Abstract
The invention relates to a plastic-welding device for connecting a first, thin-walled plastic part to a second plastic part in a planar manner. The device includes a hand-held mounting aid and a welding head that can be held in a retainer of a hand soldering iron; wherein the welding head has a main body and at least one welding tip arranged on the main body. The mounting aid has at least one spacer, which can be placed onto the thin-walled plastic part by means of an underside of the at least one spacer and on the surface of which the main body of the welding head can be supported. The spacer is designed so that, when the main body is supported on the at least one spacer, a depth of penetration of the welding tip into the plastic parts to be connected is limited to a predetermined maximum value.
Claims
1. A welding head for producing plastic rivet joints, the welding head in the form of a soldering iron attachment or soldering iron insert, wherein the welding head comprises a base body (21) with a bottom end face having an axially raised circumferential rim (17) and a welding tip (18) disposed at a center.
2. The welding head according to claim 1, wherein the welding tip (18) is conical.
3. The welding head according to claim 1, wherein the bottom end face of the base body (21) comprises a recess (19) surrounding the axis between the welding tip (18) and the rim (17).
4. The welding head according to claim 1, wherein the base body (21) is cylindrical or rectangular.
5. A welding head for welding two plastic parts together, the welding head in the form of a soldering iron attachment or soldering iron insert and comprising a base body (21) with a slanted bottom end face (23), the slanted bottom end face (23) comprising a welding tip (26) and an opening (25) of a bore (24), the bore (24) extending along a side of the base body to the slanted bottom end face (23) and adapted to introduce plastic for welding.
6. The welding head according to claim 5, wherein the slanted bottom end face (23) of the base body (21) is horseshoe-shaped.
7. The welding head according to claim 6, wherein the bore opening (25) on the slanted bottom end face (23) of the base body (21) is disposed concentrically or eccentrically to the longitudinal axis of the base body.
8. The welding head according to claim 7, wherein the welding tip (26) is V-shaped.
9. The welding head according to claim 8, wherein the welding tip (26) comprises a sword-shaped extension (27) for welding thicker plastic parts or for welding on one side.
10. The welding head according to claim 8, wherein the slanted bottom end face (23) of the base body (21) is bilaterally parallel and flush with the sides of the welding tip (26), and wherein the area of the bore opening (25) is flattened.
11. The welding head according to claim 5, wherein the bore (24) is a drilled bore.
12. The welding head according to claim 5, wherein the base body (21) is cylindrical.
Description
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0024] The following discussion describes the invention in more detail based on exemplary embodiments that relate to the drawing.
[0025] FIG. 1 is a perspective view of a welding head;
[0026] FIG. 2 is a perspective view of an embodiment of a handheld installation aid;
[0027] FIG. 3 is a front view of an installation aid with inserted welding head;
[0028] FIG. 4 is a perspective view of a hand soldering iron with inserted welding head;
[0029] FIG. 5 is a perspective view of a cooling die with cooling body;
[0030] FIG. 6 is perspective view of a centering element;
[0031] FIG. 7 is a perspective view of an installation aid of the embodiment in FIG. 2 with inserted welding head, and a first and second plastic part;
[0032] FIG. 8 is a front view of the handheld plastic welding device in FIG. 7;
[0033] FIG. 9 is a perspective view of another embodiment of a handheld installation aid with inserted welding head;
[0034] FIG. 10 is a perspective view of a welding head for plastic riveting;
[0035] FIG. 11a is a perspective view of one variant of a welding head to join planar plastic parts;
[0036] FIG. 11b is a perspective view of one variant of a welding head to join planar plastic parts;
[0037] FIG. 11c is a perspective view of one variant of a welding head to join planar plastic parts;
[0038] FIG. 12a is perspective view of a rectangular welding head; and
[0039] FIG. 12b is a perspective view of the rectangular welding head shown in FIG. 12a.
DETAILED DESCRIPTION OF THE INVENTION
[0040] FIGS. 1 and 2 depicts a welding head 2 (FIG. 1) and an installation aid 1 (FIG. 2) of a handheld plastic welding device for the planar joining of a first, thin-walled plastic part 6 to a second plastic part.
[0041] FIG. 1 is a perspective view of welding head 2, comprising a plate-shaped base body 3 that includes a plurality (eight in FIG. 1) of welding tips 4 that are arranged in two longitudinal rows. Other arrangements and a different number of welding tips are also possible. A cylindrical rod 10 to be received in a hand soldering iron 7 is provided on the side of plate-shaped rectangular base body 3 opposite of the welding tips 4. The same welding head 2, inserted in hand soldering iron 7, is also depicted in FIG. 4 in a view of the bottom side of base body 3.
[0042] FIG. 2 is a perspective view of an embodiment of a handheld installation aid 1. Installation aid 1 has a handle 12 comprising a central attachment body in the form of an attachment plate 13. Two spacers 5 disposed a certain distance apart are removably attached, e.g., by means of a screw connection, to the attachment plate 13 so as to be flush with the bottom edge. Spacers 5 are in the form of protruding rectangular bodies and include a flange 11 on each side facing the other spacer. The thickness of the flange together with the length of welding tips 4 determine the maximum penetration depth of welding tips 4 into the plastic parts to be joined.
[0043] In order to change the penetration depth dependent on the thickness of thin-walled first plastic part 14, using identical welding head 2, it is possible to simply replace removably attached spacers 5 with spacers 5 having flange 11 of different thickness.
[0044] Base body 3 of welding head 2 in the depicted example also has a flange 15 on the rim that is complementary to flange 11 of spacer 5 so as to enhance the stability of welding head 2 relative to installation aid 1.
[0045] FIG. 3 is a front view of installation aid 1 with inserted welding head 2 of FIGS. 1 and 2. This reveals how welding tips 4 protrude below installation aid 1, and specifically in the region in which they are pressed into the two plastic parts during welding. This is also illustrated in FIG. 7 (perspective view) and FIG. 8 (front view), whereby these figures show the thin-walled first plastic part 6 and second plastic part 20. During welding, welding tips 4 are pressed through thin-walled first plastic part 6 into second plastic part 20 such that, after hardening, the molten plastic of the two plastic parts forms a strong welded joint. FIGS. 7 and 8 furthermore reveal that first plastic part 6 can be held by both spacers 5 resting on plastic part 6. Spacers 5 perform the function of holding the plastic parts and simultaneously ensuring an optimal penetration depth for welding tips 4.
[0046] FIG. 5 is a perspective view of a cooling die 8 with cooling body 9. In terms of its longitudinal extension, this is selected so as to be slightly smaller than the base body, thereby enabling it to be pressed between spacers 5 to effect cooling and effect pressing the material together onto the molten plastic. Cooling body 9 has a planar bottom side.
[0047] FIG. 6 is a perspective view of a centering element 14 used to align the two plastic parts with each other when joining plastic parts having through openings, e.g., a retainer of a distance sensor on the inside of a bumper or of the plastic covering of a bumper. FIG. 7 depicts a centering element 14 that is inserted into an opening of first plastic part 6. Centering element 14 includes a cylinder, the two sides of which have different diameters.
[0048] FIG. 9 is a perspective view of another embodiment of handheld installation aid 1 with inserted welding head 2. Unlike the installation aid in FIG. 2, installation aid 1 in FIG. 9 has a brace 16 attached to handle 12 as the central attachment body. Two angle brackets acting as spacers 5 are removably attached to the brace, e.g., by means of a screw connection. The maximum penetration depth of welding tips 4 into the plastic is determined by the thickness of the angle brackets.
[0049] FIG. 10 is a perspective view of a welding head for producing plastic rivet joints. The welding head has a cylindrical base body and is preferably in the form of a soldering iron attachment or soldering iron insert. The cylindrical base body has on the bottom side an axially raised circumferential rim 17 and a conical tip 18 at the center, thereby creating a circumferential valley 19 between tip 18 and rim 17.
[0050] FIG. 11 is a perspective view of two variants of a welding head for welding two plastic parts. FIG. 11(a) provides a perspective view from above of the welding head and the plastic parts 28, 29 to be welded (the perspective is identical for both variants.) FIGS. 11(b) and 11(c) provide a perspective view from below of the bottom side of the welding head.
[0051] The welding head has a cylindrical base body 21 including a bottom side 23 that is tilted relative to the soldering iron retainer 22. Based body 21 with a tilted bottom side 23 has a horseshoe-like shape (FIG. 11(a)). A V groove is shown in the joining region of both plastic parts 28, 29, which groove is created by V-shaped tip 26 of the welding head and is filled with supplied plastic (not shown). The supplied plastic and the rim section of both plastic parts 28, 29 create a strong durable welded joint.
[0052] A drilled hole 24 for introducing the plastic required for welding runs along the side of cylindrical base body 21 up to the tilted bottom side 23. Opening 25 of the drilled hole 24 is disposed eccentrically. The base body has a V-shaped tip 26 in the welding direction in front of opening 25 on the bottom side 23, as shown in FIGS. 11(b) and 11(c). During the welding process, V-shaped tip 26 melts a V groove between the two plastic parts, which groove is subsequently filled with the supplied plastic. This creates an especially clean and strong joint of the two plastic parts. V-shaped tip 26 can also include a sword-shaped extension 27, as shown in FIG. 1 (c), for welding thicker plastic parts together.
[0053] Instead of the cylinder, the base body can be of rectangular shape, and the through hole for introducing the plastic can be in the form of a slot. The welding head can have an axially running groove at the front as a guide for moving precisely along a crack.
[0054] FIG. 12 is a perspective view of a welding head that, unlike the welding heads in FIG. 11, has a rectangular base body. FIG. 12(a) is a perspective view of the welding head from above, while FIG. 12(b) is a perspective view from below. A slot 31 can be provided instead of the drilled hole to deliver the plastic. V-shaped tip 26 can similarly be provided on the bottom side of the rectangular base body 30. In addition, the bottom side in the welding direction can have a cutout 32 after slot 31 running up to the rim for applying a plastic coating to the surface of both parts 28, 29 to be welded.
[0055] The welding heads in FIGS. 11 and 12 can have an axially running groove in welding direction at the front as a guide 33 for moving precisely along a crack, as shown in FIG. 11(b).
