DEVICE AND ARRANGEMENT FOR FILLING PROCESSING STATIONS

Abstract

A device for filling processing stations (16) with a pumpable working material guarantees a permanent and sufficient supply of working material to the processing station with the lowest possible expense and greatest possible cleanliness. The device includes a transfer chamber (42) assigned to a central tank (55) for the working material. The transfer chamber (42) is assigned to a processing station (16), in such a way that the working material can be fed at first from the central tank (55) into the transfer chamber (42) and from there to the processing station (16). An arrangement is also provided that includes such a device.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. §119 of European Patent Application EP 10 160 122.7 filed Apr. 16, 2011, the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention pertains to a device for filling processing stations with a pumpable working material (operating substance). The present invention pertains, furthermore, to an arrangement for filling processing stations with a pumpable working material, with a central tank for the working material and with two or more processing stations and a feed line for feeding the working material to one of the processing stations.

BACKGROUND OF THE INVENTION

Even though the present invention is suitable for all pumpable working materials, i.e., bulk materials, gel-like or pasty substances or liquids, a concrete application of the present invention is the preparation of hot-melt adhesives for a heat-sealing means, for example, in packaging machines. The heat-sealing means is thus a processing station in this case. The hot-melt adhesive is provided as bulk material, especially in the form of granular material, also designated as pellets, and is usually stored in tanks directly at the heat-sealing means. Each heat-sealing means has its own tank with a corresponding capacity, into which the granular material is filled. The drawback in this case is that the environment of the tank is very hot, such that the personnel may be burned while filling the tank. Moreover, in the case of high-performance heat-sealing means, the tank has to be refilled very frequently, which requires a corresponding workforce. There is also the risk that sufficient granular material is not present in the tank, which may lead to defects in the bond and to production rejects as well as to production losses. Furthermore, it occurs that granular material is spilled during the refilling of the tank and the environment becomes contaminated with it. It should be taken into consideration here that spilled material is always also mixed with dust because of abrasion, which contaminates the environment as well. Moreover, spilled granular material may come into contact with hot parts of the heat-sealing means and then melt. The heat-sealing means is further contaminated as a result of this. This is always undesirable. Contaminations are especially of special concern in packaging machines for food.

To avoid these drawbacks, in practice the granular material was already prepared in drums and the tank of the heat-sealing means was refilled from the drum via a corresponding refill line. Exactly one tank is assigned to each drum in this case. The workforce is reduced here, since the drum has a greater capacity than the tank. However, the personnel must still always monitor that the drums are replaced in a timely manner. Moreover, the conveying track, via which the granular material is conveyed, is highly limited in this variant, such that drums have to be set up close to the respective heat-sealing means. These drum locations are often not easily accessible sites. Moreover, it has been shown in practice that the granular material easily becomes lumpy in the drums.

SUMMARY OF THE INVENTION

The arrangement according to the present invention includes a device with a transfer chamber that is assigned to a central tank for the working material. the transfer tank of the invention may be provided in a combination with features according to DE 20 2009 005 561 U1 which is hereby incorporated by reference in its entirety. The transfer chamber is assigned to the processing station, in such a way that the working material can be conveyed at first from the central tank into the transfer chamber and from there to the processing station.

By the working material at first transferring from the central tank to a transfer chamber, i.e., a preportioning of the working material is performed so to speak, greater conveying paths can also be accommodated. For this reason, the central tank may be arranged at an easily accessible site as well, such that it can be refilled in a simple manner. Therefore and because of a greater capacity, the central tank can be refilled almost free from contaminations and arranged at a distance from the processing stations, i.e., mainly the heat-sealing stations, such that the risk of injury, especially the risk of getting burned, is avoided. Contaminations that may still possibly occur involve contaminants that pass at a distance from the processing station and can be easily removed. In this case exactly one processing station may be present that is supplied from the central tank. However, the present invention is mainly intended for supplying a plurality of the processing stations, including a heat-sealing means according to the above example, from a common central tank with the working material, granular material of the hot-melt adhesive. In this way, only one more central tank needs to be monitored, as a result of which the operating cost is considerably reduced.

An object of the present invention is to provide an effective transfer chamber for an arrangement for supplying processing stations with pumpable substances, and especially for processing stations according to DE 20 2009 005 561 U1.

For this purpose, a bottom surface deepening towards a sump in a funnel-like manner is provided at the bottom of the transfer chamber. The sump may be provided in the center in the bottom of the transfer chamber, but also off-center, for example, laterally. The sump should be embodied as a blind hole and have a diameter that corresponds approximately to the internal diameter of the discharge opening or of the feed tube. Also, as a result of this, the working material can be easily blown out of the transfer chamber. Conveying tracks (paths) of about 100 m and a height difference of up to 25 m can be overcome with such an equipped pilot plant. This alternative embodiment of the transfer chamber is also conceivable independent of the device and arrangement according to the present invention.

The transfer chamber can be closed upwards towards the central tank by means of a ball valve. As a closing means, such ball valves have a ball provided with a passage hole. If this ball is brought into its closed position, the granular material remains behind in the passage hole, which then becomes lumpy already at room temperature and consequently clogs the passage hole even in the open position. To avoid this, provisions are made according to a variant that the closing means is also open towards the transfer chamber even in the closed position. As a result of this, granular material remaining behind in the closing means can always flow out into the transfer chamber and thus not clog the closing means.

According to the arrangement according to the present invention, two or more transfer chambers may be assigned to the central tank, whereby a processing station is respectively assigned to each transfer chamber. This may result in that a particular line for the working material is always guided to a particular processing station from each of the transfer chambers. Thus, there is a star-shaped connection of the processing stations to the central tank. However, it is also conceivable that the central tank is provided with only one transfer chamber, to which two or more processing stations are then assigned. In this case, the transfer chamber is connected to a concrete processing station by means of switches in the line, respectively, such that only one concrete line is always switched between the transfer chamber and the respective processing station. This variant may be designated as a tree structure, in which, starting from the transfer chamber the trunk, a plurality of branchings arise. Of course, in the tree structure it is also possible to assign two or more transfer chambers to the central tank, such that an own tree structure then starts from each transfer chamber. It is also conceivable to provide transverse connections under the individual tree structures, such that, as an option, two processing stations arranged within the one tree structure may also at the same time be supplied with working material, if this should be necessary. As already indicated above, it is important only that at each point in time only one entirely particular path from one of the transfer chambers is always switched to an entirely defined processing station for the working material. In the simplest case, this can be embodied by a ring line that starts from a transfer chamber and ends in another transfer chamber. Then, a line from the processing station to be filled is always switched to the transfer chamber placed next to it—once around to the right and once around to the left, such that two processing stations can always be filled at the same time.

According to a variant of the arrangement according to the present invention, provisions are made that the working material is fed from the transfer chamber at first to a means for separating the pressurizing means, i.e., for example, compressed air, and is conveyed from there in an unpressurized manner into the tank of the processing station. In the prior-art process mentioned in the introduction, in which the granular material of the hot-melt adhesive was conveyed from the drum by means of compressed air into the tank of the processing station, this also led to a cooling of the heat-sealing means. As a result of this, the heat-sealing means was partly cooled below the melting point of the hot-melt adhesive, which led to disturbances in the operating sequence. Since, according to the present variant, the compressed air is already separated beforehand and the working material flows into the tank in an unpressurized manner, this risk is avoided.

The present invention is explained in detail below based on an exemplary embodiment shown in the drawing. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a schematic lateral view showing an adhesive supply according to DE 20 2009 005 561 U1;

FIG. 2 is a top view showing a transfer chamber with the features of the present invention;

FIG. 3 is a vertical sectional view showing the transfer chamber according to FIG. 2 taken in plane XI-XI;

FIG. 4 is a bottom view showing a transfer chamber with the transfer chamber being according to FIG. 2;

FIG. 5 is a schematic lateral view showing another exemplary embodiment with a transfer chamber according to FIG. 2 for an arrangement with the features of the present invention;

FIG. 6 is a perspective view showing a ventilating means for the arrangement according to FIG. 5; and

FIG. 7 is a perspective top view showing a cover for a working material tank of a processing station.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings in particular, the arrangement shown in FIG. 1 includes a central tank 10 with transfer cartridges 11 arranged under the central tank. Central tank 10 is mounted on columns 12 by means of vibration dampers 13 on a basic frame 14. Furthermore, a control box 15 for controlling the device is assigned to the central tank 10.

FIG. 1 shows, as representative of a random number of processing stations, a processing station, in particular a heat-sealing means 16. A working material, a granular material of a hot-melt adhesive in the present case, is fed by means of a feed line 17 at first to a ventilating means 18, the significance of which will still be explained further below. This ventilating means 18 is located above the heat-sealing means 16, specifically above a tank of same, so that the working material can flow in an unpressurized manner from the ventilating means 18 into the tank of the heat-sealing means 16. The feed line 17 is connected to the transfer cartridge 11 via a feed tube 28.

FIGS. 2 and 3 show a transfer chamber 42 according to the invention, which replaces the transfer cartridge 11 in the arrangement according to FIG. 1. This transfer chamber 42 is embodied as a cylindrical, specifically a circular cylindrical, hollow body. The transfer chamber 42 has a bottom 43, which forms a bottom surface 44, which deepens towards the center in a funnel-like manner and then passes over into a central sump 45, embodied as a blind hole in the present case. The transfer chamber 42 is closed by a cover 46, which has a screw socket 47, at the top, i.e., at an end opposite the bottom 43. In the present case, the screw socket 47 is provided with a male thread 48 on its outside, but may, in addition or as an alternative, also be embodied with a nut on its inside. Furthermore, screw socket 47 has a passage hole 49, which communicates with the internal cavity of the transfer chamber 42.

A ball valve 50, which has for this purpose a nut 51 communicating with the male thread 48 of the screw socket 47, is screwed onto the screw socket 47. If the screw socket 47 should have a female thread, the ball valve 50 is, of course, provided with a corresponding male thread. All other prior-art connecting techniques, for example, a bayonet catch between the transfer chamber 41 and ball valve 50, are also possible. Otherwise, the ball valve is embodied in the commercially available manner and is actuated via a motor actuation means 52.

At the bottom 43 of the transfer chamber 42 is arranged a discharge tube 53, which communicates with a pressurizing means in the form of a compressed air nozzle 54, with pressurized air source, which is arranged in the sump 45 of the bottom 43. The compressed air nozzle 54 may be designed as a venturi nozzle and protrudes with its opening up to into the discharge tube 53. The end 59 visible in FIG. 2 within the sump 45 bends and extends downwards and communicates with a compressed air connection. The diameter of the sump 45 is approximately and preferably exactly as large as the internal diameter of the discharge tube 53.

FIG. 4 shows a bottom view of a central tank 55, which is equipped with the transfer chambers 42. In the bottom 58 of the central tank 55 there is provided a number of openings 57, to which the transfer chambers 42 can be connected via the ball valves 50. Furthermore, a vibrating means 60, with which this central tank 55 is also equipped.

In the variant according to FIGS. 2 to 4 as well, the transfer chamber 42 is filled with a volume of the granular material, which corresponds to the volume that can be accommodated by the tank of the heat-sealing station 16. For this purpose, the ball valve 50 is opened in a time-controlled manner or via corresponding filling level sensors in the transfer chamber 42, until the respective filling level in the transfer chamber 42 is reached and the ball valve 50 is then closed again. Now, a pressurizing means is sent to the compressed air nozzle 54. The duration of the pressure surge is again measured in a time-controlled manner, so that the transfer chamber 42 is completely emptied and the granular material is fed to the tank of the heat-sealing station 16. Due to the pressure surge the granular material, as described above based on the transfer chambers 42, is conveyed from the transfer chamber 42. In this case, the flow in the transfer chamber 42 is facilitated (the material breaks down) because of the special shape of the bottom 43 in the transfer chamber 42, so that the granular material is accelerated at a high speed. In a pilot arrangement equipped with this transfer chamber 42, the granular material could be conveyed a distance of approximately 100 m, and a height difference of 25 m could be overcome.

Ordinary ball valves have a ball provided with a passage hole as closing means. It has been shown that granular material may remain behind (in the valve) when the ball valve is closed. Therefore, in the present case, the ball valve 50 is provided with a ball, which is provided with an opening, which is open towards the transfer chamber 42 even in the closed position of the ball valve, such that the granular material can always flow from the ball into the transfer chamber 42. For this, the ball can be provided with a corresponding groove or be embodied as a shell.

The device according to the present invention and arrangement according to the present invention were described above based on the example of supplying heat-sealing means with heat-sealing granular material, i.e., a bulk material. However, the present invention is suitable for all pumpable working materials, i.e., not only for bulk materials, but also for gel-like or pasty substances and liquids. The device according to the present invention and arrangement according to the present invention are also suitable for any other type of processing stations as heat-sealing means.

Furthermore, according to the above exemplary embodiments, exactly one transfer chamber 42 is always assigned to each processing station (heat-sealing station 16). As an alternative, it is also possible to assign two or more transfer chambers 42 to a processing station 16. This may be sensible in very fast running processing stations 16 with only a small tank, since then the tank is refilled from one of the transfer chambers 42 from the central tank 10. In this case, an own (dedicated) or a common ventilating means 18 may also be assigned to each transfer chamber 42 depending on the needs. It is also possible that two or more processing stations 16 are assigned to a transfer chamber 42, which are then assigned by means of switches to the transfer chamber 42. It is important only that only one processing station 16 is always presently assigned to the transfer chamber 42. Such an arrangement is shown in FIG. 5, which is based on the central tank 55 according to FIG. 4 and has the transfer chamber 42 from FIGS. 2 and 3 as a transfer chamber. Specifically, two transfer chambers 42 are shown. Of course, the central tank 55 may also be provided with only one transfer chamber 42 or even three or more transfer chambers 42.

At first a main pipeline 61, which branches into two main branches 63 and 64 at a first switch 62, starts from the transfer chamber 42. The switch 62 is, like all other switches still to be described further below as well, embodied as a three-two-way ball valve. That is, a total of three lines are assigned to the ball valve, whereby in the present case one inflow and two outflows are provided, respectively, and in particular in the case of switch 62 the main pipeline as inflow and the main branches 63 and 64 as outflow.

The main branch 63 ends at another switch 65.1, from which a branch line 66.1 branches off at an outflow. This in turn opens out in a switch 65.2, one outflow of which ends at a branch line 66.2. This goes on with a selectable number n of switches. In a similar manner, the second and possibly another other main branch 64 opens out into a first switch 67.1, leads from the one first branch line 68.1 to another switch 67.2 and so forth until a selected number of m switches 67 is reached in this case as well. The respective other outflows of the switches 65 and 67 open out in a ventilating means 69, by means of which the compressed air used for transporting the working material from the transfer 62 is removed. For this purpose, the ventilating means 69 has a tube-like, cylindrical filter 70, whose jacket surface is made of a filter material, a screen in the simplest case. The mesh size of the screen is such that the working material cannot pass through the screen, but the air transporting the working material can. A funnel-like tapered section 71, which opens out into a down pipe 72, is provided under the screen 70. The internal diameter of the down pipe 72 is smaller than the internal diameter of the filter 70 because of the tapered section 71. As a result of this, the working material is easily retained in the area of tapered section 71, is thus slowed down in its speed, without leading to a complete clogging. Because of the easy retaining of the working material in the area of the tapered section 71, the compressed air escapes through the filter 70 and the working material flows in an unpressurized manner to the processing station 16.

The tanks of the processing stations 16 are usually closed with a cover. In the case of heat-sealing machines, the cover is even insulated in order to minimize the escape of heat that is used to melt the hot-melt adhesive in the tank. Also within the framework of the present invention, the tank should therefore be closed with a cover, as this is shown schematically by the cover 73 in FIG. 5. The cover 73 itself is shown in detail in FIG. 7. The cover 73 has an opening (not visible in FIG. 7), through which the working material can flow. This opening is closed by a cap 74, which in the present case is mounted pivotably about an axis 75 at the cover 73. Another ventilating means 76, which likewise has a cylindrical filter 77 as a jacket, similar to the ventilating means 69, is arranged at the cap 74. The down pipe 72 is connected to this ventilating means 76 at the top. With the cap 74 open, the ventilating means 76 is in alignment with the opening in the cover 73, such that the working material can flow through the opening. As soon as the tank is filled, the cap 74 is pivoted into the closed position under elastic deformation of the down pipe 72. The cap 74 now closes the opening in the cover 73.

However, vapors may escape from the tank of the processing station even with the cap 74 closed. To this end, a collecting means 78, in which vapors are collected and are disposed of, for example, once daily by cleaning the collecting means 78, is assigned to the cap 74 in its closed position. As an alternative, an insulating plug may possibly also be provided here, which is charged into the opening in cover 73 with cover 73 insulated from the underside and thus provides for a continuous insulation as much as possible without heat bridges.

The cap 74 is actuated by a pneumatic cylinder 79 in a manner known per se. It is understood that the main branches 63 and 64 must not themselves be connected directly via the switches 65 and 67, respectively, to processing stations 16, but can themselves branch off into other forearms. Also, only a single main branch may be provided, which then connects directly to the transfer chamber 42. Furthermore, it is, of course, also conceivable to mix the different concepts of the arrangement according to FIG. 1 and FIG. 7 with one another and to assign them to the same central tank.

While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

APPENDIX
List of Reference Numbers
	10	Central tank	56	Bottom
	11	Transfer cartridges	57	Opening
	12	Column	58	Bottom
	13	Vibration damper	59	End
	14	Basic frame	60	Vibrating means
	15	Control box	61	Main pipeline
	16	Heat-sealing means	62	Switch
	17	Feed line	63	Main branch
	18	Ventilating means	64	Main branch
	28	Feed tube	65	Switch
	42	Transfer chamber	66	Branch line
	43	Bottom	67	Switch
	44	Bottom surface	68	Branch line
	45	Sump	69	Ventilating means
	46	Cover	70	Filter
	47	Screw socket	71	Tapered section
	48	Male thread	72	Down pipe
	49	Passage hole	73	Cover
	50	Ball valve	74	Cap
	51	Female thread	75	Hinge
	52	Actuating device	76	Ventilating means
	53	Compressed air connection	77	Filter
	54	Compressed air nozzle	78	Collecting means
	55	Central tank	79	Pneumatic cylinder

Claims

1. A device for filling processing stations with a pourable working material from a central tank for the working material, the device comprising: a transfer chamber associated with the central tank, said transfer chamber being operatively connected to a processing station such that the working material is first conveyed from the central tank into said transfer chamber and from said transfer chamber to the processing station, said transfer chamber having a bottom with a sump and with a bottom surface deepening in the manner of a funnel towards said sump.

2. A device in accordance with claim 1, wherein said sump comprises a blind hole leading to a discharge opening, said blind hole having a dimension corresponding approximately to an internal diameter of said discharge opening.

3. A device in accordance with claim 1, further comprising a pressurizing means with a pressurizing nozzle or a venturi nozzle directed towards said discharge opening, said nozzle pressurizing means being arranged in said transfer chamber.

4. A device in accordance with claim 2, further comprising a pressurizing means with a pressurizing nozzle or a venturi nozzle directed towards said discharge opening, said pressurizing means being arranged in said transfer chamber.

5. A device in accordance with claim 1, further comprising a ball valve for closing the transfer chamber with respect to the central tank, said ball valve having a closing means that is open towards said transfer chamber even in a closed position.

6. A device in accordance with claim 2, further comprising a ball valve for closing the transfer chamber with respect to the central tank, said ball valve having a closing means that is open towards said transfer chamber even in a closed position.

7. A device in accordance with claim 3, further comprising a ball valve for closing the transfer chamber with respect to the central tank, said ball valve having a closing means that is open towards said transfer chamber even in a closed position.

8. An arrangement for filling processing stations with a pumpable working material, the arrangement comprising: a central tank for the working material;a plurality of processing stations each with a tank;a plurality of feed lines, each of the feed lines being associated with one of said processing stations for feeding the working material to said one of said processing stations; anda device for filling said processing stations, the device comprising a transfer chamber associated with said central tank, said transfer chamber being operatively connected to at least one of said processing stations such that the working material is first conveyed from said central tank into said transfer chamber and from said transfer chamber to said at least one of said processing stations, said transfer chamber having a bottom with a sump and with a bottom surface deepening in the manner of a funnel towards said sump whereby the working material is conveyed from the transfer chamber at first into a pressure separation means for pressure reduction and from said pressure separation means into said tank of said at least one of said processing stations in an unpressurized manner.

9. An arrangement in accordance claim 8, wherein said device for filling said processing stations includes at least another transfer chamber to provide two or more transfer chambers associated with said central tank, whereby one of each of said plurality of processing stations is respectively assigned to one of said transfer chambers.

10. An arrangement in accordance with claim 8, wherein two or more of said processing stations are assigned to said transfer chamber, whereby said transfer chamber is always connected to one of said processing station by means of one or more switches.

11. An arrangement in accordance with claim 8, wherein said sump comprises a blind hole leading to a discharge opening, said blind hole having a dimension corresponding approximately to an internal diameter of said discharge opening.

12. An arrangement in accordance with claim 8, wherein said device for filling said processing stations further comprises a pressurizing means with a pressurizing nozzle or a venturi nozzle directed towards said discharge opening, said pressurizing means being arranged in said transfer chamber.

13. An arrangement in accordance with claim 8, wherein said device for filling said processing stations further comprises a ball valve for closing the transfer chamber with respect to said central tank, said ball valve having a closing means that is open towards said transfer chamber even in a closed position.

14. An arrangement for filling processing stations with a flowable working material, the arrangement comprising: a processing station with a processing station tank;a central tank for the working material;a device for filling said processing station, the device comprising a transfer chamber connected with said central tank; anda feed line arrangement between said transfer chamber and said processing station, said transfer chamber being operatively connected to said processing station via said feed line arrangement whereby the working material is first conveyed from said central tank into said transfer chamber and subsequently conveyed from said transfer chamber to said processing station, said transfer chamber having a bottom with a sump and with a bottom funnel surface funneling working material towards said sump.

15. An arrangement for filling processing stations according to claim 14, further comprising pressurized fluid separation means, wherein: said device for filling said processing station further comprises pressurizing means for pressurized fluid transfer of the working material from said transfer chamber through at least a portion of the feed line arrangement toward said processing station; andthe working material is conveyed from the transfer chamber at first into said pressurized fluid separation means for pressure reduction and from said pressurized fluid separation means into said processing station tank in an unpressurized manner.

16. An arrangement for filling processing stations according to claim 15, further comprising another processing station with a processing station tank to provide a plurality of processing stations, wherein: said feed line arrangement comprises a plurality of feed lines associated with said processing stations for feeding the working material to said processing stations from said transfer chamber.

17. An arrangement in accordance claim 16, wherein said device for filling said processing stations includes at least another transfer chamber to provide two or more transfer chambers associated with said central tank, whereby one of each of said plurality of processing stations is respectively assigned to an associated one of said transfer chambers.

18. An arrangement in accordance with claim 16, wherein two or more of said processing stations are assigned to said transfer chamber, whereby said transfer chamber is always connected to one of said processing station by means of one or more switches associated with said feed line arrangement.

19. An arrangement in accordance with claim 15, wherein: said sump comprises a blind hole leading to a discharge opening, said blind hole having a dimension corresponding approximately to an internal diameter of said discharge opening; andsaid pressurizing means comprises a pressurized nozzle or a venturi nozzle connected to a pressurized fluid source and directed towards said discharge opening, said pressurized nozzle or said venturi nozzle being arranged in said transfer chamber.

20. An arrangement in accordance with claim 14, wherein said device for filling said processing stations further comprises a ball valve for closing the transfer chamber with respect to said central tank, said ball valve having a closing means that allows the working material in said ball valve to flow to said transfer chamber even in a closed position of said ball valve.