RU2491216C1 - Thermo-blade of packaging machine - Google Patents

Abstract

FIELD: packaging industry.

SUBSTANCE: thermo-blade 7 comprises a holder with a cutting element stretched on it in the form of a continuous nickel-chromium yarn and two stretched sealing elements located on opposite sides of the cutting element. The holder is attached to the dielectric plate, e.g. from cloth-based laminate, in which from the sides of its ends the slots are made with compression springs located in them. Each spring rests with its one end to one end of the slider, and the other - to the end of the slot. The other end of each slider is installed in the guide rails of the holder. On the sliders the screws are mounted, which are connected to the cutting and sealing elements, the negative electric wire and positive electric wire for supplying current to the sealing and cutting elements. The plate is fixed to the holder with the screws located in its slots poured with dielectric cured composition. Under the holder a rest is located with nonstick heat-resistant self-adhesive fabric on it, located such that in operation the cutting element is pressed to the nonstick fabric through the weldable film. The nonstick fabric is located over the plate glued onto the rest, made of the porous or elastic dielectric material and fixed on it with planks attached with screws to the sides of the rest.

EFFECT: invention provides a simplification of the design and increased reliability of its work.

11 dwg

Description

The technical solution presented in this description relates to packaging machines for packaging products in shrink film, the main part of which is a thermal knife and means of moving it.

Known welding sponge of a packaging machine containing two clamps and a heater, the clamps are located on the working surface of the sponge indented from the heater (RU 2348838 C2, F16B 11/00, B65B 51/22, 03/10/2009).

A device for packaging thermally adhesive material containing welding elements and a transverse cutting mechanism, including a retractable knife, a cutter in the form of sponges that are mounted on the carriage (RU 2165382 C1, B65B 9/06, 02/10/1998).

A device for splicing thermoplastic tapes containing a welding unit, a cutting tool consisting of heating elements (RU 99116015 A, B65B 41/12, 05.20.2001).

A device for connecting a film (options) containing clamps, cutting knives, levers on which a heater and a knife are mounted (RU 2130411 C1, B65B 41/12, 05.20.1999) is known.

Known thermal knife packaging machine containing heat sealing elements, cutting and stitching knives, providing the formation of two transverse edges of the packaging (RU 2391266 C1, B65B 9/06, 06/10/2010).

Known welding sponge of a packaging machine for making a weld in heat-sealable packaging material, containing clamps to the welded materials of the working surfaces and made in the form of a rod heater, characterized in that it contains a clamp located on the surface of the sponge indented from the heater and protruding above the sponge (RU 2005115841 A, B65B 1/22, 07.27.2006).

A known packaging machine with independent cutting and welding rods containing the first longitudinal and second transverse cutting and welding rods (RU 2008135949 A, B65B 9/06, 03/20/2010).

A device for welding a film containing clamps and a heater (RU 95117113 A, B65B 41/12, 12/27/1997) is known.

A packaging machine is known that contains welding and cutting units of the film, which are located separately from each other and are arranged to move towards each other, and the cutting unit is equipped with a knife made with the possibility of its extension for cutting the film (RU 71630 U1, 03.20.2008 )

A device is also known in which there is a welding mechanism comprising a spring-loaded thermal knife pivotally connected to the rear wall of the fixed frame (RU 5171 U1, 10.16.1997).

A known installation for packaging products in shrink film containing mounted on the base of the heating elements, while along the perimeter of the lower part on two adjacent sides are linear heaters of the welding device made of nichrome wire (RU 95118220 A, 10.10.1997).

The complexity of the construction of the thermal knife has a negative impact on the reliability of its operation, which leads to the need for adjustment and repair work, which ultimately significantly reduces the productivity of the knife.

The technical result of the invention is to simplify the construction of the thermal knife and increase the reliability of its operation.

The technical result was obtained by a thermal knife of a packaging machine, comprising a holder with a cutting element stretched over it, made of a solid nichrome thread, and with two tensioned welding elements located on opposite sides of the cutting element, a dielectric pad made of dielectric material, for example, PCB, is attached to the holder at the same time, nests with compression springs located in them are made in the overlay on the sides of its ends, each spring abuts against one end with one end, a slider and with its other end it abuts against the end of the socket, while the other end of each slide is installed in the guides of the holder, the sliders have screws that connect the cutting element, welding elements, a negative electric wire for supplying current to the cutting element and a positive electric wire for supplying current to the cutting and welding elements, whereby the dielectric pad is fixed to the holder with screws located in the socket of the pad, and these sockets are filled with a dielectric cured composition, while holding the body is equipped with an abutment with a non-stick heat-resistant self-adhesive fabric on it, the abutment is positioned in such a way that during operation of the thermal knife the cutting element is pressed against the non-stick abutment fabric through a film to be welded, the non-stick abutment fabric is located above the adhesive bonded to it, made of porous and elastic dielectric material , the non-stick fabric is fixed to the stop with strips attached by screws to the sides of the stop.

1 shows a thermal knife mounted on a frame of a packaging machine.

In Fig.2 - view A in Fig.1.

Figure 3 - node connecting the spring with the levers of the mechanism for raising and lowering the knife.

Figure 4 is a view of B in figure 3.

Figure 5 shows the attachment of the thermal knife to the frame of its movement.

Figure 6 is a view In figure 5.

In Fig.7 is a section GG in Fig.5 (enlarged).

On Fig - place W in Fig.7 (enlarged).

Figure 9 is a cross section DD in figure 5.

Figure 10 - place E in figure 5 (enlarged).

11 shows the emphasis of the thermal knife.

The thermal knife (packing line assembly) is mounted on the frame 1 of the packaging machine (Fig. 1), on which the racks 2 are fixed, and each of them has a U-shaped cross section. In each U-shaped opening of the rack 2 there is a stretched rod 3, one end of which is fixed with the possibility of tension on the upper part of the frame, and the other end is fixed on the lower part of the frame. The ends of the rod 3 are fixed with the possibility of their movement relative to the frame and the possibility of tensioning the rod. On each rod 3 with the possibility of sliding mounted slider 4, made in the form of an elongated cylindrical sleeve. The lower bar 5 and the upper bar 6, respectively, are connected to the sliders, which together with the sliders form a frame for moving the thermal knife 7 in the vertical direction. The thermal knife 7 is fixed on the upper bar 6, on which the handle 8 for moving the thermal knife is also fixed. On the racks 2 there is a fixed stop 9 of the thermal knife (FIGS. 2, 11) located under the thermal knife 7 with the possibility of their contact in the working position.

A magnetic cup 10 is fixed on the lower bar 5 (Fig. 2), which is located with the possibility of its contact with an electromagnet 11, mounted on a rod 12 with the possibility of adjusting the height of the electromagnet relative to the frame 1. The adjustment is made by a pin 13 screwed into the rod 12 and the electromagnet 11. The lower arm 15 is fixed on the frame 1 by the hinge 14. The upper arm 17 is fixed by the hinge 16 on the lower bar 5. The levers 15 and 17 have a hook 18, which is round in cross section, welded to each of them and engages with the spring coils 19 connecting second ends of the levers 15 and 17. The spring has a cylindrical shape and its turns run on a bend. The stiffness of the spring is selected from the calculation of its bending in the longitudinal plane of the packaging machine at an angle in the range from 170 to 15 degrees. In the initial position, the device for raising and lowering the thermal knife is mounted on the frame so that between the levers 15 and 17 and the branches 20 and 21 of the spring a predetermined angle is formed in the range from 15 to 90 degrees.

The thermal knife in its relationship with the above-described assembly of the packaging line or machine contains a holder 22 attached to the upper bar 6 (Fig. 5), connected by pins 23 to the upper bar 6. The holder 22 is designed for fastening and holding the cutting element 24 in it, in tension, made in the form of a continuous nichrome thread, as well as for fastening and holding in tension the two welding elements 25 (Fig.6-8), which are located on opposite sides of the cutting element 24. A dielectric plate 26 is attached to the holder 22 material, for example, from textolite. In the overlay from the side of its ends, nests 27 are made (FIG. 5) with compression springs 28 located in them, one of which is located in a compressed position between the slider 29 and the end of the nest 27, and the other is between the slider 30 and the end of the other nest 27 (FIG. .10) located on the opposite side of the holder. The sliders 29 and 30 are installed at one end in their respective slots 27, the other end of each slide is installed in the guides 31 of the holder 22. On the slider 29 there is a screw 32 (Fig. 6, 10) for fastening the cutting element 24 to the slider and a screw 33 for fastening the welding element 25, while the negative electric wire 34 is also fixed by a screw 32 on the slider. The welding elements 25 are fixed by one end on one of the guide rails of the holder 22 by the upper screws 33 (Fig. 6), and the other end by screws 33 on the slider 30 (Fig. 5 ) A positive electric wire 34 (Fig. 6) for supplying current to the cutting and welding elements is fixed on the slider 30 by a screw 32. The cover 26 (Fig. 9) is fixed to the holder 22 by screws 35 located in the nests of the plates, while the nests are filled with dielectric glue 36.

The holder 22 is located above the stop 9 in such a way that during operation of the thermal knife, the cutting element 24 is pressed against the non-stick fabric 37 (Fig. 11) of the stop 9 through a weldable film (the film is not shown). The non-stick fabric 37 of the stop is located above the bonded 38 to the stop 9 made of a dielectric material. The pad 38 is made of porous and resilient material. The ends of the cutting element 24 and the welding elements 25 are connected to electric wires 34 and 39 (Fig. 6), which serve to supply current for the purpose of pulse (intermittent) heating of the cutting element 24 and the welding elements 25. The negative electric wire 34 is electrically connected to the metal case of the holder 22 and mounted on it.

The stop 9 is installed on the table 40 of the packaging machine (figure 2). Non-stick self-adhesive fabric 37 (11) is made of heat-resistant, for example, Teflon, and this fabric covers the top and sides of the pad 38, which is glued to the stop. The non-stick self-adhesive fabric 37 is fixed on the abutment by clamping strips 41 attached by screws 42 to the sides of the abutment 9. A non-stick fabric 37 is also equipped with a thermal knife (Fig. 8), while the thermal knife fabric 37 is located between the cutting element 24 and the welding elements 25 of the thermal knife.

The thermal knife works as follows. Lay on the table 40 (figure 1) packaged in film products. The handle 8 is manually lowered down by the thermo-knife 7. At the same time, the lower bar 5 (FIG. 2) is lowered together with the thermo-knife, the magnetic cup 10 is joined to the electromagnet 11, and they are magnetized to each other. In this case, current begins to be supplied via wires 34 and 39 (Fig. 6) to the cutting and welding elements 24 and 25 and they heat up. In this case, the welding elements 25, which weld the ends of the packaging film with two parallel welding seams, are pressed to the ends of the film into which the products are packed and to the lining 38 of the stop 9 wrapped by the non-stick fabric 37 (Fig. 11). Moreover, one welding element 25 welds the ends of the packaged products, and another welding element welds the ends of the film sleeve for the next product packaging. At the same time, the heated cutting element 24 (Fig. 8) presses the welded ends of the film (not shown) to the non-stick fabric 37 (Fig. 11) and through it to the pad 38 of the stop 9. The ends of the film are melted and cut by the cutting element 24. In this case, the cutting the element 24 is pressed against the non-stick fabric 37 (Fig. 8) of the thermal knife 7. After holding a predetermined period of time from the action of the time relay, the supplied current to the electromagnet stops, the electromagnet 11 is demagnetized and the cup 10 moves away from the electromagnet. Simultaneously with the end of the current supply to the electromagnet, the current to the electric wires 34 and 39 ceases to be supplied, and the cutting and welding elements cease to heat up. Thanks to the non-stick fabric used, the molten film does not adhere to the cutting element 24 and the welding elements 25, and these elements remain clean for the next cycle of operation. Under the action of the spring 19, the thermal knife 7 rises, and then the described cycle is repeated.

When the thermal knife 7 is operating, its up and down movements are carried out as follows. When the thermal knife moves down, the levers 15 and 17 (FIG. 1) of the mechanism for raising and lowering the thermal knife rotate around the hinges 14 and 16 (FIG. 2), come together, and the angle between the levers decreases. In this case, the branches 20 and 21 (FIG. 3) of the spring 19 come closer, the angle between these branches decreases, and the turns of the spring in the bending zone take the position shown in FIG. 3. In this case, the thermal knife 7, the sliders 4, the lower and upper strips 5 and 6, forming the frame of the thermal knife, turn out to be spring-loaded with a spring 19, which with its elasticity tends to raise the thermal knife 7 up.

The technical result is achieved due to the maximum possible simplicity of the design of the mechanism for raising and lowering the thermal knife, which contains essentially several interconnected elements that provide a high degree of reliability. Improving the reliability of the thermal knife is achieved due to the relative position of the cutting element and the welding elements on top of each other, the choice of elasticity of the lining stop. The specified elasticity of the lining provides a given sequence of operation of the welding elements and the cutting element.

Claims (1)

A thermal knife of a packaging machine, characterized in that it comprises a holder with a cutting element stretched over it made of a solid nichrome thread and with two tensioned welding elements located on opposite sides of the cutting element, a dielectric pad made of dielectric material is attached to the holder, for example, PCB, while in the patch on the sides of its ends there are nests with compression springs located in them, each spring abuts one end at one end of the slide, and others with its end, it abuts against the end of the socket, while the other end of each slide is installed in the guides of the holder, the sliders have screws that connect the cutting element, welding elements, a negative electric wire for supplying current to the cutting element and a positive electric wire for supplying current on the cutting and welding elements, whereby the dielectric pad is fixed to the holder with screws located in the socket of the pad, and these nests are filled with a dielectric cured composition, under the holder there is a stop with a non-stick heat-resistant self-adhesive fabric on it, the stop is positioned so that during the operation of the thermal knife the cutting element is pressed to the non-stick fabric of the stop through the film to be welded, the non-stick fabric of the stop is located above the adhesive bonded to the stop made of a porous and elastic dielectric material, non-stick the fabric is fixed to the stop with strips attached by screws to the sides of the stop.

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