EP3458247A1

EP3458247A1 - Apparatus for heating plastics preforms with travelling top emitter

Info

Publication number: EP3458247A1
Application number: EP17749732.8A
Authority: EP
Inventors: Wolfgang Schönberger
Original assignee: Krones AG
Current assignee: Krones AG
Priority date: 2016-08-09
Filing date: 2017-08-09
Publication date: 2019-03-27
Also published as: US20190134879A1; CN109476069A; WO2018029283A1; DE102016114739A1

Abstract

The invention relates to an apparatus for heating plastics preforms (3), having a transporting device (20) which transports the plastics preforms (3) along a predetermined transport path (TR1, TR2), having a heating device (40) which at least temporarily heats the plastics preforms (3), wherein the heating device (40) at least comprises: ⋅ - a bottom heating element (4115) which is suitable and intended for heating a bottom portion (B) of the plastics preforms (3), ⋅ - a reflector element (4113) which is fitted under the bottom portion (B) of the plastics preforms (3) in the longitudinal direction (L) of the plastics preforms (3) and reflects thermal radiation onto the plastics preforms (3), ⋅ - an adjusting device (50) which is suitable and intended for adjusting the reflector element (4113) in the longitudinal direction (L) of the plastics preforms (3), and wherein the apparatus has a control device which is suitable and intended for automatically switching at least one heating element (4110) on and/or off depending on the position (S3, S2) of the reflector element (4113) with regard to the longitudinal direction (L) of the plastics preforms (3).

Description

Apparatus for heating preforms with moving Topstrahler

description

The present invention relates to an apparatus and a method for heating plastic preforms. Such devices and methods have been known for a long time from the prior art. In the beverage-producing industry, it is customary that plastic preforms, for example by means of blow molding machines, be formed into plastic containers. For this purpose, the plastic preforms are first heated in an oven and then fed in this heated and therefore soft state of the respective blow molding machine. In the context of this heating, it is possible that the plastic preforms are transported along a predetermined transport path and thereby heated by heaters.

Devices for heating plastic preforms are known from the prior art, which have a heating element for heating the bottom portion of the plastic preforms. As a heating element, in particular so-called top radiators are used according to the prior art. These are fixed and position-specifically installed and can only be changed manually in a small height range.

It is also known, below the plastic preform to be heated to install a floor reflector, which reflects the heat radiation to the plastic preform. For example, from EP 2 561 972 B1 it is also known that this floor reflector can be designed to be adjustable. Such adjustment allows adaptation to different lengths plastic preforms and a resulting improvement in energy efficiency. However, the manual adjustment of the top emitter is complex and time-consuming and is therefore not set according to the prior art in dependence on the respective length of the plastic preforms, or not installed and removed. This results in deterioration of the heating profile and a deterioration of the energy efficiency. This effect occurs especially with short plastic preforms.

In addition, when using a permanently installed top spotlight no adjustment of the ground reflector longer possible because of the risk of collision. The lack of adjustment of the floor reflector also contributes to a deterioration of the heating profile and the energy efficiency.

The invention is therefore based on the object to provide a device and a method available that allows an energetically improved heating of the plastic preforms, especially in the bottom area.

This object is achieved by the subjects of the independent claims. Advantageous embodiments and further developments are the subject of the dependent claims. A device according to the invention for heating plastic preforms has a transport device, which transports the plastic preforms along a predetermined transport path, and a heating device, which heats the plastic preforms at least temporarily. The heating device has at least one bottom heating element, which is suitable and intended to heat a bottom portion of the plastic preforms, a reflector element which is mounted in the longitudinal direction of the plastic preforms below the bottom portion of the plastic preforms and reflects heat radiation to the plastic preforms, and an adjusting device to which is suitable and intended to adjust the reflector element in the longitudinal direction of the plastic preforms. According to the invention, the bottom heating element is arranged on the reflector element and / or can be adjusted together with it. It should be noted that the arrangement of the reflector element is present below the bottom portion in the case in which the plastic preforms are transported with their mouth up. But there are also known devices in which the plastic preforms are transported with their mouths down. In these cases, the reflector element is arranged above the bottom section. Generally, the reflector element is preferred in a longitudinal direction of the Plastic preforms arranged next to the plastic preforms, but closer to the bottom portion than at the mouth.

The bottom heating element is preferably designed as a radiation element, particularly preferably as a so-called top radiator, as is known in the prior art for heating the plastic preforms.

Preferably, the transport device is suitable and determined to transport the plastic preforms occasionally. In addition, the transport device is preferably a circulating transport device. This transport device can have a circumferential chain on which a plurality of holding devices for holding the plastic preforms is arranged. These holding means can be embodied as holding mandrels, which are suitable and intended to intervene in the mouths of the plastic preforms in order to hold them.

In a further advantageous embodiment, the device also comprises turning means, which are suitable and intended to rotate the plastic preforms around their longitudinal directions. The heating element is preferably a radiant heater and more preferably an infrared radiant heater.

Preferably, the bottom heating element is adjusted by the same adjusting device, which is suitable and intended to adjust the reflector element in the longitudinal direction of the plastic preforms. In particular, this adjusting device has a drive. The drive can be a hand crank, an electric motor or another drive, such as a hydraulic or pneumatic drive. The adjusting device preferably allows an adjustment of at least the reflector element in the longitudinal direction of the plastic preforms.

Particularly preferably, the reflector element is designed to be automatically movable. In this case, it is also conceivable, in particular, that the device has a bottom reflector detection device and a preform length detection device. The ground reflector detection device can preferably detect the position and in particular the height of the reflector element. The preform length detection device for detecting the length of the plastic preforms is advantageously arranged in the transport direction upstream of a first reflector element. Advantageously, the device further comprises a control device which can receive a detection signal of the ground reflector detecting means and the preforming length detecting means. The control device preferably controls the adjusting device as a function of these received signals. Advantageously, the bottom heating element is integrated in the automatically movable reflector element. In particular, the bottom heating element can be arranged with a defined distance on the reflector element or be embedded with a defined depth in the reflector element. It would also be conceivable that the distance between the bottom heating element and the reflector element is adjustable. However, in this embodiment as well, the distance between the bottom heating element and the reflector element is preferably clearly definable. In this way, the optimum distance of the reflector element or the Bodenheizelements can be adjusted to the bottom portion of the plastic preform to minimize the energy consumed even with different lengths of plastic preforms. In an advantageous embodiment, the heating device has further heating elements, which are preferably arranged one above the other in the longitudinal direction of the plastic preforms. These further heating elements preferably heat the entire plastic preform as uniformly as possible in the longitudinal direction. Advantageously, the other heating elements can be operated separately. In this way, the area heated by the heating elements can be optimally adapted to the plastic preform. In particular, it can be avoided that - especially in the case of short plastic preforms - an area outside the plastic preform is irradiated and thus heated. This prevents on the one hand overheating of the heater and on the other hand allows a particularly energy-saving operation of the device.

In order to realize a common height adjustment of the bottom heating element and the reflector element, the electrical contacting of the bottom heating element is preferably separated from the actual radiator support, in particular a heating box, and designed as a separate supply or contacting. The electrical contacting of the further heating elements is preferably carried out via the actual radiator support. Advantageously, the electrical contacting of the Bodenheizelements under a floor element as in particular but not exclusively laid a floor tile to limit the thermal stress on these components. In particular, the electrical contact is located below the reflector element and / or the Bodenheizelements. Preferably, the cable guide is placed below the reflector element. Advantageously, this cable guide is designed at least partially flexible. In a further advantageous embodiment, the device has further reflector elements, which likewise reflect heat radiation on the plastic preforms. This radiation may in particular be radiation which, if appropriate, does not first reach the plastic preforms but is subsequently directed by the said reflection onto the plastic preforms. In particular, it would be conceivable that the device has side reflectors, which are arranged with respect to the plastic preforms on the opposite side of the other heating elements, and / or side reflectors, which are arranged with respect to the plastic preforms behind the other heating elements.

In an advantageous embodiment, the heat radiation is reflected by the reflector element in particular on the bottom portion of the plastic preforms. All reflector elements may be polished or mirrored sheets, in particular of aluminum, which directly reflect radiation, and / or ceramic reflectors which absorb the radiation and then release it again as heat.

The device can preferably be used both passively, with the floor heating element switched off, and also actively with the floor heating element switched on.

Advantageously, the heat radiation of the heating device is infrared radiation. The further heating elements may in particular be infrared tubes. Advantageously, these infrared tubes extend in the direction of the transport path of the plastic preforms and in particular in a straight direction.

In an advantageous embodiment, a multiplicity of individual heating modules can be provided along the transport path of the plastic preforms. Preferably, a bottom heating element and further heating elements are arranged within each heating module. Advantageously, each heating module is regulated separately.

The object on which the present invention is based is likewise achieved by a device for heating plastic preforms with a transport device which transports the plastic preforms along a predetermined transport path, with a heating device which at least temporarily heats the plastic preforms, wherein at the heating device at least one reflector element which is mounted in the longitudinal direction of the plastic preforms below the bottom portion of the plastic preforms and heat radiation to the plastic preforms, an adjusting device which is suitable and intended to adjust the reflector element in the longitudinal direction of the plastic preforms and at least one heating element and preferably a plurality of heating elements, which are preferably arranged one above the other in the longitudinal direction of the plastic preforms comprises. Preferably, the heating element and particularly preferably the heating elements are arranged in relation to the transport path of the plastic preforms laterally of the transport path.

According to the invention, the device has a control device which is suitable and intended, depending on the position of the reflector element, preferably with respect to the longitudinal direction of the plastic preforms, at least one heating element automatically turn on and / or turn off and / or preferably automatically an attachment of at least one Block heating element and / or release a blocked connection of at least one heating element. In this case, the device can be equipped with all features in connection with the device described above individually or in combination and vice versa. Such a proposed automatic switch on and / or off has the advantage that incorrect operation of the heating elements (by an operator) can be ruled out and thus destruction of the heating elements and / or floor elements or tiles, as well as a risk of fire in the event of that connected heating elements are located below the reflector element, can be excluded. Such an arrangement of connected heating elements below a reflector element can therefore be so dangerous because, for example, electrical supply lines can be arranged below the reflector element. In particular, in the case of an arrangement of floor heating elements on movable or adjustable reflector elements, it has proved to be advantageous to wire the electrical connection of the floor heating elements directly to the heating divider. Preference is given in each case to two safety-related shutting off treasures for the galvanic separation of the floor heating elements from the heating controller as soon as the protected area is opened.

When switching off a heating element, it is preferred not only to transfer the heating element from a heating operation or state of the heating element (ie, in which the heating power is not zero) to a non-heating state, in which the heating element is preferably powered by its power source or heating element Energy source is disconnected or in which the heating tion of the heating element is zero, understood, but also a transfer to a deactivated state in which preferably the heating element is not (by an operator or without prior release) can be connected. Preferably, turning on a heating element does not only mean its "actual turn-on", ie the displacement of the heating element into a heating operating state (in which the heating power of the heating element has a predetermined value other than zero), but by switching on a heating element The heating element can also be understood as meaning the release of a heating element that can not be activated or blocked or can not be switched on or not (by an operator) into a heatable state, that is to say an activatable state Whether (at least) one heating element or preferably a plurality of heating elements are in a heating state and, depending on the position of the reflector element automatically an "actual shutdown", ie the transfer to a non-heating state, and / or an "actual turn on", ie the overf lead to a heating state.

With regard to the transport path of the plastic preforms, the device preferably has at least one further bottom element located behind (downstream compared to) the (first) bottom element and adjustable by an adjusting device with respect to the longitudinal direction of the plastic preforms. Preferably, the device has at least one further heating element and preferably further heating elements, which are arranged with respect to the transport path of the plastic preforms behind (downstream compared to) the at least one heating element, and are preferably arranged with respect to the transport path of the plastic preforms laterally next to the transport path and are preferably arranged one above the other at least partially with respect to the longitudinal direction of the plastic preforms. In this case, a plurality of heating elements, which are preferably arranged one above the other in relation to the longitudinal direction of the plastic preforms, may be arranged together in a so-called heating box. In the following, the invention will be described only with respect to a reflector element or with respect to a bottom heating element or with respect to a heating box. It goes without saying, however, that the individually described features or combinations thereof can also be transferred to further reflector elements or floor heating elements or further heating boxes.

In an advantageous embodiment, the control device is suitable and intended, at least one heating element and preferably all heating elements, the (or) in relation to the longitudinal direction of the plastic preforms below the reflector element (or the current position of the reflector element) is arranged (or are), in particular automatically turn on and / or turn off. It is also conceivable that a safety distance is predetermined and the control device checks whether this predetermined safety distance between the position of the reflector element and at least one heating element and preferably for each heating element is maintained, and in the case that this distance is exceeded by a heating element, the corresponding heating element is switched off. It is thus proposed that a possible switching on of heating elements or lamps (of a heating box), which are located below the top radiator or of the floor element, be prevented or already switched on heating elements are switched off.

In an advantageous embodiment, the heating device has at least one bottom heating element, which is preferably arranged on the reflector element and which is suitable and intended to heat a bottom portion of the plastic preforms, wherein the control device is suitable and determined, depending on the position of the bottom heating element with respect to the longitudinal direction of the plastic preforms automatically turn on at least one heating element and / or turn off. Preferably, the control device is suitable and determines, at least one heating element and preferably all heating elements (or the) in relation to the longitudinal direction of the Kunststoffvor- molded products below the Bodenheizelementes (or the current position of the Bodenheizelementes) is (or are ), switch off. It is also conceivable that a safety distance is predetermined and the control device checks whether this predetermined safety distance between the position of the Bodenheizelementes and at least one heating element and is preferably maintained for each heating element, and in the case that this distance is exceeded by a heating element , the corresponding heating element is switched off.

In a further advantageous embodiment, in response to a signal transmitted by the adjusting device, which preferably contains information about a current position and / or a planned position of the reflector element and / or the floor heating element, the control device switches on at least one heating element automatically and / or or at.

In a further advantageous embodiment, the device has a sensor device for detecting a position of the reflector element and / or a position of the floor heating element. element, wherein the control device automatically switches on and / or off depending on a detected by the sensor device position at least one heating element. In a further advantageous embodiment, the control device is suitable and determined to automatically switch on and / or off at least one heating element as a function of the (longitudinal) extent of the plastic preforms in relation to the longitudinal direction of the plastic preforms. Depending on the (longitudinal) extent of the plastic preforms, the control device preferably switches off all heating elements arranged at a height with respect to the longitudinal direction of the plastic preforms. For determining the affected (off and / or to be switched on) heating elements or lamps preferably the prescription-dependent target position (depending on the length of the plastic preforms) of the assembly of the movable floor tile is used. In conjunction with the lamp spacings or distances of the heating elements entered in the mechanical adjustment values, it is then possible to calculate which lamp zones or which heating elements below or above a bottom heating element and / or a

Reflector element are arranged. The device, in particular the heating device, can preferably only be switched on when the reflector elements or the floor tiles have reached their (predetermined) desired position.

In a further advantageous embodiment, the control device blocks depending on the position of the reflector element with respect to the longitudinal direction of the plastic preforms and / or depending on the position of a Bodenheizelementes with respect to the longitudinal direction of the plastic preforms an attachment of at least one heating element and / or releases a blocked connection. This offers the advantage that an unwanted, manual intervention of an operator can be prevented.

Preferably, the control device is suitable for this purpose and determines, on an operating device for operating the device, in particular the heater, on and off switchability of a heating element and preferably all heating elements, depending on the position of the reflector element (or the reflector elements) with respect to Longitudinal direction of the plastic preforms and / or depending on the position of a Bodenheizelementes with respect to the longitudinal direction of the plastic preforms to activate and / or deactivate. Preferably, a switched on and / or switched off state and / or an activated and / or deactivated state, in which preferably by an operator no switching off and / or on is possible, of a (visual) display device of a heating element or the heating elements (optically) are output. This can be done, for example, by dousing these heating elements or lamps, for example in a lamp matrix of the user interface, in the operating device, so that they can preferably no longer be switched on. A possible switching is further preferably prevented by the fact that the lamps or the heating elements are monitored in the controller and actively switched off, should one of these hazardous heating elements or lamps anyway be turned on, for example, after a recipe change with different plastic preform lengths and thus different positions Reflector elements or the floor tiles. In addition, the heating power or the zone power of the heating elements or of the lamps below the reflector element or the floor tile is preferably set to 0%.

Preferably, the Bodenheizelement or preferably the Bodenheizelemente are independent of the position of the reflector element or the reflector elements used or can be turned on and off or. Preferably, in an operating device and / or the display device, the position of a Bodenheizelementes, preferably all Bodenheizelemente (based on the transport path of the plastic preforms and / or also with respect to the longitudinal direction of the plastic preforms), for example in the lamp matrix, characterized or visualized, for example by marking with a "T" in the lamp matrix.

The present invention is further directed to a method for heating plastic preforms, wherein the plastic preforms are transported by a transport device along a predetermined transport path and heated by a heating device at least temporarily. The bottom portion of the plastic preforms is thereby heated at least by a Bodenheizelement. A reflector element, which is mounted in the longitudinal direction of the plastic preforms below the bottom portion of the plastic preforms, reflects heat radiation on the plastic preforms. This reflector element can be adjusted by an adjusting device in the longitudinal direction of the plastic preforms.

According to the invention, the bottom heating element is arranged on the reflector element and / or can be adjusted together with it.

In this case, the device described above is set up in particular and intended to carry out this method, ie all of the devices described above features are also disclosed for the method described here and vice versa.

Advantageously, the bottom heating element is adjusted together with the reflector element as a function of the length of the plastic preform to be heated. This leads to a better energy input in Preformkuppe, since so the Bodenheizelement and the reflector element based on the respective driven different lengths of the plastic preforms can be made quickly, easily and close. The plastic preforms are preferably heated by further heating elements, which are preferably arranged one above the other in the longitudinal direction of the plastic preforms.

In an advantageous embodiment, these further heating elements and the bottom heating element are supplied separately from each other with electricity.

The present invention is further directed to a method for heating plastic preforms, wherein the plastic preforms are transported by a transport device along a predetermined transport path and heated by a heating device at least temporarily. A reflector element, which is mounted in the longitudinal direction of the plastic preforms below the bottom section of the plastic preforms, reflects thermal radiation onto the plastic preforms. This reflector element can be adjusted by an adjusting device in the longitudinal direction of the plastic preforms.

According to the invention, depending on the position of the reflector element with respect to the longitudinal direction of the plastic preforms, at least one heating element is automatically switched on and / or switched off and / or activated and / or deactivated. In this case, the device described above is particularly adapted and intended to carry out this method, i. that all the features implemented for the device described above are also disclosed for the method described here, and vice versa. Also, the method may be equipped with all the features associated with the above-described method singly or in combination, and vice versa.

In this case, the bottom section of the plastic preforms is preferably also heated by a bottom heating element, and is particularly preferably heated as a function of the position. tion of the Bodenheizelementes with respect to the longitudinal direction of the plastic preforms at least one heating element automatically turned on and / or off and / or activated and / or deactivated. Further advantages and embodiments will be apparent from the attached drawings:

Show:

Fig. 1 is a schematic plan view of a part of a blow molding machine;

Fig. 2 is a schematic partial view of a device according to the prior art;

3 shows a schematic partial view of a device according to the invention with adjustable bottom heating element;

4 is a perspective view of an adjusting device;

Fig. 5 is a sectional view of the adjusting device;

6 is a perspective view of the adjusting device and power supply of

bottom heater;

7 shows a sectional view of the adjusting device and power supply of the floor heating element;

8 shows an illustration of an operating device;

9a, b, c show two illustrations of a device with an adjustable reflector element in a lowest state and a representation of a method according to the invention; and

10a, b, c two representations of a device with an adjustable reflector element in a raised state and a representation of a method according to the invention. Fig. 1 shows a part of a blow molding machine 1 for the production of containers 2 from preforms 3 made of plastic, such as polyethylene terephthalate (PET), polypropylene (PP), etc., in which the device according to the invention can find application. The finished containers 2 may be bottles, for example, as shown in Fig. 1, in which a product can be filled. The product may in particular be a beverage, a cleaning agent, etc. The preforms 3 are shown in Fig. 1 as circles for their mouth, with the sake of clarity, only two of the preforms 3, at the beginning (in Fig. 1 below) and at the end (left in Fig. 1) of the row formed by them are provided with a reference numeral.

The blow molding machine 1 in FIG. 1 comprises a first transport device 10, a second transport device 20, a third transport device 30, a heating device 40 and a blowing device, not shown, which is arranged downstream of the third transport device 30. In the blowing device, not shown, the preforms 3 heated by the heating device 40 can be blown into the desired shape of the container 2 by blowing in a gaseous medium. The blow molding machine 1 may in particular be a stretch blow molding machine. In addition, in FIG. 1, a bottom reflector detector 80 and a preform length detector 90 are shown schematically at the inlet of the heater 40.

The first, second and third transport means 10, 20, 30 are respectively for transporting the plurality of preforms 3 shown in Fig. 1. Here, the preforms 3 are each in the transport direction of the first to third transport means 10, 20, 30 in a row one behind the other arranged. The first transport device 10 is formed in FIG. 1 as a sawtooth star, which is rotatably mounted, as indicated in Fig. 1 with a rotary arrow on the first transport device 10. The first transport device 10 transfers the preforms 3 held by it to the second transport device 20.

The second transport device 20 is a conveying path along which a first heating section 41 and a second heating section 42 of the heating device 40 are arranged and between which see the heating device 40 has a deflection region 43. The first and second heating sections 41, 42 are each linear heating sections. In the deflection region 43, in which the preforms 3 are guided along a half-arc, the preforms 3 are deflected by a first transport direction TR1 in a second transport direction TR2. The first transport direction TR1, in which the preforms 3 are transported through the first heating path 41, is directed in FIG. 1 opposite to the second transport direction TR2, in which the preforms 3 are transported through the second heating path 42. In the second transport device 20, the preforms 3 are held at their mouth by a spindle which is rotatably mounted in a chain link. There are several chain links, with the spindles mounted therein, connected to each other, so that the chain links form an endlessly circulating chain and thus the conveying path of the second transport device 20. After passing through the second heating section 42, the preforms 3 are transferred from the second transport device 20 to the third transport device 30, which is also rotatably mounted and further transports the preforms 3 heated by the heating device 40 to the blowing device (not shown). The preforms 3 are therefore heated by the heating device 40, while they are transported by the second transport device 20 through the heating sections 41, 42, as described in more detail below.

Here, the preforms 3 are rotated by means of the spindle about its axis, as indicated in Fig. 1 by small white rotary block arrows. The first heating section 41 is used for the first heating of the preforms 3. In this case, the preforms 3 are heated uniformly on the circumference. The first heating section 41 has a multiplicity of heating modules, namely a first heating module 41 1, a second heating module 412, a third heating module 413, a fourth heating module 414, a fifth heating module 415, a sixth heating module 416, and a seventh heating module 417. The heating modules 41 1 to 417 are arranged in this sequence in the direction of the first transport direction TR1 in a row one behind the other.

The number of heating modules 41 1 to 417 is individually adjustable and depends on the required heating time or on the number of heating elements. The second heating section 42 is used for the second heating of the preforms 3. Here, the preforms 3 are heated to the final temperature at which they can be converted into a container 2 by means of the blowing device, not shown. The final temperature is also referred to as the forming temperature of the preforms 3.

The second heating section 42 also has a plurality of heating modules, namely, a first heating module 421, a second heating module 422, a third heating module 423, a fourth heating module 424, a fifth heating module 425, a sixth heating module 426, and a seventh heating module 427. The heating modules 421 to 427 are arranged in this sequence in the direction of the second transport direction TR2 in a row one behind the other. In the deflection region 43, no heating of the preforms 3 takes place by means of heating sections or heating modules. The heating modules 41 1 to 417 of the first heating section 41 and the heating modules 421 to 427 of the second heating section 42 are shown in FIG. 1 for the purpose of simplifying the representation, respectively, as being arranged outside next to the conveying path formed by the second transport device 20.

Fig. 2 shows a section, in the direction of the arrows A AA along the thick dashed line in Fig. 1, through the first heating module 41 1 of the first heating path 41 according to the embodiment of the prior art. The heating modules 412 to 417 of the first heating section 41 and the heating modules 421 to 427 of the second heating section 42 are each constructed in the same way as the first heating module 41 1 of the first heating section 41, so that their structure is also based on the description of the first Heating module 41 1 is referenced.

The first heating module 41 1 has a plurality of heating elements 41 10, which are arranged in Fig. 2 on the right side of the preforms 3. The plurality of heating elements 41 10 are arranged one above the other in a row. In FIG. 2, for the sake of clarity, only the uppermost and lowermost heating element 41 10 are provided with a reference numeral. In addition, each heating element 41 10 is an elongated radiator whose length is arranged in the direction of the first transport direction TR1 and extending in the direction of the first transport direction TR1. Each heating element 41 10 serves to radiate heat radiation or heating radiation onto the preform 3, which heats the preform 3.

On the left side of the preform 3, a counter-reflector 41 1 1 is arranged, which extends both in the direction of the length L of the preform 3 (in Fig. 2, the vertical) and in the direction of transport direction TR1. The counter reflector 41 1 1 reflects the heat radiation not absorbed by the preforms 3 back to the preform 3 and the front and behind arranged preforms 3. In addition, a back reflector 41 12 is provided on the side of the heating element 41 10, which also not yet of the Preheat 3 recorded heating radiation back to the preform 3 and the front and behind arranged preforms 3 reflected.

In addition, a reflector element 41 13 is arranged below the preform 3, which also reflects the heat radiation not picked up by the preforms 3 again to the preform 3 or the preforms 3 arranged in front of and behind it. The reflector element 41 13 reflects the heating radiation, in particular in the direction of the bottom portion B of the preforms 3 to be heated. The reflector element 41 13 is transverse to Rear reflector 41 12 and the counter reflector 41 1 1 arranged. Cross here means that the arrangement of the reflector element can deviate by up to 10 ° from the exact transverse direction. In addition, a bottom heating element 41 15 is provided, which is arranged between the bottom portion B of the preform 3 and the reflector element 41 13. For example, depending on the length of the plastic preform, the bottom heating element may be attached to either 41A or 41B. In the case of a change in the length of the plastic preforms, this requires, according to the prior art, a conversion or a relatively cumbersome adjustment of the bottom heating element 41 15 from the position 41 15A to 41 15B or vice versa.

FIG. 3 shows the section of FIG. 2 through the first heating module 41 1 of the first heating path 41 in the case of a device according to the invention with an adjustable bottom heating element. Again, the preform is heated by the heating elements 41. However, the bottom heating element 41 15 is arranged on the reflector element 41 13 in the device according to the invention. The reflector element 41 13 can be adjusted by the adjusting device 50 to the preform 3 to or from this. The bottom heating element 41 15 is thereby adjusted together with the reflector element 41 13 of the adjusting device 50.

In this way, the heating radiation can be used particularly effectively for heating preforms of different sizes. By one hand, the reflector element 41 13 can be moved relatively close to the bottom portion B, it is ensured that hardly any heat radiation is lost unused. In addition, by the distance between the bottom portion B of the preform 3 and the Bodenheizelement 41 15 is variable, the bottom portion B can be heated specifically targeted. In this way, the distance between the bottom portion B and the Bodenheizelement 41 15 and the reflector element 41 13 with respect to the utilization of the heating radiation of the heating elements 41 10 and 41 15 can be optimally adjusted.

In the embodiment shown in FIG. 3, the bottom heating element 41 15 is arranged at a defined distance on the reflector element 41 13. However, an embodiment would also be conceivable in which the bottom heating element 41 15 is embedded in the reflector element 41 13 at a defined depth. For further energy saving, the lower heating elements 41 10 can be deactivated in the heating of shorter preforms 3, for example, switched off or alternatively moved away and turned off, so that only the heating elements 41 10 are used for heating the preforms 3, which is actually for the Heating the preforms 3 are needed. That is, the lower heating elements 41 10 are used only in heating a longer preform, whereas they are not used in the heating of a shorter preform.

4 and 5 show an adjusting device 50 of the blow molding machine 1, with which the reflector element 41 13 of the heating module 41 1 and together with it all other floor reflector elements of the heating modules 412 to 417 and 421 to 427 in their position, in particular their height , can be adjusted. Alternatively, a single, continuous reflector element 41 13 may be provided in each heating section 41. In FIG. 4 and FIG. 5, to simplify the illustration, only the heating module 41 1 of the first heating section 41, its reflector 41 13, the reflector element 4123 of the second heating module 412 of the first heating section 41, the reflector element 4133 of the third heating module 413 first heating section 41, the reflector element 4213 of the first heating module 421 of the second heating section 42, the reflector element 4223 of the second heating module 422 of the second heating section 42, and the reflector element 4233 of the third heating module 423 of the second heating section 42. The reflector element 41 13, the reflector element 4123 and the reflector element 4133 of the first heating path 41 are supported by two rods 51, which are designed as threaded spindle. The two rods 51 are a first support means for supporting the reflector elements 41 13, 4123, 4133 of the first heating section 41. The reflector elements 4213, 4223 and 4233 of the second heating section 42 are supported by two further rods 52, which are also designed as a threaded spindle. The two bars 52 are a second support means for supporting the reflector elements 4213, 4223, 4233 of the second heating path 42. The bars 51 and 52 and the first and second support means 51, 52 are by means of a belt 53 placed around them with each other and with an An - Drive device 54 coupled. The belt 53 is a coupling device for coupling the first and second support means 51, 52 with the drive means 54. Thus, a drive of the belt 53 caused by the drive means 54 causes rotation of the rods 51, 52 about their axis, causing a common and synchronous adjustment all reflector elements of the heating modules of the first and second heating section 41, 42 result. The reflector elements of the heating modules of the first and second heating sections 41, 42 can so be adjusted centrally. The drive device 54 may be, for example, an electric, pneumatic or electromechanical actuator device.

The adjustment of the position of the reflector elements of the heating modules 41 1 to 417 and 421 to 427 by means of the adjusting device 50 can make an operator by switch or button of a control panel of the heater 40 or the blow molding machine 1. That is, the adjustment of the position of the floor reflectors by means of the adjusting device 50 is carried out automatically. Advantageously, it is a stepless fine adjustment, which can thus be optimally adapted to each length of the preforms 3.

Alternatively, the reflector elements of the heating modules 41 1 to 417 and 421 to 427 may be automatically adjusted with the adjusting device 50. In this case, the adjusting device 50 is controlled by a control device (not shown) of the blow molding machine 1. For the control of the blow molding machine 1, the control device can access, for example, the determined values of the ground reflector detection device 80 and the preform length detection device 90.

FIGS. 6 and 7 are also illustrations of the adjusting device 50. In these illustrations, in particular, the power supply of the Bodenheizelements 41 15 is shown. On the re-presentation of the heating module 41 1 was omitted for reasons of clarity.

Unlike an embodiment which has only one reflector element 41 13 below the preform 3, a bottom heating element 41 15 requires an electrical contact. However, this electrical contacting of a bottom heating element 41 15 preferably does not take place as in the prior art (FIG. 2) together with the further heating elements 41 10. A disadvantage of the prior art shown in FIG. 2 lies in the fact that an adjustment of the bottom heating element 41 15 can not be done or only by cumbersome conversion.

The figures therefore show that the electrical contact 41 16 (cf., FIG. 7) of the bottom heating element 41 15 is preferably designed separately from the contacting of the further heating elements 41 10. In order to limit a thermal load of the corresponding components, the electrical contact 41 16 of the Bodenheizelements 41 15 is preferably placed under the reflector element 41 13 and below the bottom heating 41 41. The electrical line 41 18, which supplies all Bodenheizelemente 41 15, 4125, 4135, etc., Therefore, also runs below the reflector elements 41 13, 4123, 4133 etc. Preferably, the electrical line 41 18 extends substantially parallel to the plane of the reflector element 41 13, 4123, 4133 etc. Also below the reflector elements extends the cable guide 41 17. The cable guide 41 17th leads the electrical line 41 18, starting from the adjusting device 50, in particular starting from one of the rods 51, to the underside of the reflector elements, below which the electrical line 41 18 is continued in parallel. The cable guide 41 17 is preferably at least partially flexible designed so that the electrical line 41 18 may be immovably disposed on the adjusting device 50. Due to the flexibility of the cable guide 41 17 is still possible that the reflector elements and floor heating with constant good electrical contact can be adjusted by the adjusting device 50 in height. FIG. 8 shows an illustration of an operating device 60. It can be seen here that the heating device 40 has a multiplicity of heating boxes, which are arranged one behind the other along the transport path of the plastic preforms 3 and past which the individual plastic preforms are transported. The reference numeral 62 indicates the numbers assigned to the heating boxes. The juxtaposed Heizkäs- th along the transport path of the plastic preforms are arranged one behind the other. Each of these heating boxes in this case has a plurality of heating elements 41 10, which are arranged one above the other in the longitudinal direction L of the plastic preforms 3. It can be seen here from the status displays of the individual heating elements represented by empty squares 70 that in the heating zones 6 - 9 or the heating elements 41 10 of these heating zones are respectively switched off. Hatched squares 72 represent a switched-on state of the respective heating element 41 10. In the other heating zones 1-5, the respective heating elements of the heating cabinets 62 are partially switched on and off. In particular, an operating state of the heating elements 41 10 shown in FIG. 8 is suitable for shorter plastic preforms whose extent along their longitudinal direction L does not extend into the zones 6 to 9. The reference numeral 64 indicates (percentage) information about the heating power of the various heating zones or lamp zones. The heating zones result from the same height with respect to the longitudinal direction of the plastic preforms, with respect to the transport path one behind the other arranged heating elements (various heating boxes 62). Through the use of movable Topstrahler or one (in the longitudinal direction L) adjustable Bodenheizelementes 41 15 now the situation may arise that the Topstrahler or the bottom heating element 41 15 in the radiator region of the lamps attached to the heating box or at least one heating element 41 10 of a heating box can be positioned. Although with a correctly set heating profile, preferably no lamp or heating element 41 10 is activated, which can heat the top radiator or bottom heating element 41 15 from the side or below, but this is not the case on the user interface 60 of the lamp matrix or operating device 60 seen. Also lamps of the zones or heating elements of the zones below the floor tiles or below at least one reflector element 41 13 can be activated. Here, the information of the position of the reflector element is missing and all heating elements 41 10 can always be selected. The operator does not notice, if he has a lamp or a heating element 41 10 below the top radiator or the Bodenheizelementes 41 15 and / or below the reflector element 41 13 turned on. If a lamp is switched on below the top radiator or the bottom heating element 41, its power cable, which is preferably laid along the reflector element or the floor tile, can overheat and even catch fire. The switching on of lamps or heating elements 41 10 below a reflector element 41 13 or the floor tile harbors an even higher risk potential, since there is no thermal barrier to heat-sensitive components. There is an acute fire hazard. FIGS. 9a and 9b show two side views of a device, in this case a heating box, with a reflector element 41 13 which can be adjusted by an adjusting device 50 and which is here in each case in a lowest state relative to the longitudinal direction of the plastic preforms. The floor tiles or the reflector elements are so completely shut down here and all lamps or heating elements 41 10 are free, ie above the floor tile or the reflector element 41 13 arranged. 9a shows a device or a heating box without a bottom heating element 41, while in the device shown in FIG. 9b or illustrated heating box, a bottom heating element 41 is arranged on the reflector element 41 or a floor tile. By means of the operating device 60 or display device shown in FIG. 9c, a method according to the invention is illustrated. Since all heating elements 41 10 are arranged above the reflector element 41 13, all heating elements 41 10 may be used to heat the plastic preforms 3, so it may be all 41 10 10 connected by an operator. This can be seen on the operating device 60 or display device in that exclusively the symbols 70, 72 are used as operating elements for the individual heating elements 41, which (exclusively) indicate whether the respective heating element 41 10 is switched on or off. In this case, the reference numeral 70 denotes an off state of the relevant heating element 41 10 and the reference numeral 72 is a switched-state of the relevant heating element 41 10. Basically, however, the heating power of all heating elements 41 10 can be changed by the operator. In addition, in the operating device 60, a position of the top radiators or of the bottom heating elements 41 15 with respect to the transport path of the plastic preforms or with respect to the respective heating box 62 is indicated by the symbol "T." The top radiators or bottom heating elements 41 15 are always usable regardless of the bottom tile position or the position of the reflector elements 41 13. The arrow P1 now illustrates a possible adjustment of the heating powers of the heating elements 41 10 of a heating box shown in Fig. 9a, in which no bottom heating element 41 15 is present, and (straight ) also no heating element 41 10 is switched on, but all can be switched in. The arrow P2 illustrates a possible adjustment of the heating powers of the heating elements 41 10 of a heating box shown in Fig. 9b, in which the bottom heating element 41 15 is present and this in the Operating device 60 and a display device by a symbol 74 "T" is, and (just) no heating element 41 10 is turned on, but all can be turned on.

Figures 10a and 10b show two side views of the device, in particular a heating box, with an adjustable reflector element 41 13, which is now to be used for heating a shorter plastic preform 3 (compared to about the plastic preforms 3 shown in Figures 9a and 9b). For this purpose, the reflector element 41 13 is in a (preferably by the adjusting device 50) raised state. The reflector element 41 13 or the floor tile is raised here. 10a again shows a device or a heating box without a bottom heating element 41, while in the device illustrated in FIG. 10b or illustrated heating box a bottom heating element 41 is arranged on the reflector element 41 or a floor tile. The operating device 60 or display device illustrated in FIG. 10c illustrates the method according to the invention.

The heating elements 41 10 or lamps of the two lowest heating zones 8 and 9 (see FIG. 10c) are below the reflector element 41 13 (compare the position of the lowermost two heating elements 41 10 in FIG. 10 a with the position of the base element indicated by the reference symbol S 3 41 13 with respect to the longitudinal direction of the plastic preforms). The heating elements 41 10 of the heating zone 8 and 9 are therefore completely deactivated (and also switched off), which is indicated in FIG. 10c by the reference numeral 76. The arrow P3 illustrates here a possible adjustment of the heating powers of the heating elements 41 10 of the heating box shown in Fig. 10a, in which no bottom heating 41 41 is present, and (just) no heating element 41 10 is turned on. Since the lowermost two heating elements are arranged below the bottom element 41 13 or below the position S3 of the bottom element 41 13 with respect to the longitudinal direction of the plastic preforms, these two are deactivated and can not be marked (by an operator) in this black-filled squares 78 be turned on.

The arrow P4 illustrates a possible setting of the heating powers of the heating elements 41 10 of a heating box shown in Fig. 10b in which the bottom heating element 41 15 is present and this is indicated by a symbol 74 "T", and (even) no heating element 41 10. Here, a heating element 41 10, the lowermost heating element, below the position S2 of the reflector element 41 13 and two further below the position S1 of the bottom heating element 41, 15, are located Top radiator or Bodenheizelementes 41 15 and therefore also deactivated, which is characterized by the symbol 78. The Bodenheizelemente 41 15 are independent of the floor tile position or the position of the reflector element 41 13 always usable, so always activated and can always be switched on or off become.

The Applicant reserves the right to claim all features disclosed in the application documents as essential to the invention, provided that they are novel individually or in combination with respect to the prior art. It is further pointed out that features have also been described in the individual figures, which in themselves can be advantageous. The person skilled in the art immediately recognizes that a particular feature described in one figure can also be advantageous without taking over 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 or in different figures.

LIST OF REFERENCE NUMBERS

1 blowing machine

2 containers

3 preform 10,20,30 transport facilities

40 heating device

41 first heating line

411, 412, 413, 414,

415,416,417 heating modules of the first heating section

4110 more heating elements

4111 counter reflector

4112 back reflector

4113, 4123, 4133 Reflector elements of the heating modules 411,412,413 4115 Floor heating element

4115A, 4115B Positions A and B of the floor heating element

4116 electrical contact

4117 cable guide

4118 electric cable

42 second heating line

421, 422, 423, 424,

425, 426, 427 Heating modules of the second heating section

4213, 4223, 4233 reflector elements of the heating modules 421, 422, 423

43 deflection area

50 adjusting device

51.52 bars

53 straps

54 drive device

60 operating device

62 Arrangement of the heating boxes

64 Heating power of the respective heating zone

70, 72, 74, 78 controls

80 floor reflector detection device

90 preform length detecting means

B floor section

L longitudinal direction of the preforms

P1, P2, P3, P4 arrows

TR1, TR2 transport directions

Claims

claims

Device for heating plastic preforms (3) with a transport device (20), which transports the plastic preforms (3) along a predetermined transport path (TR1, TR2), with a heating device (40) which at least temporarily heats the plastic preforms (3) the heating device (40) at least comprises:

a bottom heating element (41 15) which is suitable and intended to heat a bottom portion (B) of the plastic preforms (3),

a reflector element (41 13) which is mounted in the longitudinal direction (L) of the plastic preforms (3) below the bottom portion (B) of the plastic preforms (3) and reflects thermal radiation on the plastic preforms (3), an adjusting device (50) which is suitable and it is intended to adjust the reflector element (41 13) in the longitudinal direction (L) of the plastic preforms (3),

characterized in that

the bottom heating element (41 15) on the reflector element (41 13) is arranged and / or is adjustable together with this.

Device according to claim 1,

characterized in that

the bottom heating element (41 15) is designed as a radiation element.

Device according to at least one of the preceding claims,

characterized in that

the Bodenheizelement (41 15) is arranged with a defined distance on the reflector element (41 13) or with a defined depth in the reflector element (41 13) is inserted.

Device according to at least one of the preceding claims,

characterized in that the heating device (40) has further heating elements (41 10) which are preferably arranged one above the other in the longitudinal direction (L) of the plastic preforms (3).

5. Device according to the preceding claim,

characterized in that

an electrical contact (41 16) of the bottom heating element (41 15), separated from the electrical contacting of the other heating elements (41 10) is executed.

6. Apparatus according to claim 4 or 5,

characterized in that

an electrical contact (41 16) of the Bodenheizelements (41 15) below the reflector element (41 13) and / or the Bodenheizelements (41 15) extends.

7. Device according to at least one of the preceding claims,

characterized in that

the device can also be operated with the floor heating element (41 15) switched off.

8. Device according to at least one of the preceding claims,

characterized in that

the heat radiation of the heating device (40) is infrared radiation.

9. Device according to at least one of the preceding claims,

characterized in that

the heat radiation from the reflector element (41 13) is reflected in particular to the bottom portion (B) of the plastic preforms (3).

10. A device for heating plastic preforms (3) with a transport device (20) which transports the plastic preforms (3) along a predetermined transport path (TR1, TR2), with a heating device (40) which at least temporarily heats the plastic preforms (3) wherein the heating device (40) comprises at least:

a reflector element (41 13), which is mounted in the longitudinal direction (L) of the plastic preforms (3) below the bottom portion (B) of the plastic preforms (3) and reflects heat radiation to the plastic preforms (3), an adjusting device (50) which is suitable and intended to adjust the reflector element (41 13) in the longitudinal direction (L) of the plastic preforms (3),

at least one heating element (41 10) and preferably a plurality of heating elements (41 10) which are arranged one above the other in the longitudinal direction (L) of the plastic preforms (3),

characterized in that

the device has a control device which is suitable and intended, depending on the position (S3, S2) of the reflector element (41 13) with respect to the longitudinal direction (L) of the plastic preforms (3) at least one heating element (41 10) automatically turn on and / or switch off.

1 1. Device according to the preceding claim,

characterized in that

the control device is suitable and intended to automatically switch on and / or switch off at least one heating element (41 10), which is arranged below the reflector element with respect to the longitudinal direction (L) of the plastic preforms (3).

12. Device according to at least one of the two preceding claims, characterized in that

the heating device (40) has at least one bottom heating element (41 15) which is arranged on the reflector element (41 13) and which is suitable and intended to heat a bottom section (B) of the plastic preforms (3), and the control device is suitable for this purpose and is determined, depending on the

Position (S1) of the Bodenheizelementes (41 15) with respect to the longitudinal direction (L) of the plastic preforms (3) at least one heating element (41 10) automatically turn on and / or off.

13. Device according to at least one of the preceding claims 10-12, characterized in that

the control device automatically switches on and / or off at least one heating element (41 10) in response to a signal transmitted by the adjusting device (50).

14. Device according to at least one of the preceding claims 10-13, characterized in that

the device has a sensor device for detecting a position (S3, S2) of the reflector element (41-12) and / or a position (S1) of the bottom heating element (41-15), and the control device at least one heating element as a function of a position detected by the sensor device (41 10) automatically turns on and / or off.

15. A method for heating plastic preforms (3), in which the Kunststoffvor- molded products (3) by a transport device (20) along a predetermined transport path (TR1, TR2) transported and heated by a heater (40) at least temporarily, said Floor section (B) of the plastic preforms (3) at least by a Bodenheizelement (41 15) is heated and wherein a reflector element (41 13), which in the longitudinal direction (L) of the plastic preforms (3) below the bottom portion (B) of the plastic preforms (3 ), heat radiation to the plastic preforms (3) is reflected, wherein the reflector element (41 13) in the longitudinal direction (L) of the plastic preforms (3) by an adjusting device (50) can be adjusted,

characterized in that

the bottom heating element (41 15) on the reflector element (41 13) is arranged and / or can be adjusted together with this.