CN108883849B

CN108883849B - Method and apparatus for producing bags or pouches with multi-stage sealing

Info

Publication number: CN108883849B
Application number: CN201680081583.2A
Authority: CN
Inventors: C.卡姆斯; P.亨尼库特; C.弗里瓦尔特; M.克吕格尔; J.普拉兹
Original assignee: CMD Corp
Current assignee: CMD Corp
Priority date: 2015-12-10
Filing date: 2016-12-09
Publication date: 2021-07-16
Anticipated expiration: 2036-12-09
Also published as: CN108883849A

Abstract

A method and apparatus for forming a bag and/or pouch is disclosed. The seal and/or insert are extruded using a multi-stage sealer or extruder.

Description

Method and apparatus for producing bags or pouches with multi-stage sealing

Technical Field

The present disclosure relates generally to the field of making bags or pouches, and more particularly to the field of making bags or pouches using a multi-stage sealer.

Background

There are many known vertical bagging machines, and the invention will be explained in the context of a bagging machine such as CMD Stand-Up Pouch machine or those shown in U.S. Pat. Nos. 6976946, 7191575 and 7325379, and U.S. patent publications US-2014-0332138-A1 and US-2011-0207589-A1, respectively, which are incorporated by reference. One example of a prior art bag machine having a zipper extrusion section includes an unfolding or feeding section, followed by a forming or folding section, followed by a machine direction bottom seal and zipper flange seal section, followed by a zipper extrusion section, followed by a side seal section, followed by other processes such as cutting, perforating, etc. The film advances and stops and each segment operates on the film portion of that segment. Then, when the operation is completed, the film advances and each segment is operated again. Each operation has been performed on the film as it completes its path through the machine, thus creating a pocket.

Bag designs have become complex, e.g., having any of a number of features, including a closable zipper, an easy-open tear string, product protection ventilation, etc. These features are added with an insert material or a material different from and/or having a thickness different from the pouch or substrate. As used herein, an insert refers to a feature such as a closure (zipper, hook and loop, push-to-close, etc.), tear strip, vent, plug, valve, spout, strap, etc., that includes a material different from and/or has a thickness different from the material comprising the pouch or base.

Inserts such as zippers are typically provided as a continuous strip (or strips) that must be compressed (squeezed) and sealed to the bag. The portion of the zipper near the edge of the bag must be sealed to properly seal the bag. The prior art machines are costly to operate and often produce poor seals around the insert and/or take a long time.

Since the insert or zipper is thicker than the bag and comprises a different material, it is difficult to squeeze and seal the insert to the base. Creating a consistently strong seal requires a consistent sealing pressure across the length of the seal and the additional thickness of the insert material causes inconsistent pressure in the sealing area.

The prior art typically seals the zipper/bag edges by squeezing them with a modified sealer, known as a zipper squeeze or zipper squeeze sealer, or by ultrasonically heating them. Squeezing the zipper minimizes the sealing pressure differential along the length of the side seals. If the insert is not sufficiently compressed, the pressure will not be sufficient to create a seal between the bag bases that intersects the insert material. Figure 1 shows a cross-sectional view of a zipper insert 102 inserted between two

layers

104 and 106 of a bag base. Figure 2 shows the zipper insert and base after extrusion.

Pressing the insert directly from its original thickness to its final thickness in one step makes it more likely that the seal will break. Thus, prior art machines sometimes include two separate sealers/presses. The first sealer/squeezer squeezes the zipper mostly, and the second sealer/squeezer squeezes the zipper to the final desired thickness. Even with two conventional extrusion stations, the bag converter needs to run at a speed lower than desired to create a strong seal with the zipper material due to the seal breaking.

Pressing and sealing the insert requires heat, pressure and time. The heat source must have sufficient thermal mass to melt the insert material and sufficient rigidity to maintain its shape even at large compression pressures. Hot bars (sometimes referred to as sealing heads or rollers) are commonly used in the art. Most prior art bag machines use a continuous pressure system to press the insert material. These extrusion units are usually retrofits of a cross sealing head station. Pneumatic cylinders or springs are used to generate continuous pressure (constant or gradual) and smaller heaters and tools are used than cross sealers. This method is effective in flattening the insert, but may produce a broken seal and/or poor bond strength between the insert and the substrate and/or between the insert material. The sealing head can be driven with a servo motor and eccentric linkage, but this approach is more expensive than a continuous pressure system.

The continuous extrusion press systems of the prior art do not always provide consistent seal bond strength. The extrusion pressure is nominally constant, with slight variations, and is an uncontrolled open loop, and continuous extrusion forces generate and maintain shear and strain stresses. Shear stress is the force perpendicular to the compressive force and parallel to the plane created by the flow velocity difference. Strain is caused by intermolecular mechanical resistance and friction, and depends on pressure and temperature.

The extrusion rate and final head position are determined by balancing, and the head will stop when the extrusion pressure equals the shear resistance of the material. Therefore, the shear stress and intermolecular stress of the seal portion are much larger than desired. The crystalline segments of the polymer chains cannot unfold and relax to their new positions because the compressive force increases more intermolecular strain. If the amorphous segments are oriented in a direction that is not conducive to entanglement, the compressive force will maintain strain and prevent further entanglement. This means that the oriented amorphous segments do not entangle properly due to the continuous extrusion pressure and the stresses it generates, and the crystalline segments may spring back, causing shear on the seal.

The prior art extrusion systems have limited performance and are not optimized for seal strength and run rate. Running a lower squeeze pressure will improve sealing, but will require a longer cycle time, which can limit the operating rate of the machine. The cycling rate can be minimized at higher pressures, but at the expense of higher shear and strain, and lower seal bond strength.

Accordingly, a machine and method of making a pouch with an insert or making a pouch with a seal that can consistently and economically produce a high quality seal in a timely manner without excessive seal shear stress and intermolecular strain is desired.

Disclosure of Invention

In accordance with a first aspect of the present disclosure, a bag making machine has an insert pressing station with a multi-stage press that receives an insert and a base.

According to a second aspect of the present disclosure, a bag machine has an insert pressing station including a controller having at least two of a pre-press heating module, a controlled press module, and a press setting module including continuous operation.

According to a third aspect of the present disclosure, a method of making a bag includes feeding a base to an insert pressing station, feeding an insert to the insert pressing station, multi-stage pressing of the insert and the base, and forming a seal to create a bag.

According to a fourth aspect of the present disclosure, a method of making a bag includes feeding a base to an insert pressing station, feeding an insert to the insert pressing station, and controlling the insert pressing station to continuously provide at least two or three of pre-press heating, controlled pressing, and pressing settings of the insert and the base.

In one alternative, the insert pressing station includes a drum having a controller with two or all of a pre-press heating module, a controlled press module, and a press module that operate continuously without returning to a home position between their operations. A roller as used herein refers to a bar, plate, or other device used to form a seal or apply pressure and heat to a substrate and/or substrate and insert.

In another alternative, the insert pressing station includes a servomotor operably connected to move the multi-stage drum in response to the controller, and an eccentric linkage and/or screw-driven actuator is connected to the drum and the servomotor to translate movement of the servomotor into movement of the drum.

In another alternative, the eccentric linkage is effective between 175 degrees and 180 degrees from top dead center.

In one embodiment, the multi-stage press includes a heat source, but does not include an ultrasonic source, and/or the bag machine includes a second sealing station that forms a seal pattern to form the bag.

In various embodiments, the inserts are zipper strips, tear strips and vent strips, zipper strips that are pressed closed, hook and loop strips, tear strips, and plugs and valve strips.

In one alternative, the bag machine includes a second insert pressing station that receives the base and the insert.

In one embodiment, the bag includes a controller having a distance module.

Other principal features and advantages will become apparent to those skilled in the art upon review of the following drawings, detailed description, and appended claims.

Drawings

FIG. 1 is a cross-section of a zipper insert and bag base prior to compression/sealing;

FIG. 2 is a cross-section of a crushed/sealed zipper insert and bag base;

FIG. 3 illustrates the travel and eccentric motion of the eccentric linkage;

FIG. 4 illustrates travel and eccentric motion in the squeeze area of the eccentric linkage;

FIG. 5 shows a graph of a multi-stage crush;

FIG. 6 shows the insert after flow during preheating and extrusion;

FIG. 7 shows three polymers entangled in their chains;

FIG. 8 shows temperature versus depth into polyethylene for various residence times;

FIG. 9 is a block diagram of a bag machine;

FIG. 10 is a block diagram of a portion of a controller for a bag machine;

FIG. 11 is a sealing head, sealing bar or roller; and

FIG. 12 is a block diagram of a capsule making machine.

Before explaining at least one embodiment in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. Like reference numerals are used to designate like components.

Detailed Description

While the present disclosure will be illustrated with reference to particular embodiments, it should be understood first that the bag machine and method of making bags can be implemented in other designs, components and acts.

Generally, a method of making a bag includes a multi-stage extrusion of an insert and a machine for making a bag includes an insert extrusion section having a multi-stage extruder. The segment applies a multi-stage compression to compress/seal the insert in multiple stages. The multi-stage extrusion is performed by a single station. Additional extrusion stations may be used, but at least one station performs a multi-stage extrusion. The machine and the process can be according to the prior art, except for a multi-stage extrusion. A single station as used herein refers to a location where a seal is formed or partially formed without advancing the film to another location. Zipper presses of the prior art typically use multiple stations where the seal is partially formed at one station, then the film is advanced and the seal is completed at a second station. One embodiment provides multiple stages to seal the bag.

An insert pressing station as used herein refers to a station that applies energy to press the insert and substrate to seal the insert to the bag and/or the film used to form the bag. The insert extrusion section (or station) is a type of sealing section. Multi-stage extrusion as used herein refers to extrusion performed by a drum or sealing bar, wherein the extrusion has at least two stages, such as at least two of pre-extrusion heating (also referred to as a pre-extrusion stage or pre-heating stage), controlled extrusion, and extrusion. A multi-stage extruder as used herein refers to an extrusion station that provides multi-stage extrusion (which may be thermal or ultrasonic). Multi-stage extrusion as used herein refers to performing multi-stage extrusion.

The bag machine preferably includes a controller having modules that control each stage of insert extrusion. The preferred embodiment provides that the controller includes a pre-press heating module that causes the drum to move in a pre-press heating phase, a controlled press module that causes the drum to move in a controlled press phase, and a press setting module that causes the drum to move in a press setting phase.

Controller, as used herein, refers to circuitry and software that controls the operation of one or more of the bag machine, the bag machine section, or portions of the bag machine section, and may include a built-in controller, such as a controller equipped with servo motors, and may be at a single location, or distributed over multiple locations. Control modules or modules as used herein refer to software and circuitry that cooperate to perform one or more defined functions, and control hardware and software may be part of multiple modules.

As used herein, a pre-extrusion module refers to a control module that causes a multi-stage sealer to include a pre-extrusion motion profile that is a motion profile that causes pre-extrusion to heat an insert prior to applying significant extrusion pressure to the insert. The pre-extrusion motion profile begins to heat the surface and provides a more uniform temperature profile to reduce intermolecular strain and seal shear stress. Pre-extrusion heating as used herein refers to heating the material to be extruded prior to applying the extrusion pressure.

Controlled extrusion module as used herein refers to a control module that causes a multi-stage sealer to include a controlled extrusion motion profile, which is a motion profile that results in controlled extrusion rates and pressures. Controlled extrusion as used herein refers to extruding an insert at a controlled extrusion rate and pressure.

As used herein, a compression set module refers to a control module that causes a multi-stage sealer to include a compression set motion profile, which is a motion profile that causes heating, wherein molecules relax and additional pressure does not exceed that generated by the compression motion. The extrusion set motion profile allows for relaxation of the transferred molecules and/or reduces intermolecular strain, which helps the extruded material retain its new shape and reduces the likelihood that the material will spring back creating seal shear stress. Compression set or set compression as used herein refers to heating the insert to obtain molecular relaxation without additional compression pressure to allow the transferred molecules to relax and/or reduce intermolecular strain.

The preferred embodiments will be described with respect to zipper inserts and zipper tapes. Alternative embodiments provide any type of insert, including hook and loop closures, press-to-close closures, tear tapes, vents, plugs, valves, spouts, strips, and the like. As used herein, an insert refers to a feature such as a closure (zipper, hook and loop, push-to-close, etc.), tear strip, vent, plug, valve, spout, strip, etc., that includes a material that is different from or has a different thickness than the material comprising the pouch or base. Insert tape as used herein refers to a taped insert. Tear tape as used herein refers to an insert tape used to create a tear tape that is part of a bag. Vent strip as used herein refers to an insert strip used to create a vent as part of a bag. The zipper strips as used herein refer to the strips of an insert used to create a zipper as part of a bag.

The preferred embodiment provides that the film or substrate follows a film path including (in this order) an unwind or feed section followed by a forming or folding section followed by a machine direction bottom seal and zipper flange seal section wherein the zipper is fed to provide a zipper strip followed by a zipper extrusion section followed by a side seal section followed by other processes such as cutting, perforating, etc. Side seals are seals that extend generally vertically along the sides of the bag when the bag is upright. The flange of the zipper is sealed to the bag and the zipper is sealed to the bag across the portion that will be horizontal and near the top when the bag is erected and in use (erected). An alternative embodiment is a zipper (or other insert) in a different position. Using the stages described herein, the zipper is crushed with the zipper in the side seal areas. Typically, between one and five cross seals are used to form the sides of the bag. Each action other than zipper squeezing may be consistent with the prior art.

Zipper crushing involves reducing the motion/heating profile of the rollers to provide zipper crushing to a first position where the zipper is contacted with a light non-crushing pressure, thus preheating the zipper (the pre-crushing stage). The drum is then lowered to the pressed or nip position (controlled nip phase) and the drum stays in the nip position (nip setting phase). The particular distribution may vary depending on the desired application.

One embodiment provides the profile shown in fig. 5, which includes an initial (non-contact) position of 0.165 inches, and the sealer is quickly lowered from the initial position by 0.125 inches to 0.04 inches (within 90 ms), where it contacts the zipper. The distances described herein vary with material type and thickness and are exemplary only. During the warm-up phase, this position is maintained for 30 ms. Then, the sealer is lowered 0.02 inches in the next 80ms while the zipper is being squeezed. Next, when setting the squeeze (squeeze setting phase), the sealer is kept at the same distance for 40 ms. The sealer is then snapped back to the starting position.

Alternative profiles include holding the initial position for between 0.01 seconds and 0.0765 seconds depending on the time required to compress the insert. The roller may stop between 0.001 inch (for no zipper) and 0.012 inch (for the spout) depending on the thickness of the insert. The length of time the position is held varies depending on the material. The time should be long enough to soften the material so that it does not break during the extrusion stage. Thicker materials require more time. The sealer is lowered by an amount depending on the material thickness and type during the controlled extrusion stage. In squeezing the zipper, for the next 80ms, next, when the squeezing is set (squeezing set stage), the sealer is kept at the same distance for 40 ms. The sealer is then snapped back to the starting position.

Another embodiment provides a motion profile that includes rapidly lowering the sealer 0.2 inches from an initial position so that it contacts the zipper. Then, while the zipper is preheating (in the preheating phase), the seal is lowered by 0.05 inches in the next 25 ms. Alternatives include lowering the sealer by 0.005 inches, or not lowering it at this stage or at this segment at all. The sealer is then lowered another 0.25 inch for the next 50ms, which squeezes the zipper (in the squeeze phase). An alternative provides lowering the sealer by 0.05 inches in this stage. The sealer then stays at the squeeze height for 25ms (at the squeeze setup stage) and then snaps back to the starting position.

The multi-stage extrusion improves the side seal bond strength by reducing intermolecular strain and seal shear. During the pre-extrusion heating stage, the insert material is heated under no pressure and the surface begins to heat. In addition, this "pre-extrusion heating" provides a more uniform temperature distribution, which reduces intermolecular strain and seal shear stress.

During the controlled extrusion phase, the seal strength can be optimized by balancing heat transfer and molten material flow/transfer, as well as by controlling the extrusion rate. Balancing heat and mass transfer reduces both molecular strain and shear stress on the seal area.

During the extrusion set-up phase, the transferred molecules relax, reducing the intermolecular strain. The result is that the extruded material is more likely to retain its new shape. Without this relaxation stage, the material may spring back to create stress on the seal.

The multi-stage extrusion provides more consistent temperature and flow, resulting in lower shear stress and stronger seals that are less likely to crack than prior art single stage extrusion. In addition, the extrusion set-up phase allows the crystalline segments of the polymer chains to unfold and relax to their new positions. This is in contrast to prior art single stage extrusion, which provides a compressive force that increases intermolecular strain. When the compressive force is released from the compression set-up stage of the present disclosure, the strain stress is reduced and the crystallized section will relax and spring back to the maximum compression position.

The preferred embodiment uses a zipper/insert extrusion station with servo-actuated linear screws. The servo motor provides the desired motion control and the screw converts the servo motion to the desired linear motion in order to move the roller at a precisely controlled rate and over a precisely controlled distance to provide three-stage extrusion. The servo motor can easily produce the desired three stages during the extrusion cycle, allowing the material to heat, seal, and flow while reducing shear and strain. Various embodiments use a linearly actuated screw servo motor with or without feedback control.

The preferred motion control provides the desired side seal bond strength and a less ruptured seal. Since the servo motor and the head position are directly coupled, servo motor error can be minimized and feedback control is possible. The error is minimized by using gearing and the error is consistent across the travel distance. With feedback control, there is no excessive pressure and little or no clearance. As the material heats up, the head displaces and the material flow is minimized, reducing shear stresses.

The temperature profile through the extruded insert material is not uniform during the first two phases of the extrusion motion profile. The temperature of some portion of the insert material closest to the heated extrusion die may be 40% to 50% higher than the melting temperature of the insert material at any given time during the first two stages and part of the motion profile into the third stage. The polymer at the sealing surface is heated to near the melting temperature and the amorphous chains can start to entangle during the preheating stage. The temperature variation at the sealing surface is reduced compared to that produced by prior art continuous pressure systems. The consistent temperature of the insert material results in a seal with minimal shear and strain.

The preferred embodiments provide shorter heating times to allow the material temperature and viscosity to become more consistent and at similar rates. As a result, the material flows at lower temperatures and requires less heat to overcome shear and strain. Fig. 6 shows insert 102 flow indicated by

arrows

602 and 604.

Entanglement of the amorphous chains may or may not occur upon extrusion of the insert. As the temperature is more consistent, the material flow will be similar and the seal shear stress will be reduced, which results in less entanglement. Control of the head allows the seal strength and cycle time to be optimized by balancing the pre-extrusion heating time, the heater rod temperature, and the extrusion rate. These settings will vary based on the material's heat capacity, thermal conductivity, viscosity, and volume of material displacement.

The press set-up phase begins when the drum or head stops at the target thickness. In the absence of extrusion force, flow is stopped and shear stress is eliminated; and intermolecular strain stress dissipates. The molecules can relax, allowing crystalline chain nesting, amorphous chain entanglement, and sealing to occur. Figure 7 shows three entangled polymer chains. As the chains entangle, the extruded material is more likely to retain its new shape and material spring back can be minimized along with the shear stress it generates. When the head stops at the desired position and thickness, process consistency exists and intermolecular strain is minimized along with spring back and seal shear.

During sealing, the individual polymer chains remain attached to each other from intermolecular mechanical entanglement, with no chemical reaction or bonding between the molecules. In thermoplastic substrates, the injection molding process creates entanglement due to time, temperature, and pressure. The degree of entanglement is governed by, among other things, the temperature profile, barrel length, screw geometry, and screw RPM. Sealing the thermoplastic is accomplished by applying pressure and heat over time to allow polymer chain entanglement. The pressure ensures a good contact between the conductive energy transfer and the sealing surface, which allows chain entanglement. Temperature is a measure of molecular energy and vibration; the vibration allows the polymer chains at the sealing surface to move, expand and entangle with each other. Time is critical to generating vibration and allows entanglement of the chains. The preferred embodiments consistently result in a high quality seal by providing a squeezing phase that allows for the desired entanglement.

The particular multi-stage profile selected for a particular application should be such that the extrusion results in a good temperature profile (more nearly uniform if possible) with a uniform flow of material. Figure 8 shows the polyethylene temperature for various residence times and distances from the sealing head. Zero inches is where the head contacts the polyethylene zipper, and the graph shows the temperature for various depths in the zipper.

An alternative embodiment uses a servo motor with an eccentric linkage to move the roller or head to provide three-stage extrusion. In the case of the servo motor and eccentric linkage embodiments, the extrusion may be delayed and the rate of extrusion may be controlled. Fig. 3 shows the travel and eccentric motion of the link mechanism for this embodiment. Full shrinkage corresponds to 100% in fig. 3. The squeeze sealer will open from about 3 to 5 up to 100% and back to 3 to 5.

The pressure is determined by the material thickness and the stop position of the drum or sealing head. The pressure increases non-linearly as the eccentric rotates and is typically not monitored or controlled. The desired pressure is provided by stopping at the correct position, and the stop position depends on the rotation of the eccentric via the servo motor. Control of the head or roller position is generally optimal when the eccentric is 175 to 179.5 degrees from top dead center. Fig. 4 shows the eccentric movement in the pressing area for the eccentric linkage. Full shrinkage corresponds to 100% in fig. 4. The pinch seal will open from about 3 ° to 5 ° all the way to 100%, and back to 3 ° to 5 °.

The anvil is preferably provided with a soft elastomeric rubber backing (40 to 60 durometer) to maintain consistent contact across the length of the sealing area and prevent damage from over travel of the extrusion die. When the head (and hence the servo) is in the correct position, heating will be as desired without excessive pressure to provide a consistently strong seal. In this alternative, there is pre-extrusion heating and the extrusion rate can be controlled, but there is no pressure feedback control as precise as the servo motor torque.

A bag machine according to the above description is shown in fig. 9. The bag machine includes a feeding section 902 that provides a film of material or substrate to a forming or folding section 904. The film follows a film path from the forming or folding section 904 to the machine direction bottom seal and zipper flange seal section 906. The film then follows a path to zipper extrusion 908, which operates as described above. Section 908 is a multi-stage insert extrusion station. A zipper feed section 910 (which is part of the feed section 902) provides zipper tape to the folded film. The side seal section 912 is downstream of the zipper crush section 908 and forms the side seal of the bag.

Other processes such as severing, puncturing, etc., are performed by segment 914 (and/or additional segments as needed). Additional stations may be included before or after the multi-stage insertion extrusion station 908. In one embodiment, segment 914 is an output segment. A film of material as used herein includes material fed to a bag machine that is used to form bags and includes laminate layers, monolayer films, and multilayer films. As used herein, a feed section refers to a bag-making machine section that feeds a film of material and/or an insert to a processing section that acts on the film to form bags. A sealed section as used herein refers to a section of a machine that applies at least some of the seals used to form the bag.

The multi-stage insert extrusion station 908 includes a multi-stage roller or sealing head 1100 (shown in fig. 11) as described above, which preferably provides a three-stage extrusion. Thus, station 908 is a multi-stage sealer. The controller 907 controls each segment of the machine 900. A multi-stage drum (or multi-stage sealing head) as used herein refers to a drum or sealing head that forms a seal having a motion profile that includes a plurality of slopes after contact of the sealed materials, and/or a plurality of dwell distances after contact of the sealed materials. A multi-stage sealer, as used herein, refers to a sealer that forms a seal having a motion profile that includes a plurality of slopes after material contact of the seal, and/or a plurality of dwell distances after material contact of the seal.

Fig. 10 shows a block diagram of a portion of a controller 907, which forms a multi-stage module that controls the movement of the rollers in station 908. The multi-stage module includes a pre-heat or pre-press module 1002. After the preheat module 1002 is used to control the rollers or sealing heads to provide the preheat phase, the controlled press module 1004 is used to control the rollers to provide the controlled press phase. After the controlled press module 1004 is used to control the rollers to provide a controlled press, a press setup module 1006 is used to control the rollers to provide a press setup phase. The distance module 1008 controls the rollers to move to a desired distance by providing a desired distance and/or feedback to other modules. The feedback is shown by arrow 1010. A distance module as used herein refers to a control module that causes the sealer to move a desired distance at a desired speed or speeds. A multi-stage module as used herein refers to a control module that controls the movement of the sealer and/or drum such that the drum is a multi-stage drum and/or sealer. Pre-extruding or pre-heating the insert as used herein refers to heating the insert prior to applying a greater extrusion pressure to the insert to provide a more consistent temperature profile to reduce intermolecular strain and seal shear stress.

One alternative provides for the use of a multi-stage station to apply the seal rather than providing an insert. The multi-stage station can produce a high quality and consistent seal with or without an insert. Another alternative provides a capsule making machine having at least some of the seals formed using a multi-stage sealer 1204, as shown in FIG. 12, having at least an upstream feed section 1202, a downstream output section 1206, and a controller 1208.

Another alternative provides for the use of ultrasonic energy to extrude the insert in a multi-stage station. The rollers (or other devices such as heads) may apply ultrasonic energy in multiple stages to provide pre-extrusion, controlled extrusion, and extrusion setup stages.

Many modifications may be made to the disclosure which still fall within its intended scope. It is therefore apparent that there has been provided a method and apparatus for making bags with multi-stage insert extrusion that fully satisfies the aims and advantages set forth above. While the invention has been described using specific embodiments thereof, it will be apparent that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the spirit and broad scope of the appended claims.

Claims

1. A bag machine having an insert pressing station, wherein the insert pressing station includes a multi-stage press configured to receive an insert and a substrate using at least two of a pre-press heating stage in which the insert is heated prior to application of pressing pressure, a controlled pressing stage in which the insert is pressed using a controlled pressing rate and pressure, and a pressing stage in which the insert is heated to obtain molecular relaxation without additional pressing pressure to allow transferred molecular relaxation and/or reduce intermolecular strain.

2. The bag machine of claim 1, wherein the insert press station includes a multi-stage sealing head and a controller connected to the multi-stage sealing head, and wherein the controller includes at least two of a pre-press heating module, a controlled press module, and a press setup module, wherein the at least two of the pre-press heating module, the controlled press module, and the press setup module operate continuously without returning to a home position between their operations.

3. The bag machine of claim 2, wherein the insert pressing station includes a servo motor operatively connected to move the multi-stage sealing head and is further connected to be responsive to the controller, and wherein the insert pressing station further includes at least one of an eccentric linkage and a linear actuation screw connected to the multi-stage sealing head and to the servo motor to translate movement of the servo motor into movement of the multi-stage sealing head.

4. The bag machine of claim 1, wherein the insert is one of a zipper strip, a tear strip and vent strip, a press-to-close zipper strip, a hook and loop strip, a tear strip, and a plug and valve strip.

5. The bag machine of claim 1, wherein the multi-stage extruder includes a heat source and does not include an ultrasonic source, and wherein the bag machine includes a second sealing station that forms a seal pattern to form a bag.

6. The bag machine of claim 1, further comprising a second insert pressing station that receives the base and insert.

7. The bag machine of claim 3, wherein at least one of the eccentric linkage and linear actuator screw is an eccentric linkage, and the eccentric linkage acts between 175 degrees and 180 degrees from top dead center.

8. The bag machine of claim 1, further comprising a controller including a distance module connected to the multi-stage extruder.

9. A bag machine having an insert press station, wherein the insert press station includes a controller including at least two of a pre-press heating module, a controlled press module, and a press setup module, wherein the at least two of the pre-press heating module, the controlled press module, and the press setup module operate in series.

10. The bag machine of claim 9, wherein the insert pressing station is a zipper pressing station.

11. The bag machine of claim 10, wherein the insert pressing station includes a heat source and does not include an ultrasonic source.

12. The bag machine of claim 11, further comprising an insert press station that receives the base and the insert.

13. A method of making a bag comprising:

feeding the substrate to an insert extrusion station;

feeding an insert to the insert pressing station;

multi-stage extruding the insert and substrate; and

a seal is formed to create a pouch.

14. The method of claim 13, wherein the multi-stage extrusion comprises at least two of a pre-extrusion heating, a controlled extrusion, and an extrusion setting, wherein the at least two of the pre-extrusion heating, the controlled extrusion, and the extrusion setting are sequential.

15. The method of claim 14, wherein the insert is a zipper.

16. The method of claim 14, wherein the multi-stage extrusion comprises providing heat and does not comprise providing ultrasonic energy.

17. The method of claim 14, further comprising controlling a second insert pressing station that receives the insert and the substrate.

18. A method of making a bag comprising:

feeding the substrate to an insert extrusion station;

feeding an insert to the insert pressing station; and

controlling an insert extrusion station to provide at least two of a pre-extrusion heating, a controlled extrusion, and an extrusion setting of the insert and substrate, wherein the at least two of the pre-extrusion heating, the controlled extrusion, and the extrusion setting are continuous.

19. The method of claim 18, wherein providing an insert comprises providing a zipper.

20. The method of claim 18, wherein providing at least two of the pre-extrusion heating, the controlled extrusion, and the extrusion settings comprises providing heat and does not comprise providing ultrasonic energy.

21. The method of claim 18, further comprising controlling a second insert pressing station that receives the insert and the substrate.

22. A bag machine for making bags, comprising:

means for feeding the substrate to an insert pressing station;

means for feeding an insert to the insert pressing station;

means for multi-stage extruding the insert and substrate; and

means for forming a seal to create a bag, wherein the means for forming a seal receives the insert and the base.

23. The bag machine of claim 22, wherein the insert is a zipper.

24. The bag machine of claim 23, wherein the means for multi-stage pressing includes a heat source and does not include an ultrasonic energy source.

25. The bag machine of claim 24, further comprising a second insert pressing station that receives the insert and the base.

26. A bag making machine comprising:

means for feeding the substrate to an insert pressing station;

means for feeding an insert to the insert pressing station;

means for controlling an insert extrusion station to provide at least two of a pre-extrusion heating, a controlled extrusion, and an extrusion setting of the insert and substrate, wherein the at least two of the pre-extrusion heating, the controlled extrusion, and the extrusion setting are continuous.

27. The bag machine of claim 26, wherein the insert is a zipper.

28. The bag machine of claim 27, wherein the means for controlling an insert press station controls the insert press station to provide the pre-press heating, the controlled press, and the press settings, including providing heat, and not including providing ultrasonic energy.

29. The bag machine of claim 28, further comprising controlling a second insert pressing station.

30. A machine for making at least one of pouches and pouches having a film path including an upstream direction and a downstream direction, the machine comprising:

a feed section located on the film path and arranged to receive a film of material;

a sealing station located on the film path downstream of the feed section and having a multi-stage sealer; and

an output section located on the film path downstream of the sealing station.