DE29713474U1 - Manual welding machine - Google Patents

Description

Hand cutter FIELD OF APPLICATION AND STATE OF THE ART

The invention relates to a hand-held welding device for connecting adjacent surfaces of a floor covering, in particular for welding a plastic covering, by means of melting material for heating and introducing it into a joint between the surfaces, wherein the melting material is guided via a feed of a nozzle of the hand-held welding device and can be heated therein.

When laying floor coverings over large areas, for example plastic coverings in sports halls or linoleum coverings in large rooms, the coverings are laid in strips and attached to the floor using special adhesives. The edges of the strips are laid butt-to-butt. In order to prevent the edges of the strips from coming off the floor due to strong point loads, they are connected to one another in addition to being glued to the subfloor. This connection is usually made by welding, whereby a suitable melting material is introduced into an existing or to-be-created joint between the strips.

Hand-held welding devices are known that are constructed like a hot air device and have a special nozzle that

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both the hot air flow is concentrated precisely and the melting material is fed to this point. The melting material is usually in the form of a long cord made of plastic.

To ensure that work can be carried out quickly and evenly, the cord-shaped melting material is very long. As a result, a large amount of melting material lies around on the floor covering being worked on during work. On the one hand, this affects people who are working on laying the floor covering or are busy with other activities. The joints often have to be worked on over a large length, so that it can happen that the melting material stretches along the entire joint being worked on on the floor.

Another disadvantage is that the processing process can be disrupted by the melting material becoming blocked. This can happen, for example, if someone steps on melting material lying around or if it gets caught on objects that have been left lying around, such as a toolbox 0.

Another disadvantage is that the melting material becomes contaminated by dirt particles on the floor covering that can stick to it. This can make it difficult to guide the melting material in the nozzle and also make the welding of the joint itself contaminated. This can lead to the weld not having sufficient adhesion and producing an unsatisfactory result. In these places, the floor covering is then not sufficiently protected against the edges coming off.

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TASK AND SOLUTION

It is considered the object of the invention to create a hand-held welding device that avoids the above-mentioned disadvantages of the prior art, is comfortable and easy to operate and ensures a reliable welding process.

This task is solved by providing a holder for the melting material on the hand-held welding device. This avoids contact between the melting material and the floor. Furthermore, the melting material is neatly stored and in the immediate vicinity of the processing location. This means that relatively large quantities of melting material can be carried along, making it possible to work along a very long joint.

The receiving device is advantageously arranged on the hand welding device in such a way that it is located with the melting material essentially above the hand welding device. This means that it has the greatest distance from a dirty floor, enables particularly convenient feeding from above into the nozzle and prevents the hand welding device from tipping to the side due to excess weight on one of the sides.

The receiving device preferably has a support frame, in particular made of a band-like material. This design enables simple production by punching out a sheet of suitable material, such as stainless steel, and bending it into the desired shape. The receiving device and support frame can be made in one piece.

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A particularly simple and secure fastening option is achieved if the mounting device is attached to the housing of the hand-held welding device at least partially around the outer circumference of the housing. The mounting device can be attached to the housing of the hand-held welding device at least partially via recesses in the mounting device, into which projections or the like provided on the housing engage. This creates the possibility, for example, of fastening in the manner of a band clamp, which is attached with a long screw or the like. The recesses prevent the fastening device from being able to rotate around the longitudinal axis of the hand-held welding device.

The invention can be implemented particularly favorably if the melting material is in the form of a cord and is wound onto a winding core, in particular a drum or the like. In this way, a large amount of melting material can be made available in a compact and easily removable manner.

For this purpose, it is advantageous if the holding device has an axle, which is in particular held on the support frame, which carries the winding core carrying the melting material and is rotatably mounted. The axle can be inserted in the middle or from one side. It is possible to attach the winding core to the axle without removing the holding device from the hand welding device. Changing the winding core with the melting material can thus be carried out very easily and quickly. Metal is preferably used as the material for the axle, especially stainless steel or steel with a treated surface.

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In a preferred embodiment of the invention, fixing means are provided on the axle for fixing and centering the winding core. This ensures that the winding core is securely seated and well guided on the axle for optimized feeding of melting material to the nozzle of the hand-held welding device. It is also possible to use winding cores of different widths and different bore diameters. To better attach the fixing means to the axle, the axle can be flattened on one side so that clamping screws or the like can be held firmly. They can be made of a sturdy plastic to reduce the weight.

The fixing means can be at least partially conical, rotationally symmetrical riders that can be plugged onto the axis and fastened to it.

Advantageously, braking means for the axle are provided on the receiving device, in particular on the support frame, which brake rotation of the axle with a braking force adjustment device that can be set by a user. 0 This prevents the melting material from unintentionally unwinding or rewinding.

The braking means can essentially consist of a preferably conical spiral spring which is pushed onto a threaded end of the axle which protrudes above the receiving device and which is pressed against a disc by a nut or the like at the end of the axle. The braking force which is created by friction either on the contact surface of the spiral spring with the disc or with the nut can be determined by the position of the nut and the resulting compression of the

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Spiral spring can be adjusted. The nut together with the thread forms the adjustment device.

The nozzle preferably has a melting chamber that is open downwards towards the floor covering and through which the melting material can be introduced into the joint, whereby a hot air flow from the hand welding device in this melting chamber is directed at the melting material and the floor covering in the area of the joint. Both the melting chamber and the feed of the melting material and the nozzle pipe for the hot air flow can be designed in such a way that the melting material is melted either before it is introduced into the joint, during it or after it is introduced. It is considered advantageous if the two feeds run towards each other at an acute angle, for example around 30°, so that the hot air flow can heat the melting material over a larger area. In order to enable complex designs of the nozzle and the melting chamber, it is preferably made of metal using a casting process. Aluminum or steel are suitable for this.

The supply of the melting material can be adapted to its cross-sectional shape.

For this purpose, the nozzle can have a small opening or recess in the path of the hot air flow just before the melting chamber or adjacent to it, through which part of the hot air flow can be directed into an area of the joint that is just before the area into which the melting material is introduced. This preheating of the joint achieves a better connection with the melting material. Since the underside of the nozzle slides over the floor, it is smooth on its underside apart from recesses. In order to be able to work on bends or the like, it can be rounded in the opposite direction to the working direction.

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In a preferred embodiment of the invention, the hand-held welding device has a guide device by means of which it can be guided precisely along the joint, whereby the guide device at least partially supports the hand-held welding device. For this purpose, it can contain a narrow roller or the like with a tapered edge that is guided in the joint. Additional rollers or the like can be provided to support the hand-held welding device, but are not absolutely necessary.

The guide device can advantageously be attached or mounted on the mounting device. It can consist of a rod in the shape of a triangle that is attached at two corners and has the guide roller on its third corner. The guide device can also be attached to the housing of the hand-held welding device in a similar way to the mounting device. This means that its use is independent of the mounting device.

A significant advantage of the hand-held welding device according to the invention is that the described design options of the invention retain the ease of handling of a hand-held welding device. A user can control the weld seam and, above all, its formation very well, preferably by partially guiding it by hand.

These and other features emerge not only from the claims but also from the description and the drawings, whereby the individual features can be implemented individually or in combination in the form of sub-combinations in an embodiment of the invention and in other fields and can represent advantageous and protectable embodiments for which protection is claimed here.

0 The division of the application into individual sections and

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Subheadings do not limit the general validity of the statements made under them.

KDRZ DESCRIPTION OF THE DRAWINGS

An embodiment of the invention is described below and shown in the drawings. In the drawings:

Fig. 1 is a side view of a hand-held welding device according to the invention with a mounted receiving device for the melting material, the hand-held welding device being mounted on a guide

device partially rests;

Fig. 2 the receiving device, wherein the cord-like melting material is wound on a drum which is fixed on an axis attached to the receiving device;

Fig. 3 shows a section through a nozzle according to the invention for the hand-held welding device, in which supplied melting material and a hot air stream meet in a melting chamber;

0 Fig. 4 a view of the nozzle from Fig. 3 from below,

which shows the outlet opening of the melting material and the opening in front of it for the preheating of the joint by the hot air flow and

5 Fig. 5 Section through a joint located at the

Joint between two panels of floor coverings

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and is welded using fusion material.

DESCRIPTION OF A PREFERRED EMBODIMENT

Fig. 1 shows a hand-held welding device 11, the housing 12 of which has a tubular extension 13 connected to the front, which ends in a thin nozzle extension 14. In the housing 12, a device not shown is used to generate a hot air flow that is adjustable in terms of temperature and flow rate by means of an electric motor with a fan and a heating device, which flows within the tubular extension 13 in the direction of the nozzle extension 14 and exits the nozzle extension 14 to the front. The housing 12 and the tubular extension 13 of the hand-held welding device 11 are preferably cylindrical.

The nozzle extension 14 opens into a nozzle 16 according to the invention, which is attached to it with a nozzle tube 15. A force-locking connection can be ensured either by a suitably designed fit between the two parts, or the connection can be additionally secured, for example by a screw. A melting material holder 17, which is shaped like a short pipe extension, protrudes diagonally upwards from the nozzle 16. Cord-shaped melting material 19 is introduced into it and brought through an outlet opening 18 into a joint 62 located below. If the hand-held welding device is guided in the working direction shown, a protrusion of the melting material 19 is created behind the nozzle 16 in the joint 62. A detailed illustration of the structure of the nozzle 16 can be seen in Fig. 3 and will be described later.

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A receiving device 21 is guided over the housing 12 and is attached to it. It consists of a band-shaped material that encloses at least the lower half of the circumference of the housing 12 and merges into a support frame 22 at the top. The fixing takes place via recesses 23 in the lower part of the receiving device 21, into which projections 24 of the housing 12 engage. The projections 24 are opposite one another and are each provided at the point on the housing 12 at which the receiving device 21 comes to rest on the circumference of the housing from above.

A hole 26 is provided in the receiving device 21 slightly above the recesses 23, through which a long screw or the like can be inserted approximately horizontally, so that it is guided above the housing 12 through both sides of the receiving device 21. A screw of this type can achieve a clamping effect which, together with the connection between the recesses 23 and the projections 24, ensures reliable fastening of the receiving device 21.

A leg 28, which forms part of the support frame 22, can be angled in the direction of the nozzle 16 compared to the receiving device 21 and receives a drum 29 onto which the cord-shaped melting material 19 is wound. For details, see Fig. 2 and the associated description below.

The hand-held welding device 11 rests downwards on a guide device 31, which ensures that the hand-held welding device is guided precisely along a joint 0 (not shown). This guide device 31 consists of two elongated legs 32, which are joined together at their rear end 33.

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are guided, with a narrow wheel 35 sitting on a short axle 34, which is guided in the joint 62. At their other end, the legs 32 are spaced apart so that they form a pointed and isosceles triangle. With their spaced-apart ends, they are attached to a protruding attachment 36 of a fastening device 3. This fastening is also designed as a bearing so that the guide device 31 can pivot in the plane of the drawing. A short axle 38 can be provided for the bearing, which is guided both through the two legs 32 and through the attachment 36. The stability of the guide device 31 can be increased by connecting the two legs 32 to one another in a manner not shown, for example by intermediate webs.

The fastening device 37 is designed here as a type of ring that can be plugged exactly over the housing 12. On the side towards the front part of the hand-held welding device, the fastening device 37 can also have recesses in the style of the recesses 23 of the receiving device 21, into which the projections 24 engage when plugged in. This prevents the fastening device 37 from twisting on the housing 12. Shifting in the longitudinal direction of the housing can be prevented by clamping screws 40, which are screwed in radially into threaded pieces 41 on the fastening device 5 and come to rest against the housing 12. As shown in Fig. 1, the fastening device 37 and the receiving device can be plugged on top of one another.

In order to work optimally with the hand-held welding device 11, it is advantageous if it is held at a certain angle, approximately 20° to 30° of its longitudinal axis to the floor. The underside of the nozzle 16 should always lie flat on the

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Floor covering and/or the melting material 19. This can be achieved by the guide device 31 having a stop 43, which ensures a certain distance between the legs 32 and the fastening device 37 and thus the housing 12. The weight of the hand-held welding device 11 always pushes the guide device 31 as far as it will go in the direction of the housing 12. It is also possible to make the stop 43 from an elastic material, so that a certain spring effect of the stop between the guide device 31 and the housing 12 is provided.

Fig. 2 shows the receiving device 21 in a top view from the perspective of an operator. The special shape becomes clear, which is semi-circular on the underside in accordance with the outer diameter of the housing 12. The recesses 23 are made at the points where the curve turns into the straight part, in this case on the underside. At a certain distance above this, which is slightly more than the radius of the curve, a long screw 45 is guided through the holes 260, onto whose thread 46 on the right-hand side a knurled nut 47 with a large diameter is screwed. By tightening the knurled nut 47 on the screw 45, a cross-section narrowing of the receiving device 21 is brought about in the area in which the housing 12 is enclosed. This section is followed upwards in Fig. 2 by the section of the support frame 22, which is widened in order to be able to accommodate winding bodies or drums 29 of large width. In the area of the ends of the legs 28 of the support frame 22, two holes 0 3 0 are provided, into which a long axle 49 can be inserted. On the left-hand side, it has a diameter constriction on the inside of the leg 28, which protrudes above the leg with a short end 50.

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At its other end it is provided with a thread 51 of smaller diameter onto which a knurled nut 52 can be screwed. Between the knurled nut 52 and the leg 28 there is a conical spiral spring 53, the smaller diameter end of which rests against the knurled nut 52. The larger diameter end runs into a disc 54 whose diameter is slightly larger than the diameter of the spiral spring 53. This arrangement forms the braking means with the adjustment device for the axle 49.

The braking effect is achieved by the fact that the spiral spring 53 presses against the knurled nut 52 on the one hand through its spring force and on the other hand through the disc 54 against the leg 28 of the support frame 22, thus generating friction when the axle 49 and knurled nut are rotated. The height of the spiral spring 53 and thus also the spring force and the braking force can be adjusted by the position of the knurled nut 52 on the thread 51. An improvement in this braking means can also be achieved by the end of the axle with the thread 51 having a radially continuous slot 55 into which the correspondingly bent end of the spiral spring 53, which rests against the knurled nut 52, is guided. In this way, part of the braking means is fixed to the axle 49. In this way, twisting of the knurled nut 52 due to the friction on the spiral spring 53 is also avoided. Furthermore, the thread 51 can be spread in order to prevent the knurled nut 52 from twisting.

The axle 49 with the drum 29 is first inserted with the right thread 51 through the hole 3 0 in the right leg 28 until it stops, then the support frame is widened slightly 0 and the left thinner end 50 is inserted into the hole 3 0 in the left leg 28. The two stops on the

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The axle 49 sits firmly in the support frame 22 on the inside of the legs 28. Alternatively, the narrow end 50 could also be designed as a head with a diameter extension and the axle 49 could be inserted from the left through the widened hole.

Two rotationally symmetrical riders 56, tapered on one side, form the fixing means for the drum. Their conical part is followed by an essentially cylindrical attachment, which serves primarily to fix the riders. As can be seen on the right rider 56, there is a threaded hole 57 in the cylindrical attachment, into which a locking screw 58 is inserted. By screwing this locking screw 58 into the stop on the axis 49, the rider 56 is fixed on the axis. In a preferred embodiment of the mounting device 21 with an axis 49 that is flattened on one side, it is advantageous to turn the locking screw 58 against the flattened side. In addition to fastening with a locking screw, there are a number of other suitable options for fixing the riders 56 on the axis 49.

The drum 29 with the cord-shaped melting material 19 wound on it is clamped by the two riders 56 in such a way that it is also connected to the axis 49 in a force-locking manner by its fixation. The advantage of the conical sections of the riders 56 is that drums 29 with a bore diameter that is considerably larger than the diameter of the axis 49 can also be both fixed and centered on the axis.

A section through the nozzle 16 is shown in Fig. 3. The nozzle rests with a bottom side 60 on a floor covering 61, specifically above a dashed line

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shown joint 62. The nozzle 16 is pushed with the nozzle tube onto a nozzle extension 14 shown in dashed lines, whereby it essentially forms its extension. The opening 64 receiving the nozzle extension 14 can be slightly widened for better handling. In its roughly tubular course, the nozzle leads to an outlet opening 18, which is formed in the underside 60. The essentially straight underside 60 forms an angle of approximately 30° with the longitudinal axis of the nozzle tube, in which a hot air flow 63 shown by arrows also runs. Shortly before the start of the outlet opening 18, the nozzle 16 has a type of projection 65 in the flow channel formed in its interior, which narrows the flow cross-section of the hot air flow 63. Behind the projection 65, however, the flow channel quickly widens and passes into a melting chamber 66.

This melting chamber 66 has the outlet opening 18 on its underside, which is narrowed adjacent to the projection 65 by laterally attached webs 67.

0 In the melting chamber 66, the hot air flow 63 hits the melting material 19 introduced through the melting material holder 17. The melting material holder 17 has an angle of approximately 30° to the longitudinal axis of the nozzle tube 15. It thus forms an angle of approximately 60° with the horizontal.

The melting material 19 can be introduced in a relatively solid or liquid state, as desired, into the joint preheated by a part of the hot air flow 63, which exits a little before the melting material through the narrow part of the outlet opening 18 between the webs 67 and thereby heats the joint 62. By means of a

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The melting material 19 can be pressed downwards into the joint 62 by means of the beak 68 formed by the nozzle 16, which runs on the inside adjacent to the melting chamber 66 in approximately the same direction as the longitudinal axis of the nozzle, and is bent upwards almost to the bottom 60. The user can adjust the temperature and speed of the hot air flow 63 and the working speed as desired so that the melting material 19 in the melting chamber 66 is heated or melted to the desired extent. Even when melting is almost complete, the melting material 19 is pressed into the joint 62 from the bottom of the beak 68. The nozzle 16 partially slides with the bottom of the beak 68 on the protrusion of the melting material 19 in the joint. The upwardly curved section of the beak 68 enables work to be carried out even on curved or arched sections of the floor covering 61.

The outlet opening 18, which begins between the webs 67 and is variable due to their distance from one another, can also have a section separated by a cross web, the cross section of which determines the amount of hot air flowing through and thus also the heating of the joint underneath.

In Fig. 4, the nozzle 16 shown in Fig. 3 is shown from below. You can see how the nozzle tube 15 tapers towards the beak 68, whereby the taper only begins shortly before the melting chamber 66. It is clearly visible that the outlet opening 18 has an elongated course, whereby it begins with a narrow section between the two webs 67. Above the melting chamber 66 you can see the melting material holder 17, which only tapers shortly before it converges with the nozzle tube 15. For better guidance of the nozzle 16 on the floor covering

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61, the webs 67 can, as shown in Fig. 4, run in the direction of the beak 68, becoming narrower, up to the point where the beak 68 and thus the nozzle 16 lifts off the floor covering 61 again. In this way, a sliding surface appropriate to the application is created on the underside 60 of the nozzle 16. Furthermore, it is possible to guide the nozzle on the melt material that has already been introduced.

In Fig. 5 you can see a section through two panels of a floor covering 61, which were glued to a substrate 70 using an adhesive 69. At a joint surface 71, where the two panels adjoin each other, there is an approximately triangular-shaped joint in the upper area. This can either be incorporated into the panel edges of the floor covering or subsequently worked out using a special joint plane.

Molten melting material 19 is introduced into the joint 62, which connects the two plates and closes off the abutting surface 71 at the top. Due to the way in which the melting material 19 is introduced into the joint 62, the melting material has a curved overhang at the top, which must be cut off in a further work step. Depending on the type of floor covering 61, the melting material 19 can be melted with the adjacent floor covering in such a way that certain transition zones form between the melting material 19 and the floor covering. In this way, plastic floor coverings in particular can be reliably and permanently connected to one another.

Claims (12)

Requirements hand welding machine 1. Hand welding device for connecting adjacent surfaces of a floor covering (61), in particular for welding a plastic covering, by means of melting material (19) for heating and introducing it into a joint (62) between the surfaces, wherein the melting material (19) is guided via a feed of a nozzle (16) of the hand welding device (11) and can be heated therein, characterized in that a receiving device (21) for the melting material is provided on the hand welding device. 2. Hand welding device according to claim 1, characterized in that the receiving device (21) is arranged on the hand welding device (11) in such a way that it is located with the melting material (19) essentially above it. 3. Hand welding device according to claim 1 or 2, characterized in that the receiving device (21) has a support frame (22), in particular consisting of a band-like material. A 31 391 - 2 - 4. Hand welding device according to one of the preceding claims, characterized in that the receiving device (21) is attached to the hand welding device (11) at least partially around the outer circumference of the housing (12). 5. Hand welding device according to one of the preceding claims, characterized in that the melting material (19) is cord-shaped and wound onto a winding core, in particular a drum (29) or the like. 6. Hand welding device according to one of the preceding claims, characterized in that the receiving device (21) has an axis (49) which is held in particular on the support frame (22), which carries the winding core carrying the melting material (19) and is rotatably mounted. 7. Hand welding device according to one of the preceding claims, characterized in that fixing means for fixing and centering the winding core are provided on the axis (49). 8. Hand welding device according to one of the preceding claims, characterized in that on the receiving device (21), in particular on the support frame (22), braking means for the axis (49) are provided, which brake a rotation of the axis with an adjustment device for the braking force. 9. Hand welding device according to one of the preceding claims, characterized in that the braking means consist essentially of a preferably conically tapered spiral spring (53) which acts on a support A 31 391 - 3 - frame (22) protruding end of the axle (49) provided with a thread (51) is pressed against a plate disk (54). 10. Hand welding device according to one of the preceding claims, characterized in that the nozzle (16) has a melting chamber (66) which is open downwards towards the floor covering (61) and through which the melting material (19) can be introduced into the joint (62), wherein a hot air flow (63) of the hand welding device (11) in this melting chamber is directed onto the melting material and the floor covering in the area of the joint. 11. Hand welding device according to one of the preceding claims, characterized in that the hand welding device (11) has a guide device (31) by means of which it can be guided exactly along the joint (62), wherein the guide device at least partially supports the hand welding device. 12. Hand welding device according to one of the preceding claims, characterized in that the guide device (31) is provided on the receiving device (21).