to be checked, characterized in that the cover element (24) and the sealing body (22 ) are formed in one piece with each other.

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