AT519501B1 - Apparatus and method for the production of circular or circular-segment-shaped geometries of thermoplastically deformable plastic multi-chamber hollow profiles - Google Patents

Abstract

The invention relates to a device for producing circular or circular-segment geometries of thermoplastically deformable plastic multi-chamber hollow profiles, consisting of a heat source for applying thermal energy to the surface of the hollow profile to be treated, wherein the heat source is surrounded by a Aufheizraum. The heating chamber is designed as an elongated, box-shaped, three-sided closed structure (2), which has two opposite side walls (3) and a bottom (4). On the inside of the side walls (3) and the bottom (4) extending in the longitudinal direction of the structure, elongated and paired infrared emitters (9) are arranged. The infrared radiator (9) are provided in the direction of the interior (R) of the structure with a planar, permeable to infrared radiation cover (5), wherein the remaining, the top side open interior (R) of the temporary recording of the hollow sections to be deformed. In the longitudinal direction of the structure displaceably arranged, for infrared radiation impermeable partition plates (6) are also designed, which cover the infrared rays (9) towards the interior side and / or bottom side to create zones of different degrees of heating of the hollow profile to be deformed.

Description

Description: The invention relates to a device and a method for producing circular or circular segment-shaped geometries of thermoplastic deformable plastic multi-chamber hollow profiles, consisting of a heat source for applying thermal energy to the surface of the plastic multi-chamber hollow profile to be treated, the heat source is surrounded by a heating room according to the preamble of claim 1 and on the process side with a teaching according to claim 12.

The known state of the art in the production of circular or segmental geometries of thermoplastic deformable plastic multi-chamber hollow profiles, for example for use in the production of window or door frames or frames consists in the necessary heating for the relevant Immerse the profile in a glycerin bath and provide the necessary thermal energy in this regard. Typical glycerin bath or oil bath temperatures are around 130 ° C.

If hot air drying ovens are used to heat a hollow plastic profile, a rather long dwell time in the oven has to be accepted, with a large part of the thermal energy already being released into the environment after removal of the part to be bent.

A decisive disadvantage of the use of glycerol-containing liquid or hot air as a medium for contact heating of the multi-chamber hollow profile systems is Aufbzw. Warming of the profiles by flow around the outer contours with oil or glycerin-containing liquid or hot air and thus only indirect heating of the material without a possible influence on a targeted, selective and thus differentiated supply of thermal energy directly from the heat source into or onto the material , In addition, after immersing the hollow profile in an oil or glycerol-containing bath, appropriate cleaning of the profile is to be ensured, which is often difficult or possible with great effort in the case of hollow profiles through trained chambers or undercuts.

In wet bending, the bath must be filled up in a cost-intensive manner due to the technology-related consumption such as evaporation, dripping, washing off the bent parts and the like. After the end of work, the bath temperature drops considerably until the next day, so that the bath has to be heated again in an energy-intensive manner.

From AT 512 718 B1 a method and a device for bending a corner in a profile made of thermoplastic base material is known. It is a basic material for the production of plastic spacer frames for insulating glass windows. According to the teaching there, local heating by means of a heating device up to a softening point is to be realized in order to avoid bulges in the bending area, in particular when bending a polygonal body, with the total width of the bent corner between two in the bending zone of the bending device Calibration surfaces of a calibration device is limited to a target dimension, in particular to the initial width of the bent profile. In relation to the heating, the inside and the outside of the profile are heated by the heating device to different softening temperatures.

In the heating device according to AT 512 718 B1, the heating time can be preselected differently via the heating power on the inside and the outside of the profile.

[0008] The heating device can comprise at least one infrared radiation element.

For the production of polygonal spacer frames with three or more corner areas, made of an elastically-plastically deformable plastic material, a heating device is provided according to DE 20 2015 105 146 U1, which for heating the corresponding profile or parts thereof to a predetermined temperature near the melting point the material of the profile is used.

/8th

AT 519 501 B1 2019-04-15 Austrian

Patent Office [0010] With regard to the heating processes or heating devices used there, reference is made to induction, resistance, ultrasound, infrared or high-frequency systems. In the case of induction or resistance heating, heating elements are embedded in the respective plastic profile. Accordingly, the heating effect is achieved directly in or on the material of the profile and the heat is transferred directly to the plastic of the profile. The heating elements can extend sectorally, that is to say in sections, over the length of the profile, or else can be embedded throughout the profile. By using pyrometers and using a control circuit, temperature profiles can be simulated and controlled, depending on the choice of the plastic used for the production of the profile and other sizes.

From the foregoing, it is an object of the invention to provide a further developed method and an associated device for the production of circular or circular segment-shaped geometries of thermoplastically deformable plastic multi-chamber hollow profiles, which makes it possible to produce completely different hollow profiles in an effective, energy-saving manner , especially for window and / or door construction. The disadvantages of the previous heating in a liquid bath with the consequent necessary cleaning steps of the profile are to be eliminated, as is the likewise energy-intensive heating using hot air, which also leads to the environment being unnecessarily subject to extreme heating, which results in poorer working conditions.

The object of the invention is achieved with a device according to the combination of features according to claim 1 and with a method according to the teaching according to claim 12.

It has surprisingly been found that through the device according to the invention with a heating space as an elongated, box-shaped structure closed on three sides, rapid, sufficient and targeted heating through to the softening and bending temperature of completely different hollow chamber profiles can take place, while simultaneously Monitoring the surface temperature of the profile to be deformed can be avoided.

Due to the invention used bulkheads, which are displaceable based on the longitudinal extent of the structure and the receiving space, depending on the desired circular segment or arc shape, a setting of colder, non-deformable sections can be selected, so that in a single bending process After the complete profile has been heated, several, also different, bending zones can be implemented, between which straight-line sections extend.

Depending on the dimensions of the free interior of the structure and the sizes of the profiles to be deformed, several profiles can be heated simultaneously and successively subjected to the desired bending step. The arrangement of the infrared radiators ensures that, despite the open top of the structure, which is advantageous for handling, uniform heating of the hollow profiles is ensured.

Flat and flat covers which are permeable to IR radiation, in particular with regard to the bottom and parts of the side walls of the structure, enable the hollow profile introduced to be laid over a large area and at the same time ensure homogenization of the infrared radiation, so that hot spots cannot occur. In contrast to grid-like or net-like contact surfaces for the hollow chamber profiles, there is also no risk of the profiles being damaged on the surface.

In the embodiments of the invention, pyrometers used can be pivoted in order to be able to direct the same to the respective profile for detecting the surface temperature.

It is also possible to design at least some of the infrared radiators, which are preferably arranged in pairs, in a manner that is adjustable, in particular height-adjustable.

The device according to the invention thus comprises a heating room in the form of a long

2.8

AT 519 501 B1 2019-04-15 Austrian

Patent-office stretched, box-shaped structure closed on three sides.

[0020] This structure has two opposite side walls and a bottom.

Inside the side walls and the bottom extending, elongated and paired infrared radiators are arranged in the longitudinal direction of the structure.

The infrared radiators are provided in the direction of the interior of the structure with a flat cover that is permeable to infrared radiation, the remaining, open-top interior serving to temporarily accommodate the plastic multi-chamber hollow profiles to be deformed.

The radiation-permeable cover is preferably made of a quartz glass or borosilicate glass.

In the longitudinal direction of the structure, the previously mentioned, infrared radiation-impermeable bulkhead plates are arranged displaceably. The partition plates cover the infrared emitters towards the interior on the side and / or bottom, in order to create the desired zones of varying degrees of heating of the plastic multi-chamber hollow profile to be deformed.

The heating chamber is preferably double-walled, with fans being provided at least on the bottom for cooling and for avoiding local overheating. The double wall also ensures that the outside surface temperature of the device does not exceed a maximum temperature in order not to endanger the worker or operator.

The aforementioned cover made of glass, in particular quartz glass or borosilicate glass, is floating to avoid thermally induced stresses.

At least the infrared radiators formed on the side walls are rod-shaped and adjustable, in particular height-adjustable.

The surface of the side walls and / or the bottom is designed to reflect infrared radiation in order to increase the thermal efficiency of the device.

In a preferred embodiment, the structure has an essentially U-shape, the connecting leg being implemented as the bottom.

The end faces of the structure are designed to be open for introducing longer hollow profiles or at least open on one side.

As mentioned, the structure has one or more pyrometers for detecting the surface temperature of the hollow profile introduced. The pyrometer or pyrometers are connected to a control unit in order to specify the electrical energy supplied to the infrared radiators, with the result of an increase in efficiency when operating the device and at the same time avoiding impermissibly high surface temperatures of the plastic materials to be deformed.

A radiation-homogenizing distance is provided between the cover and the infrared radiators.

In the area of the interior open at the top there is at least one additional pair of elongated infrared emitters in front of the opposite side walls, the main radiation direction of which is oriented toward the interior, in particular towards the center of the interior, and thus at a corresponding angle.

In the method according to the invention for producing circular or circular segment-shaped geometries of thermoplastically deformable plastic multi-chamber hollow profiles, the hollow profile workpiece to be deformed is first introduced into the interior of the structure. For certain hollow profiles, it has proven to be advantageous to insert, in particular to insert, filling tools that are matched to the profile into sections of the hollow profile. These filling tools preferably consist of an elastic one, from the temperature 3/8

AT 519 501 B1 2019-04-15 Austrian

Patent Office

Bendable material that does not affect the effect, fills the cavity and follows the bending process due to its elasticity. This prevents undesired buckling of sections of the hollow profile due to compression processes.

After the hollow profile has been introduced into the interior, the partition plates are then adjusted by shifting with regard to the desired heating zone or with regard to the necessary colder sections.

This is followed by an activation of the infrared radiator after selection of the maximum surface temperature based on the hollow profile used. The result is an immediate, direct heating of the hollow profile with independent regulation of the infrared radiators when the surface temperature is reached. After the heated hollow profile has been removed, it can be subjected to the bending process using a bending tool with the aid of a suitable bending shape.

The invention will be explained below using an exemplary embodiment and with the aid of a figure.

The figure shows a cross section of the device according to the invention with a receiving space, which starts from a structure with a substantially U-shape, the connecting leg of the U forming the bottom of the device and the open top or front faces to be opened deforming workpiece, namely a plastic multi-chamber hollow profile, can be introduced.

The device according to the schematic diagram of the figure of the embodiment is based on a frame 1, which comprises several feet. The device further comprises a module housing 2.

The module housing 2 is designed as a heating space in the form of an elongated, box-shaped structure closed on three sides.

[0041] This structure comprises two opposite side walls 3 and a bottom 4.

On the inside of the side walls 3 there are elongated and paired infrared emitters E3 and E4 as well as E5 and E6.

In the floor area there are further paired infrared emitters E8 and E7.

The infrared emitters E3, E4, E5, E6 and E8 and E7 are provided in the direction of the interior R of the structure with a flat cover 5, preferably made of glass, which is transparent to infrared radiation.

The remaining interior R, which is open at the top, serves to accommodate the plastic multi-chamber hollow profile to be deformed (not shown).

In the longitudinal direction of the structure displaceably arranged, for infrared radiation barrier plates 6 are formed.

The bulkheads 6 are guided in a slide rail arrangement 7 and are displaceable in the longitudinal direction (arrow representations).

Corresponding actuating handles 8 enable the aforementioned longitudinal displacement of the partition plates 6.

The bulkheads 6 can extend not only in front of the lateral infrared radiators 9, but also the infrared radiators E7 and E8 arranged on the bottom, adjustable.

The module housing 2 is double-walled, with fans 10 being provided at least on the bottom side for cooling and for avoiding local overheating.

The infrared emitters E4 and E6 or E3 and E5 executed on the side walls

4.8

AT 519 501 B1 2019-04-15 Austrian

As symbolized by the further arrow display, the patent office can be made height-adjustable.

The surface of the side walls 3 and / or the bottom 4 can be made reflective for infrared radiation.

As can be seen, the structure shown comprising the side walls 3 and the bottom 4 has a substantially U-shape, the connecting leg of the U being designed as a bottom 4.

In addition, there is the possibility that pyrometers 11 are provided in order to determine the surface temperature of the hollow chamber profile introduced in the interior R and to control the infrared emitters 9 via a suitable control unit.

Thermal mudguards 12 on the module housing 2 serve as protection against contact and to increase occupational safety.

At least one pair of additional elongated IR radiators E2 and E1, the main radiation direction of which is oriented toward the center of the interior R, are arranged in front of the opposite side walls 3 in the region of the interior R, which is open at the top. The combination of the arrangement of the infrared emitters E1 to E8 ensures uniform heating of the hollow profile introduced in each case.

The exemplary dimensions in the illustration according to the figure show the available sizes of the interior R and show that profiles with conventional cross-sectional dimensions for window and door construction can be heated with the device according to the invention and then subjected to the necessary bending process ,

With the help of the movable in the longitudinal direction of the device bulkheads 6, each extending only over a partial longitudinal section, a targeted thermal isolation of the elongated plastic multi-chamber hollow profile can be carried out and a precise delimitation of those areas that are made with infrared Apply energy and heat up in this regard. In a realized embodiment of the device according to the invention, the heated length is approximately 2 m. The exemplary angle of the infrared emitters E1 and E2 with respect to the center of the interior R is essentially 135 °.

The respective position of the partition plates with respect to the longitudinal extent of the device can be fixed by means of a clamping device and secured against undesired displacement.

5.8

AT 519 501 B1 2019-04-15 Austrian

Patent Office

Claims (12)

claims 1. Device for producing circular or segmental geometries of thermoplastic malleable plastic multi-chamber hollow profiles, consisting of a heat source for applying thermal energy to the surface of the plastic multi-chamber hollow profile to be treated, the heat source being surrounded by a heating chamber, thereby characterized in that the heating chamber is designed as an elongated, box-shaped structure (2) closed on three sides, which has two opposite side walls (3) and a bottom (4), on the inside of the side walls (3) and the bottom (4) in the longitudinal direction of the Formed, elongated and paired infrared emitters (9) are arranged, the infrared emitters (9) in the direction of the interior (R) of the structure are provided with a flat cover (5) which is transparent to infrared radiation, the remaining, interior open at the top (R) of the temporary receiving of the to be deformed The plastic multi-chamber hollow profiles are used, as well as bulkheads (6) which are slidably arranged in the longitudinal direction of the structure and which are impermeable to infrared radiation and which cover the infrared radiators (9) laterally and / or on the floor in the direction of the interior in order to heat up zones of different intensities to create plastic multi-chamber hollow profile. 2. Device according to claim 1, characterized in that the heating space is double-walled, with fans (10) at least on the bottom side being provided for cooling and for avoiding local overheating. 3. Device according to claim 1 or 2, characterized in that the cover (5) consists of glass, in particular quartz glass or borosilicate glass, which is floating to avoid thermally induced stresses. 4. Device according to one of the preceding claims, characterized in that at least the infrared emitters (E3; E4; E5; E6) formed on the side walls (3) are designed to be adjustable, in particular height-adjustable. 5. Device according to one of the preceding claims, characterized in that the surface of the side walls (3) and / or the bottom (4) is designed to reflect infrared radiation. 6. Device according to one of the preceding claims, characterized in that the structure has a substantially U-shape in cross section, wherein the connecting leg is designed as a bottom (4). 7. The device according to claim 6, characterized in that the end faces of the structure for opening longer hollow profiles are designed to be open or at least open on one side. 8. Device according to one of the preceding claims, characterized in that the structure has pyrometer (11) for detecting the surface temperature of the hollow profile introduced. 9. The device according to claim 8, characterized in that the pyrometers (11) are connected to a control unit in order to specify the energy supplied to the infrared radiators (9). 10. Device according to one of the preceding claims, characterized in that a radiation-homogenizing distance is set between the cover (5) and the IR emitters (9). 11. The device according to one of the preceding claims, characterized in that in the region of the interior open at the top (R) in front of the opposite side walls in each case at least one additional pair of elongated infrared radiators (E1; E2) is arranged, the main radiation direction to the center of the interior ( R) is oriented. 6.8 AT 519 501 B1 2019-04-15 Austrian Patent Office 12. A method for producing circular or segmental geometries of thermoplastic mouldable plastic multi-chamber hollow profiles, comprising a heat source for applying thermal energy to the surface of the hollow profile to be treated, wherein the heat source is surrounded by a heating space according to any one of the preceding claims following steps: Introducing the plastic multi-chamber hollow profile to be deformed into the interior of the structure and, if appropriate, inserting filling tools into selected sections of the hollow profile; Adjusting the bulkhead plates with regard to desired colder sections of the plastic multi-chamber hollow profile to be deformed; Activate the infrared emitters after selecting the maximum surface temperature of the respective plastic multi-chamber hollow profile; Immediate, direct heating of the plastic multi-chamber hollow profile with independent regulation of the infrared emitters when the surface temperature is reached; and Removing the heated hollow profile and bending using a bending tool and / or bending device.