Systems and methods for controlling adhesive application - Patents.com

Abstract

A method of controlling a more consistent amount of material applied includes implementing a conveyor configured to transport the substrates along the discharge line at a speed, implementing an applicator configured to apply a desired amount of material to each of the substrates, implementing a pump configured to deliver material under pressure to the applicator, implementing a controller configured to receive the desired speed of the conveyor and control the speed of the conveyor to transport the substrates along the discharge line at the desired speed, determining by the controller using a control algorithm a target pressure of material to be delivered by the pump to the applicator to deliver the desired amount of material to each of the substrates, measuring an amount of material applied to a plurality of substrates by the pump, comparing the material applied for each substrate to the target value, and adjusting the pump pressure based on comparing the material applied for each substrate to the target value.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Patent Application No. 63 / 321,939, filed March 21, 2022, the entire contents of which are incorporated herein by reference.

[0002] (Technical field) FIELD OF THE DISCLOSURE This disclosure relates generally to systems and processes for controlling material application. [Background technology]

[0003] The amount of material, such as adhesive, applied to a substrate is often important. For example, ensuring that the right amount of adhesive is applied to a package can substantially affect the sale of the packaged goods. On the one hand, applying too much adhesive to a package can increase the cost of the packaged goods and can also reduce aesthetics due to adhesive "squeezing" out of the joint. In this regard, squeezing out can also result in adhesive, glue, or other material adhering to parts of the production line, causing breakdowns in the production line and downtime. On the other hand, applying too little adhesive can compromise the quality of the package and damage the packaged goods. Even minor defects can cause the entire production run of products to be rejected by a potential purchaser.

[0004] In this regard, customers want the same amount of dispensed material, such as adhesive, for each product. In other words, the amount of dispensed material, such as adhesive, per unit length and / or per product should be approximately the same regardless of the line speed of the system's dispense line and / or other factors described in Figure 9. Current systems do not provide sufficient control in applying adhesive to a substrate.

[0005] It is therefore desirable to provide a system configured to control material application. Summary of the Invention

[0006] The aforementioned needs are met in large part by the systems and processes described herein.

[0007] One embodiment includes a method of controlling material application in a material dispensing system, the method including implementing a conveyor configured to transport substrates along a discharge line at a predetermined speed, implementing an applicator configured to apply a desired amount of material to each substrate, implementing a pump configured to deliver material to the applicator at a predetermined pressure, implementing a controller configured to receive the desired speed of the conveyor and control the speed of the conveyor to transport the substrates along the discharge line at the desired speed, determining in the controller using a control algorithm a target pressure of material delivered by the pump to the applicator to deliver the desired amount of material to each substrate, measuring an amount of material delivered by the pump to a plurality of substrates, comparing the material applied for each substrate to a target value, and adjusting the pump pressure based on the comparison of the material applied for each substrate to the target value.

[0008] One embodiment includes a material dispensing system including a conveyor configured to transport substrates along a discharge line at a predetermined speed, an applicator configured to apply a desired amount of material to each substrate, a pump configured to deliver material to the applicator at a predetermined pressure, a controller configured to receive the desired speed of the conveyor and control the speed of the conveyor to transport the substrates along the discharge line at the desired speed, the controller configured to use a control algorithm to determine a target pressure of material delivered by the pump to the applicator to deliver the desired amount of material to each substrate, and a flow sensor configured to measure an amount of material delivered by the pump to the plurality of substrates, the controller configured to compare the material applied for each substrate to the target value to generate a comparison value, and the controller configured to adjust the pressure of the pump based on the comparison value.

[0009] In order that the present disclosure may be readily understood, aspects of the disclosure are illustrated by way of example in the accompanying drawings. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 shows a schematic diagram of an exemplary material dispensing system. [Diagram 2] FIG. 2 illustrates an exemplary system implementation diagram of a material dispensing system according to one embodiment of the present disclosure. [Figure 3A] FIG. 3A illustrates a material dispensing system closed loop process according to an embodiment of the present disclosure. [Figure 3B] FIG. 3B illustrates test results of applying material with a material dispensing system having closed loop flow control according to the present disclosure and without flow control. [Figure 4] FIG. 4 shows a schematic diagram of a material dispensing system according to an embodiment of the present disclosure. [Diagram 5] FIG. 5 illustrates an exemplary calibration process according to the present disclosure. [Figure 6] FIG. 6 illustrates a graph of an exemplary result of application of material by a material dispensing system after a calibration process according to the present disclosure. [Figure 7] FIG. 7 illustrates a schematic diagram of an exemplary material dispensing system. [Figure 8] FIG. 8 illustrates an exemplary schematic diagram of a control system according to the present disclosure. [Figure 9] FIG. 9 shows factors that cause the load to vary in the control system. [Figure 10] FIG. 10 shows a diagram of the general method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Like reference numbers are used in the drawings and the following detailed description to refer to like or similar parts.

[0012] The present disclosure is directed to precision dispensing and discloses a new paradigm in material application systems, such as hot melt systems, that uses flow measurement technology, such as flow meters, built-in flow meters, and the like.

[0013] The disclosed process and system are particularly valuable for installations that have variable production line speeds, however, the disclosed process and system can function for fixed production line speeds as well.

[0014] Since the amount of adhesive determines the bond strength, the customer wants the same amount of adhesive or other material on each product. In other words, the amount of adhesive per unit length should be the same regardless of the line speed. In particular, the customer wants to dispense a constant amount of adhesive or other material on each of multiple substrates or products. As further described below, the present disclosure generally refers to the flow rate of material dispensed, providing advanced teachings of the disclosed processes and systems capable of applying a continuous bead on an infinitely long product. However, this general reference teaching of flow rate is applicable to individual products and can be utilized by the disclosed systems and processes. In particular, the flow of material may be intermittent to skip gaps between multiple products or substrates being processed. For example, to apply two beads of material to a product or substrate in a line having one or more "gaps" between the products or substrates. This application of material may be referred to as a "pattern." When the application of material is separated or accounted for "by product," this may be referred to as an "added weight." The disclosed systems and processes are configured to provide a more consistent added weight per product for such intermittent application. However, having a more consistent add-on weight from product to product may not be sufficient for certain implementations. For example, the disclosed systems and processes may be configured to provide a uniform bead or application of material along the application length of a product or substrate. In this regard, non-uniform applications of material having the same total weight may be undesirable. In other words, an application of material that is a large glob at one end and a thin string at the other end may happen to have the same total weight. It would be advantageous to have this amount of adhesive directly set by the user and explicitly controlled in a closed loop.

[0015] However, in typical systems, the desired adhesive output amount is indirectly set by the user via pump pressure or motor speed to cause the system to provide the desired adhesive output. In this regard, these typical systems do not directly set this "additional" weight (or volume). Furthermore, in typical systems, the control loop is "open," i.e., there is no feedback and / or correction to maintain the desired output as conditions change.

[0016] Even with an existing system with flow measurement, the setup can be implemented as above, but with the convenience of a "flow readout". Even with a typical run-up, the system is open loop; therefore, the output will change as conditions change.

[0017] The disclosed system and process actively works to maintain a desired amount of adhesive applied to the product. In this regard, a list of factors that can vary the add-on amount is shown in FIG.

[0018] This disclosure utilizes various terms, and the meanings of these terms may vary. Accordingly, these terms are noted below with definitions, and may be used somewhat interchangeably in this disclosure, even though they are distinct. · Flow: What comes out of the system to be applied to the substrate. Flow Rate: Technically it applies to continuous flow. In this regard, the flow rate increases or decreases in proportion to the line speed in order to apply the same amount of product to each one. Addition: The amount of material, such as adhesive, that is applied to each of the products. A fixed amount is generally desired in this regard. The specific meaning of a term will be clear or should be inferred from the context in which it is used in this disclosure.

[0019] As described in this disclosure, the load can be one of the key quantities that determine the strength of the adhesive bond. In this regard, the disclosed system and process is configured to allow a user to directly input a "load" target value (i.e., set point) similar to a temperature set point. The disclosed system and process then operates to maintain a specified output using a closed loop feedback system based on the load (flow). In this regard, the load is the quantity that determines the adhesive bond.

[0020] For example, a system may be operated in the following manner: The system is operated at a temperature set point of 350°F and the adhesive has certain properties, such as viscosity, at that temperature. These properties affect the flow vs. pressure relationship. The system is adjusted so that the flow output (Qout) is as desired. At some point thereafter, the temperature set point of the system is changed slightly. This results in an unintentional change in the add weight delivered by the system of approximately 7% for a 5°F change in temperature using a typical packaging grade adhesive. The system output is close to accurate, but is no longer accurate. The disclosed system and process responds to the deviation in add weight by changing the pressure to bring the add back to the desired value at the new temperature.

[0021] Conceptually, the diagram shown in FIG. 10 conveys the high level concept. Implementing a system consistent with this diagram may seem attractive. However, implementing this directly involves some challenges, especially when line speeds are variable. Thus, the present disclosure implements a better performing and more practical system, as described further herein.

[0022] FIG. 1 shows a schematic diagram of an exemplary material dispensing system.

[0023] In particular, Figure 1 illustrates a material dispensing system 10 that may be configured to control the amount of material, such as adhesive, applied per substrate using closed-loop control. In some aspects, material dispensing system 10 may be implemented as a hot melt adhesive system. Hereinafter, the material used by material dispensing system 10 may be referred to as an adhesive. However, the disclosed embodiments of material dispensing system 10 are equally applicable to any type of material that may be applied to a substrate.

[0024] 1 , material dispensing system 10 may include a dispensing unit 12 and an application unit 20. Dispensing unit 12 may further include a material supply 14 configured to receive material 16, and a pump 44 configured to receive material 16 from material supply 14 and propel material 16 to application unit 20. Operation of dispensing unit 12 and / or application unit 20 may be controlled by a controller 100 and / or a user interface 24.

[0025] The application unit 20 may include one or more applicators 60 configured to apply material 16 to one or more substrates 62 disposed on a support. In some embodiments, the one or more applicators 60 may be guns, glue guns, adhesive guns, etc. In some embodiments, the application unit 20 may include a conveyor 80 configured to transport the one or more substrates 62 past the one or more applicators 60. Additionally, the application unit 20 may include hoses, nozzles, etc.

[0026] The conveyor 80 may be implemented as a conveyor belt, a pneumatic conveyor, a vibratory conveyor, a flexible conveyor, a spiral conveyor, a vertical conveyor, a motorized drive roller (MDR) conveyor, a roller conveyor, a heavy duty roller conveyor, a walking beam conveyor, a robotic conveyor, and the like. The conveyor 80 may be controlled by signals from the controller 100. In certain embodiments, the conveyor 80 may be configured to operate at multiple fixed speeds, variable speeds, and / or continuously variable speeds. Multiple fixed speeds, variable speeds, and / or continuously variable speeds may be considered quite different, but the disclosed systems and processes are configured to operate at each. For example, in some embodiments, the disclosed systems and processes may be configured to process multiple fixed speeds discretely, for example, using procedural instructions of operating parameters in conjunction with the calibration process 500 described below. Thus, one or more substrates 62 may be transported by the conveyor 80 along the coating line at multiple speeds and / or variable speeds on the discharge line 82. In particular, the discharge line 82 can operate at multiple and / or variable speeds to pass one or more substrates 62 through one or more application devices 60 for application of material 16 to the one or more substrates 62.

[0027] The pump 44 can be operatively controlled by the controller 100 to deliver the material 16 to the application unit 20 under pressure. In particular, the pump 44 can deliver the material 16 to the application unit 20 under variable pressure in response to input from the user interface 24. The pressure level of the material 16 generated by the pump 44 in response to the controller 100 results in the amount of the material 16 applied to the one or more substrates 62 by the one or more application devices 60. In other words, varying the pressure level of the material 16 varies the amount of the material 16 applied to the one or more substrates 62 by the one or more application devices 60. In some embodiments, the controller 100 can control the pump pressure. In this regard, the pump 44 can be implemented as a piston pump, and the control of the pump pressure can be performed by controlling the air pressure driving the pump 44. In this regard, by varying the air pressure supplied to the pump 44, the pump 44 varies the pressure level of the material 16, which can be an adhesive pressure, a fluid pressure, a liquid pressure, or the like.

[0028] Additionally, varying the speed of the discharge line 82 and / or conveyor 80 varies the time that the one or more substrates 62 are positioned to receive material 16 from the one or more applicators 60. Thus, varying the speed of the discharge line 82 and / or conveyor 80 varies the amount of material 16 applied from the one or more applicators 60 to the one or more substrates 62.

[0029] In this regard, a customer may wish to dispense the same amount of adhesive or other material 16 onto each of multiple substrates 62 or products. In other words, the amount of adhesive or other material 16 per unit length should be generally the same regardless of the line speed of the dispensing line 82 of the material dispensing system 10.

[0030] To this end, the material dispensing system 10 may implement one or more flow sensors 61 configured to generate a signal based on the flow information. The flow sensor 61 may be disposed within the material dispensing system 10 to measure the flow of the material 16. For example, the one or more flow sensors 61 may be disposed between the pump 44 and the one or more application devices 60. Additionally, the material dispensing system 10 may be configured to precisely vary the pressure of the material 16 applied to the one or more substrates 62 based on the line speed of the discharge line 82 and / or the conveyor 80. The disclosed process and system are highly advantageous when compared to prior art methods.

[0031] FIG. 2 illustrates an exemplary system implementation diagram of a material dispensing system according to one embodiment of the present disclosure.

[0032] In particular, FIG. 2 illustrates an exemplary system implementation diagram 200 of the material dispensing system 10. In this regard, the material dispensing system 10 may include a line speed input (LS) 202. In this regard, the line speed input (LS) 202 may be input to a run-up processing component 204 of the material dispensing system 10 to ensure that the material dispensing system 10 operates according to the speed of the conveyor 80 and / or the discharge line 82. The run-up processing component 204 may be configured to generate pressure according to the line speed of the conveyor 80 for further operation of the material dispensing system 10. However, as further described below, the output of the run-up processing component 204 may be subsequently corrected. Additionally, an exemplary embodiment of the run-up processing component 204 is described below in conjunction with FIGS. 4 and 5 and the description thereof.

[0033] The output of run-up processing component 204 is provided to a voltage-to-pressure processing component V→P 206. The output of pressure processing component V→P 206 may be a signal to operate pump 44. In some embodiments, pressure processing component V→P 206 may be implemented as an electronically controlled voltage-to-pressure converter and / or current-to-pressure converter.

[0034] The output of pressure processing component V→P206 may be input to piston pump processing component PP208. Piston pump processing component PP208 may be associated with pump 44 shown in FIG. 1. In some embodiments, the output of pressure processing component V→P206 may be air pressure PAIR230 for operating pump 44.

[0035] The output of the piston pump processing component PP208 may be input to a flow path processing component 210. The flow path processing component 210 relates to a hydraulic and / or adhesive flow path between the pump 44 and an output of the material dispensing system 10, such as one or more applicators 60. Further details of the flow path processing component 210 are described in relation to FIG. 4 and the adhesive path 404 shown in the system schematic 400. In particular, the output of the piston pump processing component PP208 may be a material hydraulic pressure PHYD 228, which may be the hydraulic pressure of the material 16.

[0036] One or more of the run-up processing component 204, the pressure processing component V->P 206, the piston pump processing component PP 208, the flow path processing component 210, and / or the like may operate within the material delivery system 10 as part of the run-up system 290.

[0037] The output from the flow path processing component 210 may be a continuous flow output QC 214. In this regard, the output from the flow path processing component 210 of the material dispensing system 10 may relate to the output of material 16 from one or more application devices 60 shown in FIG.

[0038] The output from the flow path processing component 210 can be monitored by a flow measurement system process FM 212. In this regard, the flow measurement system process FM 212 may include an adhesive tracking system (ATS), one or more flow sensors 61, etc. The output from the flow measurement system process FM 212 may be a flow rate QA-actual 216, which may be an actual weight add of material 16 applied to one or more substrates 62 by one or more application devices 60 of the material dispensing system 10.

[0039] 2, the material dispensing system 10 may be configured, at least in part, by the controller 100 and / or the user interface 24 to receive a desired add-on reference amount QA-ref 218. The desired add-on reference amount QA-ref 218 may be input to the user interface 24, the controller 100, another controller, etc. In this regard, the desired add-on reference amount QA-ref 218 may be a desired add-on or set point of material 16 to be applied by the material dispensing system 10 to one or more substrates 62.

[0040] The desired reference amount added QA-ref 218 and the flow rate QA-actual 216 may be combined at a combiner 292. In this regard, the value of the flow rate QA-actual 216 may be subtracted from the desired reference amount added QA-ref 218 to indicate an error or difference in the amount of material 16 applied by the material dispensing system 10 to one or more substrates 62 as shown in FIG. 1 or the amount of continuous flow rate output QC 214 as shown in FIG.

[0041] The error or difference output from the combiner 292 may be input to the controller K(s) 220. The controller K(s) 220 may be implemented by the controller 100 or may be implemented as a separate controller such as a proportional (P) controller, a proportional-integral (PI) controller, a proportional-derivative (PD) controller, a proportional-integral-derivative (PID) controller, etc.

[0042] The output from the controller K(s) 220 may be a pressure correction value ΔP 222. The pressure correction value ΔP 222 may be input to the combiner 294. In this regard, the pressure correction value ΔP 222 may be combined with the pressure signal from the run-up processing component 204. In particular, the pressure correction value ΔP 222 may be summed with the pressure signal from the run-up processing component 204. Thus, the output from the combiner 294 is the corrected pressure PCORR 224, which is the combined signal provided to the pressure processing component V→P 206.

[0043] As further shown in FIG. 2, in some embodiments, the material dispensing system 10 may implement a filter 226 as shown in the exemplary system implementation diagram 200. In this regard, the filter 226 may or may not be implemented by the material dispensing system 10 as desired and / or necessary. In this regard, the filter 226 may "smooth" the discrete and noisy output of the flow measurement system processing FM 212. A filter 226 in the feedback path may help or hurt the implementation of the material dispensing system 10. This helps to smooth the signal, but may also introduce a delay that may cause oscillations in the material dispensing system 10. Another filter implementation that may be useful is a filter placed between the flow set point, QA-ref, and the summing point in the material dispensing system 10. In particular, between the desired added reference amount QA-ref 218 and the combiner 294 in the material dispensing system 10. This can reduce and / or eliminate transients in the feedback loop of the material dispensing system 10. A transition time of 0.5 seconds (approximately a 0.1 second time constant) may be sufficient.

[0044] The method illustrated in the exemplary system implementation 200 shown in FIG. 2 can take advantage of flow path characteristics, such as flow resistance, determined in the embodiments of the present disclosure and its description shown in FIG. 4 and FIG. 5. The description states that this open-loop feed-forward path calculates the required flow almost exactly, but of course has a small error. The feedback loop of the exemplary system implementation 200 is closed on the flow rate variable ("add"), and the discrepancy can be overcome by negative feedback that applies a small correction (ΔP-corrected pressure PCORR 224) to the pressure from the pressure processing component V→P 206. In some embodiments, the closed-loop control of the material dispensing system 10 can be disabled by setting K(s)=0 for the controller K(s) 220 of the exemplary system implementation 200. In this case, the material dispensing system 10 is essentially an open-loop run-up system.

[0045] Testing / Results: An exemplary embodiment of the material dispensing system 10 operating consistent with the exemplary system implementation diagram 200 was implemented in software and preliminary testing produced impressive results. In this regard, the material dispensing system 10 operated such that the output changed smoothly as the load target (set point) was changed from a first mass to a second mass (e.g., 100 mg to 120 mg).

[0046] As an example of the closed loop adjustment capabilities of the material dispensing system 10, the gun temperature was changed and stabilized at each new set point as follows: 350°F->250°F->420°F->350°F. Pressure was automatically changed within the material dispensing system 10 as necessary by the disclosed algorithms such as the calibration process 500 and / or the material dispensing system closed loop process 600. Addition rate versus time was quite constant or "flat" and only changed + / - 5 mg despite a rather excessive 170°F temperature change within the gun.

[0047] Further tests of the material dispensing system 10 were attempted where the pressure was changed and the pattern timing relative to the line speed was altered. The disclosed closed loop control of the material dispensing system 10 was able to regulate the process and significantly reduce the output fluctuations that would occur with open loop.

[0048] The disclosed system and process provide many advantages. For example, the settings received and controlled by the material dispensing system 10 match what the customer cares about, i.e., the amount of material 16, such as adhesive, to be applied to the substrate 62 and / or product. Additionally, the disclosed embodiments of the material dispensing system 10 improve the quality of the adhesive joint and the final product. Additionally, the disclosed embodiments of the material dispensing system 10 provide improved economy and / or reduced costs to the user because the output of the material dispensing system 10 is tightly controlled and little or no excess material is needed to avoid running out of adhesive as conditions change. Additionally, the disclosed embodiments of the material dispensing system 10 provide greater convenience in that the complexity of the system in the material dispensing system 10 is "hidden" from the user. Additionally, the disclosed embodiments of the material dispensing system 10 provide improved direct control of key variables under closed loop feedback control within the material dispensing system 10. Additionally, the disclosed embodiments of the material dispensing system 10 build upon improved run-up systems with traditional controls. Additionally, the disclosed embodiments of the material dispensing system 10 can utilize diagnostics. Additionally, the disclosed embodiments of the material dispensing system 10 operate on both fixed and variable speed lines.

[0049] As shown in Figure 10, a "simple" closed loop of flow without considering line speed looks attractive at first glance. Such a system may work quite well for a fixed speed line. However, if there is nonlinearity in the control loop, the system does not know where it is operating on the run-up curve.

[0050] FIG. 3 illustrates a material dispensing system closed loop process according to one embodiment of the present disclosure.

[0051] 3 illustrates a material dispensing system closed loop process 600 that may be performed by the material dispensing system 10, the controller 100, and / or the like. Initially, the material dispensing system closed loop process 600 may include receiving 602 a line speed input, which may include a line speed input (LS) 202, as described with reference to FIG.

[0052] Additionally, the material dispensing system closed loop process 600 may include receiving 604 a desired added reference amount. In particular, the material dispensing system closed loop process 600 may include receiving 604 a desired added reference amount, which may include the desired added reference amount QA-ref 218 described with reference to FIG.

[0053] Additionally, the material delivery system closed loop process 600 may include generating a pressure responsive to a line speed input 606. In this regard, the generating a pressure responsive to a line speed input 606 may include any one or more of the pressure processing component V→P 206, the piston pump processing component PP 208, the flow path processing component 210, the corrected pressure PCORR 224, the material hydraulic pressure PHYD 228, and the air pressure PAIR 230.

[0054] Next, the material delivery system closed loop process 600 may include monitoring 608 an output from the flow measurement system. Monitoring 608 an output from the flow measurement system may include obtaining flow QA-actual 216 from the filter 226 and / or the flow measurement system process FM 212.

[0055] Additionally, the material delivery system closed loop process 600 includes determining 610 an error or difference between the desired reference amount added and the output by the material delivery system. Determining 610 an error or difference between the desired reference amount added and the output by the material delivery system may include the output of a combiner 292 that compares the desired reference amount added QA-ref 218 to the flow rate QA-actual 216.

[0056] Additionally, the material dispensing system closed loop process 600 may include generating a pressure correction value and performing pressure correction 612. In some embodiments, generating a pressure correction value and performing pressure correction 612 may include generating a pressure correction value ΔP 222, a corrected pressure PCORR 224, and / or the like.

[0057] FIG. 3B illustrates test results of applying material with a material dispensing system having closed loop flow control according to the present disclosure and without flow control.

[0058] In particular, Figure 3B shows test results of application of material 16 by a material dispensing system 10 implementing a material dispensing system closed loop process 600 in accordance with the present disclosure, as indicated by the line labeled Flow Control (FC). Figure 3B shows test results of application of material 16 by a material dispensing system 10 without flow control in accordance with the present disclosure, as indicated by the line labeled No Flow Control (NFC). As shown in Figure 3B, the Y-axis is the weight of material 16 added (grams). The X-axis is time.

[0059] As shown in FIG. 3B, the material dispensing system 10 was operated with a temperature change of 50° F. as an example of the closed loop adjustment function of the material dispensing system 10. The pressure was automatically changed in the material dispensing system 10 as necessary by the disclosed algorithms such as the calibration process 500 and / or the material dispensing system closed loop process 600. Over time, an additional weight of material 16 was initially applied by the material dispensing system 10 executing the material dispensing system closed loop process 600, which temporarily deviated by about 16%, and then returned to a value closer to the initial value. Execution of the material dispensing system closed loop process 600 returned the additional weight to near 1200 mg after about time 50. Meanwhile, application of material 16 by the material dispensing system 10 without flow control (NFC) resulted in a deviation of about 50% and the deviation remained unchanged.

[0060] Thus, the material dispensing system 10 implemented with the material dispensing system closed loop process 600 may operate to provide an appropriate amount of material 16, a more consistent amount of material 16, an improved consistent amount of material 16, etc., on a substrate 62 or product, respectively, relatively independent of the operating parameters of the material dispensing system 10 as shown in Figure 9. Additionally, the material dispensing system 10 implemented with the material dispensing system closed loop process 600 may be used in a variety of systems having linear and / or non-linear components.

[0061] In further aspects of the present disclosure, the material dispensing system 10 and / or the controller 100 may be implemented with a different controller having a "velocity type" PID or integrator. In further aspects of the present disclosure, the material dispensing system 10 and / or the controller 100 may be implemented with "signal processing" in either hardware or software. In further aspects of the present disclosure, the material dispensing system 10 may be implemented with a system having a flow measurement section with one or more flow sensors 61 built-in. In further aspects of the present disclosure, the material dispensing system 10 may be implemented with an external flow meter for one or more flow sensors 61. In further aspects of the present disclosure, the material dispensing system 10 and / or the controller 100 may be implemented with other types of control laws including non-linear control laws, gain scheduled control laws, adaptive control laws, neural network control laws, fuzzy logic control laws, machine learning control laws, etc. In further aspects of the present disclosure, the material dispensing system 10 may be implemented with a slightly different method for continuous flow. In a further aspect of the present disclosure, the material dispensing system 10 may be implemented such that the desired flow rate Qdesired and / or the desired additive reference amount QA-ref 218 are derived or calculated as a scale function of the line speed. In other words, the material dispensing system 10 may be implemented such that the flow rate is proportional to the line speed.

[0062] FIG. 4 shows a schematic diagram of a material dispensing system according to an embodiment of the present disclosure.

[0063] In particular, Figure 4 illustrates a system schematic 400, which may be a system schematic of the material dispensing system 10 illustrated in Figure 1. The system schematic 400 is shown as having a material source 402 operating at a pressure P. The material source 402 may include any one or more of the dispensing unit 12, the material supply 14, the material 16, the pump 44, and / or the like.

[0064] Material may flow through the material dispensing system 10 along an adhesive path 404. In particular, material may flow through the material dispensing system 10 along the adhesive path 404 in the dispensing unit 12, from the dispensing unit 12 to the application unit 20, through the application unit 20 onto one or more substrates 62. Additionally, the material dispensing system 10 may connect along the adhesive path 404 to one or more components 406 having a linear relationship of flow rate Q to pressure. In this regard, the one or more components 406 are illustrated with a flow rate Q proportional to pressure P or a flow rate Qα to pressure P. In this regard, proportionality or proportionality may include other factors such as a scaling constant and / or the like. An example of one or more components 406 that may have a linear relationship of flow rate Q to pressure may include a hose of the application unit 20.

[0065] Additionally, the material dispensing system 10 may be connected along the adhesive pathway 404 to one or more components 408 having a non-linear relationship of flow rate Q to pressure. For example, the one or more components 408 may have a non-linear relationship such that the flow rate Q is proportional to the square root of the pressure. In this regard, the one or more components 406 are illustrated with a flow rate Qα where the flow rate Q is proportional to the square root of the pressure P, i.e., with respect to the square root of the pressure P. An example of the one or more components 408 that may have a non-linear relationship may include a nozzle of the application unit 20. Additionally, it is contemplated that the one or more components may have another non-linear relationship of flow rate Q to pressure P.

[0066] Additionally, it should be noted that the dispensing unit 12 can implement one or more components 406 and / or one or more components 408 (not shown), the application unit 20 can implement one or more components 406 and / or one or more components 408 as shown, and / or both the dispensing unit 12 and the application unit 20 can implement one or more components 406 and / or one or more components 408 (not shown). One or more of the material source 402, adhesive pathway 404, one or more components 406, one or more components 408, and / or the like may be embodied by one or more components of the material dispensing system 10 shown in FIG.

[0067] Thus, the material dispensing system 10 may have a non-linear relationship between pressure and line speed. In this regard, the disclosed process and system address the non-linear relationship between pressure and line speed by characterizing and / or modeling the non-linear flow resistance of the dispensing unit 12, the application unit 20, the one or more components 406, the one or more components 408, the adhesive path 404, and / or the like with a minimum of three points. In this regard, it is known that the flow resistance, or pressure vs. flow rate relationship, is non-linear because it is a combination of pressure drops through the material dispensing system 10, not all of which are linear.

[0068] The degree of nonlinearity may be affected by the relative contributions of many factors, including system configuration factors including flow paths within the material dispensing system 10, chemical formulation of the material 16, application temperature of the material 16, viscosity of the material 16, one or more internal melter flow paths with an ATS (adhesive tracking system), one or more internal melter flow paths without an ATS, one or more internal melter flow paths with an ATP, one or more melter flow paths without an ATP, and / or the like; adhesive factors including one or more of chemical formulation, application temperature, viscosity, and / or the like; hose factors including one or more of hose length, hose diameter, hose construction, and / or the like; hose construction may include factors such as heater or type of heater, type of insulation, thermal efficiency, type of fitting, type of barrier material, and / or the like; nozzle factors including one or more of nozzle engagement such as nozzle diameter, nozzle length, and / or the like, and other system dependent factors.

[0069] One or more of these aforementioned factors, as well as other factors, may be linear, such as one or more components 406 of the material dispensing system 10. However, some factors associated with certain components of the material dispensing system 10, such as one or more components 408, which may include nozzles, in particular, may have a flow rate proportional to the square root of the pressure (SQRT), which is non-linear.

[0070] For example, curve fits to actual pressure data were obtained in a laboratory at various line speeds for an exemplary embodiment of material dispensing system 10. The table below illustrates that certain non-linear terms or aspects of the components of material dispensing system 10 can have larger magnitudes and / or can vary more significantly as compared to the linear terms of the components of material dispensing system 10. [Table 1]

[0071] Assuming a "linear" relationship is a strong assumption and may not fit all cases of embodiments of material dispensing system 10. In limited cases, assuming a "linear" relationship may provide "good enough" data for control of material dispensing system 10. On the other hand, assuming a "non-linear" relationship is a weaker assumption and may accommodate a wide range of systems and processes associated with embodiments of material dispensing system 10, including those that are linear or nearly linear. Thus, the disclosed processes for implementation in material dispensing system 10 may be more universally applicable.

[0072] FIG. 5 illustrates an exemplary calibration process according to the present disclosure.

[0073] In particular, FIG. 5 illustrates a calibration process 500 for implementation in the material dispensing system 10. In particular, the calibration process 500 may be implemented by the controller 100 and / or the user interface 24 and may be utilized in conjunction with the implementation of a material dispensing system closed-loop process 600. In particular, in some embodiments, the calibration process 500 may be utilized to induce a non-linear run-up to bring the material dispensing system 10 as close as possible to a desired operation, after which the material dispensing system closed-loop process 600 may be executed to fine-tune the material dispensing system 10. In some embodiments, the material dispensing system 10 may operate with the material dispensing system closed-loop process 600 and without the calibration process 500. In this regard, operation of the material dispensing system 10 utilizing a closed-loop implementation of the material dispensing system closed-loop process 600 may not require the implementation of the calibration process 500.

[0074] Initially, the calibration process 500 may include operating 502 the material dispensing system 10 at the intended application temperature for the selected material. In this regard, the controller 100 and / or the user interface 24 may enable controlled operation of the material dispensing system 10 at the intended application temperature of the material 16, as described in the embodiment of the material dispensing system 10 described in connection with FIG.

[0075] The calibration process 500 may then include operating 504 the material dispensing system 10 at a plurality of different line speeds, where for each line speed, the pressure may be adjusted by the controller 100 and / or the user interface 24 to achieve a flow rate proportional to the line speed. In some embodiments, the calibration process 500 may include operating the material dispensing system 10 at three different line speeds, four different line speeds, five different line speeds, six different line speeds, seven different line speeds, eight different line speeds, nine different line speeds, ten different line speeds, eleven different line speeds, and / or twelve different line speeds. In some embodiments, the calibration process 500 may include operating the material dispensing system 10 at 3 to 12 different line speeds, 3 to 4 different line speeds, 3 to 5 different line speeds, 3 to 6 different line speeds, 3 to 7 different line speeds, 3 to 8 different line speeds, 3 to 9 different line speeds, 3 to 10 different line speeds, 3 to 11 different line speeds, and / or 3 to 12 different line speeds. In some embodiments, the calibration process 500 may include operating the material dispensing system 10 at more than two different line speeds. Because the material dispensing system 10 can measure the output of the material 16 using the flow sensor 61, the material dispensing system 10 can be automated by aspects of the present disclosure, such as an embodiment of the material dispensing system closed loop process 600, for further utility and / or convenience. In this regard, the controller 100 and / or the user interface 24 may enable controlled operation of the material dispensing system 10 at multiple different line speeds for the conveyor 80, the discharge line 82, and / or the like. Further, the controller 100 and / or user interface 24 may enable controlled operation of the pump 44 at different pressures to achieve a desired pressure of the material 16, to achieve a flow rate of the material 16 applied to the one or more substrates 62, and to achieve a desired constant amount of the material 16 applied to the one or more substrates 62.

[0076] In particular, the process can control the pressure Pn of the material 16 controlled by the pump 44 relative to the line speed LSn of the conveyor 80 and / or discharge line 82 to obtain a flow rate Qn of the material 16 applied to the one or more substrates 62 and / or a flow rate expressed as an add-on amount QAn of an individual product of the material 16 applied to the one or more substrates 62 to achieve a desired constant amount of the material 16 applied to the one or more substrates 62. Each of the different line speeds of the conveyor 80 and / or discharge line 82 and pressures of the material 16 and / or pump 44 can be recorded and / or stored for further processing in connection with the calibration process 500.

[0077] In this regard, the material dispensing system 10 can be operated at a first line speed (LS1) by the conveyor 80 and / or discharge line 82 responsive to the controller 100 and / or user interface 24, and a first pressure (P1) can be adjusted by the pump 44 responsive to the controller 100 and / or user interface 24 to achieve a first flow rate (Q1) proportional to the first line speed (LS1) to achieve a desired constant amount of material 16 applied to one or more substrates 62. For example, go for LS1=10 and adjust the pressure P1 such that the flow rate Q1=Q or (addition amount) is QA.

[0078] The material dispensing system 10 can then be operated at a second line speed (LS2) by the conveyor 80 and / or discharge line 82 responsive to the controller 100 and / or user interface 24, and the second pressure (P2) can be adjusted by the pump 44 responsive to the controller 100 and / or user interface 24 to achieve a second flow rate (Q2) proportional to the second line speed (LS2) to achieve a desired constant amount of material 16 applied to the one or more substrates 62. For example, go to LS2=30 and adjust the pressure P2 such that the flow rate Q2=3Q or (addition amount) is QA.

[0079] Finally, the material dispensing system 10 can be operated at a third line speed (LS3) by the conveyor 80 and / or the discharge line 82 responsive to the controller 100 and / or the user interface 24, and the third pressure (P3) can be adjusted by the pump 44 responsive to the controller 100 and / or the user interface 24 to achieve a third flow rate (Q3) proportional to the third line speed (LS3) to achieve a desired constant amount of material 16 applied to the one or more substrates 62. For example, go for LS3=50 and adjust the pressure P3 so that the flow rate Q3=5Q or (addition rate) is QA. However, it should be noted that the calibration process 500 can be performed at n different line speeds, pressures, and flow rates to achieve a desired constant amount of material 16 applied to the one or more substrates 62. In some embodiments, n can be 3 or more. In some embodiments, n can be 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12.

[0080] Thus, the calibration process 500 operates the conveyor 80 and / or discharge line 82, responsive to the controller 100 and / or user interface 24, at different speeds and the pump 44, responsive to the controller 100 and / or user interface 24, at different pressures to determine the flow rate to achieve a desired constant amount of material 16 applied to one or more substrates 62, regardless of the speed of the conveyor 80 and / or discharge line 82.

[0081] The calibration process 500 can then generate 506 a non-linear control algorithm of the operating parameters for operating the system. Specifically, the calibration process 500 models and / or generates a control algorithm utilizing different speeds of the conveyor 80 and / or discharge line 82 along with the determined pressure to achieve a desired constant amount of material 16 applied to the one or more substrates 62 regardless of the speed of the conveyor 80 and / or discharge line 82. More specifically, the calibration process 500 models and / or generates constants used in the non-linear control algorithm utilizing different speeds of the conveyor 80 and / or discharge line 82 along with the determined pressure to achieve a desired constant amount of material 16 applied to the one or more substrates 62 regardless of the speed of the conveyor 80 and / or discharge line 82. Additionally or alternatively, this aspect of the calibration process 500 can utilize machine learning, artificial intelligence, and / or the like.

[0082] Finally, the calibration process 500 may include operating 508 the material dispensing system 10 with the non-linear control algorithm. In particular, the algorithm generated by the calibration process 500 may be utilized by the material dispensing system 10 for subsequent operation to ensure that the material dispensing system 10 applies a desired consistent amount of material 16 to the one or more substrates 62 regardless of the speed of the conveyor 80 and / or the dispensing line 82.

[0083] In this regard, by receiving, by the controller 100 and / or the user interface 24, an associated operating pressure of the material 16 for each of a plurality of line speeds of the conveyor 80, the controller 100 is configured to generate a non-linear control algorithm during operation of the material dispensing system 10 at the plurality of line speeds to provide a desired amount of material applied to the substrate 62. Additionally, the material dispensing system 10 and / or the controller 100 may be configured to store an association between each of a plurality of line speeds of the conveyor 80 and an associated operating pressure of the material 16.

[0084] Additionally, material dispensing system 10 may implement user interface 24 to receive a desired speed of conveyor 80. Additionally, controller 100 may receive the desired speed from user interface 24 to control the speed of conveyor 80. Additionally, controller 100 and / or calibration process 500 may determine a target pressure for material 16 to be delivered by pump 44 to one or more application devices 60 based on the desired speed received at user interface 24 and utilize a non-linear control algorithm generated by calibration process 500 to deliver the desired amount of material to each of substrates 62.

[0085] In this regard, it is noted that the calibration procedure performed as calibration process 500 is simple and easy to understand. At each point in the execution of calibration process 500, the operation is the same and makes sense to achieve "addition matching" or "flow proportionality." In some embodiments, material dispensing system 10 may implement a piston pump system in which air pressure is controlled by material dispensing system 10 to vary hydraulic pressure.

[0086] The calibration process 500 can be utilized in many different ways. In one embodiment, the calibration process 500 may be performed using three points across the dispense range (excluding a zero flow condition such as line speed=0). Additionally, the calibration process 500 may be performed to fit a curve to the three points where the flow rate Q is proportional to the line speed. Similarly, if "addition rate" (amount dispensed per product) is the criterion, the add-on rate should be the same at each line speed.

[0087] In one embodiment, execution of the calibration process 500 may result in three equations with three unknowns (constants A, B, and C). P0=A*SQRT(LS0)+B*LS0+C P1=A*SQRT(LS1)+B*LS1+C P2=A*SQRT(LS2)+B*LS2+C Where: LS=Line Speed P=pressure The constants A, B, and C can determine the shape of the pressure vs. line speed relationship (curve).

[0088] In some embodiments, the calibration process 500 may execute an algorithm that utilizes matrices to determine the constants. Thus, the solution is: X=M -1 *P. Where:

number

number

number

number

[0089] The controller 100 may execute a calibration process 500 to solve for the constants A, B, and C. The material dispensing system 10 then operates in conjunction with the controller 100 to execute an algorithm to operate the conveyor 80 and / or the dispensing line 82 of the material dispensing system 10 at any line speed, and the controller 100 may calculate the appropriate pressure of the material 16 to ensure a constant application rate of the material 16 to one or more substrates 62. Because the matrices are small, these calculations may also be performed separately by the controller 100 and / or another computer without the use of a matrix calculation software library. However, the controller 100 and / or another computer may operate using a matrix calculation software library. In some embodiments, the controller 100 and / or another computer may operate using a matrix calculation software library that may be utilized in implementations where n is greater than 3.

[0090] FIG. 6 illustrates a graph of an exemplary result of application of material by a material dispensing system after a calibration process according to the present disclosure.

[0091] In particular, FIG. 6 illustrates a graph of an exemplary result of application of material 16 by material dispensing system 10 and / or controller 100 after performing calibration process 500. In this regard, FIG. 6 illustrates a graph 300 of the results of application of material 16 by material dispensing system 10 to one or more substrates 62 with the material dispensed on the vertical or y-axis in grams per foot (g / ft) and the line speed on the horizontal or x-axis in feet per minute (ft / min). In this regard, line 302 and associated data points indicate that the amount of material 16 applied by material dispensing system 10 to one or more substrates 62 in response to controller 100 performing calibration process 500 remains substantially the same even as the line speed of conveyor 80 and / or discharge line 82 of material dispensing system 10 increases or decreases along the x-axis. In this regard, line 302 should be approximately flat or as flat as possible. Additionally, note that the results graph 300 shown in FIG. 6 includes noisy / unstructured measurement error data points 304 and exhibits a percent error of less than 10%.

[0092] The disclosed system and process implementation of the material dispensing system 10 and / or calibration process 500 provides excellent accuracy in the application of material 16 to one or more substrates 62. Moreover, the disclosed system and process implementation in the material dispensing system 10 is relatively simple. The disclosed process and system implementation of the material dispensing system 10 and / or calibration process 500 accommodates various combinations of hose, nozzle sizes, and / or the like in the material dispensing system 10 by modeling, characterizing, and / or the like, pressure versus flow relationships in the material dispensing system 10 utilizing the calibration process 500.

[0093] The disclosed process and apparatus implementations accommodate, with few assumptions, both linear and non-linear system implementations of the material dispensing system 10. The disclosed process and system implementations of the material dispensing system 10 and / or calibration process 500 fully extrapolate outside the range of calibration.

[0094] The disclosed process and system implementation of material dispensing system 10 and / or calibration process 500 takes into account application conditions such as various materials, adhesives, temperatures, and / or the like.

[0095] The disclosed process and system implementation of material dispensing system 10 and / or calibration process 500 allows for good product production over a wide range of line speeds, including speedups and slowdowns, which can reduce waste of both material 16 and one or more substrates 62. The disclosed process and system implementation of material dispensing system 10 can also match production rates to upstream and downstream production processes.

[0096] The disclosed system and process has been implemented and found to work well, as shown in the graph depicted in Figure 6. Nevertheless, various alternative embodiments are possible. Additionally, the disclosed system and process for performing the calibration process 500 can approximate curves with polynomials of second order or higher.

[0097] The disclosed systems and processes may utilize three or more points and perform a "least squares" fit as part of the calibration process 500, which can reduce inaccuracies due to measurement noise. The disclosed systems and processes may also use other types of curve-fitting based formulations to perform the calibration process 500. The disclosed systems and processes may be performed in conjunction with the calibration process 500 with or without a matrix calculation software library.

[0098] Thus, the material dispensing system 10 is configured to execute a non-linear algorithm that offsets the non-linearity of the material dispensing system 10 to provide a flow rate of the material 16 that increases in proportion to the line speed of the conveyor 80. This provides an appropriate amount of material 16, a more consistent amount of material 16, an improved consistency of amount of material 16, etc., to each of the substrates 62 or products relatively independent of the line speed of the conveyor 80. Additionally, the material dispensing system 10 may use sensors and controllers to control adhesive consumption in conjunction with the calibration process 500. The material dispensing system 10 may be configured to apply a consistent amount of adhesive (e.g., "add-on" weight or volume) to the substrate by executing the calibration process 500. The material dispensing system 10 may be configured to receive a target amount of adhesive to be applied per substrate, and the calibration process 500 may be executed to continuously control the components of the material dispensing system 10 accordingly. Thus, the material dispensing system 10 may ensure that sufficient adhesive is applied by application of the calibration process 500, while improving the economy and aesthetics of adhesive application by reducing waste.

[0099] It will be understood that the material dispensing system 10 shown and described herein is merely exemplary, and that the control of the amount of adhesive applied per substrate is applicable to other hot melt adhesive systems. For example, the material dispensing system 10 may include a separate hopper type melter, but may also be a hot melt adhesive system that includes a grid reservoir type melter.

[0100] The material dispensing system 10 may apply a material, such as an adhesive, to any type of substrate, such as packaging, electronics, hygiene products, industrial products, consumer goods, and / or paper products. For example, packaging may include boxes, envelopes, and / or the like. Electronics may include semiconductors, circuit boards, and / or the like. Although described above with respect to adhesives, the material dispensing system 10 may be configured to apply many other materials, such as food products.

[0101] FIG. 7 illustrates a schematic diagram of an exemplary material dispensing system.

[0102] 7, the dispensing unit 12 may further include a manifold 18 connected to the material supply 14. In some embodiments, the material supply 14 may be configured as an adhesive material source and the material 16 may be an adhesive material. Thus, the material supply 14 may be configured to receive and melt a solid or semi-solid hot melt adhesive material.

[0103] The material supply 14 may include a hopper 26 configured to contain the material 16 in a solid or semi-solid state, and a melter 28 having a heating element 30 and a reservoir 32, where the heating element 30 is configured to melt the material 16 and the melted material 16 is contained in the reservoir 32. In other embodiments, the material supply 14 may not include the heating element 30, which may instead be within the manifold 18. The material supply 14 may also include one or more side walls 34 and a removable cover 36 configured to contain the hopper 26. The reservoir 32 may be coupled to a rigid or flexible flow path 40 that may pass the material 16 to the manifold 18. The rigid or flexible flow path 40 may have a minimum or near zero length.

[0104] Manifold 18 may be attached to sidewall 34 of material supply 14 and may be coupled to pump 44. Pump 44 may be configured to pump material 16 from material supply 14 into manifold 18, where material 16 may be split into separate streams.

[0105] In some embodiments, the pump 44 may include a housing 46 defining a piston chamber that receives a piston 54. A pump rod 56 may extend downwardly from the piston 54 into the manifold 18 to pressurize the material 16. The piston 54 may divide the piston chamber into an upper chamber 50 and a lower chamber 52. The upper chamber 50 may selectively receive pressurized air from a first actuator 48, and the lower chamber 52 may selectively receive pressurized air from a second actuator 49. Thus, the first actuator 48 and the second actuator 49 may be selectively actuated to provide pressurized air in the upper chamber 50 to push an upper side of the piston 54 to move the piston 54 and the pump rod 56 in one direction, and then provide pressurized air in the lower chamber 52 to push a lower side of the piston 54 to move the piston 54 and the pump rod 56 in another direction. This reciprocating motion of the pump rod 56 may repeatedly draw the material 16 from the material supply 14 into the manifold 18 and expel the material 16 from the manifold 18. The piston 54 and / or the pump rod 56 may include one or more sensors (not shown) to determine material flow rate. The first actuator 48 and the second actuator 49 may include solenoids, spool valves, and / or any other type of actuator configured to provide pressurized air. Thus, the pump 44 may be controlled by the pressure level of pressurized air received from an air source and provided to the pump 44 by the first actuator 48 and the second actuator 49, as shown in FIG. 7.

[0106] In some embodiments, pump 44 may alternatively be actuated by one or more magnetic moving bodies. Although described above as a piston pump, pump 44 may be any type of pump, including an air piston pump and / or the like.

[0107] In some embodiments, the pump 44 may include or be coupled to a device for controlling the output hydraulic pressure of the material 16. In some embodiments, the pump 44 may include or be coupled to a pneumatically operated voltage-to-pressure or current-to-pressure device for controlling the air pressure to the pump 44 such that the output hydraulic pressure is proportional to the input air pressure. In some embodiments, the pump 44 may include a pressure control valve in a recirculation path parallel to the output path, which may be either pneumatically or electrically regulated. In some embodiments, a pressure reducing regulator may be directly in series with the output flow path providing a substantially constant pressure source. In some embodiments, the substantially constant pressure source may only be substantially constant at one line speed. In some embodiments, the pressure reducing regulator may facilitate many variations in the material dispensing system 10. In some embodiments, the pressure reducing regulator may be air controlled. In this regard, as the air pressure changes relative to the pressure reducing regulator, the pressure also changes. In some embodiments, the air-to-adhesive pressure ratio of the pump 44 may be greater than the air-to-adhesive pressure of the pressure reducing regulator. As a non-limiting example, the air to adhesive pressure ratio of the pump 44 may typically be 14:1, while the air to adhesive pressure of the pressure reducing regulator may be lower, such as 10:1. As a further non-limiting example, with an air pressure of 50 PSI, the pump produces 700 PSI and the regulator provides 500 PSI. The "headroom" (200 PSI in this example) provides a differential for the regulator to operate. The disclosed process and system are configured to operate with embodiments of the material dispensing system 10 that do not implement a pressure reducing regulator, as well as embodiments of the material dispensing system 10 that do implement a pressure reducing regulator, which is an advantage of the disclosed system and process.

[0108] The manifold 18 may include one or more ports 58 that generate a flow of the material 16. The manifold 18 may include a flow sensor 59 for measuring the flow rate of the material 16 through the manifold 18. The flow sensor 59 may generate a signal indicative of flow information. For example, the flow sensor 59 may be an encoder that measures the rotation of a shaft in the manifold 18 that the flow of the material 16 rotates. The flow sensor 59 may additionally or alternatively be at an outlet of the manifold 18, and the flow sensor 59 may include multiple ports for attachment to hoses 57. Exemplary manifolds including flow sensors suitable for the present disclosure are disclosed in U.S. Pat. No. 6,857,441 and U.S. Provisional Patent Application No. 62 / 318,114, filed April 4, 2016, the disclosures of which are incorporated herein by reference. Other manifolds, flow sensors, or flow measurement devices may be used, and the specific configurations of the manifold 18 and flow sensor 59 described herein provide exemplary illustrations only. Additionally, a pressure sensor may be used in place of or in combination with the flow sensor 59. The flow sensor 59 is part of a control system associated with the pump 44, as described below.

[0109] One or more ports 58 of the manifold 18 may be fitted with a hose 57 connected to the application unit 20. One or more flow sensors 61 may be fitted to the hose 57 and configured to generate a signal based on the flow information. The flow sensors 61 may be arranged in series with the hose 57. For example, the material dispensing system 10 may include multiple small embodiments of the flow sensor 61 arranged in series with each hose 57. In some aspects, the flow sensor 61 may include a rotary encoder arranged inside the hose 57 and may be configured to generate a signal based on the fluid flow rate of the material 16. In some aspects, the flow sensor 61 may be arranged outside the hose 57 (e.g., as shown in FIG. 7) and may be configured to measure the flow rate by a laser-based interferometer and / or a Doppler-based meter and generate a signal.

[0110] The applicator 60 may include one or more adhesive dispensing modules 66 mounted on an applicator body 68 having an applicator heater 70 on a support 64. The adhesive dispensing modules 66 of the applicator 60 may provide a nozzle for dispensing the material 16. In some embodiments, one or more flow sensors may be disposed in and / or on the applicator 60 and configured to generate a signal based on flow information of the portion where the material 16 is to be applied. For example, the flow sensors of the applicator 60 may be configured to detect the flow rate of the material 16 entering the applicator 60, through the applicator 60, and / or exiting the nozzle, and / or the dimensions of the nozzle. The flow sensors may be disposed at the inlet of the applicator 60 and / or at each of the nozzles depending on the desired accuracy.

[0111] The application unit 20 may include one or more substrate sensors 72 configured to detect a plurality of substrates 62 being transported on the conveyor 80 and / or having the material 16 applied thereto. In some embodiments, the substrate sensors 72 may be implemented as optical sensors configured to detect breaks in a light beam induced by the passage of a substrate 62. It may also be contemplated that the substrate sensors 72 may include weight sensors configured to detect the passage of a substrate 62 based on a weight applied to the substrate sensor 72.

[0112] Although material dispensing system 10 is shown in FIG. 7 as including a single application unit disposed adjacent to a single embodiment of dispensing unit 12, a different number of embodiments of dispensing units 12, application units 20, coating devices 60, supports 64, conveyors 80, and / or the like may be used in any configuration.

[0113] FIG. 8 illustrates an exemplary schematic diagram of a control system according to the present disclosure.

[0114] FIG. 8 illustrates an exemplary schematic diagram of a control system 11 that may be implemented in the exemplary embodiment of the material dispensing system 10 of FIG. 7. The control system 11 may include one or more controllers 100 in communication with one or more sensors and / or actuators. For example, the controller 100 may be in wired and / or wireless communication with the user interface 24, the first actuator 48, the second actuator 49, one or more flow sensors 59, 61, the substrate sensor 72, the conveyor 80, etc. The controller 100 may include one or more computers, servers, modules and / or programmable circuits that receive various sensor inputs and generate control signals, for example, for controlling the pump 44 via the first actuator 48 and the second actuator 49. The controller 100 may be configured to receive a target application rate setpoint of the material 16 (e.g., via the user interface 24) or store pre-set application rate setpoints of the material 16 and control the pump 44. For example, the controller 100 may be configured to receive a target amount of the material 16 applied to each of the substrates 62. The controller 100 may be implemented in many different forms and configurations, including, but not limited to, a programmable microcontroller implementing an appropriate control algorithm, for example, a closed loop proportional-integral-derivative (PID) controller control methodology, a programmable logic controller (PLC), discrete circuit components, an application specific integrated circuit (ASIC) type controller, etc.

[0115] The controller 100 may receive flow information from one or more sensors. For example, in some embodiments, the control system 11 may include a flow sensor 59 for measuring the flow rate of the material 16 through the manifold 18. The control system 11 may additionally or alternatively include other sensors for detecting the flow rate information, which may be processed to determine the flow rate of the material 16 to the melter 28. The control system 11 may include a flow sensor 61 configured to detect the flow rate of the material 16 through one or more hoses 57 to the applicator 60. The control system 11 may further include a flow sensor operably connected to the applicator 60 and configured to detect the material 16 flowing from the applicator 60 onto one or more substrates 62. The detected flow rate information of the material 16 may include flow rate, pressure, temperature, viscosity, and the like. The flow sensor operably connected to the applicator 60 may further detect the dimensions of the nozzle of the applicator 60, such as a gun, glue gun, adhesive gun, and the like. The flow rate information may be received and processed by the controller 100 to execute the control signal.

[0116] The controller 100 may receive substrate information from the substrate sensor 72. The substrate sensor 72 may be configured to detect substrates 62 passing by the support 64, for example, via the conveyor 80. The substrate information may include the number, size, and / or type of substrates 62 and may be used to determine the amount of material 16 to be applied to reach a target adhesive amount per substrate. For example, as more substrates 62 pass by the support 64, more material 16 may need to be applied. Also, larger substrates 62 may require additional portions of material 16. The substrate sensor 72 may be positioned and / or configured to detect the application area of ​​the substrate 62. For example, if the material dispensing system 10 is intended to apply material 16 to a seam of a substrate (such as a box), the substrate sensor 72 may be configured to measure the length of the seam to determine the amount of adhesive material that needs to be applied to the seam. The substrate sensor 72 may generate a signal to the controller 100 indicative of the substrate information.

[0117] The controller 100 may generate control signals to a first actuator 48 and a second actuator 49 associated with the pump 44. The controller 100 may hydraulically, mechanically, magnetically and / or electrically vary the operating state of the first actuator 48 and the second actuator 49, which may control the rate at which the pump 44 pumps the material 16 through the material delivery system 10.

[0118] The controller 100 may be configured to perform machine control, including starting, stopping, controlling, and / or other similar aspects of pumping in the material dispensing system 10. In particular, the controller 100 may receive and / or generate various control information, such as target information regarding a target amount of adhesive per substrate for the control system 11. For example, the adhesive applied per substrate may depend on many aspects of flow information (e.g., flow rate, pressure, temperature, and / or viscosity of the material 16) and substrate information (e.g., amount and dimensions of the substrate 62). Thus, the controller 100 may detect each of these aspects by sensors and determine how these aspects affect the adhesive per substrate 62. The controller 100 may compare the actual flow information to the target amount of adhesive per substrate 62. In response, the controller 100 may send control signals to control the first actuator 48 and the second actuator 49 to operate at pump speeds associated with the target amount of adhesive applied per substrate.

[0119] The controller 100 may be associated with a user interface 24 to provide a user with information regarding and control over the pumping functions of the material dispensing system 10. The user interface 24 may present the user with information regarding adhesive flow rate, motor speed and other pumping related parameters of the material dispensing system 10. The user interface 24 may provide controls for the user to adjust the pumping related parameters of the material dispensing system 10. In some embodiments, the user interface 24 may be configured to receive a target adhesive amount to be applied per substrate 62 or other control information from the user. For example, the user interface 24 may receive a target value of one gram of material 16 to be applied per substrate 62. The user interface 24 may then generate a signal to the controller 100, which is processed to control and / or determine the required rate of material 16 and the corresponding pressure of the pump 44. The controller 100 may take into account the flow rate information (e.g., pressure, temperature, viscosity and / or nozzle dimensions) and substrate information (e.g., speed of the conveyor 80 of the support 64 to determine the exposure of the substrate 62 to the material 16). The controller 100 may then generate control signals to the first actuator 48 and the second actuator 49 to control the pump 44 .

[0120] In addition to receiving measured flow rate information from the flow sensors 59, 61, the controller 100 may be configured to compare the measured flow rate information to control information. In response to this comparison, the controller 100 may generate and execute motor control commands or may control or adjust the first and second actuators, such as by controlling the frequency or voltage of the power supplied to the first and second actuators 48, 49. The pump 44 may then be controlled or adjusted to produce a flow rate of the material 16 (e.g., as measured by one of the flow sensors 59, 61) that corresponds to a target amount of adhesive to be applied per substrate 62 associated with the control command. By continuously measuring the flow rate of the material 16 and continuously adjusting the pump 44 (by the first and second actuators 48, 49) in light of the measured flow rate information, a closed loop adhesive flow rate feedback system is provided.

[0121] Exemplary pumps for the purposes of this disclosure are disclosed in U.S. Pat. No. 7,381,035, issued Feb. 11, 2005, assigned to Nordson Corporation, U.S. Pat. No. 6,155,806, issued Dec. 16, 1998, assigned to Nordson Corporation, and U.S. Pat. No. 5,325,762, issued July 26, 1993, assigned to Nordson Corporation, the disclosures of which are incorporated herein by reference.

[0122] Exemplary components for the present disclosure are disclosed in U.S. Pat. No. 5,054,650, issued Mar. 8, 1990, assigned to Nordson Corporation, U.S. Pat. No. 4,988,15, issued Mar. 8, 1990, assigned to Nordson Corporation, and U.S. Pat. No. 4,987,854, issued Dec. 12, 1988, assigned to Nordson Corporation, the disclosures of which are incorporated herein by reference.

[0123] The following are some non-limiting examples of aspects of the disclosure. Examples include the following: 1. A method of controlling material application in a material discharge system includes implementing a conveyor configured to transport substrates along a discharge line at a speed, implementing an applicator configured to apply a desired amount of material to each of the substrates, implementing a pump configured to deliver material to the applicator under pressure, implementing a controller configured to receive the desired speed of the conveyor and control the speed of the conveyor to transport the substrates along the discharge line at the desired speed, determining by the controller a target pressure of material delivered by the pump to the applicator to deliver the desired amount of material to each of the substrates using a control algorithm, measuring an amount of material applied to a plurality of substrates by the pump, comparing the material applied for each substrate to a target value, and adjusting the pressure of the pump based on comparing the material applied for each substrate to the target value.

[0124] The above embodiment may further include any one or combination of two or more of the following embodiments: 2. A method of controlling material application in a material dispensing system as described in any embodiment herein, wherein the control algorithm is configured to account for a non-linear relationship between the pressure of the material and the speed of the conveyor. 3. A method of controlling material application in a material dispensing system as described in any embodiment herein, wherein the control algorithm is configured to account for a non-linear relationship of flow resistance of components of the material dispensing system for determining the pressure of the material and the speed of the conveyor. 4. A method of controlling material application in a material dispensing system as described in any embodiment herein, wherein the controller uses a non-linear control algorithm to determine a target pressure of material supplied by a pump to an applicator based on a desired speed for supplying a desired amount of material to each of the substrates. 5. A method of controlling material application in a material dispensing system as described in any embodiment herein, wherein the controller receives a desired speed for controlling the speed of the conveyor, and the controller uses a non-linear control algorithm to determine a target pressure of material supplied by a pump to an applicator based on a desired speed for supplying a desired amount of material to each of the substrates. 6. A method of controlling material application in a material dispensing system as described in any of the embodiments herein, comprising generating, by the controller, a control algorithm that provides a desired amount of material to be applied to a substrate by receiving, by the controller and / or user interface, an associated operating pressure of the material for each of a plurality of line speeds of the conveyor during operation of the material dispensing system at a plurality of line speeds. 7. A method of controlling material application in a material dispensing system as described in any of the embodiments herein, comprising storing, by the controller, an association between each of a plurality of line speeds of the conveyor and an associated operating pressure of the material.8. The method of controlling material application in a material dispensing system as described in any embodiment herein, wherein generating a control algorithm by the controller includes generating an algorithm by the controller based on a plurality of line speeds of the conveyor and associated operating pressures of the material to generate a pressure of the material for applying a desired amount of material to the substrate at any speed of the conveyor in a subsequent operation of the material dispensing system. 9. The method of controlling material application in a material dispensing system as described in any embodiment herein, wherein the conveyor is configured to transport the substrate along the discharge line at a variable speed and / or at one of a plurality of speeds. 10. The method of controlling material application in a material dispensing system as described in any embodiment herein, wherein the material is an adhesive.

[0125] Examples include the following: 11. A material dispensing system comprising: a conveyor configured to transport substrates along a discharge line at a speed; an applicator configured to apply a desired amount of material to each of the substrates; a pump configured to deliver material under pressure to the applicator; a controller configured to receive the desired speed of the conveyor and control the speed of the conveyor to transport the substrates along the discharge line at the desired speed; the controller configured to use a control algorithm to determine a target pressure of material delivered by the pump to the applicator to deliver the desired amount of material to each of the substrates; and a flow sensor configured to measure an amount of material applied to a plurality of substrates by the pump, wherein the controller is configured to compare the material applied for each substrate to a target value to generate a comparison value, and the controller is configured to adjust the pressure of the pump based on the comparison value.

[0126] The above embodiment may further include any one or combination of two or more of the following embodiments: 12. The material dispensing system of any embodiment herein, wherein the control algorithm is configured to account for a non-linear relationship between the pressure of the material and the speed of the conveyor. 13. The material dispensing system of any embodiment herein, wherein the control algorithm is configured to account for a non-linear relationship of the flow resistance of the components of the material dispensing system to determine the pressure of the material and the speed of the conveyor. 14. The material dispensing system of any embodiment herein, wherein the controller uses the non-linear control algorithm to determine a target pressure of the material to be supplied by the pump to the application device to supply a desired amount of the material to each of the substrates. 15. The material dispensing system of any embodiment herein, wherein the controller uses the non-linear control algorithm to determine a target pressure of the material to be supplied by the pump to the application device based on the desired speed to supply a desired amount of the material to each of the substrates. 16. The material dispensing system of any embodiment herein, wherein during operation of the material dispensing system at a plurality of line speeds, the controller generates a control algorithm to supply a desired amount of material to be applied to the substrate by receiving, via the controller and / or user interface, an associated operating pressure of the material for each of a plurality of line speeds of the conveyor. 17. The material dispensing system of any of the embodiments herein, wherein each of a plurality of line speeds of the conveyor and an associated operating pressure of the material are associated and stored by the controller. 18. The material dispensing system of any of the embodiments herein, wherein generating a control algorithm by the controller includes generating an algorithm by the controller based on a plurality of line speeds of the conveyor and an associated operating pressure of the material to generate a pressure of the material for applying a desired amount of material to the substrate at any speed of the conveyor in a subsequent operation of the material dispensing system. 19. The material dispensing system of any of the embodiments herein, wherein the conveyor is configured to transport the substrate along the dispensing line at a variable speed and / or at one of a plurality of speeds. 20. The material dispensing system of any of the embodiments herein, wherein the material is an adhesive.

[0127] Computer programs based on the descriptions and methods herein, including the calibration process 500, are within the skill of a software developer. The various programs or program modules, including the calibration process 500, may be created using various programming techniques. For example, the program sections or program modules can be designed in or by Java, C, C++, assembly language or any such programming language. One or more of such software sections or modules may be integrated into a computer system, a non-transitory computer readable medium, or existing communication software. The computer program, including the calibration process 500, may be read and executed by the processor of the controller 100.

[0128] Terms such as first, second, etc. may be used herein to describe various elements, but it will be understood that these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element can be called a second element, and similarly, a second element can be called a first element, without departing from the scope of the present disclosure. As used herein, the term "and / or" includes any and all combinations of one or more associated listed items.

[0129] Relative terms such as "lower" or "upper" or "top" or "lower" or "horizontal" or "vertical" may be used herein to describe the relationship of one element, layer or region to another element, layer or region as shown in the figures. It is understood that these terms, and those discussed above, are intended to encompass different orientations of the device in addition to the orientation shown in the figures.

[0130] The terms used herein are only for describing certain aspects and are not intended to limit the disclosure. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise. Furthermore, as used herein, the terms "comprises," "includes," and / or "having" are used to specify the presence of stated features, integers, steps, operations, elements, and / or components, but are understood not to preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0131] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. It will be further understood that the terms used herein should be interpreted as having a meaning consistent with their meaning in the context of the present specification and related art, and are not to be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0132] The present disclosure may be practiced on any type of computing device, such as, for example, a desktop computer, a personal computer, a laptop / mobile computer, a personal data assistant (PDA), a mobile phone, a tablet computer, a cloud computing device, etc., with wired / wireless communication capabilities over a communication channel.

[0133] Furthermore, in accordance with various aspects of the present disclosure, it is contemplated that the methods described herein are operable with dedicated hardware implementations, including, but not limited to, PCs, PDAs, semiconductors, application specific integrated circuits (ASICs), programmable logic arrays, cloud computing devices and other hardware devices configured to perform the methods described herein.

[0134] It should also be noted that the software implementation of the disclosure described herein is optionally stored on a tangible storage medium, such as a magnetic optical medium, such as a disk, or a magnetic or optical medium, such as a disk, or a solid state medium, such as a memory card, or other package containing one or more read-only (non-volatile) memories, random access memories, or other re-writable (volatile) memories. A digital file attachment to an email or other self-contained information archive or set of archives is considered a distribution medium equivalent to a tangible storage medium. Thus, the disclosure is considered to include tangible storage or distribution media, including those enumerated herein and art-recognized equivalents and successor media, in which the software implementation of the disclosure is stored.

[0135] Moreover, various aspects of the disclosure may be implemented in non-general purpose computer embodiments. Moreover, various aspects of the disclosure described herein improve the functionality of the system as is evident from the disclosure. Moreover, various aspects of the disclosure include computer hardware that is specially programmed to solve the complex problems addressed by the disclosure. Thus, various aspects of the disclosure improve the functionality of the overall system in its particular implementation to perform the processes described by the disclosure and defined by the claims.

[0136] Artificial intelligence and / or machine learning may utilize any number of methods including one or more of cybernetics and brain simulation, symbolic, cognitive simulation, logic-based, anti-logic, knowledge-based, sub-symbolic, embodied intelligence, computational intelligence and soft computing, machine learning and statistics, etc.

[0137] The many features and advantages of the present disclosure will be apparent from the detailed description, and thus, the appended claims are intended to cover all such features and advantages of the present disclosure that fall within the true spirit and scope of the present disclosure. Moreover, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the present disclosure to the exact construction and operation illustrated and described, and therefore, all suitable modifications and equivalents may be resorted to that are within the scope of the present disclosure.

[0138] Additionally, although exemplary embodiments are described herein, the scope includes any embodiment having equivalent elements, modifications, omissions, combinations (e.g., of embodiments across various aspects), adaptations or variations based on this disclosure. Additionally, the steps of the disclosed methods may be modified in any manner, including rearrangement of steps or insertion or deletion of steps.

Claims

1. implementing a conveyor configured to transport the substrate at a velocity along the discharge line; implementing an application device configured to apply a desired amount of material to each of the substrates; implementing a pump configured to deliver the material under pressure to the application device; implementing a controller configured to receive a desired speed of the conveyor and to control the speed of the conveyor to transport the substrate along the discharge line at the desired speed; determining, by the controller, a target pressure for the material to be delivered by the pump to the applicator device to deliver a desired amount of material to each of the substrates using a control algorithm; Metering an amount of material applied to a plurality of substrates by a pump; comparing the material applied to each of the substrates to a target value; adjusting a pressure of the pump based on comparing the material applied to each of the substrates with a target value; A method for controlling application of material in a material dispensing system, comprising:

2. The method of controlling material application in a material dispensing system of claim 1 , wherein the control algorithm is configured to account for a non-linear relationship between the pressure of the material and the speed of the conveyor.

3. The method of controlling material application in a material dispensing system of claim 1 , wherein the control algorithm is configured to take into account a non-linear relationship of flow resistance of components of the material dispensing system for determining the pressure of the material and the speed of the conveyor.

4. 2. The method of controlling material application in a material dispensing system of claim 1, wherein the controller uses a non-linear control algorithm to determine the target pressure of the material supplied by the pump to the application device based on the desired speed for supplying the desired amount of the material to each of the substrates.

5. the controller receives the desired speed for controlling the speed of the conveyor; 2. The method of controlling material application in a material dispensing system of claim 1, wherein the controller uses a non-linear control algorithm to determine the target pressure of the material supplied by the pump to the application device based on the desired speed for supplying the desired amount of the material to each of the substrates.

6. 2. The method of controlling material application in a material dispensing system of claim 1, further comprising: generating, by the controller, the control algorithm that provides a desired amount of the material to be applied to the substrate by receiving, by the controller and / or user interface, an associated operating pressure of the material for each of the multiple line speeds of the conveyor during operation of the material dispensing system at multiple line speeds.

7. 7. The method of claim 6, further comprising storing, by the controller, an association between each of the plurality of line speeds of the conveyor and the associated operating pressure of the material.

8. 8. The method of controlling material application in a material dispensing system of claim 7, wherein generating the control algorithm by the controller includes generating an algorithm by the controller based on the multiple line speeds of the conveyor and the associated operating pressures of the material to generate a pressure of the material for applying the desired amount of the material to the substrate at any speed of the conveyor during subsequent operation of the material dispensing system.

9. The method of claim 1 , wherein the conveyor is configured to transport the substrate along the discharge line at a variable speed and / or at one of a plurality of speeds.

10. The method of claim 1 , wherein the material is an adhesive.

11. a conveyor configured to transport the substrate at a velocity along the discharge line; an application device configured to apply a desired amount of material to each of said substrates; a pump configured to deliver the material under pressure to the application device; a controller configured to receive a desired speed of the conveyor and to control the speed of the conveyor to transport the substrate along the discharge line at the desired speed; the controller is configured to use a control algorithm to determine a target pressure of the material delivered by the pump to the application device to deliver the desired amount of the material to each of the substrates; a flow sensor configured to measure an amount of material applied to the plurality of substrates by the pump; 1. A material dispensing system comprising: the controller is configured to compare the material applied to each of the substrates with a target value to generate a comparison value; The controller is configured to adjust the pressure of the pump based on the comparison value.

12. The material dispensing system of claim 11 , wherein the control algorithm is configured to account for a non-linear relationship between the pressure of the material and the speed of the conveyor.

13. The material dispensing system of claim 11 , wherein the control algorithm is configured to account for non-linear relationships of flow resistances of components of the material dispensing system for determining the pressure of the material and the speed of the conveyor.

14. 12. The material dispensing system of claim 11, wherein the controller uses a non-linear control algorithm to determine the target pressure of the material supplied by the pump to the application device to deliver the desired amount of the material to each of the substrates.

15. 12. The material dispensing system of claim 11, wherein the controller uses a non-linear control algorithm to determine the target pressure of the material supplied by the pump to the application device based on the desired speed to supply the desired amount of the material to each of the substrates.

16. The material dispensing system of claim 11, further comprising: generating, by the controller, the control algorithm that provides a desired amount of the material to be applied to the substrate by receiving, by the controller and / or user interface, an associated operating pressure of the material for each of the multiple line speeds of the conveyor during operation of the material dispensing system at the multiple line speeds.

17. 17. The material dispensing system of claim 16, further comprising storing, by the controller, in association each of the plurality of line speeds of the conveyor and the associated operating pressure of the material.

18. 20. The material dispensing system of claim 17, wherein generating the control algorithm by the controller comprises generating an algorithm by the controller based on the multiple line speeds of the conveyor and the associated operating pressures of the material to generate a pressure of the material for applying the desired amount of the material to the substrate at any speed of the conveyor during subsequent operation of the material dispensing system.

19. The material dispensing system of claim 11 , wherein the conveyor is configured to transport the substrate along the dispensing line at a variable speed and / or at one of a plurality of speeds.

20. The material dispensing system of claim 11 , wherein the material is an adhesive.

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