WO2007012385A1

WO2007012385A1 - Apparatus and method for cleaning rails

Info

Publication number: WO2007012385A1
Application number: PCT/EP2006/006521
Authority: WO
Inventors: Peter Krabbendam
Original assignee: Linde Aktiengesellschaft
Priority date: 2005-07-28
Filing date: 2006-07-04
Publication date: 2007-02-01
Also published as: DE102005035433A1; EP1907305A1

Abstract

The present invention relates to an apparatus and a method for cleaning rails (1) of fully or partially automated assembly lines in industrial production plants, for example in production plants of the motor-vehicle industry.

Description

description

Device and method for cleaning rails

The present invention relates to an apparatus and a method for cleaning rails and / or conveyor chains of fully or partially automated production lines in industrial manufacturing plants, for example in manufacturing plants of the automotive industry.

In industrial manufacturing plants, manufacturing components are brought to the place where they are to be available for the manufacturing or production process. This is usually done by means of a transport system having rails along which the manufacturing components are transported. Most depend on the transportable manufacturing components on the rails, the z. B. 2 or 3 meters above the floor of a production hall horizontally. To control the path that a manufacturing component should cover, the rails usually have a control system that transmits signals for controlling the way by means of electrical contacts. The drive of the parts to be transported can also be done mechanically, for example by means of transport chains, which extend for example in the rails. During transport, the parts to be transported can remain permanently connected to the transport chain (circular conveyor systems) or can be decoupled from time to time (so-called Power & Free systems).

The rails and chains are polluting during the industrial manufacturing process. Pollution often leads to impairments during transport and production of the manufacturing components. For example, the transport slows down because the pollution increases the running resistance, or there is a misalignment of manufacturing components, because the pollution covers the electrical contacts and this leads to a faulty signal transmission. In paint or coating systems there is a risk that the dirt particles deposit on the components and cause a faulty coating by powder or varnish there. In addition, the tensile forces in the transport chains can increase significantly due to the accumulation of pollution. Object of the present invention is to provide an efficient, cost-effective and material-friendly device for cleaning rails and chains of fully or partially automated production lines in industrial manufacturing plants as well as an efficient, inexpensive and material-friendly cleaning process for it.

The object is achieved on the device side by a device comprising the following elements:

solid carbon dioxide discharging means, the solid carbon dioxide discharging means and the running rail or transporting chain being relatively movable, and

- A storage tank for the solid carbon dioxide and / or a device for the production of solid carbon dioxide and

- One or more discharge openings or nozzles for the solid carbon dioxide, and

a suction device for removing soiling dissolved during cleaning, which is arranged adjacent to the discharge opening or nozzles for the solid carbon dioxide.

As used herein, the term "cleaning" is intended to generically refer to any process in which soiling or otherwise coating or adhering to a surface is removed.

The term "transport chain" includes any type of self-propelled train systems, in addition to chains in the strict sense, for example, traction cables and the like, as well as any existing link joints, wheels or rollers or carriages.

The rails or transport chains can be arranged so that the parts to be transported are suspended suspended. The transport system with rails and possibly transport chains can also run on the ground.

In a preferred embodiment of the invention, the device for discharging the solid carbon dioxide along the running rail is designed to be movable. The device according to the invention is preferably guided along the running rail to be cleaned, wherein it is irradiated with solid carbon dioxide and cleaned. The detached dirt is sucked off with the help of a suction device. It is also possible to provide a stationary cleaning device, past which the transport chain is passed and irradiated with carbon dioxide pellets or carbon dioxide snow.

The solid carbon dioxide is preferably provided in pressed form, in particular in the form of dry ice pellets. Dry ice pellets are in the form of pellets or tablets pressed carbon dioxide snow of z. B. 5 mm - 30 mm in length and a diameter of about 3mm. Upon impact of the dry ice on the track or transport chain results from the presence of a temperature gradient between the temperature of the dry ice (-78 ⁰ C) and the temperature of the track (usually at least ambient temperature, often higher, for example, if the conveyor goes through a paint dryer) a different temperature expansion between the contamination and the surface of the running rail or transport chain, which causes a breakdown of the contamination of the running rail or transport chain.

This break-off is additionally supported by the property of the dry ice to go directly from the solid to the gaseous phase when energy is supplied (sublimation). An energy supply in the form of heat energy occurs when the dry ice strikes the much warmer track or transport chain in any case. Due to the sublimation of the dry ice on impact with the running rail or transport chain to be cleaned, the volume of the dry ice multiplies by a factor of about 500. This increase in volume favors the splitting off of the dirt from the running rail or transport chain.

Instead of dry ice pellets but it is also possible to clean the rails or transport chains with carbon dioxide snow. Especially with lighter soiling cleaning with carbon dioxide snow is preferable because then can be dispensed with the generation or provision of carbon dioxide pellets. The carbon dioxide snow can be generated by simply relaxing liquid carbon dioxide.

The cleaning of the running rail should here include the cleaning of the rail body and all connecting parts and contacts. In monorail systems should in particular, the electrical contacts of the control system, by means of which signals are transmitted for controlling the travel of the production rails to be transported on the running rail, are cleaned. In circular conveyor systems or power & free systems, the entire inner surface of the track is preferably cleaned.

The cleaning of the transport chain should include the cleaning of the chain body and all connecting parts, in particular the cleaning of the joints with rollers.

In the event that a dispensing nozzle is provided, a Laval or Venturi nozzle can be used with particular advantage in coordination with the desired beam characteristic. By using one or more nozzles, the dry ice pellets or snow particles can be easily accelerated to a desired speed. For example, with a Laval nozzle, the dry ice or carbon dioxide snow jet can be accelerated approximately to the speed of sound.

Advantageously, the device for emitting solid carbon dioxide further comprises a metering device, which is in communication with a compressed air supply line. The dry ice pellets or CO ₂ snow particles are advantageously accelerated by means of compressed air. Upon impact with the rails or chains to be cleaned so that the destruction of adhering to the rails pollution is further promoted. The metering device improves the efficiency of the device according to the invention, since the amount of solid carbon dioxide to be delivered can be adjusted to the demand, ie to the particular degree of contamination present. For example, a metering device is provided which has a rotatable perforated disc as a metering device.

According to an advantageous embodiment of the invention, a housing is provided, which is designed to be movable along the running rail and receives the means for discharging the solid carbon dioxide and the suction device. Particularly preferably, the housing is movably connected to the running rail or chain along the running rail.

Of particular advantage are the production and metering of the solid carbon dioxide, in particular of carbon dioxide pellets, take place in the compressed air stream in a common device. The cold parts of this device, that is the Parts which have direct contact with the cold carbon dioxide are preferably arranged in an insulated and inertized chamber, so that the cold parts do not come into contact with atmospheric moisture. The inertization can be carried out, for example, by means of gaseous nitrogen or, preferably, by means of gaseous carbon dioxide. It is particularly advantageous to use the carbon dioxide gas produced during the production of dry ice pellets for the inertization.

In terms of the method, the stated object is achieved by a method comprising the following steps:

I) providing solid carbon dioxide,

II) moving means for delivering the solid carbon dioxide relative to the track or transport chain, the solid carbon dioxide delivery means comprising a solid carbon dioxide storage tank and / or solid carbon dioxide generating means and one or more discharge openings or nozzles for the solid carbon dioxide,

III) emitting the solid carbon dioxide on the running rail and / or the transport chain, wherein a contamination on the running rail and / or the transport chain is solved, and

IV) removing the dissolved soil from the track rail and / or transport chain by means of a suction device disposed adjacent to the solid carbon dioxide discharge port or nozzles.

Preferably, the movement of the solid carbon dioxide delivery means along the track of the production line is controlled by means provided in the manufacturing equipment transport control equipment.

As already described above, dry ice in pressed form, in particular in the form of dry ice pellets, is particularly preferably used.

The present invention has a number of advantages: it achieves an excellent cleaning result. The removed and extracted dirt is usually present in this cleaning process as the smallest particles that require no further post-processing and can be easily removed. As further advantages can be stated that the cleaning is dry and wear-free for the surface to be cleaned. Furthermore, it is advantageous that the carbon dioxide does not mix with the removed dirt due to the sublimation, as is usually the case in wet cleaning processes. The disposal is thereby simplified and can be carried out inexpensively, whereby the cost efficiency of the cleaning process is increased.

The invention is particularly suitable for cleaning rails and transport chains or generally of transport systems in manufacturing plants of the automotive industry. But also transport systems in powder coating plants, paint shops and other fully or partially automated production lines can be cleaned according to the invention with advantage.

The invention and further embodiments of the invention are explained in more detail below with reference to the exemplary embodiments illustrated in the figures. Hereby show:

Figure 1 is a movable along a running rail according to the invention

Cleaning device

FIG. 2 shows a stationary cleaning device and FIG. 3 shows a device for producing and blasting off

Carbon dioxide pellets.

Figure 1 shows a schematic representation of the invention. In detail, FIG. 1 shows a running rail 1, on which a housing 8, which is designed to be movable along the running rail 1, hangs on a suspension 9. The housing 8 accommodates a device 2 for dispensing dry ice and a suction device 6. The device 2 for dispensing dry ice has a dry ice storage container (not shown) from which dry ice pellets are fed by means of compressed air supplied via the compressed air supply 4 to the device 2 removed and fed via the feed 5 of the dispensing nozzle 3. Optionally, a dry ice dispenser (not shown) is interposed between the dry ice storage bin and the feeder 5. From the dispensing nozzle 3 exits a dry ice jet, which is directed to the track rail 1 and there dissolves in the manner described above there existing pollution, which is then sucked off via a suction line 6 associated suction line 7.

In the event that it is in the track rail 1 is a track in a manufacturing plant in the automotive industry, the sucked pollution will contain, for example, copper dust, which preferably deposits on the electrical contacts of the track rail 1. By suction is advantageously avoided that this gets into the work environment.

As an alternative to the dry ice storage container, it is possible to use a dry ice production device which produces dry ice pellets from liquid carbon dioxide in a so-called "on-board process." Such a device is shown in FIG.

A reservoir for carbon dioxide, z. B. a tank in which the liquid carbon dioxide under a pressure of about 20 bar at - 20 ⁰ C is present, liquid carbon dioxide is removed and fed via a supply line 11 of a device 10 for producing dry ice pellets. The reservoir can also be carried along with the device 2 for delivering dry ice or not be carried along and be connected only via a flexible line with the dry ice generating device.

In the pellet production device 10, carbon dioxide snow is generated by expansion, which is then compressed and processed in a known manner to form carbon dioxide pellets. The dry ice generating device 10 may, for example, be designed as a "nozzle baffle plate system" or operate according to another known method for producing dry ice from liquid carbon dioxide.

The pellets produced are ejected via an outlet opening 12 from the dry ice generating device 10 and collected in a reservoir 13. At the lower end of the funnel-shaped storage container 13 is a metering device 14, in which the carbon dioxide pellets are metered from the reservoir 13 in a compressed air stream 15. The compressed air Dry ice stream is fed via line 16 one or more radiating nozzles and blasted onto the rails or transport chains to be cleaned.

The storage container 13 and the metering device 14 are located in an insulated space 17, in which the outlet opening 12 of the dry ice generating device 10 protrudes. Furthermore, a CO _Σ exhaust gas line 18, through which the gaseous carbon dioxide formed during pellet production in the dry ice generating device 10 can be conducted into the space 17, opens into the space 17. For safety reasons, the isolated space 17 is provided with a pressure relief valve 19. The supplied via line 18, gaseous carbon dioxide displaces the ambient air, in particular moisture, from the isolated space 17, so that icing can be avoided. The complete system of dry ice generating device 10, reservoir 13 and metering device 14 is housed in a common housing 20.

FIG. 3 shows a stationary embodiment of the invention for cleaning transport chains 21 of a conveyor system. The transport chain 21 has a plurality of joints 22 and rollers 23 which run in rails 24, 25. Between two rails 24, 25, the cleaning device is arranged. In the embodiment shown, four jet nozzles 26 are provided, via which carbon dioxide pellets can be radiated with compressed air. The jet nozzles 26 are preferably connected to a pellet production device according to FIG. The jet nozzles 26 radiate from all sides onto the conveyor chain 21, so that they are detected and cleaned by the carbon dioxide pellet jet on their entire circumference, and in particular also the connecting joints 22 and the rollers 23. The detached impurities are preferably sucked off by means of a suction device 27.

Claims

claims

Device for cleaning runners (1) and / or transport chains (21) of fully or partially automated production lines in industrial manufacturing plants, for example in manufacturing plants of the motor vehicle industry, comprising the following elements:

- A device (2) for the release of solid carbon dioxide, wherein the means for delivering the solid carbon dioxide and the running rail (1) or the transport chain (21) are movable relative to each other, and

- A reservoir (13) for the solid carbon dioxide and / or means (10) for generating solid carbon dioxide and

- One or more discharge openings or nozzles (3, 26) for the solid carbon dioxide, and

- A suction device (6, 27) for the extraction of dissolved in cleaning pollution disposed adjacent to the discharge openings or nozzles (3, 26) for the solid carbon dioxide.

2. Apparatus according to claim 1, characterized in that the means (2) for discharging the solid carbon dioxide and the suction device (6) along the running rail (1) are designed to be movable.

3. Device according to one of claims 1 or 2, characterized in that the means (2) for delivering des.festen carbon dioxide furthermore a metering device (14) which communicates with a compressed air supply line (4, 15).

4. Device according to one of claims 2 or 3, characterized in that a housing (8) is provided, which is formed along the running rail (1) movable and the means (2) for discharging the solid carbon dioxide and the suction device (6). receives.

5. Apparatus according to claim 4, characterized in that the housing (8) along the running rail (1) is movably connected to the running rail (1) or the transport chain.

6. Device according to one of claims 1 to 5, characterized in that the means (10) for generating the solid carbon dioxide and the means (2, 13, 14) for discharging the solid carbon dioxide in a common housing (20) are housed.

7. A method for cleaning rails (1) and / or transport chains (21) of fully or partially automated production lines in industrial manufacturing plants, for example in manufacturing plants of the automotive industry, comprising the following steps:

I) providing solid carbon dioxide,

II) moving a device (2) for emitting the solid carbon dioxide relative to the track rail (1) or the transport chain (21), wherein the means (2) for delivering the solid carbon dioxide, a reservoir (13) for the solid carbon dioxide and / or a device (10) for generating solid carbon dioxide and one or more discharge openings or nozzles (3, 26) for the solid carbon dioxide,

III) emitting the solid carbon dioxide on the running rail (1) and / or the transport chain (21), wherein contamination on the running rail (1) and / or the transport chain (21) is released, and

IV) Removing the dissolved contamination from the running rail (1) and / or the transport chain (21) by means of a suction device (6, 27), which is adjacent to the or the discharge openings or nozzles (3, 26) for the solid carbon dioxide ,

8. The method according to claim 7, characterized in that the means (2) for discharging the solid carbon dioxide along the running rail (1) and / or the transport chain is moved.

9. The method according to claim 8, characterized in that the movement of the device (2) for discharging the solid carbon dioxide along the running rail (1) of the production line is controlled by an existing in the manufacturing equipment for controlling the transport of manufacturing components.

10. The method according to any one of claims 7 to 9, characterized in that solid carbon dioxide in compressed form, in particular in the form of dry ice pellets, is used.