Nozzle and applicator system for fabric bonding

Nozzle assemblies and methods of bonding fabric by jetting an adhesive are disclosed. A method of bonding fabrics with an adhesive includes receiving the adhesive from an adhesive supply into a nozzle assembly. The nozzle assembly has a valve seat, a valve stem configured to slidably move towards and away from the valve seat, and a plurality of outlet channels. The method further includes jetting the adhesive from the plurality of outlet channels onto a first fabric and applying a second fabric to the first fabric to adhere the first and second fabrics to each other.

TECHNICAL FIELD

This disclosure generally relates to applicator systems for applying a material to a substrate and, more particularly to a nozzle assembly for use in an applicator system for applying a material to fabric.

BACKGROUND

In the garment manufacturing field, applicator systems are commonly used to apply a material, such as a polyurethane (PUR) glue, to a fabric or cloth for binding pieces of the fabric or cloth together. When bonding pieces of fabric together, an applicator system is required that has the ability to spray a small amount of a material with a high degree of accuracy and precision. For example, the width of the desired strip of material to be applied to a fabric can have requirements of less than 8 mm in width and less than 0.2 mm in height. In many currently existing applicator systems, material is sprayed with low levels of accuracy and precision, which can result in the spraying of excessive amounts of material.

Additionally, applicator systems are difficult to adjust to create the desired pattern of dispensed material. Often, not enough material is applied to the fabric to create a sufficient bond. If more material is desired, separate application processes are run, resulting in longer manufacturing times, increased machinery wear, and added costs.

Therefore, there is a need for an applicator system that can be adjusted to accurately jet material in the desired patterns and amounts without requiring excess application times.

SUMMARY

The foregoing needs are met by the various embodiments of applicator systems and nozzle assemblies disclosed. According to one embodiment, a method of bonding fabrics with an adhesive includes receiving the adhesive from an adhesive supply into a nozzle assembly. The nozzle assembly has a valve seat, a valve stem configured to slidably move towards and away from the valve seat, and a plurality of outlet channels. The method further includes jetting the adhesive from the plurality of outlet channels onto a first fabric and applying a second fabric to the first fabric to adhere the first and second fabrics to each other.

According to another embodiment, a nozzle assembly for jetting an adhesive to bond fabrics includes a body defining a chamber therein between an inlet and an outlet. The chamber is configured to receive the adhesive through the inlet and to allow the adhesive to exit through the outlet. The nozzle assembly further includes a valve seat disposed adjacent to the outlet, a valve stem configured to slidably move within the chamber towards and away from the valve seat and to contact the valve seat, and a plurality of outlet channels in fluid communication with the outlet of the chamber. Each of the plurality of outlet channels is configured to receive the adhesive from the chamber. The valve stem is configured to impact the valve seat such that a discrete volume of the adhesive is forcefully ejected from the plurality of outlet channels due to the momentum of the impact between the valve stem and the valve seat onto a fabric.

According to another embodiment, an applicator system for jetting an adhesive onto a fabric includes a material supply for storing the adhesive, a pump fluidly connected to the material supply, a valve for controlling operation of the pump, and a nozzle assembly configured to receive the adhesive from the pump and to jet the adhesive onto the fabric. The nozzle assembly includes a body defining a chamber therein between an inlet and an outlet, with the chamber being configured to receive the adhesive through the inlet and to allow the adhesive to exit through the outlet. The nozzle assembly further includes a valve seat disposed adjacent to the outlet, a valve stem configured to slidably move within the chamber towards and away from the valve seat and to contact the valve seat, and a plurality of outlet channels in fluid communication with the outlet of the chamber. Each of the plurality of outlet channels is configured to receive the adhesive from the chamber. The valve stem is configured to impact the valve seat such that a discrete volume of the adhesive is forcefully ejected from the plurality of outlet channels due to the momentum of the impact between the valve stem and the valve seat onto the fabric.

Aspects of the disclosure will now be described in detail with reference to the drawings, wherein like reference numbers refer to like elements throughout, unless specified otherwise.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Described herein is an applicator system10and a related nozzle assembly100for spraying a material onto a substrate. Certain terminology is used to describe the applicator system10in the following description for convenience only and is not limiting. The words “right,” “left,” “lower,” and “upper” designate directions in the drawings to which reference is made. The words “inner” and “outer” refer to directions toward and away from, respectively, the geometric center of the description to describe the applicator system10and related parts thereof. The words “forward” and “rearward” refer to directions in a longitudinal direction2and a direction opposite the longitudinal direction2along the applicator system10and related parts thereof. The terminology includes the above-listed words, derivatives thereof, and words of similar import.

Unless otherwise specified herein, the terms “horizontal,” “lateral,” and “vertical” are used to describe the orthogonal directional components of various components of the applicator system10, as designated by the longitudinal direction2, lateral direction4, and vertical direction6. It should be appreciated that while the longitudinal and lateral directions2and4are illustrated as extending along a horizontal plane, and the vertical direction6extends in a direction that is normal to the horizontal plane, the planes that encompass the various directions may differ during use.

Referring toFIGS.1-4, the applicator system10includes a material supply12for storing a supply of the material. The material can be received by material supply12in a prepackaged syringe (not shown), directly filled into a reservoir defined within the material supply12, or pumped to the material supply12from an external supply (not shown) spaced from the applicator system10. In some embodiments, the material may be a glue, such as polyurethane (PUR) glue, though other materials are contemplated. The material supply12can be configured to melt and/or maintain the material at an elevated temperature while it remains within the material supply12. In some embodiments, the material supply12can be designed to hold up to 300 cubic centimeters (cc) of material, though the material supply12can be larger or smaller as desired. The material supply12can include a heating element (not shown) to provide heat to the material within the material supply12, or, alternatively, to maintain a desired temperature within the material supply12. This prevents the material from cooling when it is being dispensed, thus preserving the desired material flow properties. In some embodiments, the applicator system10may include a second heating element (not shown) that is configured to maintain the material (e.g. adhesive) at a different temperature than the heating element described above.

The applicator system10also includes a pump16fluidly connected to the material supply12. The pump16can include a body31comprising a top component32aand a middle component32battached to and positioned below the top component32a. It will be understood that the pump16can alternatively define a monolithic body or have any other number of components.

The body31of the pump16defines a substantially hollow body, such that an upper chamber36and a lower chamber38are defined within the body31. A seal pack40is positioned within the body31and divides the interior of the body31into the upper and lower chambers36,38.

A nozzle100can be removably coupled to the body31and positioned, for example, below the middle component32b. The nozzle100can be selected from a plurality of nozzles100that are each configured to jet different patterns. In alternative embodiments, the nozzle100can be part of the monolithic body31. The lower chamber38may be disposed within the nozzle100. A valve seat104is disposed at the lower end of the lower chamber38and is defined by the nozzle100. A plurality of outlet channels108are disposed adjacent to the valve seat104and extend through the nozzle100. The plurality of outlet channels108are in fluid communication with the lower chamber38.

The pump16also includes a firing pin48positioned within the body31. The firing pin48defines an upper end48aand a valve stem48bthat extends from the upper end48aalong the vertical direction6. The upper end48ais positioned within the upper chamber36, while the valve stem48bextends from the upper end48athrough the upper chamber36, through the seal pack40, and into the lower chamber38.

In operation, the firing pin48is configured to reciprocate within the body31between a retracted and an extended position. This reciprocation can be caused by pressurized air that flows into the upper chamber36through first and second air paths52a,52b. Each of first and second air paths52a,52bcan receive pressurized air from a valve20, which is connected to the pump16through connector24. The valve20can be a pneumatic valve, an electronic valve, or any other type of valve as desired. The upper end48aof the firing pin48divides the upper chamber36into first and second portions36a,36b, where the first portion36acan receive pressurized air from the first air path52a, and the second portion36bcan receive pressurized air from the second air path52b. When pressurized air flows through the first air path52aand into the first portion36aof the upper chamber36, the firing pin48is driven downwards along the vertical direction6into an extended position. In contrast, when pressurized air flows through the second air path52band into the second portion36bof the upper chamber36, the firing pin48is driven upwards along the vertical direction6into a retracted position.

Continuing withFIGS.1-4, the pump16includes a circumferential chamber54defined between an outer surface of the nozzle100and an inner surface of the middle component32b. The circumferential chamber54is fluidly connected to the material supply12, such that the circumferential chamber54is configured to receive material from the material supply12and allow the material to flow through the circumferential chamber54to radial holes56defined within the nozzle100. The material can then flow through the radial holes56to the lower chamber38. In some embodiments, the radial holes56comprise four radial holes spaced equidistantly circumferentially around the nozzle100. However, it is contemplated that the radial holes56can comprise more or less holes, as well as holes having non-equidistant spacing.

When the firing pin48is in the retracted position, the valve stem48bis spaced from the valve seat104defined by the nozzle100. In this position, material flows through the circumferential chamber54, through the radial holes56, and into the lower chamber38. Then, when the firing pin48is transitioned into the extended position, the valve stem48bof the firing pin48moves rapidly downward along the vertical direction6through the lower chamber38towards the valve seat104. During this transition, the firing pin48causes an amount of the material within the lower chamber38to be discharged through the outlet channels108. When in the extended position, the lower end of the valve stem48bmay contact the valve seat104and thus create a fluid seal between the lower chamber38and each of the outlet channels108, or may be positioned slightly above the valve seat104.

When the firing pin48transitions from the retracted position to the extended position along the vertical direction6, the firing pin48travels a distance that can be referred to as the stroke length. The required stroke length can vary between dispensing operations, types of materials dispensed, wear of internal parts over time, etc. As a result, the stroke length can be adjusted using the limiting rod44, which extends through the top component32aof the body31and into the first portion36aof the upper chamber36. When the firing pin48is in the retracted position, the upper end48acan contact the lower end of the limiting rod44, such that the limiting rod44controls the how far upwards the firing pin48moves in the retracted position. The limiting rod44can threadedly engage the top component32a, such that rotation of the limiting rod44relative to the top component32amoves the limiting rod44further into or out of the upper chamber36, thus changing the maximum upward position of the firing pin48in the retracted position, and likewise the stroke length.

Referring toFIGS.4-7, the nozzle100may include three outlet channels108, although it will be understood that the nozzle100may include another suitable number of outlet channels108, for example, one, two, four, five, or six outlet channels. For example, illustrative embodiments depicted inFIGS.9and10show suitable nozzles100having one outlet channel108and two outlet channels108, respectively. Each of the outlet channels108may be disposed at an angle from the vertical direction6between 0° and 90°. In some embodiments, some or all of the outlet channels108may be parallel to one or more of the other outlet channels108and may be disposed along the vertical direction6. The specific angle of each of the outlet channels108can depend on the size and/or shape of the valve seat104, the size and/or shape of the valve stem48b, the material that is being dispensed, on the desired distance between the droplets dispensed from each of the outlet channels108, or on other manufacturing requirements and/or preferences.

When the firing pin48transitions from the retracted position to the extended position and then from the extended position back to the retracted position, this can be referred to as a stroke. With each stroke, the material within the lower chamber38of the nozzle100is moved through the outlet channels108. The firing pin48is configured to impact the valve seat104, such that a discrete volume of the material is forcefully ejected (i.e. jetted) from the nozzle towards the substrate200due to the momentum of the impact between the valve stem48bof the firing pin48and the valve seat104. Jetting is contrasted with extrusion or other types of material dispensing, where liquid material is dispensed as a continuous, elongate filament, generally referred to as a “bead” of adhesive. While drops can be formed by rapidly opening and closing a valve during extrusion of liquid material, or by using air to break up an extruded bead as it is dispensed, these processes are distinctly different from jetting processes, in which the discrete liquid mass is rapidly ejected directly from the dispenser at a high velocity when the firing pin48strikes the valve seat104. The liquid material (e.g. adhesive) is received into the lower chamber38at a low pressure and is jetted out of the lower chamber38at a higher pressure. The high pressure is developed as the valve stem48bis moved towards the valve seat104. When the valve stem48bimpacts the valve seat104, a portion of the liquid material (in the form of a droplet or a dot) can break away from the nozzle assembly100. So, in some embodiments, the jetted material can be separated from the nozzle assembly100before it contacts the substrate200.

By providing a plurality of outlet channels108, a single stroke can result in the dispensing of multiple droplets from the nozzle100onto a substrate200. It will be understood that the stroke length, the amount of material present in the lower chamber38, and the number and dimensions of the outlet channels108are all parameters that can be modified to achieve the desired dispensing.

In the exemplary embodiments ofFIGS.4-7, three outlet channels108are depicted in the nozzle100. With each stroke of the firing pin48, three separate droplets are jetted from the nozzle100onto the substrate200(seeFIG.8). This allows for simultaneous dispensing of more material, resulting in decreased manufacturing time and associated costs. The number and arrangement of the outlet channels108can be adjusted based on the desired usage, which adds versatility to each dispensing device and nozzle100.

The distance between adjacent droplets that are dispensed onto the substrate200can be controlled by the distance between the outlet channels108and the angle of each outlet channel108relative to the vertical direction6. Alternatively, or additionally, the distance between dispensed droplets can be altered by moving the nozzle100closer to or farther from the substrate200. In some embodiments, such as depicted inFIG.7, a first outlet channel108ais disposed along the vertical direction6, a second outlet channel108bis disposed at an angle between 0° and 90° from the vertical direction6in the negative horizontal direction4, and a third outlet channel108cis disposed at an angle between 0° and 90° from the vertical direction6in the positive horizontal direction4opposite the negative horizontal direction. In this depicted embodiment, the distance on the substrate200between each of the three droplets dispensed from the outlet channels108a,108b, and108cwill positively correlate with the distance of the nozzle100from the substrate200.

Specific arrangements of the outlet channels108on the nozzle100can also determine the dispensing pattern on the substrate200. If will be appreciated that the desired pattern will depend on the specific substrate, application use, material being dispensed, and on other manufacturing parameters, and that this specification is not limited to any specific dispensing patterns. The applicator system10may include a movement mechanism configured to move the applicator system10and/or the nozzle100in two, four, or six degrees of motion.

In some embodiments, the applicator system10can be used for bonding fabric materials. For example, the applicator system10may dispense a plurality of droplets of adhesive material, such as polyurethane (PUR) glue, onto a fabric substrate, which is then configured to receive and adhere to a different portion thereof or to a separate fabric material. By bonding multiple fabrics, a garment can be assembled with or without stitching.

While systems and methods have been described in connection with the various embodiments of the various figures, it will be appreciated by those skilled in the art that changes could be made to the embodiments without departing from the broad inventive concept thereof. It is understood, therefore, that this disclosure is not limited to the particular embodiments disclosed, and it is intended to cover modifications within the spirit and scope of the present disclosure as defined by the claims.