Patent Description:
The strand coating system includes a nozzle for discharging the hot melt adhesive onto the one or more elasticated strands of material. The nozzle assembly may be a contact applicator assembly for applying the adhesive directly onto the strands or a non-contact applicator assembly, where the adhesive is discharged over an air gap onto the strands. The nozzle includes an orifice through which the hot melt adhesive may be discharged. In one strand coating system, the flow of hot melt adhesive through the nozzle may be metered to control a coating weight of the hot melt adhesive on the strand of material.

In some applications, it may be desirable to vary a coating weight of the hot melt adhesive along a length of the strand of material. Such varied coating weights may be realized in a number of different ways. For example, the strand of material may be passed through a nozzle multiple times. For instance, a first pass through a nozzle may allow for a base coating on the strand, and a second or subsequent pass through the nozzle may allow for intermittent application of the hot melt adhesive to selectively add weight to the strand. However, such a process is time consuming and labor intensive.

Another system for varying the coating weight of a hot melt adhesive applied to the strand of material involves using two spaced apart nozzles arranged along a direction of travel of the strand of material. A first nozzle may apply a base coating of hot melt adhesive to the strand and a second nozzle may be controlled to add weight to the strand. However, such a system requires additional equipment (e.g., multiple nozzles) and may occupy a large area in a manufacturing assembly due to the additional equipment.

Still another system for varying a coating weight of a hot melt adhesive on a strand of material is described in <CIT>. In a non-contact application, Adams et al. uses two separate nozzles, independently operated, to apply the hot melt adhesive material to an elasticated strand. For example, one nozzle applies a base layer of hot melt adhesive to a plurality of elasticated strands, and a second, distinct nozzle is operated to apply a second layer of hot melt adhesive to the strands, thereby selectively adding weight to the strands. However, as described above, the use of multiple nozzles increases equipment and associated costs, maintenance, space and the like. In addition, by using a single nozzle and single orifice to apply the hot melt adhesive to multiple strands, overspray (discharged hot melt not received on a strand) may become an issue, which can lead to an inefficient coating process and increased material costs.

In a contact application, Adams et al. provides a nozzle having multiple discharge orifices arranged in a direction along a length of the elasticated strand. Flow of hot melt adhesive may be controlled through each discharge orifice as either on or off to control a coating weight of hot melt adhesive applied on the elasticated strand. That is, a coating weight of the hot melt adhesive may be controlled by allowing or preventing hot melt adhesive to be discharged from different discharge orifices. However, manufacture of such a nozzle requires significant machining, which may be time consuming and costly. <CIT> discloses a method and apparatus for accurately dispensing liquids and solids. <CIT> discloses a battery electrode plate manufacturing device and manufacturing method. <CIT> discloses a fluid application device having a modular nozzle assembly for applying fluid to an article. <CIT> discloses a fluid application device having a nozzle with individually metered orifice or orifices.

Accordingly, it is desirable to provide a fluid application device in a strand coating system capable of discharging varying volumes of a material from a single orifice of a nozzle.

According to one aspect, a fluid application device includes a service an applicator head, a first fluid passageway extending in the applicator head, a second fluid passageway extending in the applicator head, and a plurality of metering devices connected to the applicator head. A first metering device of the plurality of metering devices is configured to meter a fluid to the first fluid passageway and a second metering device of the plurality of metering devices is configured to meter the fluid to the second fluid passageway. The fluid application device further includes a plurality of valve modules connected to the applicator head,
each valve module actuatable between an open condition and a closed condition to control flow of the fluid, and a nozzle connected to the applicator head, the nozzle having a plurality of discharge orifices. At least one orifice of the plurality of discharge orifices is positioned downstream from the first passageway and the second passageway and is configured to receive the material from each of the first and second fluid passageways. Additionally, the nozzle includes an internal conduit connected between the first and second fluid passageways and the plurality of discharge orifices for receiving the fluid from the first and second fluid passageways, and the internal conduit includes a splitting section to split the fluid for flow to the plurality of discharge orifices, and wherein the plurality of discharge orifices are disposed along a common line.

According to another aspect, a method for varying a volume of material discharged from a nozzle orifice of a fluid application device includes metering a first volume of material to the nozzle orifice via a first fluid passageway, metering a second volume of material to the nozzle orifice via a second fluid passageway, and controlling flow of the second volume of material to the nozzle orifice with a valve module in the second fluid passageway. Controlling flow of the second volume of material includes opening the valve module to provide the second material to the nozzle orifice, and closing the valve module to prevent flow of the second material to the nozzle orifice.

<FIG> is a perspective view of a fluid application device <NUM> according to an embodiment described herein. <FIG> is a perspective view of a fluid application device <NUM> according to another embodiment. Referring to <FIG> and <FIG>, the fluid application device <NUM> includes, generally, an applicator head <NUM>, a plurality of metering devices <NUM>, one or more valve modules <NUM> and a nozzle <NUM>. The applicator head <NUM> may include, for example, a service block <NUM> and an adapter <NUM> secured to one another. In one example, the service block <NUM> and adapter may be secured directly to one another in an abutting relationship. In one embodiment, the nozzle <NUM> is a contact applicator configured to apply a material onto individual strands <NUM>. In another embodiment, the nozzle <NUM> may be a non-contact applicator or a slot die applicator. In a contact applicator or nozzle, material is applied directly onto strands or a substrate. That is, the strand or substrate is in contact or near contact with the material or an orifice from which the material is discharged, as the material is discharged. In a non-contact applicator or nozzle, the material is discharged over an air gap onto the strand or substrate. First and second fluid
passageways <NUM>, <NUM> (see <FIG> and <FIG>) are formed in the applicator head <NUM>, for example, in the the service block <NUM> and adapter <NUM>, to allow flow of the material through the service block <NUM> and the adapter <NUM> to the nozzle <NUM>.

According to the invention, the plurality of metering devices <NUM> are one or more pumps. In one embodiment, the pumps may be gear pumps. The gear pumps may be provided in the form of a plurality of stacked plates having gears driven by a common motor. In some embodiments, the gear pumps may be those shown and disclosed in <CIT>, commonly owned with the present application or those shown and disclosed in <CIT>or <CIT>, both of which are commonly owned with the present application. The metering devices <NUM> may be mounted or removably mounted directly to the applicator head <NUM>, for example, to the service block <NUM>. In another embodiment, the metering devices <NUM> may be remotely positioned from the applicator head <NUM>.

The metering devices <NUM> are configured to receive a material, such as a hot melt adhesive, from a supply source (not shown). Referring to <FIG> and <FIG>, in one embodiment, the metering devices <NUM> include a first metering device <NUM> configured to meter the material to the first fluid supply passageway <NUM> and a second metering device <NUM> configured to meter the material to the second fluid supply passageway <NUM>. That is, the first metering device <NUM> is configured to meter a first portion or volume of the material and the second metering device <NUM> is configured to meter a second portion or volume of the material. In one embodiment, the applicator head <NUM> may further include a manifold <NUM> disposed between the metering devices <NUM> and the service block <NUM>, and the metering devices <NUM> may be removably mounted directly to the manifold <NUM>. The first and second fluid passageways <NUM>, <NUM> extend through the manifold <NUM>.

The adapter <NUM> is connected to the service block <NUM> using known, suitable fasteners, such as threaded fasteners and the like, and is fluidically connected to the service block <NUM> to receive the material from the first and second fluid passageways <NUM>, <NUM>. Referring to <FIG>, in one embodiment, the first and second fluid passageways <NUM>, <NUM> extend through the adapter <NUM> to respective first and second outlets <NUM>, <NUM>.

Referring to <FIG>, in another embodiment, the first and second fluid passageways <NUM>, <NUM> may intersect to form a third fluid passageway <NUM> in the applicator head <NUM>, for example in the adapter <NUM> or service block <NUM>. The third fluid passageway <NUM> extends to a single material outlet <NUM>.

The nozzle <NUM> is secured to the applicator head <NUM>, for example, to the adapter <NUM>, using known suitable fasteners, such as a threaded fastener and the like. The nozzle <NUM> is fluidically connected to the adapter <NUM> and is configured to receive the material from the adapter <NUM>. According to the invention, nozzle <NUM> includes a plurality of discharge orifices <NUM> to discharge the material. In one embodiment, the nozzle <NUM> includes first and second inlets <NUM>, <NUM> configured to receive the material from the first and second outlets <NUM>, <NUM>, respectively, of the adapter <NUM>. In another embodiment, the nozzle <NUM> include a single material inlet <NUM> configured to receive the material from the single material outlet <NUM> corresponding to the third fluid passageway <NUM> of the adapter <NUM>. The one or more discharge orifices <NUM> are positioned downstream from the first fluid passageway <NUM> and the second fluid passageway <NUM> and are configured to selectively receive and discharge the material from both the first and second fluid passageways <NUM>, <NUM>.

As shown in <FIG>, the nozzle <NUM> includes one or more internal conduits <NUM> interconnected between the first and second fluid passageways <NUM>, <NUM> and the one or more discharge orifices <NUM>. The one or more internal conduits <NUM> may intersect such that material received in the nozzle <NUM> from the first and second fluid passageways <NUM>, <NUM> may be combined into a single flow. The one or more internal conduits also include a splitting section down stream from the intersection where the flow of material is split for discharge from a plurality of orifices <NUM>. In another embodiment, as shown in <FIG>, the material may be received in the nozzle <NUM> from the third fluid passageway <NUM>, and split among a plurality of discharge orifices <NUM> by the internal conduits <NUM>.

In one embodiment, the nozzle <NUM> may be a laminated plate nozzle comprising a plurality of stacked plates secured together with suitable fasteners, such as threaded fasteners. Examples of such laminated nozzle plates are shown and described in <CIT>, commonly owned with the present application. According to the invention, the plurality of discharge orifices <NUM> are disposed along a common line. For example, the discharge orifices <NUM> may all be disposed on a single plate of the stacked plates.

As shown in <FIG>, the one or more valve modules <NUM> may include a first valve module <NUM> and a second valve module <NUM>. The first valve module <NUM> includes a first valve configured to actuate between an open condition and a closed condition in the first fluid passageway <NUM>. In the open condition, material flow is permitted through the first fluid passageway <NUM> and in the closed condition, material flow is limited or prevented. Similarly, the second valve module <NUM> includes a second valve configured to actuate between an open condition and a closed condition in the second fluid passageway <NUM>. In the open condition, material flow is permitted through the second fluid passageway <NUM> and in the closed condition, material flow is limited or prevented. The one or more valve modules <NUM> may be mounted on the adapter <NUM> or the service block <NUM>. The first and second valves may be solenoid valves but are not limited thereto.

Referring to <FIG>, in one embodiment, the first and the second valve modules <NUM>, <NUM> may be mounted on the applicator head <NUM> at a non-parallel angle relative to one another. In such a configuration, the applicator head, for example, at the adapter <NUM>, may include angled faces on which the valve modules <NUM>, <NUM> are mounted. Alternatively, the valve modules <NUM>, <NUM> may include angled mounting faces. Corresponding valves of the valve modules <NUM>, <NUM> project along lines which intersect. Accordingly, when projected to a closed position, the valves of the valve modules <NUM>, <NUM> move toward one another and are laterally closer to one another in the closed condition than in the open condition. Accordingly, the first and second fluid passageways <NUM>, <NUM> may be positioned closer to one another. Because of a shorter distance between the first and second fluid passageways <NUM>, <NUM>, a nozzle <NUM> having a smaller width may be used.

The fluid application device may further include a controller <NUM> operatively connected to the valve modules <NUM>, <NUM>. The controller <NUM> is configured control actuation of the valves between open and closed condition. For example, the controller <NUM> may actuate the valves at predetermined intervals or in response to operator input. In addition, the controller <NUM> may be operatively connected to the metering device <NUM> to control flow rate through the first and second metering devices <NUM>, <NUM>, for example. In one embodiment, the controller <NUM> may be connected to a drive motor of the metering device <NUM> to control an output of the drive motor.

The fluid application device may include additional components such as, but not limited to, a heater, a filter, power inputs, and strand positioning elements for positioning strands of material relative to the nozzle <NUM>. Further, as shown in <FIG>, varying numbers of strands <NUM> may be fed by the nozzle <NUM>. For example, as shown in <FIG>, a single strand <NUM> is fed by the nozzle <NUM>. In <FIG>, three strands <NUM> are fed by the nozzle <NUM>, and in <FIG> two strands <NUM> are fed by nozzle <NUM>. The present disclosure is not limited to such numbers of strands <NUM>, however. In one embodiment, each discharge orifice <NUM> discharges the material onto a respective strand <NUM>.

In the embodiments above, the first metering device <NUM> meters a first volume of material to the first fluid passageway <NUM>. The first volume of material subsequently flows into the third fluid passageway <NUM> or the internal conduits <NUM> of the nozzle <NUM>. The first volume of fluid then flows to one or more of the discharge orifices <NUM> to be discharged and applied to one or more respective strands <NUM>. The second metering device <NUM> meters a second volume of material to the second fluid passageway <NUM>. The second volume of material subsequently flows into the third fluid passageway <NUM> or the internal conduits <NUM> of the nozzle <NUM>. The second volume of fluid then flows to one or more of the discharge orifices <NUM> to be discharged and applied to one or more respective strands <NUM>, such that the first volume of material and second volume of material are discharged together from the same orifice <NUM> or orifices <NUM>. The second volume of material may be the same as or different from the first volume of material.

Discharge of the first and second volumes of material may be controlled by the valve module <NUM>. In one embodiment, the valve module <NUM> includes the first valve module <NUM> and the second valve module <NUM>, which are selectively disposed in the first and second fluid passageways <NUM>, <NUM>, respectively. In an open condition, the valve modules <NUM>, <NUM> allow for passage of the first and second volumes of material, respectively, and in a closed condition, the first and second valve modules <NUM>, <NUM> prevent flow of the first and second volumes of material, respectively.

In use, the nozzle <NUM>, and in particular, an orifice <NUM> of the nozzle <NUM>, may discharge the first volume of material to apply a first coating weight of the material on the one or more strands <NUM>. The second volume of material may be discharged from the same orifice <NUM>, together with the first volume of material, to provide an add-on or increased coating weight of the material to the one or more strands <NUM>. A controller <NUM> may be operable connected to the valve modules <NUM>, <NUM> to control opening and closing of the valve modules <NUM>, <NUM>. Accordingly, as a strand <NUM> is fed by the nozzle <NUM> of the fluid application device <NUM>, a coating weight of the material applied on the strand may be varied by controlling the first and second valve modules <NUM>, <NUM>.

The fluid application device <NUM> is operable in a number of different states based on the condition of the first and second valve modules <NUM>, <NUM>. In a first state, the first valve module <NUM> is open and the second valve module <NUM> is closed. Accordingly, a first volume of material may be discharged from the orifices(s) <NUM> to apply a first coating weight on the strand(s). In a second operating state, the first valve module <NUM> and the second valve module <NUM> are open. Accordingly, a first volume and a second volume of the material are simultaneously discharged from the orifice(s) to apply a second coating weight on the strand(s). In a third operating state, both the first valve module <NUM> and second valve module <NUM> are closed, such that no material, or substantially no material is discharged from orifice(s) or applied to the strand(s). In a fourth state, the first valve module <NUM> may be closed and the second valve module <NUM> may be opened, such that only the second volume of material is discharged from the orifice(s) to a apply a third coating weight on the strand(s). Referring to <FIG>, the strands <NUM> may include lengths having different coating weights. For example, a first coating weight is shown at C1, a second coating weight at C2, and an uncoated section at C3. The present disclosure is not limited to such coating weights or patterns, however.

<FIG> is a diagram showing a method S300 of varying a volume of material discharged from a nozzle orifice of a fluid application device. According to the embodiments described herein, the method includes metering a first volume of material to a first fluid passageway <NUM> at S3 <NUM>, metering a second volume of material to a second fluid passageway <NUM> at S320, and controlling flow of the second volume of material to the nozzle orifice <NUM> with a valve module <NUM> in the second fluid passageway at S330. Controlling flow of the second volume of material includes opening the valve module <NUM> to provide the second material to the nozzle orifice at S332, and closing the valve module <NUM> to prevent flow of the second material to the nozzle orifice <NUM> at S334. The nozzle orifice <NUM> includes a plurality of nozzle orifices <NUM>. The method may further include controlling flow of the first volume of material by opening or closing another valve module <NUM> to selectively allow or prevent flow of the first volume of material to the orifice <NUM>.

Claim 1:
A fluid application device (<NUM>) comprising:
an applicator head (<NUM>);
a first fluid passageway (<NUM>) extending in the applicator head (<NUM>);
a second fluid passageway (<NUM>) extending in the applicator head (<NUM>);
a plurality of pumps (<NUM>) connected to the applicator head (<NUM>), a first pump (<NUM>) of the plurality of pumps (<NUM>) configured to meter a fluid to the first fluid passageway (<NUM>) and a second pump (<NUM>) of the plurality of pumps (<NUM>) configured to meter the fluid to the second fluid passageway (<NUM>);
a plurality of valve modules (<NUM>) connected to the applicator head (<NUM>), each valve module actuatable between an open condition and a closed condition to control flow of the fluid in the first fluid passageway (<NUM>) and the second fluid passageway (<NUM>);
a nozzle (<NUM>) connected to the applicator head (<NUM>), the nozzle (<NUM>) having a plurality of discharge orifices (<NUM>), wherein at least one orifice of the plurality of discharge orifices (<NUM>) is positioned downstream from the first fluid passageway (<NUM>) and the second fluid passageway (<NUM>);
wherein the nozzle (<NUM>) includes an internal conduit (<NUM>) connected between the first and second fluid passageways and the plurality of discharge orifices (<NUM>) for receiving the fluid from the first and second fluid passageways, and
the internal conduit (<NUM>) includes a splitting section to split the fluid for flow to the plurality of discharge orifices (<NUM>), and wherein the plurality of discharge orifices (<NUM>) are disposed along a common line.