DEVICE FOR CONTINUOUS HEATING OF MATERIAL

Abstract

The invention relates to a device for continuous heating of materials made of essentially nonmetallic material, comprising a continuous furnace (1) for continuous heating of material (3) on an endless circulating transportation belt (10), wherein the continuous furnace (1) has a plurality of magnetrons (4) for generating electromagnetic waves and waveguides (5) having outlet openings (6) for feeding the waves into a radiation chamber (14), and wherein the outlet openings (6) of the waveguides (5) have a main axis. The invention is distinguished in that, in the case of at least two outlet openings (6), which are arranged as closest neighbors in and/or transversely in relation to the production direction (15), the main axes (23) of the outlet openings (6) enclose an angle greater than 0 and/or the connecting line (25) of the focal points (24) of the areas of the outlet openings (6) enclose an angle greater than 0 on the perpendicular in relation to the production direction (15).

Claims

1. A device for continuous heating of materials made of essentially nonmetallic material, comprising a continuous furnace configured for continuous heating of material on an endless circulating transportation belt, the continuous furnace comprising a plurality of magnetrons configured for generating electromagnetic waves and waveguides having outlet openings configured for feeding the waves into a radiation chamber, wherein the outlet openings of the waveguides have a main axis, and wherein in a case of at least two outlet openings, which are arranged as closest neighbors in and/or transversely in relation to a production direction, main axes of the outlet openings enclose an angle greater than 0 and/or a connecting line of focal points of areas of the outlet openings enclose an angle greater than 0 on a perpendicular in relation to the production direction.

2. The device according to claim 1, wherein the angle between the main axes of the outlet openings is less than or equal to 180.

3. The device according to claim 1, wherein the angle between the connecting line of the focal points of the areas of the outlet openings on the perpendicular in relation to the production direction is less than 90.

4. The device according to claim 1, wherein the main axes of the outlet openings are perpendicular to one another.

5. The device according to claim 1, further comprising a press connected downstream in the production direction.

6. The device according to claim 1, wherein the device is configured for continuous production of materials.

7. The device according to claim 1, further comprising a control or regulating device configured for controlling individual or grouped magnetrons, to operate them using different powers to prepare a differentiated power profile, in and/or transversely in relation to the production direction.

8. The device according to claim 1, wherein the outlet openings of the waveguides are arranged in one or more planes parallel or at an angle in relation to a plane of the transportation belt.

9. The device according to claim 1, wherein the waveguides comprise round, square, rectangular, and/or oval waveguides.

10. The device according to claim 1, wherein the outlet openings are arranged in rows and columns longitudinally and transversely in relation to the production direction.

11. The device according to claim 1, further comprising a control or regulating device configured to, proceeding from the material and/or a product to be produced, retrieve predefined power profiles and set them in the continuous furnace.

12. The device according to claim 1, wherein the magnetrons have different powers.

13. The device according to claim 1, wherein the magnetrons have a power of 0.5 to 20 kW.

14. The device according to claim 1, wherein a passive and/or active distribution means for the electromagnetic waves is arranged in the radiation chamber.

15. The device according to claim 1, wherein the outlet openings are configured to be rotated manually or via a control or regulating device.

16. The device according to claim 1, wherein the angle between the main axes of the outlet openings is less than or equal to 90.

17. The device according to claim 1, wherein the device is configured for continuous production of material slabs.

18. The device according to claim 13, wherein the magnetrons have a power up to 6 kW.

Description

IN THE DRAWINGS:

[0031] FIG. 1 shows a schematic side view (top) and an associated schematic top view (bottom) of a device having a strand made of material, which is guided in the production direction through a continuous furnace and a double belt press,

[0032] FIG. 2 shows a top view of the cover of the radiation chamber of the continuous furnace having an exemplary arrangement of the waveguides,

[0033] FIG. 3 shows a section X3 in the production direction according to FIG. 2 through the radiation chamber and

[0034] FIG. 1 shows a schematic side view at the top and an associated schematic top view at the bottom of a device having two endlessly revolving steel belts, which pull the strand-shaped material 3 through the press 2, in the production direction 15 through a continuous furnace 1 and a continuously operating press 2. The material 3 is transported in this case on a transportation belt 10 from the left through the continuous furnace 1, heated therein in a radiation chamber 14, transferred to the press 2 and compressed and cured therein to form a product 8.

[0035] Depending on the embodiment of the device, for a higher efficiency, a radiation chamber 14 can be arranged not only from one upper or lower flat side, but rather a radiation chamber 14 can also apply microwaves to the material 3 from the other flat side. This can be necessary in particular if, because of a lack of penetration depth of the microwaves from one side, the material 3 cannot be heated through sufficiently or if the power for heating is to be increased. The continuous furnace 1 also has, around the radiation chamber 14, in addition to a shielding housing 11, absorbers 12, which absorb excess microwaves on the inlet and outlet sides and in addition to the airlocks, which are only indicated therein, prevent the exit of microwaves from the continuous furnace 1. The airlocks and/or the absorbers 12 are embodied as adjustable in height and/or width for adaptation to various heights and widths of the material 3 passing through.

[0036] The device can have a control or regulating device 17, which is capable of controlling the power of the plurality of magnetrons 4 for producing microwaves. In particular, the control or regulating device 17 can control magnetrons 4 individually or in groups. The control or regulating device 17 is preferably operationally connected to a memory device and/or a computer unit, which already contains formulas or predefined frame data for setting the continuous furnace 1 or the magnetrons 4, respectively. In particular, computation principles can be stored here, on the basis of which the control or regulating device 17, in conjunction with inputs of the operator with respect to the type of the material 3 and/or the product 8 to be produced, implements proposals or settings, using which the continuous furnace 1, in conjunction with the downstream press 2, can operate in a range which is optimum and harmless to the material 3.

[0037] In an alternative or combined embodiment, in the production direction 15, measuring devices 16 can be arranged before the continuous furnace 1, and measuring devices 18 can be arranged after the continuous furnace 1 and before the press 2 for the material 3. Alternatively or in combination, a measuring device 20 for the product 8 can be arranged at the outlet of the press 2. All of these mentioned or possibly further measuring devices share the feature that they are operationally connected to the control or regulating device 17 and can transmit their measurement results thereto. These measurements are the foundation for control or regulating algorithms and cause the generation and transmission in the control or regulating device 17 of corresponding commands to the continuous furnace 1 or the magnetrons 4 arranged therein, respectively.

[0038] Alternatively or in combination, further prior devices of the production facility or the control center of the facility, respectively, can be operationally connected to the control or regulating device 17 to transmit data.

[0039] These measuring devices 16, 18, 20 can preferably be capable of performing measurements over sections of the width 19 of the material 3 or the product 8, respectively.

[0040] As can furthermore be inferred from FIG. 1, the material 3 is applied to the transportation belt 10 in a height which is small in relation to the width 19. The material 3 is preferably compressed in this width 19 in the following press 2 to form the product 8. The material 3 is therefore preferably strand-shaped, has an upper and a lower flat side in this case, wherein one flat side rests on the transportation belt 10 and forms two edges 7.

[0041] FIG. 2 shows a top view in the production direction 15 from bottom to top of the cover 22 of the radiation chamber 14 in a section X2-X2 from FIG. 3. FIG. 3 shows the corresponding view of a section X3-X3 through the radiation chamber 14 according to FIG. 2, wherein the production direction 15 is oriented in the plane of the drawing.

[0042] In the combined consideration of the two FIGS. 2 and 3, the following embodiment of the radiation chamber 14 results. The magnetrons 4 are preferably arranged separately in a cabinet 13 and for better accessibility, in particular for maintenance or replacement purposes, laterally to the radiation chamber 14. The cabinet 13 has passages, through which the waveguides 5 connected to the magnetrons 4 conduct the microwaves to the radiation chamber 14 and introduce them via the outlet openings 6, corresponding to openings in the cover 22, into the radiation chamber 14. It is recognizable in the top view that the outlet openings 6 are arranged in multiple rows R (R.sub.n, R.sub.n+1) transversely in relation to the production direction 15 and columns S (S.sub.n, S.sub.n+1) longitudinally in relation to the production direction 15.

[0043] The manner of the arrangement of the outlet openings 6 on the radiation chamber 14 is dependent on the use of the continuous furnace 1, the frequency of the microwave radiation, which has an influence on the size of the waveguides 5 and therefore on the outlet openings 6, and in particular also on the type and the volume of the material 3 to be heated. It can therefore be possible to use only a small number of magnetrons 4, wherein at least two have to be arranged. These then form a row in an arbitrary direction. However, it is preferably provided that at least multiple magnetrons 4 are arranged in a row R and can be controlled by means of the control or regulating device 17 using a differentiated power profile 9. One row R, possibly not necessarily transverse but at an angle (not parallel) to the production direction, already enables the differentiated heating of the material 3 over the width 19.

[0044] Furthermore, the main axes 23 of two outlet openings 6 are shown by way of example in the left lower corner in FIG. 2. In this exemplary embodiment, the main axes 23 of the rectangular outlet openings 6 form an angle of 90 in relation to one another. Viewed from the left lower outlet opening 6, the outlet opening 6 arranged adjacent thereto in the same series R1 forms the closest neighbor transversely in relation to the production direction 15, the outlet opening 6 arranged in the row S2, in which the main axis 23 is shown, forms the closest neighbor in the production direction 15.

[0045] Two adjacent openings 6 are also shown indicated by way of example in the right upper corner in FIG. 2, the focal points 24 of which (shown by dots) of the areas of the outlet openings 6 are connected by the connecting line 25. This connecting line 25 encloses an angle in relation to the perpendicular on the production direction 15.

[0046] According to FIG. 3, a second radiation chamber 14 can be provided, which is arranged opposite to the first radiation chamber 14 with respect to the material 3 and therefore below the transportation belt 10. It can preferably have the same configuration of magnetrons/waveguides/outlet openings as the radiation chamber 14. The material 3 to be heated here has a predefined width 19 and rests on the transportation belt 10 traveling through the continuous furnace 1. The material 3 is formed essentially strand-shaped, has two flat sides, and one edge 7 on each side.

LIST OF REFERENCE SIGNS

[0047] 1 continuous furnace [0048] 2 press [0049] 3 material [0050] 4 magnetron [0051] 5 waveguide [0052] 6 outlet opening [0053] 7 edge [0054] 8 product [0055] 9 power profile [0056] 10 transportation belt [0057] 11 housing [0058] 12 absorber [0059] 13 cabinet [0060] 14 radiation chamber [0061] 15 production direction [0062] 16 measuring device [0063] 17 control or regulating device [0064] 18 measuring device [0065] 19 width [0066] 20 measuring device [0067] 21 longitudinal center line [0068] 22 cover [0069] 23 main axis [0070] 24 focal point [0071] 25 connecting line [0072] R row of the outlet openings transversely in relation to 15 [0073] S column of the outlet openings in 15 [0074] L power of 4