RU2798856C2 - Rotary device for pulse welding - Google Patents

Abstract

FIELD: pulse welding.

SUBSTANCE: group of inventions relates to a rotary device for pulse welding, a machine for forming and filling in a vertical direction, made with the possibility of packaging loose or flowing material, a method for forming packages containing loose or flowing material, as well as to a package containing loose or flowing material. The rotary pulse welding device has a roller rotatable around an axis. The roller has a roller body and a plurality of welding knives extending radially outward from the roller and spaced apart from each other around the roller body. At least one of the welding knives has a main body and a selectively heated heating element extending along at least part of the length of the main body of the welding knife. The roller is rotatable through a pre-heating pressure application zone that allows pressure to be applied to the joint zone of the material to be bonded by means of the at least one welding knife, followed by a heating zone that allows the joint zone to be heated by means of given at least one welding knife. The pressure application zone before heating and the heating zone are stationary with respect to the rotation of the roller.

EFFECT: group of inventions ensures the reduction of rejects in welded joints of the material.

28 cl, 4 dwg

Description

FIELD OF TECHNOLOGY TO WHICH THE INVENTION RELATES

The present invention relates to a rotary pulse welder for forming a series of discrete joints in a material to be joined. The invention also relates to a machine for molding and filling in the vertical direction. In addition, the invention relates to a method for the formation of packages intended to contain bulk or flowable material.

BACKGROUND OF THE INVENTION

Known packages or sachets are formed from layers of plastics and/or metal foils which are bonded together by lamination to form a sealed container between adjacent layers to contain the contents of the package.

Such packages are typically made using methods and apparatus similar to those used in the printing industry, in which elongated webs are passed along a line of stations. Each station performs a function different from the others. Typically, the product to be packaged is inserted between two webs that are welded together continuously along their opposite edges. The webs are also welded transversely at intervals to separate the webs into individual components. Individual packages are obtained by cutting the webs in the transverse direction in the area of the transverse welds.

In this specification, where reference is made to patent specifications, other external documents, or other sources of information, it is generally to provide context for consideration of the features of the invention. Unless specifically stated otherwise, reference to such external documents or such sources of information should not be construed as an admission that such documents or such sources of information in any jurisdiction constitute prior art or form part of the general knowledge in the art.

New Zealand Patent Specification NZ 547925 describes a sachet for storing and dispensing flowable material. The sachet contains a multilayer material of the first, second and third layers. The second layer is a semi-rigid layer located between the first and third layers. A line of weakening is formed in the middle part of the second layer. At least part of the weakening line has interdigitated finger-like parts. The sachet is made with the possibility of bending along the line of weakening when a compressive force is applied at the edges of the second layer. The ends of the interdigitated finger portions cause the first layer to break near the line of weakness to form an outlet through which the contents of the sachet can be released.

US Pat. No. 7,247,219 describes a rotating cylindrical roller for heat sealing heat sealable materials, in particular for sealing flexible packaging. The rotating roller has at least one cooling zone and at least one heating zone. The movement of the heat sealable material over the heating zone causes the formation of a heat seal weld. Moving over the cooling zone allows the weld to be cooled in a maintained state.

When using a rotating cylindrical roller to form the transverse connecting portion and to seal the flowable material within the package, there is a risk that the contents of the package will be dislodged and/or crushed in the package by the action of the roller. This results in the possibility of uneven distribution of the contents in the packages and/or the creation of poor quality seals.

The object of at least the preferred embodiments of the present invention is to overcome some of the aforementioned disadvantages. The complementary or alternative task is to at least provide the public with a useful choice.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, a rotary pulse welder is provided for forming a series of discrete joints in a material to be joined, the rotary pulse welder comprising: a roller rotatable about an axis, the roller having a roller body and a plurality of welding knives extending radially outward from the roller and located at a distance from each other around the roller body, wherein at least one of the welding knives has a main body and a selectively heated heating element extending along, along at least part of the length of the main part of the welding knife, a tensioned belt for supplying a material that can be joined to the roller, while the roller is rotatable through the pressure application zone in the rotary pulse welding device before heating, in which at least one welding blade is configured to apply pressure to the joint zone of the material to be bonded, and followed by a heating zone in the rotary pulse welding device, in which at least one welding blade is configured to heat this joint zone, while the pressure application zone before heating and the heating zone are stationary with respect to the rotation of the roller, while the speed of rotation of the roller is adjustable with respect to the material to be joined, so that at least one welding knife is movable with a substantially such the same speed as the material to be joined while applying pressure to the joint area by means of the welding knife.

The term "comprising" as used herein means "consisting at least in part of". When interpreting each statement in this specification that includes the term "comprising", it should be understood that there may also be elements other than the one or those preceded by this term. Related terms such as "comprise" and "comprises" should be construed in the same way.

In an embodiment, the roller is rotatable through a post-heat pressure application zone provided in a rotary pulse welder that allows pressure to be applied to the material to be joined by the at least one welding blade.

In an embodiment, the pressure application zone prior to heating is immediately adjacent to the heating zone.

In an embodiment, the zone of application of pressure after heating is directly adjacent to the zone of heating.

In an embodiment, the heating zone is a heating and pressure zone.

In an embodiment, the body of the welding knife is or contains an insulating material.

In an embodiment, the heating element extends substantially along the entire length of the main body of the welding blade.

In an embodiment, the heating element is or contains a conductive material.

In an embodiment, the roller body has a plurality of slots, with each slot holding one of the welding blades.

In an embodiment, at least one welding knife has a longitudinal axis that is substantially parallel to the axis of the roller.

In an embodiment, at least one welding knife has a longitudinal axis that is not parallel to the roller axis.

In an embodiment, each welding blade has a body and a selectively heated heating element extending along at least a portion of the length of the body of the welding knife.

In an embodiment, the roller axle is a fixed axle.

According to a second aspect of the invention, there is provided a vertical forming and filling machine comprising: a drive system for driving at least two sheets of joinable material that are welded together continuously along their opposite edges by the machine; a filling product supply device for introducing a filling product between two sheets of bondable material; and a rotary pulse welder according to any one of the preceding claims, wherein the rotary pulse welder is configured to form transverse seals in the at least two sheets of joinable material to form sealed containers with the filling product.

In an embodiment, the vertical forming and filling machine further comprises two cylindrical rollers for receiving sheets of jointable material and for forming two continuous spaced longitudinal welds along opposite edges of sheets of jointable material.

In an embodiment, the cylindrical rollers are arranged to bring sheets of joinable material to the rotary pulse sealer at an angle of approximately 90° relative to the horizontal plane.

In an embodiment, the rotary pulse welder is driven such that the welding knife forming the weld moves at substantially the same speed as the jointable material being welded.

According to a third aspect of the invention, there is provided a process for forming packages containing loose or flowable material, comprising:

a) continuous supply of at least two sheets of material, amenable to connection, between which there is a loose or fluid material;

b) applying pressure to the transverse joint zone of the material to be jointed to force loose or fluid material out of the transverse joint zone; And

c) heating the transverse zone of the joint to form a weld,

wherein steps b and c are performed by means of a rotary pulse welder;

moreover, by means of a tensioned belt, it is possible to supply a material that can be connected to a rotary device for pulse welding; And

wherein the speed of rotation of the rotary pulse welder with respect to the material to be joined is adjustable so that the rotary pulse welder moves at substantially the same speed as the material to be jointed during application of pressure to the joint zone by means of rotary device for pulse welding.

In an embodiment, the method further includes:

d) applying pressure to the transverse joint zone after step c.

In an embodiment, step d includes allowing heat to be dissipated from the transverse joint zone.

In an embodiment, step c includes the simultaneous application of pressure and heat to the transverse joint zone.

In an embodiment, step c is performed immediately after step b.

In an embodiment, step d is performed immediately after step c.

In an embodiment, the transverse bonding zone extends transversely across the entire width of the data of at least two sheets of bondable material.

In an embodiment, the method further includes the step of providing of a rotary pulse welder, wherein the rotary pulse welder comprises a roller rotatable about an axis, the roller having a roller body and a plurality of welding knives extending radially outward from the roller and spaced apart around the body roller, wherein at least one of the welding knives has a main part and is made with the possibility of selective heating, a heating element passing along at least part of the length of the main part of the welding knife, while the roller is made rotatable through the existing in the rotary pulse welder, a pressure application zone before heating, in which at least one welding knife is configured to apply pressure to the joint zone of the material to be joined, and followed by the heating zone present in the rotary pulse welder, in which , at least one welding knife is configured to heat this connection zone, while the pressure application zone before heating and the heating zone are stationary with respect to the rotation of the roller.

In an embodiment, the rotary pulse welder performs step d.

In an embodiment, step c includes selectively applying current to the welding knife heating element.

According to a fourth aspect of the invention, there is provided a package containing a particulate or flowable material obtained by the method according to the third aspect.

In accordance with an aspect of the invention, there is provided a rotary paddle pulse welding apparatus which is designed to form an intermittent joint in a material to be joined and which comprises a roller rotatable about an axis; a plurality of welding knives extending radially outward from the roller and located at a distance from each other around the roller, wherein at least one of the welding knives is configured to selectively excite current during part of the rotation of the roller for temporary heating, at least , one of this welding blade, wherein at least one welding blade is configured to apply pressure to the area of the material to be joined during the part of the revolution that immediately precedes the part of the revolution during which this at least one welding knife.

In an embodiment, each welding blade is configured to apply pressure during the portion of the revolution immediately following the portion of the revolution during which the at least one welding blade is heated.

In an embodiment, at least one welding blade comprises a main body of the welding blade and a heating element extending along at least part of the length of the main body of the welding blade.

In an embodiment, the heating element extends substantially along the entire length of the main body of the welding blade.

In an embodiment, the roller is provided with a plurality of slots configured to receive respective welding blades therein, the slots being shaped such that the weld blades extend radially from the roller.

In an embodiment, at least one of the slots is substantially parallel to an axis about which the roller can rotate.

In an embodiment, at least one of the slots is located such that it is not parallel to an axis about which the roller can rotate.

In an embodiment, at least one of the slots is shaped such that it is not parallel to an axis about which the roller can rotate.

According to a further aspect of the invention, the vertical forming and filling machine comprises a drive system for driving at least two sheets of joinable material that are welded together continuously along their opposite edges by the machine; a filling product supply device for introducing a filling product between two sheets of material to be joined; a rotary vane device for pulse welding for forming sealed containers with a filling product, made with the possibility of applying pressure to the area to be joined during the part of the revolution that immediately precedes that part of the revolution, during which the rotary vane device for pulse welding supplies heat to form a joint.

In an embodiment, the rotary blade pulse welder is configured to apply pressure during the part of the revolution immediately following the portion of the revolution during which the rotary blade pulse welder supplies heat to form a joint.

In an embodiment, the rotary blade pulse welding apparatus is configured to receive sheets of joinable material, between which the filler material is contained, at an angle relative to the horizontal plane greater than 0°.

In an embodiment, the rotary paddle pulse welder is driven at substantially the same speed as the jointable material being welded.

In accordance with a further aspect of the invention, a method for forming packages of loose or flowable material includes providing a drive system configured to drive at least two sheets of joinable material; continuously welding together the first edge and the second edge of the sheets of joinable material; introducing a fluid material between two sheets of bondable material; security a rotary vane pulse welder configured to apply pressure to the area to be joined during the part of the revolution immediately preceding the portion of the revolution during which the rotary vane pulse welder supplies heat to form the joint.

In accordance with one aspect, the invention includes several steps. The relationship of one or more of these steps to each of the other steps, the apparatus in which the structural elements are implemented, and the combinations of elements and arrangement of components that are configured to affect such steps are exemplified in the detailed disclosure below.

It is intended that reference to a range of numbers disclosed herein (eg, 1-10) also includes reference to all rational numbers in that range (eg, 1, 1.1, 2, 3, 3.9, 4, 5, 6 , 6.5, 7, 8, 9, and 10), as well as any range of rational numbers within that range (for example, 2-8, 1.5-5.5, and 3.1-4.7), and therefore, all subranges of all ranges expressly disclosed herein are explicitly disclosed therein. These numbers are only examples of what is specifically provided, and all possible combinations of numerical values between the smallest value and the largest value given should be considered similarly as expressly given in this application.

Many design changes and widely varying embodiments and uses of the invention will be self-evident to those skilled in the art to which the invention pertains without departing from the scope of the invention as defined in the appended claims. The disclosure and descriptions herein are illustrative only and are intended to be non-limiting in any sense. In cases where specific integers/objects are mentioned in this document that have known equivalents in the technical field to which this invention pertains, it is intended that such known equivalents be included in this document as if they were given separately.

In the context of this document in English, the element “s” following a noun denotes the plural and/or singular form of that noun.

In the context of this document, the expression "and/or" means "and" or "or", or both "and" and "or" in cases where the context allows it.

The invention consists of what has been set forth above, and also provides structures for which only examples are given below.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the rotary blade pulse welding apparatus will be described below by way of example only, with reference to the accompanying drawings, in which:

1 shows a schematic view of a vertical forming and filling machine including a rotary paddle pulse sealer;

Fig. 2 shows a roller of an exemplary rotary vane pulse welding machine;

3 shows the welding knife of an exemplary rotary bladed pulse welding device; And

4 shows an alternative design of a drive system for a vertical forming and filling machine.

DETAILED DESCRIPTION

1 shows a schematic representation of a vertically forming and filling machine 100 for making packages 105 with a free-flowing or flowable filling product 110. The vertically forming and filling machine 100 includes a drive system 115 for driving the movement of at least two sheets 120, 121 of joinable material that are welded together continuously along their opposite edges by the machine 100. The drive system operates continuously. The vertical forming and filling machine 100 also has a filling product supply device 125 for introducing the filling product 110 between two sheets 120, 121 bondable material. The vertical forming and filling machine 100 also has a rotary pulse welding device 130 . The rotary pulse welder 130 is configured to form transverse welds in these at least two sheets of joinable material to form sealed containers 135 with filling product 110. The vertical forming and filling machine also has a cutting station 140 , designed to separate sealed containers 135 into separate packages 105.

The vertical forming and filling machine 100 is configured to pack loose or flowable material or product such as liquids or loose powders. The size of the machine and/or machine components can be adapted to produce packages of any size. In an embodiment, machine 100 is configured to produce packages having a volume of about 2 ml or about 5 ml. In another embodiment, the machine 100 is configured to produce packages having a volume of approximately 1 liter or more. Machine 100 can be configured to produce packages having any other suitable volume, such as about 10 ml, about 20 ml, about 50 ml, about 75 ml, about 100 ml, about 200 ml, about 500 ml, about 750 ml. ml or approximately 2 liters.

Free-flowing or flowable materials include liquids, creams, lotions, gels, pastes, powders, wetted powders, particulate materials, sauces, beverages, sunscreens, lubricants, paints, greases, oils, adhesives, resins, drugs, pharmaceuticals. drugs, etc.

The rotary pulse welder 130 provides a series of discrete joints in the bondable material 120, 121. The rotary pulse welder 130 has a roller 145 rotatable about an axis. In the embodiment shown, the roller axle is a fixed axle. The roller 145 has a roller body 155 and a plurality of welding knives 150. The welding knives 150 extend radially outward from the roller 145 and are spaced apart around the roller body 155. In the embodiment shown, the welding blades 150 extend in the axial direction along substantially the entire length of the roller 145 in the axial direction.

At least one of the welding blades 150 has a main body 175 and a selectively heated heating element 180 extending along at least a portion of the length of the main body 175 of the welding knife. In the embodiment shown, each welding knife 150 has a body 175 and a selectively heated heating element 180 extending along at least a portion of the length of the body 175 of the welding knife.

Roller 145 is rotatable through a pre-heating pressure application zone, or a zone corresponding to part A of the turn, in which pressure can be applied to the joint zone 154 of the material 120, 121, amenable to connection, by means of this at least one welding knife 150. The pre-heating pressure application zone A is followed by a heating zone or zone corresponding to part B of the turn, in which the connection zone 154 can be heated by this at least one welding knife 150. The pre-heating pressure application zone A and the heating zone B are fixed in relation to the rotation of the roller 145.

In the embodiment shown, roller 145 is rotatable through a post-heating pressure application zone, or zone corresponding to rotation portion C, in which pressure can be applied to the material to be joined by the at least one welding blade 150. Zone C post-heat pressure application is stationary with respect to the rotation of roller 145. In an alternative embodiment, the rotary pulse welder 130 may not have a post-heat pressure application zone C, and the roller may only rotate through a pre-heat pressure application zone followed by zone B heating.

The rotary pulse welder 130 may be referred to as the rotary paddle pulse welder 130 . The "blades" of the rotary pulse pulse welder are the welding blades 150. The welding blades 150 function like blades to expel the filler product from the joint area, as will be described in more detail below.

The heating element 180 is configured to be heated by selectively applying current to the heating element 180 while passing through the heating zone B as the rotary pulse welding device 130 rotates. In an embodiment, the heating element 180 of each welding knife 150 is configured to be heated by selectively applying current to the heating element 180. The selectively applied current can be described as a pulsed current.

In a preferred embodiment, two sheets 120, 121 of joinable material are welded together continuously along their opposite edges to form two substantially parallel longitudinal connecting portions. The bondable material may be polyethylene or any other heat sealable or thermally bondable material. The longitudinal connecting portions may be formed by any suitable process, such as a conventional continuous heat seal process. In the embodiment shown, sheets 120, 121 of bondable material enter the area between two cylindrical rollers 151, 152. One roller 152 of the cylindrical rollers has heated portions at both ends (not illustrated) that provide heat to the edges of the sheets 120, 121 material, amenable to connection, to form the longitudinal connecting parts. Cylindrical rollers 151, 152 form two continuous spaced longitudinal welds along opposite edges of sheets 120, 121 of material to be joined. Filling product 110 is introduced between the longitudinal connecting parts.

In an alternative embodiment, the sheet of bondable material is folded in half and one longitudinal joint portion is formed at the open edges of the sheet. The filling product 110 is inserted between the longitudinal fitting and the fold. In a further alternative embodiment, the filling product 110 is introduced into the pipe of a jointable material. A pipe of joinable material may not have any longitudinal fittings.

The drive system 115 includes a belt 116 that drives the jointable material 120, 121 towards the rotary paddle pulse welder 130 at a substantially constant speed. The belt is held under tension by a cylindrical roller 151 and two belt (lower) pulleys 157, 158 in combination with a rotary pulse welder 130. One or more of the rollers/pulleys 151, 157, 158 may be a drive roller/pulley that drives the belt 116. The sheets 120, 121 are fed to the rotary paddle pulse welder 130 via the drive system 115.

In the embodiment shown in figure 1, the belt pulleys 157, 158 are located below the cylindrical roller 151. The belt pulleys 157, 158 are located at essentially the same height. The drive system 115 is of a substantially L-shaped design, with the rotary pulse welder 130 located in the "letter" L bend zone. in contact with the bondable material 120, 121.

4 shows an alternative design of the drive system 1115. Drive system 1115 is the same as drive system 115 except as described below. Similar components are identified by like reference numerals incremented by 1000. In this embodiment, one belt pulley 1158 of belt pulleys is positioned below the cylindrical roller 1151 substantially in line with the cylindrical roller 1151 such that the rotary pulse welder 1130 acts on the essentially the vertical surface of the belt. This design provides a relatively short part of the rotation of the rotary pulse welder during which the welding blade 1150 is in contact with the material 1120, 1121, amenable to connection. This design may be suitable for applications requiring short seal times and may allow for very fast formation of packages.

In other embodiments, the relative position of the belt pulleys may be selected or specified depending on the required welding time. For example, the belt pulleys may be arranged such that the belt is in a U-shape or V-shape. With this configuration, the welding time can be increased compared to the welding time of the illustrated embodiments because the belt will move around the roller for more time.

In the embodiments shown in FIGS. 1 and 4, cylindrical rollers 151, 152 are positioned to bring sheets 120, 121 of joinable material to rotary pulse welder 130 in their substantially vertical orientation (at an angle relative to horizontal plane of approximately 90°). In alternative embodiments, the sheets 120, 121 of the jointable material are brought in at any angle that allows the filling product to be lowered towards the rotary paddle 130 for pulsed gravity welding. In an embodiment, the angle relative to the horizontal plane is greater than 0°. In an embodiment, the angle relative to the horizontal plane is less than 90°. For example, sheets 120, 121 of bondable material may be approached at an angle relative to the horizontal plane of about 85°, about 80°, about 70°, about 60°, about 45°, about 30°, or about 15°.

In an embodiment, at least one of the sheets 120, 121 of joinable material is modified prior to welding to another sheet of joinable material 120, 121, such as by adding registration marks to facilitate synchronization of machine operations. In an embodiment, one of the sheets 120, 121 of the bondable material is provided with a score line and/or another line of weakness to facilitate controlled tearing of at least one of the layers of the package 105 prior to dispensing the contents of the package 105. The line of weakness may be zigzag. . Exemplary package designs are disclosed in NZ 547925, which is incorporated herein by reference.

When the welding blade 150 initially comes into contact with the bondable material 120, 121, the welding blade 150 applies pressure to the bondable material 120, 121 in the entire pre-heat pressure application zone A, which corresponds to a portion of the revolution of the roller 145. Welding blade 150 causes pressure to be applied in a substantially transverse direction over the entire width of the data of at least two sheets 120, 121 of material to be joined. The pressure from the welding knife 150 forces the filling product 110 out of the joint area 154 . The pressure from the welding blade 150 provides a containment space 156 between the welding blade 150 and an adjacent welding blade 150 further along the path of rotation.

The joint zone 154 extends transversely over the data width of at least two sheets 120, 121 of jointable material. The connection zone 154 extends at an angle relative to the longitudinal connecting portions of approximately 90°. In alternative embodiments, the joint zone 154 extends between the longitudinal connecting portions at any suitable angle, for example, about 75°, about 80°, about 85°, about 95°, about 100°, or about 105°.

Then, a pulsed current is applied to the heating element 180 of the welding blade 150 during the part of the rotation of the roller 145 that corresponds to the heating zone B to heat the welding blade 150. The heat from the welding blade 150 causes the formation of a transverse connecting part in the material 120, 121, amenable to the connection. In the embodiment shown, the pressure application zone A before heating is directly adjacent to the heating zone B.

In other words, the pre-heating pressure application zone A in which the welding blade 150 applies pressure to the material zone to be joined immediately precedes the heating zone B in which the welding blade 150 is heated to form a joint.

In an alternative embodiment, there may be a gap between the pre-heating pressure application zone A and the heating zone B.

In an embodiment, heating zone B is a heating and pressure zone. In a preferred embodiment, more pressure is applied in the heating zone B than in the pressure application zone A before heating. In an alternative embodiment, less pressure is applied in heating zone B than in preheating pressure application zone A.

After switching off the pulsed current, the joint is cooled by pressure from the side of the welding blade 150 during the part of the rotation of the roller 145 that corresponds to the pressure application zone C after heating. In the embodiment shown, the pressure application zone C after heating is immediately adjacent to the heating zone B.

In other words, the post-heating pressure application zone C in which the joint is cooled under pressure from the welding blade 150 immediately follows the heating zone B in which the welding blade 150 is heated to form the joint.

In an alternative embodiment, the application of pressure after heating, it may not immediately follow the heating zone. For example, another step or process may be provided between the heating zone B and the post-heating pressure application zone C.

In an embodiment, the heating element is formed from a material that is rapidly cooled, so that the bondable material is cooled to a temperature that is below the melting point of the bondable material in the case where current is no longer applied. This allows heat to be dissipated in the pressure application zone C after heating. Heat can be dissipated in many different directions. For example, heat can be dissipated into the filling product 110, the bondable material 120, 121, and the environment.

In an embodiment, the welding knives 150 include a cooling system, such as a water cooling system, to promote heat dissipation.

The application of pressure by the welding knife 150 prior to heating the jointable material 120, 121 ensures that the filling product 110 is removed from the zone to be jointed before the joint is formed. This provides a high quality joint that is free or at least substantially free of filler product particles 110. Allowing the joint to cool while still under pressure from the welding knife 150 ensures proper curing of the joint and further aids in obtaining high quality weld.

Placing the rotary paddle pulse welder 130 below the feed zone of the vertically or at an angled filling product 110 as shown in FIG. gaps. This is advantageous in some applications, for example in food packaging, the absence of air gaps can increase the shelf life of the food product.

2 shows an isometric view of an illustrative roller 145. The roller includes a roller housing 155. The roller body 155 is electrically isolated from the welding knives 150. In an embodiment, the roller body 155 is made of an insulating material, such as a polymeric material such as high density polyethylene. In an alternative embodiment, the roller body 155 is at least partially covered with an insulating material. The roller body 155 has an axle receiving hole 160 (not shown) and a plurality of slots 165, with each slot 165 holding one of the welding blades 150. One welding blade 150 is shown mounted in the slot 165.

In an embodiment, the slots 165 are slightly narrower than the welding blades 150 so that the weld blades 150 can be held in the slots 165 by an interference fit. In an embodiment, slots 165 include electrodes for contact with electrodes 185, 186 of welding knives 150. The electrodes are made of tinned copper or any other suitable conductive material.

The roller axis 145 is driven, for example, by a servomotor. In an embodiment, the control system adjusts the speed of roller 145 to ensure that the transverse fittings "align" correctly with the alignment marks on the material to be joined.

Rotation of the roller 145 ensures that the welding blade 150 that forms the weld will move at substantially the same speed as the jointable material 120, 121 that is being welded. This guarantees the formation of a high quality weld. If the roller 145 were not driven and instead was free to rotate, there would be the possibility of the welding blades 150 slipping against the joinable material 120, 121, resulting in a poor quality weld. In addition, it would not be possible to precisely align the transverse connecting parts by using the control system.

The welding blades 150 extend outward from the roller 145 to form a gap in which individual containers 135 with the filling product 110 are placed. In the embodiment shown, the boundaries of the gap are defined by substantially flat portions 170 of the roller 145 that extend between the welding knives 150.

In alternative embodiments, the roller 145 may be of any other suitable shape that allows the individual containers 135 of the filling product 110 to be accommodated. For example, portions 170 of the roller 145 extending between the welding blades 150 may be convex or concave.

The distance between the outer surfaces of the welding blades 150 defines the longitudinal dimension of the packaging space 105. In the illustrated embodiment, the rotary pulsed blade welding apparatus 130 has eight welding blades 150 spaced approximately 40 mm apart in the radial direction.

In alternative embodiments, any suitable number of sealing knives may be used, with any suitable spacing between them, to provide the desired package sizes. In the embodiment shown, the welding blades 150 are spaced equidistantly around the roller 145. At least one of the welding blades 150 has a longitudinal axis that is substantially parallel to the axis of the roller. In the embodiment shown, all welding knives 150 have a longitudinal axis that is substantially parallel to the axis of the roller. The construction and arrangement of the sealing knives 150 shown in the figures enables the manufacture of packages that have a transverse joint portion that is substantially perpendicular to the longitudinal joint portions.

In an alternative embodiment, the welding knives 150 are spaced unequally apart.

In an alternative embodiment, at least one of the welding knives has a longitudinal axis that is not parallel to the axis of the roller. This can be achieved, for example, by providing at least one groove which is located so that it is not parallel to the axis around which the roller can rotate. In an embodiment, the welding blades 150 are angled so that they form transverse fittings that are not perpendicular to the longitudinal fittings.

In an alternative embodiment, the welding knives are configured to form a transverse connecting portion having a complex shape. For example, the welding knives may be shaped to form a transverse connecting portion having a curved shape. This can be achieved, for example, by providing at least one groove which is shaped so that it is not parallel to the axis about which the roller can rotate.

3 shows an exemplary welding knife 150. Welding knife 150 includes a welding knife body 175, a heating element 180, and electrodes 185, 186.

The main body 175 of the welding knife is configured to be inserted into the groove 165 of the roller 145. The welding knives 150 are installed in the grooves 165 using any suitable method. In the embodiment shown, the welding knife body 175 has a substantially rectangular cross-section that allows it to be installed with an interference fit in the groove 165 of the roller 145. In alternative embodiments, the welding knife body 175 and the roller grooves 165 are shaped such that the main the welding blade portion 175 is held when the welding blade 150 is pushed into the groove 165 in the axial direction.

The main body 175 of the welding knife is or contains an insulating material. The main body 175 of the welding blade is made of a material of suitable strength that can withstand both pressure applied from the side of the welding blade 150 to the material 120, 121, amenable to connection, and heat from the heating element 180. In the embodiment, the main body 175 of the welding blade is formed from polyetheretherketone (PEEK). In an alternative embodiment, the main body 175 of the welding blade is formed from a conductive material, such as an aluminum alloy, which is at least partially covered with an insulating material. In a further alternative embodiment, the main body 175 of the welding knife is or contains a ceramic material.

The heating element 180 extends essentially along the entire length of the main body 175 of the welding knife and is bent at the ends of the main body 175 of the welding knife. The heating element 180 is or contains a conductive material. In an exemplary embodiment, heating element 180 is made from a chromium-nickel alloy. For example, heating element 180 may be made from a nickel-chromium alloy containing about 60% nickel, about 16% chromium, and about 24% iron. The heating element may be made from any other suitable heating element material. In the embodiment shown in the figures, the heating element 180 extends substantially along the entire length of the main body 175 of the welding knife.

In an alternative embodiment in which the main body 175 of the welding blade is or contains ceramic material, the heating element 180 may include a thin layer of conductive material, such as a layer of conductive particles. The particles may look like sand. The conductive particles may be a metal. A thin layer of conductive material may be embedded in the main body 175 of the welding blade. A thin layer of conductive material may be covered with a thin layer of glass ceramic.

The electrodes 185, 186 cover the heating element 180 at the ends of the welding knife body 175 and allow electrical current to be supplied to the heating element 180. The electrodes are made of tinned copper or any other material with suitable conductivity. The current may be applied to the electrodes by slip rings or by any other suitable means.

Next, a method for forming packages containing particulate or flowable material will be described. The method includes step a, which is for continuously supplying at least two sheets 120, 121 of a jointable material, between which there is a loose or flowable material 110. the next step is performed, namely step b, which involves applying pressure to the transverse joint zone 154 of the jointable material 120, 121. The application of pressure to the transverse zone 154 of the connection ensures the displacement of loose or fluid material 110 from the zone of the connection.

The next step, namely step c, includes heating the transverse zone 154 of the joint to form a weld. In a preferred method, step c includes the simultaneous application of pressure and heat to the transverse joint zone.

Step c includes selectively applying current to the heating element 180 of the welding knife 150 (in other words, applying a pulsed current). The welding knife 150 has electrodes 185, 186 which cover the heating element 180 at the ends of the main body 175 of the welding knife. The pulsed current is applied to the electrodes 185, 186 of the welding knife by means of electrodes mounted in the grooves 165 of the roller 145. The electrodes 185, 186 are in electrical communication with the slip ring, which is electrically charged during the part of the rotation of the roller 145 that corresponds to the heating zone B for selective feeding current to the heating element 180. In an alternative embodiment, the pulsed current can be applied directly to the electrodes 185, 186 of the welding knife.

The power delivered during the pulse may vary depending on the application. In an exemplary embodiment, power corresponding to approximately 10V, 80A is applied for approximately 150-250 milliseconds. The applied power and/or pulse duration may vary depending on the thickness and properties of the material to be joined. For example, a pulse duration of approximately 50 ms may be sufficient to obtain a good connection in some applications. In alternative embodiments, any suitable pulse width may be used, such as about 60 ms, about 80 ms, about 100 ms, about 120 ms, about 200 ms, or about 300 ms.

The heating element 180 is heated to approximately 300° C. when a pulsed current is applied. In other embodiments, the heating element is heated to any other appropriate temperatures, such as, for example, about 200°, about 220°, about 250°, about 270°, about 290°, about 310°, about 330°, or about 350°. The temperature of the heating element may be selected depending on the properties of the sheets 120, 121 of the material to be bonded. The temperature of the heating element 180 may be significantly higher than the melting point of the material to be bonded. For example, the temperature of the heating element 180 may be approximately twice the melting point of the material to be bonded. The relatively high temperature of the heating element 180 allows sufficient heat to penetrate into the joint area to create a weld within a relatively short pulse duration. A higher temperature of the heating element 180 can be used when the sheets 120, 121 of the bondable material are thicker.

In a preferred embodiment, the method further includes step d, which includes applying pressure to the transverse joint zone 154 after the step of heating the transverse joint zone. This step takes place during the part of the revolution of the roller, which corresponds to the zone C of the application of pressure after heating. The application of pressure after the c heating step may assist in proper curing of the joint. In an alternative embodiment, the method may not include step d.

Either during step d or before step d, heat is no longer supplied to the transverse joint zone. Heat is no longer supplied by interrupting the pulsed current. Accordingly, during step d, heat can be dissipated from the transverse joint zone. For example, heat may be dissipated into the particulate or fluid material 110, the bondable material 120, 121, and the environment.

The heating element 180 cools down to a temperature of less than 120° as heat is dissipated. The heating element 180 may be cooled to any appropriate temperature depending on the material being bonded. For example, the heating element may be cooled to about 60°, about 80°, about 100°, about 140°, or about 160°.

Step d is preferably performed immediately after step c. In an alternative embodiment, there may be a gap between the execution of step c and the execution of step d.

In the preferred method, the pressure is applied continuously in steps b, c and d. In an embodiment, the amount of pressure applied increases during step b and reaches a maximum during step c. The amount of pressure applied is then reduced during step d. In an alternative embodiment, the amount of pressure applied may be relatively constant throughout a significant portion of steps b, c and d. In alternative embodiments, step c may include applying the same pressure as step b or less pressure than step b. In a preferred embodiment, step c includes applying more pressure than step b. In alternative embodiments, step c includes applying the same pressure as step d or less pressure than step d.

The method is preferably performed using a rotary pulse welder 130 . In the preferred method, the rotary pulse welder 130 performs steps b, c and d. In an alternative embodiment, the rotary pulse welder 130 may perform steps b and c rather than step d. Stage b corresponds to the pressure application zone A before heating during rotation of the roller. Step c corresponds to heating zone B during rotation of the roller. Stage d corresponds to the pressure application zone C after heating during rotation of the roller.

In an exemplary embodiment, pressure is applied to pressure application zone A prior to heating for approximately 400 milliseconds. The pressure may be applied in the preheating pressure application zone A for any appropriate amount of time. The optimal amount of time may vary for different bulk or flowable materials. For example, pressure may be applied for about 50 milliseconds, about 60 milliseconds, about 80 milliseconds, about 100 milliseconds, about 150 milliseconds, about 200 milliseconds, about 250 milliseconds, about 300 milliseconds, about 350 milliseconds, about 450 milliseconds, about 500 milliseconds. milliseconds, approximately 550 milliseconds, or approximately 600 milliseconds.

In an exemplary embodiment, pressure is applied to pressure application zone C after heating for approximately 400 milliseconds. The pressure may be applied in the pressure application zone C after heating for any appropriate amount of time. The optimal amount of time may vary for different materials. For example, pressure may be applied for about 50 milliseconds, about 60 milliseconds, about 80 milliseconds, about 100 milliseconds, about 150 milliseconds, about 200 milliseconds, about 250 milliseconds, about 300 milliseconds, about 350 milliseconds, about 450 milliseconds, about 500 milliseconds. milliseconds, approximately 550 milliseconds, or approximately 600 milliseconds.

The rotational speed of the roller 145 and/or the moments and location of the pulsed current are controlled by the control system. In an exemplary embodiment, the pulsed current is applied at the time of rotation of roller 145 corresponding to the start of heating zone B. In an exemplary embodiment, the pulsed current is applied during that part of the rotation of the rotary bladed pulse welding apparatus 130 when maximum pressure is applied to the material 120, 121 to be joined by the welding knife 150. The location and extent of the part of the rotation where the supply is impulse current, can be adjusted by the control system. For example, one revolution of roller 145 is divided into a number of counts. A sensor cooperating with the roller axis 145 determines the nominal starting point for the revolution. The control system supplies current to each welding blade 150 at a different number of counts, so that the current is initially applied to each welding blade 150 at the turning point of roller 145 corresponding to the start of heating zone B. Current is supplied to each welding knife 150 for a user-specified time.

Preferred embodiments of the invention have been described by way of example only, and modifications may be made without departing from the scope of the invention.

Claims (44)

1. A rotary pulse welder designed to form a series of discrete joints in a bondable material, the rotary pulse welder comprising: a roller rotatable about an axis, wherein the roller has a roller body and a plurality of welding knives extending radially outward from the roller and spaced apart around the roller body, wherein at least one of the welding knives has a main body and made with the possibility of selective heating of the heating element, passing along at least part of the length of the main part of the welding knife; a tensioned belt for supplying a bondable material to the roller; wherein the roller is rotatable through a pre-heating pressure application zone in the device, in which at least one welding knife is configured to apply pressure to the connection zone of the material to be joined, and followed by a heating zone in the device, in which at least at least one welding knife is made with the possibility of heating the joint zone, while the pressure application zone before heating and the heating zone are stationary with respect to the rotation of the roller, wherein the speed of rotation of the roller with respect to the jointable material during application of pressure to the joint zone by the welding blade is adjustable so that at least one welding blade moves at substantially the same speed as the jointable material. 2. Apparatus according to claim 1, wherein the roller is rotatable through the post-heating pressure application zone of the apparatus, wherein at least one welding blade is operable to apply pressure to the material to be joined. 3. Apparatus according to any one of claims 1, 2, wherein the zone of application of pressure before heating is directly adjacent to the zone of heating. 4. Device according to any one of claims 2, 3, in which the zone of application of pressure after heating is directly adjacent to the zone of heating. 5. An apparatus according to any one of claims 1 to 4, wherein the heating zone is a heating and pressure application zone. 6. Apparatus according to any one of claims 1 to 5, wherein the body of the welding knife is or contains an insulating material. 7. Apparatus according to any one of claims 1 to 6, wherein the heating element extends substantially along the entire length of the body of the welding blade. 8. An apparatus according to any one of claims 1 to 7, wherein the heating element is or comprises a conductive material. 9. An apparatus according to any one of claims 1 to 8, wherein the roller body has a plurality of slots, each slot being configured to hold one of the welding blades. 10. An apparatus according to any one of claims 1 to 9, wherein at least one welding blade has a longitudinal axis which is substantially parallel to the axis of the roller. 11. An apparatus according to any one of claims 1 to 10, wherein at least one welding blade has a longitudinal axis which is not parallel to the axis of the roller. 12. An apparatus according to any one of claims 1 to 11, wherein each welding blade has a body and a selectively heated heating element extending along at least a portion of the length of the body of the welding knife. 13. An apparatus according to any one of claims 1 to 12, wherein the roller axle is a fixed axle. 14. Machine for forming and filling in the vertical direction, made with the possibility of packaging bulk or fluid material or product, containing: a drive system for driving at least two sheets of joinable material that are welded together continuously along their opposite edges by the machine; a filling product supply device for introducing a filling product between two sheets of bondable material; And a rotary pulse welding apparatus according to any one of claims 1 to 13, wherein the apparatus is configured to form transverse welds in at least two sheets of joinable material to form sealed containers with the filling product. 15. The machine of claim 14, further comprising two cylindrical rollers for receiving sheets of jointable material and for forming two continuous spaced longitudinal welds along opposite edges of the jointable material sheets. 16. A machine as claimed in claim 15, wherein the cylindrical rollers are positioned to bring sheets of joinable material to the rotary pulse welder at an angle of approximately 90° relative to a horizontal plane. 17. A machine according to any one of claims 14 to 16, wherein the rotary pulse welding apparatus is actuated such that the welding blade forming the weld moves at substantially the same speed as the jointable material being welded. 18. A method for the formation of packages containing loose or fluid material, including: a) continuous supply of at least two sheets of connectable material, between which there is a loose or fluid material; b) applying pressure to the transverse joint zone of the jointable material to force loose or fluid material out of the transverse joint zone; And c) heating the transverse zone of the joint to form a weld, wherein steps b and c are performed by means of a rotary pulse welder; wherein the bondable material is fed to the device by means of a tensioned belt; And wherein the speed of rotation of the device with respect to the material during the application of pressure to the connection zone by the device is adjustable so that the device moves at substantially the same speed as the material to be joined. 19. The method of claim 18, further comprising: d) applying pressure to the transverse joint zone after step c). 20. The method of claim 19, wherein step d) includes allowing heat to be dissipated from the transverse joint zone. 21. The method according to any one of claims 18-20, wherein step c) comprises simultaneously applying pressure and applying heat to the transverse joint zone. 22. The method according to any one of claims 18 to 21, wherein step c) is carried out immediately after step b). 23. The method according to any one of claims 19 to 22, wherein step d) is carried out immediately after step c). 24. A method according to any one of claims 18 to 23, wherein the transverse bonding zone extends transversely over the entire width of at least two sheets of bondable material. 25. The method according to any one of claims 18-24, further comprising the step of: ensure a rotary device for pulsed welding, wherein the device comprises a roller configured to rotate around an axis, wherein the roller has a roller body and a plurality of welding knives extending radially outward from the roller and located at a distance from each other around the roller body, wherein at least one of the welding knives has a main part and a heating element made with the possibility of selective heating, passing along at least part of the length of the main part of the welding knife, wherein the roller is rotatable through a pre-heating pressure application zone in the device, in which at least one welding knife is configured to apply pressure to the connection zone of the material to be joined, and followed by a heating zone in the device, in which at least at least one welding knife is configured to heat the joint zone, while the pressure application zone before heating and the heating zone are stationary with respect to the rotation of the roller. 26. The method of claim 25, wherein the rotary pulse welder performs step d). 27. The method according to any one of claims 25, 26, wherein step c) comprises selectively applying current to the heating element of the welding knife. 28. A package containing loose or flowable material obtained by the method according to any one of claims 18-27.

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