WO2022196268A1 - Impulse sealer of low-voltage zigzag line - Google Patents

Abstract

[Problem] An impulse sealer for sealing a plastic bag needs large power to rapidly increase the temperature of a heater and needs to radiate heat to a heater board to decrease the temperature. Therefore, a 20 cm handheld sealer needs a hand grip code to cause 50 A current to flow and is difficult to use due to its thickness. In addition, the sealer heats up a holder with heat radiation and needs a heat-insulating glove.　[Solution] In the present invention, a maximum voltage within a safety standard is selected with the use of a transformer, a current is minimized, an electrification prevention film is removed, a zigzag line is caused to exhibit original strength of heat generation, and needed power is reduced to 50 to 30% of that of conventional impact sealers. The current is reduced to 7A, and the hand grip code is thinned. Further, heat insulating properties of a heater board is increased to prevent the holder from being heated.　The present invention is also applied to a general sealer. Power usage is reduced, or the heater is conversely upsized to increase energy efficiency.　

Description

Impulse sealer for low voltage zigzag wire

　It is about the impulse heat sealer.

For impulse heat sealers that seal polyethylene bags and films (hereafter referred to as plastic bags), it was necessary to raise the temperature of the heater rapidly and quickly dissipate the heat after heating. Therefore, a large amount of power is required for a short period of time, and in order to dissipate heat, the heater base is made of aluminum with good heat conductivity and large heat capacity, and is insulated with two thin glass tapes that do not short-circuit between it and the heater wire. Was.

So, for example, 1 Kw of a hand-type sealer with a length of 20 cm and a width of 1 cm was required for packaging and large bags. Since the length of the ribbon wire is 20 cm, the maximum voltage is 20 V, and a thick hand cord that carries 50 A was required. Therefore, it was very difficult to use. In addition, the large amount of heat made the holder very hot, requiring heat-resistant gloves during use.

Even for sealers for production and stores, high power was difficult. For example, 1.5 Kw was required to seal a medical sterilization bag with a length of 30 cm and a width of 10 mm. This rapid heating is the result of efforts to seal plastic bags as quickly as a fraction of a second, even though they are poor conductors of heat. As a result, the area around the heater, especially the release film, was greatly worn, and it took time and effort to replace it.

In addition, conventionally, the heater wire was a ribbon wire that expanded and contracted each time it was heated, so a traction device with a complicated structure was required. The inventors invented a zigzag heater wire (hereinafter referred to as zigzag wire) in which a slit is formed in a ribbon wire as in Patent Document 1, thereby eliminating the need for a traction device and the like, and eliminating a heavy transformer from the power supply circuit. However, even with half-wave rectification by a diode, 100 V of the power supply came to the heater wire instead of the 50 V described in Document 1.

Therefore, a polyimide thin film for preventing electric shock was essential, as in Patent Document 2. There are regulations on safe voltages for electrical appliances in various countries, and international regulations are being established (hereinafter referred to as safety standards). When the film was attached, the heat conduction was noticeably worsened, but the heat generated by the zigzag wire was more than sufficient, so there was no problem. Although the polyimide thin film required more cost and time to apply, the inventor aimed for a simple sealer structure and light weight, so the advantage of eliminating the heavy transformer was irreplaceable.

On the other hand, in the world, power supplies that drop from the commercial voltage of 250V to 100V to around 20V and 3A have become commonplace as power supplies for personal computers. Even if I wanted to use it, the width of the heater had to be 0.7 mm for a ribbon wire of 20 cm in length at about 60 W. In general, as a sealer, if the seal width is wide, the product in the bag looks luxurious and the value increases, but this was the opposite, it was too thin and poor and could not be used.

Patent No. 3943934 Patent application 2003-171173

I wanted to make the hand cord of the hand-type sealer for packaging and large bags thinner and prevent the holder from overheating.

We wanted to save energy for the sealers for production and stores, and reduce the time-consuming replacement of the release film.

I also wanted a convenient sealer that can be used anywhere in the world by borrowing the power supply of a familiar computer, smartphone, USB, and car cigar power supply.

The heater wire was made into a zigzag wire and operated within the voltage within the safety standards.

Furthermore, the power consumption per unit area of the heater has been reduced to 50-30% of the conventional level. I also improved the insulation of the heater base.

The electric current of the hand-type sealer has reached 7A. As a result, the hand cord became thinner and it became very easy to use. Heat dissipation to the heater base is also reduced, and the holder can be held with bare hands.

　Conventional tabletop and foot-operated sealers made it possible to seal wide medical sterilization bags by increasing the product value by increasing the sealing width by 3 times while keeping the transformer as it is, or conversely by reducing the transformer to 1/3.

By changing the pitch of the zigzag lines to match the 20V, 3A power supply of familiar personal computers, a clip-type sealer with a length of 20 cm and a width of 2 mm was realized. Even a smartphone or USB power supply could be used for a sealer with a length of 5 cm and a width of 2 mm. Originally these power supplies can be used at 100 to 250V, so they can be used all over the world.

　Since the heater raises the temperature relatively slowly, the life of the release film has been extended and the frequency of replacement has been reduced.

1 is a cross-sectional view of part of an example of a heater of the present invention; FIG. 1 is a cross-sectional view of part of an example of a conventional heater; FIG. 4 is a graph of heating time versus temperature at each power of the heater of the present invention; FIG. 4 is a plan view of an example of zigzag lines;

　In Embodiment 1, Figures 1 to 4 show the application of the present invention to a hand-type sealer and a desktop-type sealer. In Example 2, we will explain a sealer that uses the power supply of a personal computer or a smartphone, and a sealer that does not have a switch or timer.

The heater wire of the conventional hand-type sealer for export packaging of large poly bags and nylon lamination is a ribbon wire of iron chromium or nichrome with a thickness of 0.1 mm. Alternatively, a total power of 1 Kw is required for both sides, and a current of 20 V and 50 A flows through the cord at hand. Therefore, the cord had a diameter of 16 to 20 mm and was difficult to operate.

The resistance value of 0.4Ω can be reduced somewhat, but cannot be increased. The reason is that electrical resistance wires, including zigzag wires, use steel materials with the highest specific resistance and have a thickness of 0.1 mm. In other words, if the size is the same, the resistance value is almost the same. At present, only the zigzag line can be processed to increase the resistance value by inserting a slit.

Therefore, in the present invention, the zigzag line 1 as shown in FIG. 4 is used, the resistance value is increased, and the amount of electric power is reduced to about 1/3. First, the operating voltage was increased from 20 V to the maximum safety standard of 45 V, and then rectified to direct current. Therefore, targeting 315 W from 45×7, the resistance of the zigzag line went from 45÷7 to 6.43Ω. This was achieved by a zigzag line in which 0.2 mm slits were alternately inserted from both left and right sides at a pitch of 1.96 mm from both sides in a 10 mm wide iron-chromium ribbon wire.

Furthermore, as shown in Fig. 1, the heater of the present invention has a voltage within the safety standard, so the polyimide anti-shock film, which was always placed on the zigzag line until now, is not placed. Then, rather than sticking only one release film of fluororesin tape 2 with a thickness of 0.08 mm, it is stacked, and the heater stand underneath is two sheets of glass tape 3 with a thickness of 0.2 mm, which is usually an extruded aluminum material. A heat-resistant bakelite 4 was placed at a position where This heater is fixed to a holder (not shown).

For the release film 2, a 0.08 mm fluororesin tape without an adhesive layer in the center is used, and an adhesive layer with a thickness of 0.05 mm is provided on both sides of the heater, and fixed to the side wall of the heater base. Therefore, as shown in FIG. 1, the fluororesin tape 2 is not brought into close contact with the heater wire 1 and is fixed so that there is some slack. I made a structure like

As a result, the cord at hand has become as thin as 8-10mm, making it softer and easier to operate. Regardless of the first time, from the second time onwards, the holder did not get hot even when the seal was continuously applied, and it became possible to hold it with bare hands.

Looking at the conventional heater in FIG. A 0.05 mm-thick polyimide anti-electricity film 6 and a 0.13 mm-thick fluororesin tape 7 with an adhesive are attached. When the press mechanism is closed, a 0.1 to 0.2 mm plastic bag or the like (not shown) is placed on top of the press mechanism, and the heat flows to the silicone rubber on the opposite side.

The polyimide film alone of the anti-electric shock film 6 is thin, but when including the adhesive, it is about 1/4 that of the glass tape. In addition, since it is attached to the side wall of the heater base, even if the very small amount of remaining air around the heater wire expands during heat generation, there is no place for it to escape, and it is thought that heat conduction is hindered. This is an empirical value when sealing a normal plastic bag with a zigzag line clip type sealer, but before and after pasting, the sealing time was slowed from 0.7 seconds to 1 second. However, even with such an anti-shock film as an obstacle, the rise of heat generation was higher than that of the ribbon wire.

From these, we can roughly say that the heat generated by the heater is divided in half, and half of the heat is wasted. Considering the reason for increasing the heat dissipation to the heater table, the conventional sealer is based on the premise of timer and continuous use, and the heater returns to the original temperature every time, and the heating time from there is constant. It can be said that it is because it is based on the premise of using a timer.

　Glass cloth tape not only has high electrical insulation, but also has high thermal properties. Therefore, if it is a short period of 1 to 2 seconds during heating, just putting a piece of glass tape on the conventional aluminum extrusion material will have a certain thermal insulation effect. However, since the conventional ribbon wire stretched and moved, it is thought that two wires were used as a precaution to prevent a short circuit even if the wire were torn.

Therefore, even if you add two more, the effect will not be great in the short time during heating. And as the opposite case will be described later, the effect appears in the case of long heating time. If the interval between sealing operations is large, the heat is cooled by the heater pedestal and air cooling while the press mechanism is open.

However, if you work continuously until you finish sealing a large bag with a hand-type sealer, there will be fewer opportunities for air cooling, and the heat that accumulates on the heater base will go to the holder. That's why I changed to bakelite to minimize the waste heat going to the holder. Of course, ceramics and heat-resistant plastics can also be used as long as they have a high heat insulating effect.

As a result, the holder did not get hot, but the temperature of the heater increased. In the present invention, a slightly raised state is desirable, but there is concern that the height will be too high, and as a result, it will take time to cool down at the production site, slowing down the work.

In that case, when the press mechanism starts to open, loose release film 2 adheres to the plastic bag still attached to the silicon rubber side as shown in FIG. If the structure is separated, the effect of air cooling is very large. A structure in which the release film is fixed to a frame separate from the heater and moved up and down like a hot plate sealer may be used. They allow the press mechanism to open earlier and speed up the rotation.

The effect of the sealer of the present invention described so far is for polyethylene or polypropylene, which makes up the majority of so-called plastic bags, and laminate films and bags made of them and nylon. It is not a special metal film or laminated film with aluminum foil (hereinafter referred to as aluminum lami). Aluminum lamination takes a lot of heat from the aluminum foil, so even a conventional hand-type sealer requires power of 1 Kw or more. Therefore, it is appropriate to treat it separately as a dedicated machine as before, but the sealer of the present invention can be done without reducing the power.

Using the zigzag line according to the concept of the present invention, plastic bag sealers that used conventional transformers can also reduce power consumption by half to one third. For example, the electric power of a medical sterilization bag sealer of 30 cm in length and 10 mm in width could be reduced from 1.5 Kw to 500 W.

On the other hand, we were able to increase the value of the products we sell by increasing the seal width to 5 to 6 mm while maintaining the 200W for the store sealer with a length of 20 cm and a width of 2 mm. It is also possible to reduce the size of the transformer to 70 to 50W. There is almost no difference in usability.

The graph in Fig. 3 shows the heat generation situation due to the difference in electric power according to the present invention. A clip-type sealer with a length of 20 cm and a width of 2 mm, which is conventionally used at 200 W, is changed to the specifications of the present invention, and the voltage applied to the heater wire is changed to change the power amount to 200 W, 68 W, 36 W, 24 W, and 20 W. , which shows the relationship between heating time and temperature. Since this zigzag line has a resistance value of 25Ω, 68W is obtained by applying a voltage of 41.2V AC. If you want to make the voltage within the safety standard, you can make it 30V by changing the resistance value of the zigzag line to 13Ω.

The specifications of the experimental machine are that the heater wire is a zigzag wire, and the heater stand is made of 2 + 2 glass tapes on the extruded aluminum material, a total of 4, to improve the heat insulation a little, and the thickness is 0 without pasting the polyimide film. A release film of 13 mm fluororesin is pasted. This heater wire is 4 square centimeters and 200 watts, so 50 watts per square centimeter. 20 cm width 2 mm sealers for many conventional ribbon wires are the same at around 200 W.

On the other hand, polyethylene bags as thin as 0.03 to 0.05 mm can be sealed at 90°C or higher. Confectionery bags of 0.08 mm and nylon lamination reach nearly 100°C. Polypropylene bags require 110°C to 120°C. In the case of continuous industrial use, the heating time is 1 to 2 seconds, and the cooling time is 3 to 4 seconds. think.

Considering the above requirements, the temperature rise curve during heating, the cooling curve, and the triangle drawn by the 90°C line roughly as the amount of heat that contributes to the seal, the heating time is 1.5 seconds at 200W and 2.5 at 68W. Second, 36W is equivalent to about 6 seconds. Adding 2 seconds of cooling time gives 3.5 seconds, 4.5 seconds and 8 seconds respectively.

In other words, even if the power is 68W, which is one-third, the difference is only about 1 second, and if it is half the power, 100W, it is in the middle, so there is a delay of about 0.5 seconds. Furthermore, the rise of 200W of the conventional ribbon wire or zigzag wire with an anti-electric film is between 200W and 100W in the graph, so the difference is small. If the heat accumulates from the second time onwards, it is thought that it will become even smaller.

When the power is reduced, when energized at 24W, it will stick out of a thin bag in about 5 seconds, and most plastic bags can be sealed in 10 seconds. When energized at 20 W, a thin bag started to stick in 10 seconds, and a thick bag took nearly 20 seconds. 10% is the limit.

In other experiments, if the heater table was the same as before, that is, if there were only two pieces of glass tape on the aluminum extruded material, the limit was 24W, which is one rank lower. This is thought to be because the longer the heating time, the easier it was for the heat from the heater stand to reach the extruded aluminum material through the thinner glass tape.

The seal must be reliable, but when it is used occasionally, the room temperature will affect it, so it is better to check it one by one. However, this is not possible in mass production. A countermeasure for this is to include a precise temperature control device in the circuit. The temperature of the heater is detected by a sensor such as a thermocouple, the time is measured by the microcomputer, the amount of heat is calculated as indicated by the triangle in the graph above, and when the sealing is completed, the lamp notifies and stops the heating. Already used by other models.

The power supply of the personal computer is around 20V3A. With the structure of the present invention, a zigzag line in which 0.2 mm slits are alternately left and right in a 2 mm width ribbon line at a pitch of 0.9 mm is 20 cm and has a resistance value of 6.7 Ω, so it is 20 V3 A and about 60 W. It is 30% of the conventional one. Therefore, the heating time is delayed by about 1 second. Its power supply is 100-250V input, so the sealer can be used worldwide.

A 5V 2.5A power supply for smartphones can be used by setting a zigzag wire with a length of 5cm and a width of 2mm to a resistance of 2Ω. This is 25% of the average sealer since the area of the heater wire is 1 square cm and the power is 12.5W. If the width is 1.5mm, the length can be extended to 7-8cm. The ribbon wire is only 5 cm long and 0.5 mm wide.

The power supply from the car's cigarette lighter socket is 12V and the current can be 20A or more, so if you use 10A with a ribbon wire, you can make a 12cm wide 2mm sealer. However, if a zigzag wire is used to make a 5Ω heater wire, the current flowing through the same size sealer is only 2.4A. 25% of the average sealer works fine.

When using these power supplies, the current is small, so the timer can be made not only with a thyristor but also with a low-power transistor. However, if the power to the heater is reduced to one-third or less, the silicon adhesive will not burn and smoke will be emitted if the power is continued for less than one minute. In other words, even if the heating time of the sealer is doubled from 4 to 5 seconds to 8 to 10 seconds, or even tripled, there is no harm. Therefore, for occasional use, it is easier and more realistic to eliminate the timer.

If the timer circuit is eliminated, the cord and power switch are the same. Without it, there is a great advantage in terms of parts, failures, and manufacturing costs. Instead of the timer, you can keep pressing the power switch for 5 seconds or 10 seconds. The switch should also be eliminated, and the external power supply and the connector should be brought into contact.

If there are no timers or switches, you may forget to turn off the power in case of emergency. As a safety measure, a current limiting element such as a current fuse or a PTC thermistor may be inserted into the circuit. Normally, it is used for an abnormal amount of current, but the sealer of the present invention can be set to the specified value for the current that continues to heat.

It can be said that the greatest advantage of the present invention is the workability of the zigzag wire, which can increase the resistance value, which is impossible with ribbon wire. As a result, as described so far, the length, width, applied voltage, and current required for the sealer can be adjusted quite freely.

The next advantage is that it is thermally light and has a high heat generation rate. The heater wire of the clip-type sealer of the experimental machine has a current-carrying portion of 0.4 mm and a slit of 0.2 mm. One-third of the heater area is therefore air. In addition, there is no traction device at both ends, and there is also a structure that makes it difficult for heat to escape from the heat generating part to the electrodes and lead wires. By keeping the voltage within the safety standard, the anti-electric shock film was eliminated, and these advantages were fully demonstrated.

The zigzag wire of the present invention has various shapes in Patent Document 1, but since it is also a substitute for the ribbon wire, it can be said that the zigzag wire has a shape in which slits are alternately formed from both sides of the ribbon wire. Its springiness eliminates the need for traction devices on both ends.

The sealer of the present invention includes a type that is held by hand and pressed against a plastic bag with silicone rubber laid underneath. It is considered that the human body is also included in the press mechanism. It should be noted that up and down in the above sentences simply indicate the direction.

With this invention, the power consumption of all sealers has been reduced, heat generation and heat dissipation have been reduced, making it an energy-saving product.

The hand-type sealer, which was the first purpose, has a thinner hand cord and is easier to use. Furthermore, the heat dissipation from the heater base is minimized, and the holder can be held with bare hands.

Even in the case of the conventional desk-top or foot-operated sealers, it is possible to increase the product value by increasing the sealing width by 3 times without changing the transformer, or by reducing the transformer to 1/3 to enable wide sealing of medical sterilization bags. became.

We were able to use the power supply of a familiar computer, smartphone, USB, and cigar socket as an easy-to-use sealer. These products are available worldwide.

By creating a structure in which the release film first separates from the heater, we were able to speed up the sealing cycle.

　The heater raises the temperature more slowly than before, so the life of the release film has been extended.

1 zigzag heater wire 2 release film 3 glass tape 4 heat resistant bakelite 5 aluminum extruded material 6 anti-electric shock film 7 release film

Claims (5)

A plastic bag or the like is sandwiched between the press mechanism, and electricity passes through a power supply circuit consisting of at least a connector that contacts an external power supply, a cord, a power switch, a timer circuit, and a transformer depending on the power supply voltage, heating the built-in heater and separating it. In the impulse heat sealer that welds a plastic bag or the like through a mold film and cools it by power interruption and air cooling, the heater wire that heats the above heater is a zigzag wire and must be used at a voltage within the safety standard. Impulse heat sealer featuring. A claim characterized in that the electric energy of the heater wire is 70 to 10%, preferably 50 to 30%, based on the electric energy of the conventional heater wire, which is 50 W per square cm. The impulse heat sealer of item 1. Claims 1~ characterized in that the heat insulating property is improved by adding one sheet of glass tape or more to the heater stand under the heater wire or by changing the material of the heater stand. 2 impulse heat sealer. An impulse heat sealer according to any one of claims 1 to 3, wherein the release film is structured such that when the press mechanism begins to open, the release film is first separated from the heater like a hot plate sealer. . An impulse heat sealer according to claims 1 to 4, characterized in that any or all of the cord, power switch and timer circuit are eliminated from the power circuit.

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