TUBE END DETECTION

Abstract

A method, and an apparatus associated therewith, for detecting plastic tube ends clamped in a butt welding machine, the plastic tube ends being planed by means of a plane, which can be introduced between the plastic tube ends, and subsequently being heated by means of a heating mirror, which can be introduced between the plastic tube ends, and the plastic tube ends are welded together after removal of the heating mirror, the plane and/or the heating mirror being tilted in between the plastic tube ends by means of a controlled movement, wherein detection or sensing of the plastic tube ends during the controlled movement of tilting in the plane and/or the heating mirror is carried out by means of at least one sensor arranged on the plane and/or on the heating mirror.

Claims

1. A method for detecting plastic tube ends clamped in a butt welding machine, the plastic tube ends being planed by means of a plane, which can be introduced between the plastic tube ends, and subsequently being heated by means of a heating mirror, which can be introduced between the plastic tube ends, and the plastic tube ends are welded together after removal of the heating mirror, the plane and/or the heating mirror being tilted in between the plastic tube ends by means of a controlled movement, characterized in that detection or sensing of the plastic tube ends during the controlled movement of tilting in the plane and/or the heating mirror is carried out by means of at least one sensor arranged on the plane and/or on the heating mirror.

2. The method according to claim 1, wherein the two opposing plastic tube ends are respectively detected or sensed by means of a separate sensor.

3. The method according to claim 1, wherein the detection or sensing of the plastic tube ends is carried out by means of an optical sensor.

4. The method according to claim 1, wherein the detection or sensing of the plastic tube ends is carried out by means of a laser.

5. The method according to claim 1, wherein the detection or sensing of the plastic tube ends is carried out by means of a capacitive sensor.

6. The method according to claim 1, wherein the detection or sensing of the plastic tube ends is carried out contactlessly.

7. The method according to claim 1, wherein a tube dimension is determined by means of a sensor.

8. Method according to claim 1, wherein a tube material is determined by means of a sensor.

9. Apparatus for the butt welding of plastic tube ends, in particular by the method according to claim 1, containing two clamping points arranged in a coaxial position, the clamping points holding the plastic tube ends, a plane, the plane being capable of being introduced between the plastic tube ends in order to plane the plastic tube ends, and a heating mirror for subsequent heating of the plastic tube ends, the heating mirror being capable of being introduced between the plastic tube ends, and the plastic tube ends being welded together after removal of the heating mirror by moving the clamping points toward one another, the plane and/or the heating mirror being tilted in between the plastic tube ends by means of a controlled movement, wherein at least one sensor for detection or sensing of the plastic tube ends during the controlled movement of tilting in the plane and/or the heating mirror is arranged on the plane and/or on the heating mirror.

10. Apparatus according to claim 9, wherein the movement processes preferably all take place while being controlled, or are regulated by a controller of the apparatus.

11. A method of welding tube ends together, comprising: entering welding parameters into a controller; clamping first and second tubes so that respective ends of the tubes are aligned but spaced from each other; affixing a sensor to a tool; rotating the tool along with the sensor through the space between the tube ends and using the sensor to detect characteristics of the tubes; comparing the entered welding parameters in the controller with the characteristics detected by the sensor and, if the comparison is acceptable, continuing to: butting the ends of the tubes to weld them together.

12. The method of claim 11 wherein the tool is a plane or a heated mirror.

Description

DRAWINGS

[0026] An exemplary embodiment of the invention will be described with the aid of the figure, the invention not being restricted only to the exemplary embodiment.

[0027] FIG. 1 shows a schematic end view of an apparatus according to the invention for carrying out the method according to the invention;

[0028] FIG. 2 shows a perspective view of the apparatus shown in FIG. 1 with the plane outside of the tube ends;

[0029] FIG. 3 shows a side view of the apparatus with the plane in contact with the tube ends;

[0030] FIG. 4 shows a side view of the apparatus with a heated mirror between the tube ends; and

[0031] FIG. 5 shows the heated tube ends butted together.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] FIG. 1 shows a schematic representation of the apparatus 1 according to the invention for carrying out the method according to the invention.

[0033] In the clamping point 2, one of the tube ends 3 to be welded to one another can be seen, the other clamping point with the clamped tube end lying in front of the view and therefore not being visible.

[0034] In the embodiment represented, the sensor 4 is arranged on the plane 5. By the controlled tilting-in of the plane 5, as a result of which that there is a defined tilting movement in relation to distance and speed, the sensor 4 moves constantly along a predetermined curve 6, or a radius.

[0035] At the level of the tube end 3, the sensor 4 perceives that there is a tube there and can, by measuring the duration for which the sensor 4 perceives the tube and the speed of the tilting movement and the predetermined distance, therefore determine which tube or tube dimension is clamped. The required welding parameters, which have been stored in relation to dimension and in relation to material in the controller, can therefore be allocated.

[0036] As an alternative, the sensor may also be arranged on the heating mirror.

[0037] FIG. 2 shows the components of the apparatus 1 in perspective view, basically at their beginning position. The tubes 8 and 9 are held in aligned but spaced apart condition by clamps. Here, tube 8 is held by clamps 2a and 2b. Tube 9 is held by clamp 2a′ and 2b′. The planing device or simply the plane 5 is shown in position outside of the longitudinal axis of the tubes. The sensor 4 is affixed to part of the plane 5; more particularly, the sensor 4 is affixed to the outer circumstance of plane 5.

[0038] Turning now to FIGS. 1-2, as well as FIG. 3, the plane 5 is tilted or rotated along the arc or curve 6 through the space between the ends of the tubes 8 and 9 as shown in FIG. 3. As the plane 5 is rotated through curve 6, the sensor 4 senses information about the ends of the tubes 8 and 9. As noted above, this information detected by sensor 4 can be a wide variety characteristics of the tubes such as the thickness of the walls of the tube ends, the material in which the tubes are made, the color of the tubes or the hardness of the tubes.

[0039] Prior to the beginning of the butt welding process, an operator enters data into controller 10 to control the parameters of the butt welding process. These parameters can vary as known to a person of ordinary skill in the art. Generally, the parameters include time, temperature, pressure and other factors that control the butt welding process. These parameters are stored in controller 10 and compared with the parameters sensed by sensor 4 that are communicated to the controller 10. If the parameters match or are acceptable, the butt welding process can continue. Otherwise, the controller 10 detects an error. Typically, the error is due to incorrect parameters being input to the controller 10 prior to the butt welding process. If an error is detected, suitable warning is given to the operator so that the operator can enter the proper parameters for the particular tubes that are to be butt welded together.

[0040] Assuming no error is detected, the butt welding process continues. The plane 5 is circulated to machine the tube ends. Then the plane is moved out and the ends of tubes 8 and 9 are heated by a suitable heating mechanism shown in FIG. 4. Here, the mechanism is a heated mirror 11. The sensor can be placed on the heater mirror instead of the plane 5. This is illustrated by the numeral 4′ in FIG. 4. In both cases, the sensor 4 or 4′ passes adjacent to the ends of the tubes 8 and 9 during tilting of the plane 5 or heated mirror 11 into the space between the tubes.

[0041] Finally, the heated tubes are pressed together under the proper pressure determined by the program parameters in controller 10 as shown in FIG. 5 where the two tube ends are pressed together.