Dosing system and method to control the dosing system

Abstract

The present invention relates to a dosing system (1) for dosing a dosing material. The dosing system (1) comprises a housing (11) including a nozzle (70) and a supply channel (62) for dosing material, a discharge element (80) movably mounted in the housing (11), and an actuator unit (10) coupled to the discharge element. The actuator unit (10) comprises an actuator (12) having a membrane (13) that can be pressurized by a pressure medium to move the discharge element (80) in a discharge direction (RA). The discharge element (80) is formed separately from the membrane and is pressurized by a force acting on the discharge element (80) to a surface (19) of the membrane (13) facing the discharge element (80) in order to be coupled to the actuator unit (10). The present invention also relates to a method for controlling the dosing system (1).

Description

Technology Field

[0001] The present invention preferably relates to a dosing system for dosing a liquid to viscous dosing material to apply a dosing material to a substrate, and a method for controlling the dosing system. Background Technology

[0002] The aforementioned type of dosing system is used in various applications to dose a dosed medium, typically a liquid or viscous dosing material, in a targeted manner. In the context of so-called "microdosing technology," it is often necessary to deliver a very small amount of medium to a target surface with high accuracy—that is, at the right time, in the right place, and with an accurate dosing amount.

[0003] Dosing is often performed non-contactually, that is, without direct contact, between the dosing system and the target surface. This can be accomplished, for example, by delivering the dosing material to a droplet through the nozzle of the dosing system. In this case, the medium comes into contact only with the internal space of the nozzle, and in most cases, only with the area of ​​the discharge element of the dosing system. The size of the droplet or the amount of medium per droplet can be predicted as accurately as possible by the structure and control of the nozzle and the targeting effect achieved thereby. This non-contact method is often referred to as the "jet method." Common examples of this include injecting adhesive dots, solder paste, etc., when assembling circuit boards or other electronic components, or applying converter materials for LEDs.

[0004] A movable discharge element may be arranged in the nozzle of a dosing system to deliver a medium from the dosing system. The discharge element is pushed forward inside the nozzle at a relatively high speed toward the nozzle opening or outlet opening to discharge a drop of the medium, and then retracts. This means that in the previously mentioned dosing system and the dosing system according to the present invention, the dosing material is discharged from the nozzle by the discharge element itself. For discharge from the nozzle, the discharge element contacts the dosing material to be discharged and "pressurizes" or "pushes" the dosing material out of the nozzle of the dosing system due to the movement of the discharge element and / or the nozzle. Thus, the dosing material is effectively "actively" discharged from the nozzle by the movable discharge element. Therefore, this type of dosing system and the dosing system according to the present invention differ from other dispenser systems in which the nozzle is opened solely by the movement of a closing element and the pressurized dosing material exits the nozzle on its own. This corresponds, for example, to the injection valve of an internal combustion engine.

[0005] Typically, the discharge element can also move from the nozzle to a closed position where it is firmly connected to the sealing sheet of the nozzle opening and temporarily held there. When using a higher viscosity dosing material, the discharge element may be sufficiently held in a simply retracted position, that is, a position away from the sealing sheet, without any drop of the medium escaping.

[0006] The movement of the discharge element required to discharge the dosing material generally occurs with the assistance of the actuator unit of the dosing system. In principle, such actuator units can be realized in various ways, for example, by pneumatic or hydraulic actuators. Alternatively, piezoelectric and / or electromagnetic actuators are used. Compared to the aforementioned actuator principles, actuator units equipped with pneumatic or hydraulic actuators also feature a relatively simple structure that reduces the overall complexity of the dosing system. Therefore, pneumatic or hydraulic actuators represent a cost-effective solution for operating the dosing system, particularly for handling dosing materials that are easy to dose.

[0007] Pneumatic or hydraulic actuators can be implemented in various ways. For example, dosing systems are known in which the actuator is realized by a pneumatic or hydraulic cylinder. In such systems, because a relatively high level of wear occurs in the friction seal area of ​​the cylinder, pneumatic or hydraulic actuators realized by bellows that can be pressurized by a pressure medium are increasingly being used.

[0008] Another desirable alternative is to form a pneumatic or hydraulic actuator using a membrane that can be pressurized by a pressure medium. This variant has the advantage, on the one hand, of being able to omit friction seals such as those found in pneumatic or hydraulic cylinders. On the other hand, it can reduce design and manufacturing effort compared to "bellows-actuated" actuators. More advantageous "membrane-actuated" pneumatic or hydraulic actuators can typically operate at higher clock frequencies than "bellows-actuated" or "cylinder-actuated" actuators. Therefore, "membrane-actuated" pneumatic or hydraulic actuators are particularly suitable for extremely precise dosing requirements.

[0009] To transmit the force generated by a “membrane-actuated” pneumatic or hydraulic actuator to the discharge element of a dosing system, the deflectable membrane of the actuator is firmly connected to the discharge element of the dosing system in a known dosing system. For example, the discharge element may be permanently welded, riveted, screwed, soldered, or bonded to the membrane. Likewise, the discharge element may completely penetrate the membrane and be firmly screwed to the membrane at at least one surface of the membrane, or be firmly connected to the membrane through a retaining ring or pin. A fixed connection between the discharge element and the membrane can actually be achieved by the aforementioned methods.

[0010] However, on the other hand, this structure also increases the total mass of the membrane to be moved due to the necessary connecting mechanisms. To still deflect or move the membrane in the desired manner, the diameter of the membrane may be increased to increase the acceleration of the membrane. However, increasing the membrane diameter also increases the volume of the actuator chamber of the pneumatic or hydraulic actuator, into which the pressure medium is filled to deflect the membrane. However, this design requires more time for the process of filling or emptying the actuator chamber, and the clock frequency of the dosing system becomes unnecessarily slow.

[0011] On the other hand, in conventional pneumatic or hydraulic actuators, the membrane can be significantly weakened due to the discharge element being fixedly connected to the membrane. In particular, the connection point between the discharge element and the membrane can form a weakness in the membrane in a predetermined breaking point manner, which can be a problem, especially in the continuous operation of the dosing system. As a result, the service life or effective life of the pneumatic actuator can be significantly shortened, which may lead to higher maintenance efforts and consequently higher operating costs for the dosing system. The problem to be solved

[0012] Accordingly, the object of the present invention is to provide a dosing system having an actuator that can reduce and preferably avoid the aforementioned disadvantages. Additionally, the object of the present invention is to provide a method for controlling such a dosing system. means of solving the problem

[0013] The present objective is achieved by a dosing system according to patent claim 1, and a method for controlling such a dosing system according to patent claim 13.

[0014] Particularly preferably, a dosing system according to the present invention for dosing a liquid or viscous dosing material to apply a dosing material to a substrate non-contactually comprises a multi-component housing, wherein the housing comprises at least one nozzle and a supply channel for the dosing material. The dosing material to be dosed is delivered to the nozzle chamber of the nozzle through the supply channel of the dosing system.

[0015] The dosing system further comprises a discharge element movably arranged within a housing, and an actuator unit coupled to or interacting with the discharge element to dispense a dosing material. As a result of this coupling, the actuator unit interacts with the discharge element in such a manner that the dosing material is dispensed from the nozzle of the dosing system by the discharge element. As described above in the introductory part of this application, such a discharge element "actively" discharges the dosing material. Preferably, the dosing system may be realized in a jet valve manner, wherein the dispensing of the dosing material may be performed non-contactually as described above.

[0016] According to the present invention, the actuator unit comprises at least one actuator having a membrane preferably formed in a disc shape, which may also be referred to as an "actuating membrane" as described below. The actuator particularly preferably comprises only a single membrane.

[0017] The actuator unit may further include additional components necessary to move the discharge element in the dosing system as described below. Alternatively, preferably, the component of the dosing system in contact with the dosing material, e.g., the discharge element, is included in the fluid unit of the dosing system as described below.

[0018] The membrane of the actuator, particularly the surface of the membrane facing away from the discharge element, may be pressurized by at least one pressure medium so that the discharge element may be moved or deflected from the nozzle in the discharge direction of the discharge element to discharge the dosing material. When the membrane is pressurized, the moving pressure medium, in particular, directly strikes or hits the surface of the membrane facing away from the discharge element (upper side), as indicated by the name "pressurized." This means that the membrane is directly deflected by the pressure medium itself to discharge the dosing material from the nozzle. To this end, the discharge element is moved by the membrane in the direction of the outlet opening of the nozzle. The movement may be performed such that the tip of the discharge element comes into direct contact with the sealing sheet of the nozzle upon completion of the discharge movement. Alternatively, the discharge movement may also be stopped in advance with a distance between the tip of the discharge element and the sealing sheet of the nozzle.

[0019] According to the present invention, the discharge element is formed separately from the membrane, that is, the discharge element is a component separate from the membrane itself. The discharge element is particularly preferably formed as a single member. To be coupled to an actuator unit, the discharge element is placed in an operating position by being pressurized by a contact pressure applied to the surface of the membrane facing the discharge element, by a force acting directly on the discharge element during the operation of the dosing system. Thus, the surface of the membrane provided for coupling faces opposite to the surface of the membrane that can be pressurized by the pressure medium. The two surfaces of the membrane correspond to the base surface of the membrane in terms of design, as will be described later.

[0020] When the dosing system is used as intended (i.e., because the dosing system is typically arranged so that the dosing material is discharged downward from the nozzle during use), the surface of the membrane facing the discharge element or nozzle is typically facing "downward," and accordingly, is referred to as the "lower side" of the membrane below, but the present invention is not limited thereto. Accordingly, the surface opposite to the lower side of the membrane, which can be pressurized by a pressure medium, is referred to as the "upper side" of the membrane.

[0021] For example, for coupling between a discharge element such as a plunger and an actuator unit, the force is applied only to the discharge element itself, and accordingly, is not applied directly to the membrane itself but is applied indirectly to the membrane only through the discharge element, that is, due to coupling, at least a portion of the force can be transferred from the discharge element to the membrane.

[0022] According to the present invention, as mentioned, the discharge element is formed separately from the membrane, that is, the discharge element is not fixedly or permanently connected to the membrane. In particular, no forced connection or material connection is required between the components to bond the discharge element to the actuator unit or the membrane of the actuator. Rather, bonding occurs according to the principle of adhesion. Due to the force acting on the discharge element, the discharge element can be maintained in a state of continuous, operably contact with the surface of the membrane facing the discharge element during the operation of the dosing system. The discharge element and the membrane re-form two separate, independent components only when the force acting on the discharge element for bonding is eliminated or falls below a certain value.

[0023] Therefore, retaining the discharge element in the membrane occurs particularly "without penetration" and "without damage." This means that the discharge element is not attached to the membrane, for example, by screwing, welding, or bonding. In particular, there is no substantial change in the surface condition of the lower and / or upper sides of the membrane for the bonding.

[0024] Since the discharge element and the membrane are formed as independent and unconnected components and are coupled to the functional unit (dosing system) only by the force acting on the discharge element, it is advantageously possible for the actuator of the actuator unit to move only a very small mass during the operation of the dosing system according to the present invention. Thus, on the one hand, the total weight of the operating membrane can be kept as low as possible, and on the other hand, the volume of the actuator chamber for operating the membrane can be kept small. This design can accelerate the process of the actuator filling and emptying the actuator chamber, thereby achieving very high dynamic values. Advantageously, the dosing system is suitable for dosing high-viscosity dosing materials despite its relatively simple design.

[0025] More advantageously, in the dosing system according to the present invention, weakening of the membrane material in relation to the design can be almost completely avoided in the fixed connection area between the membrane and the discharge element, as in the case of conventional dosing systems. In addition, friction seals, such as those required in pneumatic or hydraulic cylinders, can be omitted in the actuator. Thus, advantageously, the uninterrupted service life of the actuator and thus the entire dosing system can be extended by the dosing system according to the present invention, and at the same time, a very high clock frequency is possible when dispensing the dosing material.

[0026] Particularly preferably, in a method according to the present invention for controlling a dosing system for dosing a liquid or viscous dosing material to apply a dosing material to a substrate non-contactually, the dosing system optionally has a multi-component housing, wherein the housing includes at least one nozzle and a supply channel for the dosing material. As described above, the housing includes a discharge element movably arranged within the housing, and an actuator unit coupled to or interacting with the discharge element to dispense the dosing material.

[0027] According to the present invention, the (operating) membrane of the actuator of the actuator unit is pressurized by a pressure medium to move or deflect the discharge element in the discharge direction of the discharge element to discharge a dosing material from the nozzle. Preferably, the surface of the membrane facing away from the discharge element (also referred to as the “upper side”) is pressurized by the pressure medium to move the discharge element toward the nozzle. A force is applied to the discharge element itself to be coupled to the actuator unit. Due to the force acting on the discharge element, the discharge element is pressurized or pressured by contact pressure on the surface of the membrane facing the discharge element (also referred to as the “lower side”). A force may be applied to the discharge element so as to maintain continuous operable contact with the membrane, particularly with the surface of the membrane facing the discharge element, during the operation of the dosing system.

[0028] Furthermore, particularly advantageous embodiments and modifications of the present invention are apparent from the dependent claims and the description below, wherein independent claims of a claim category may also be further improved in a manner similar to dependent claims and embodiments of other claim categories, and in particular, individual features of different embodiments or modifications may also be combined into a new embodiment or modification.

[0029] Preferably, the dosing system is formed such that the force in the ejection direction, i.e., the direction of ejection movement, acting on the ejection element, e.g., the plunger, for coupling is directed toward the opposite side of the ejection element. The ejection direction corresponds to the (linear) movement of the ejection element for dispensing the dosing material from the nozzle. Thus, the ejection direction starts from the point of coupling (between the ejection element and the membrane) and is directed toward the nozzle of the dosing system. Therefore, preferably, the force can be applied to the ejection element for coupling in such a way that the (movement) direction of the force is directed toward the opposite side of the nozzle and is aligned substantially perpendicularly to the base surface of the membrane of the actuator.

[0030] The movement of the discharge element in the opposite direction, also known as a "plunger" by synonym, that is, the movement opposite to the nozzle, is called retraction. Therefore, retraction is the retraction direction of the discharge element, as explained below.

[0031] Particularly preferably, the dosing system may be formed such that the discharge element is permanently pressurized toward the lower side of the membrane during operation to be coupled to the actuator unit by a force applied by at least one spring and / or pressure device. In particular, the force applied by the spring and / or pressure device is sufficiently large to maintain continuous direct contact with the lower side of the membrane even during the retraction movement of the discharge element, that is, when the discharge element moves again from the nozzle toward the actuator unit after the dosing material has been discharged.

[0032] A spring and / or pressure device may simply be a spring device composed of a plurality of springs or other spring-equipped components. In the simplest and often preferred case, it may be composed of a single spring-equipped component, such as a coil spring. Hereinafter, (without limiting generality) a spring device is also referred to as a spring or "return spring" for simplicity. Alternatively or additionally, the spring and / or pressure device may also have other forms of pressurizing elements, such as pneumatic cylinders, other membrane devices, etc.

[0033] Preferably, the return spring may be formed to move the discharge element to a resting position within a specific time interval, particularly as soon as the membrane is no longer pressurized by the pressure medium. The resting position of the discharge element is characterized by the distance between the tip of the discharge element and the nozzle (during operation) reaching the maximum possible distance, i.e., the discharge element being pushed as far upward as possible toward the actuator unit by the spring. Preferably, the discharge element also comes into direct contact with the lower side of the membrane even in the resting position.

[0034] Additionally, the return spring can preferably also apply a "reset effect" to the membrane. The membrane can actually preferably be formed so that it automatically returns to a resting position within a certain time interval as soon as the membrane is no longer pressurized by the pressure medium, that is, so that the membrane can be formed elastically. However, the force applied by the return spring can at least support the elastic properties of the membrane, that is, the spring can facilitate the membrane returning to the resting position.

[0035] Preferably, the return spring may be formed to transmit a force to the membrane (indirectly by the discharge element), wherein the force preferably acts in the direction of the actuator unit away from the nozzle, and preferably the return spring may be determined to push / pull the membrane upward by a specific amount (indirectly) or return the membrane to a resting position. The resting position of the membrane exists when the membrane is not currently pressurized by the pressure medium and / or is not deflected toward the nozzle. In the resting position, the membrane or membrane wall may preferably extend substantially in a single plane, that is, have a profile in which the cross-section is substantially straight or linear. However, it is also possible for the membrane to be curved at least partially "upward" in the resting position, that is, to be curved toward the actuator unit, and, for example, for the membrane to be pushed upward by the discharge element.

[0036] Preferably, a force may also be applied to the discharge element to be coupled as described so that the discharge element actually contacts the lower side of the membrane in the resting position, while the cross-section of the membrane substantially maintains the aforementioned linear profile. However, alternatively, the spring may also be dimensioned and / or designed so that the discharge element pushes or deflects the membrane upward by a specific amount in the direction of the actuator unit (in the resting position). Preferably, in the resting position, the membrane may contact the base body of the actuator at least partially.

[0037] The membrane of the actuator may preferably be formed in a disc shape. In this case, the disc is generally understood to mean a geometric body or structure in which the base surface is several times larger than its thickness. The base surface corresponds to the region of the membrane having the largest area scale. Thus, the base surface corresponds, on the one hand, to the surface of the membrane facing the plunger, and on the other hand, to the (opposite) surface of the membrane that can be pressurized by the pressure medium.

[0038] The thickness of the membrane corresponds to an extension of the membrane orthogonal to the base surface, where the thickness is taken, for example, as a cross-section (transverse plane) traversing the base surface. Preferably, the membrane may have a constant, uniform thickness over its entire length. However, the edge region of the membrane (in the transverse plane) may be thinner than the middle region of the membrane. Thus, the stiffness of the membrane may be increased, for example, in the central region where the discharge element of the membrane contacts, where the membrane is deflected mainly in the edge region when pressurized by a pressure medium. As a result, the effective area of ​​the membrane and the force generated by the membrane may be increased. Alternatively or additionally, the membrane may have a bead in the edge region, as in the case of a speaker, for example.

[0039] In addition, the membrane can be conceived with a corrugated cross section, such as a corrugated sheet, where the spring rate of the membrane and consequently the restoring force are reduced compared to a "non-corrugated" or flat membrane. For simplicity, and without limitation, the starting point is a flat membrane of uniform thickness having a profile in which the cross section at the resting position is mostly straight.

[0040] Regardless of the specific composition of the membrane, the thickness of the membrane may be at least 10 µm, preferably at least 50 µm, and preferably at least 150 µm. The maximum thickness of the membrane may be up to 1000 µm, preferably up to 300 µm, and preferably up to 200 µm.

[0041] Preferably, the base surface of the membrane may be formed substantially circular or circular. However, in principle, it may also be formed elliptical, rectangular, or any other shape. It is preferable that the membrane be formed as a flat or thin, and thus "plate-like" structure. Particularly preferably, the membrane is formed without cavities; that is, cavities such as liquid filling and / or gas filling chambers are not located within the membrane. Thus, the membrane differs significantly from bellows, such as metal bellows. Unlike the membrane, the bellows comprises a more or less elastic hose that folds together "like an accordion," and an internal space sealed against the environment, for example, a cavity filled with gas.

[0042] The membrane is preferably formed entirely of metal. Preferably, the membrane may comprise a mixture of different metals or alloys. For example, the membrane may be formed of stainless steel (spring steel). Alternatively, for example, the membrane may comprise a copper-beryllium alloy. Furthermore, the material of the membrane may be considered to be an elastomer or plastic. Additionally, depending on the requirements, it may be considered to use a multilayer membrane and make individual layers of the same or different materials. For example, the membrane may have a special coating on the upper and / or lower sides. Preferably, the membrane may be made to have high seismic resistance and a specific modulus of elasticity to enable the desired deflection of the membrane. Preferably, the membrane is made to exhibit an "active" expansion element relative to the rigid base body of the actuator, as described below.

[0043] Preferably, the membrane, particularly the edge region of the membrane, is joined to the base body of the actuator's rigidity, possibly of multiple parts, in a sealed manner around the entire perimeter. An actuator chamber of the actuator, which can be pressurized by a pressure medium, is formed between the actuator base body and the membrane, particularly the upper side. For example, the membrane may be welded or soldered to the body to form the actuator chamber. Furthermore, the membrane may also be fitted into the actuator base body, and, for example, the membrane may be clamped and sealed between two housing parts of the actuator base body.

[0044] Accordingly, the actuator chamber is located within the actuator itself. Preferably, the actuator chamber may be formed to be gas-tight and / or liquid-tight with respect to the environment of the actuator. Preferably, the actuator base body includes a penetration (hereinafter referred to as a “bore” without limitation of generality) on the opposite side of the membrane, and this penetration extends from the actuator chamber to the outside of the actuator chamber to enable operation of the actuator. Preferably, a control valve of the actuator unit is immediately adjacent to the bore and controls the flow of a pressure medium through the bore to “open” and “close” the actuator chamber as described below.

[0045] Advantageously, the actuator is realized by a single membrane, in which case only this sealed membrane needs to be coupled to the actuator base body. This allows for the configuration of the dosing system to be simplified, particularly compared to a "bellows-actuated" system. In the latter case, the bellows or hose typically needs to be sealed at two opposing ends.

[0046] For example, a pressure medium can be supplied through the aforementioned bore to control the actuator and the actuator chamber. Preferably, overpressure can be generated in the actuator chamber to deflect the membrane "downward," that is, in the direction of the nozzle of the dosing system, starting from the resting position. The amount of overpressure can be specified and may act according to, for example, the characteristics of the dosing material (e.g., viscosity). For example, the overpressure may be in the range of about 5 bar to 8 bar. However, much higher pressures are also possible, as will be described later. The membrane may also be referred to as a pressure membrane, where the membrane is formed to transmit force to the plunger and simultaneously seal the actuator chamber. Additionally, the actuator chamber can be emptied again through the same bore, that is, the overpressure in the actuator chamber is reduced, in which case the membrane is preferably returned to the vertical resting position by means of an elastic and / or return spring.

[0047] In principle, the actuator chamber can be filled with any flow fluid; that is, (compressed) gaseous and / or liquid substances can be used as the pressure medium. Preferably, a compressed gaseous fluid, for example, a single gas or a mixture of gases, for example, air, can be used as the pressure medium. Hereinafter, it is assumed that the actuator operates using compressed room air, as air is available in most systems that already have a dosing system. Accordingly, the actuator is also referred to as a pneumatic actuator by way of synonym in the context of application. However, the present invention is not limited thereto.

[0048] To control the actuator in an optimal manner for dispensing the dosing material, preferably, as directly mentioned, the aforementioned bore of the actuator chamber is adjacent to the control valve of the actuator unit in a particularly gas and / or liquid hermetic manner. The control valve is preferably formed to control and / or regulate the supply of the pressure medium to the actuator chamber and the discharge of the pressure medium from the actuator chamber. To this end, the control valve is preferably coupled to the control and / or regulation unit of the dosing system. The control valve may be realized, for example, by a solenoid valve. Preferably, the control valve may be realized by a 3 / 2-way valve (e.g., a resting position in the open state). Alternatively, the control valve may comprise, for example, two 2 / 2-way valves. The control valve is also referred to as a pneumatic valve.

[0049] Preferably, the control valve may be arranged in the actuator unit such that a first connection (operating connection) of the control valve (gas-tight) interacts with the bore of the actuator chamber, in which case the actuator chamber may be filled with a pressure medium by this connection and then emptied again. Preferably, a second connection (compressed air connection) of the control valve is functionally coupled to a compressed air supply source of the dosing system. A third connection (exhaust connection) of the control valve may be coupled to the exhaust area of ​​the actuator unit as described later. Depending on the control of the control valve, the operating connection may preferably interact with the compressed air connection or the exhaust connection.

[0050] To supply a sufficient amount of pressure medium to the actuator chamber by means of a control valve during operation, the housing of the dosing system may include an internal pressure reservoir or pressure tank for the pressurized pressure medium.

[0051] Preferably, this pressure tank may be formed confined or isolated within the housing of the dosing system relative to other housing regions. The pressure tank may include at least one supply opening for supplying a pressure medium to the pressure tank, and a discharge opening for discharging the pressure medium from the pressure tank, in particular a supply line to a control valve. Preferably, the pressure tank may be dimensioned to contain a sufficient amount of pressure medium to deflect the membrane at least 250 times, preferably at least 2,000 times, and particularly preferably at least 10,000 times. Preferably, the pressure of the pressure medium within the pressure reservoir may be at least 2 bar, preferably at least 3 bar, and particularly preferably at least 5 bar. Preferably, the pressure is up to 1,000 bar, more preferably up to 20 bar, and most preferably up to 10 bar.

[0052] The pressure tank can be connected to an external compressed air supply source of the dosing system. For example, the compressed pressure medium can be supplied to the pressure reservoir through a supply opening, for instance, where the external pressure medium supply source is connected to a corresponding connection point in the housing of the dosing system. Preferably, a predetermined pressure (target pressure) can be maintained substantially constant in the pressure tank, even during the operation of the dosing system.

[0053] To operate the pneumatic actuator most efficiently, the pressure reservoir can be located inside the housing immediately adjacent to the control valve of the actuator unit. Preferably, the pressure reservoir is arranged within the housing of the dosing system so that the pressure medium can flow directly from the pressure tank to the actuator chamber via the shortest possible path. In other words, the pressure reservoir can be positioned as close as possible to the "required point." Preferably, the discharge opening of the pressure tank is directly connected (gas-tight) to the compressed air connection of the control valve.

[0054] Advantageously, the pressure reservoir represents a "pressure medium buffer" within the dosing system to dampen pulse consumption of the pressure medium, particularly at high dosing frequencies. Typically, a dosing system with a pneumatic actuator has an external pressure tank for this purpose. However, because the pressure of the pressure medium may drop from the external pressure tank to the actuator due to line losses, the actuator chamber is not filled to the desired pressure, particularly a constant pressure. Furthermore, the pressure filling the actuator, also known as the actuator filling pressure, can have a adverse effect on the dosing system by significantly affecting the dosing accuracy of the dosing system, as will be explained later.

[0055] In contrast, in the described dosing system, the "pressure medium buffer" is positioned right next to the actuator, eliminating the need for a line between the pressure tank and the actuator chamber. This ensures that the actuator chamber is always filled with a pressure medium having a specific target pressure, even at very high clock frequencies. Meanwhile, this has the aforementioned positive effect on dosing accuracy.

[0056] On the other hand, since no line loss occurs between the pressure tank and the pneumatic actuator even at very high clock frequencies, this design allows for the achievement of much higher clock frequencies than conventional dosing systems with pneumatic actuators. While a maximum dosing frequency of approximately 330 Hz has been possible so far, the structure described herein enables dosing frequencies of 600 Hz or higher. Essentially, the internal "pressure medium buffer" also allows for much higher clock frequencies (> 700 Hz), and in this respect, the control valve represents a speed-limiting element due to heat generation.

[0057] It should be noted that a configuration in which a pressure reservoir inside the housing is located immediately near the actuator is not limited to the above-mentioned dosing system according to the present invention. Rather, this advantageous configuration represents an independent partial aspect of the present invention.

[0058] Therefore, advantageously, the internal pressure reservoir may be arranged in a dosing system having a pneumatic cylinder or in a conventional "bellows-actuated" or "membrane-actuated" dosing system, that is, also arranged, for example, in a dosing system in which a discharge element is fixedly connected to the membrane of a pneumatic actuator, i.e., independently of the coupling according to the present invention. Preferably, the dosing system may include a housing comprising a nozzle and a supply channel for dosing material, a discharge element movably mounted in the housing, and an actuator unit coupled to the discharge element. The actuator unit may include an actuator having a membrane that can be pressurized by a pressure medium to move the discharge element in the discharge direction. Additionally, the housing of the dosing system may include an internal pressure reservoir for the pressure medium. Particularly preferably, the reservoir may be immediately adjacent to a control valve of the actuator unit for controlling the actuator.

[0059] Therefore, advantageously, (for the reasons explained above) it is possible to achieve the highest possible dosing accuracy even in conventional dosing systems while simultaneously increasing the cycle frequency for dispensing the dosing material.

[0060] To further enhance the beneficial effects of the internal "pressure medium buffer," the dosing system may preferably include, in addition to the internal pressure tank, an additional external pressure tank that may be larger, for example, for the external pressure medium supply source.

[0061] The concept of an internal pressure tank can be advantageously complemented by arranging at least one pressure sensor in the pressure reservoir in a manner that measures the pressure of the pressure medium in the pressure reservoir. For example, the pressure sensor can be realized on the wall of the pressure tank.

[0062] Preferably, the pressure sensor is positioned as close as possible to the pneumatic actuator. The pressure sensor may preferably be coupled to transmit measurement data to the control and / or adjustment unit of the dosing system. On the one hand, the control and / or adjustment unit may be formed as a direct component of the dosing system, or on the other hand, it may be realized separately from the dosing system. A third possibility is to form the control and / or adjustment unit separately and assign it to multiple dosing systems simultaneously to control them independently of each other.

[0063] The term "control" is used hereinafter as a synonym for control and / or regulation. That is, even when discussing controllers, a controller may include at least one regulation process. In closed-loop control (regulation), the variable being regulated (as an actual value) is typically recorded continuously and compared to a reference variable (as a target value). Typically, regulation is performed by adjusting the regulated variable to the reference variable. This implies that the regulated variable (actual value) continuously influences the operation path of the control loop.

[0064] To control the pressure of a pressure reservoir, the dosing system may include at least one controllable pressure regulator. Preferably, the pressure regulator is configured to control and / or regulate the pressure of a pressure medium within a pressure reservoir as a function of an input parameter, preferably by controlling and / or regulating the pressure of a pressure medium flowing into the housing or reservoir of the dosing system.

[0065] The pressure in the pressure reservoir, and thus the pressure applied before the control valve, is also referred to as the actuator's supply pressure. The supply pressure determines the maximum pressure that can fill the actuator chamber, that is, the maximum pressure the pressure medium can have when it flows into the actuator chamber. In the simplest case, the supply pressure may correspond to the actuator filling pressure. The actuator filling pressure corresponds to the pressure that the pressure medium actually has within the (filled) actuator chamber, for example, during the deflection of the membrane. Depending on the configuration of the dosing system, the actuator filling pressure may deviate from the supply pressure, as described later. Therefore, the pressure regulator may preferably also be configured to control and / or regulate the pressure that fills the actuator with the pressure medium (actuator filling pressure) as a function of input parameters.

[0066] The pressure regulator can be operated mechanically or manually. Preferably, input parameters can be transmitted to an operator of the dosing system, in which case the operator adjusts the pressure regulator to ensure that the target pressure reaches the pressure reservoir.

[0067] Preferably, an electronic pressure regulator may also be used. Particularly preferably, the pressure regulator may be controlled by the control and / or regulating unit of the dosing system, particularly with respect to input parameters. Regardless of the specific configuration (mechanical and / or electronic), the pressure regulator may preferably be positioned in the housing of the dosing system and / or in the external pressure medium supply line.

[0068] Preferably, the (mechanical or electronic) pressure regulator can be controlled or regulated as a function of input parameters to achieve a specific speed of the discharge element, e.g., a constant speed (plunger speed), during discharge movement in the operation of the dosing system.

[0069] The input parameter for control or regulation may be, for example, the current pressure of a pressure reservoir. Preferably, as an input parameter (actual value), the measurement data from a pressure sensor may be continuously compared with a target value that can be predetermined by the control and / or regulation unit during operation. Subsequently, preferably, control of the pressure regulator occurs so that the target pressure is continuously maintained in the internal pressure tank or a constant plunger speed is achieved during operation.

[0070] Advantageously, the dosing accuracy of the dosing system can be further improved by a pressure sensor and an internal pressure reservoir interacting with the control and / or adjustment unit. A critical factor regarding the amount of dosing material discharged per plunger stroke is the plunger speed, particularly when impacting the nozzle or sealing sheet. Therefore, preferably, the plunger speed (during the discharge movement) can be adjusted for an operating target value. The plunger speed depends significantly on the actuator filling pressure.

[0071] In this regard, the higher the actuator charging pressure, the higher the acceleration of the membrane, causing the plunger speed to increase. Conversely, if the actuator charging pressure is low, the plunger speed decreases during the discharge process. Therefore, pressure fluctuations during the charging process of the actuator chamber can have a detrimental effect on dosing accuracy. Advantageously, by controlling and / or regulating the pressure of the pressure tank and / or the actuator charging pressure, the plunger speed can be set to a predetermined value and maintained constant, for example, to increase dosing accuracy even under highly dynamic or high dosing requirements. For example, pressure fluctuations in the supply line can be compensated for through this control or regulation.

[0072] To further improve dosing accuracy, the dosing system may include at least one sensor for measuring the movement speed of the discharge element. Preferably, the speed sensor may be arranged in an area of ​​the rigid actuator base body. Preferably, the sensor may be arranged in an area of ​​the actuator base body facing the upper side of the membrane, i.e., "above" the membrane. Preferably, the speed sensor and the discharge element, for example, a plunger head, may be arranged in a virtual (vertical) line. Preferably, the speed sensor is coupled to a control unit.

[0073] The speed sensor is preferably formed to detect the speed of the discharge element during the entire discharge movement and / or entire retraction movement of the discharge element. For example, the speed sensor may be realized by a position sensor (stroke sensor) formed to detect the plunger position as a function of time. Preferably, the speed sensor may be realized by a Hall sensor. Preferably, the "head area" of the discharge element in contact with the membrane may include a magnet.

[0074] Alternatively, the speed sensor may include a capacitive distance sensor. For example, the distance sensor and the membrane (as a movable coupling surface) may form an electric capacitor, for example, in which the membrane is formed in a capacitor plate manner.

[0075] Advantageously, the measured value of the speed sensor can be supplied to the control unit as an additional input parameter. Alternatively or in addition to the measured value of the pressure sensor, the speed measurement can be used to control and / or regulate the actuator's supply pressure and / or actuator charge pressure to achieve a constant plunger speed, for example, particularly when striking the nozzle's sealing sheet during operation. For example, variations in the properties of the dosing material can be compensated for through this control or regulation.

[0076] Another alternative or additional possibility for setting the plunger speed is to control the charging process of the actuator through a throttle device. Preferably, the dosing system, for example, a control valve, includes at least one controllable throttle device. The throttle device may be configured to control and / or regulate the pressure of the actuator, particularly the pressure medium within the actuator chamber, as a function of input parameters. Preferably, the throttle device may be configured to dynamically control and / or regulate the pressure of the actuator, particularly as a function of input parameters. Preferably, the throttle device may be controlled so that the pressure of the actuator during the (first) discharge movement is different from the pressure of the actuator during the (second) subsequent discharge movement, i.e., the pressure of the actuator can vary "every pulse".

[0077] Preferably, the throttle device may include at least one controllable proportional valve and / or a controllable pressure regulator. The throttle device may be configured to control and / or regulate the volumetric flow or flow rate of the pressure medium flowing into the actuator chamber. For example, the throttle may be arranged in the operating connection of the control valve and / or in the bore of the actuator base body. Preferably, depending on the control of the flow cross-section, there may be a reduction or additional increase corresponding, for example, to the maximum possible flow cross-section. Alternatively, in each case, a controllable proportional valve may be arranged in the compressed air connection or the exhaust connection of the control valve.

[0078] Furthermore, the throttle may be formed or controlled alternatively or additionally so that the inflow of the pressure medium into the actuator chamber is completely blocked at a specific point in time. Preferably, the proportional valve of the working port may be (completely) closed as soon as a specific pressure is applied to the actuator chamber during filling. Preferably, the throttle may be controlled so as not to exceed, for example, the maximum allowable pressure of the actuator chamber. In certain situations, this may cause the pressure of the filled actuator (deflecting the membrane) to become lower than the supply pressure. The dosing system may have a pressure sensor for measuring the pressure of the actuator chamber.

[0079] The throttle device can be implemented as a mechanical or manual throttle. Preferably, at least one input parameter can be transmitted to the operator of the dosing system, in which case the operator adjusts the throttle (also called an expansion valve) to achieve a specific (target) flow through the throttle and thereby achieve a desired plunger speed during the discharge movement of the plunger.

[0080] Preferably, the throttle device can be realized by an electronic throttle, for example, a proportional valve. Preferably, the throttle can be controlled by a control unit as a function of input parameters, for example, an actual plunger speed, to achieve a specific flow volume or a desired pressure in the actuator chamber. Alternatively or additionally, the throttle device can be controlled so as not to exceed a specific pressure in the actuator, particularly during charging. Particularly preferably, the throttle device can be controlled according to at least one input parameter to achieve a constant, assignable plunger speed, for example, during discharge movement and / or retraction movement.

[0081] Advantageously, the plunger speed can be set to a constant value during the discharge movement in operation by a controllable throttle device. Thus, the controllable throttle device represents a second alternative or additional variation for maintaining the plunger speed constant during operation and thereby further improving dosing accuracy.

[0082] It should be noted that the previously described throttle device, preferably formed to control and / or regulate the pressure of an actuator as a function of input parameters by a control and / or adjustment unit of the dosing system, does not limit the aforementioned dosing system according to the present invention but represents an independent partial aspect of the present invention. This means that such a throttle device may also be provided in, for example, a pneumatic actuator having a pneumatic cylinder or a dosing system of a conventional design having a fixed connection between a discharge element and a membrane.

[0083] To further improve the dosing results, the dosing system may be configured to set a specific speed profile of the discharge element during each discharge movement and / or retraction movement. Dynamically controlling the speed of the discharge element is also referred to as flank control. Preferably, the dosing system, preferably the control valve, may include at least one throttle device configured to control and / or regulate the pressure profile while charging the actuator with a pressure medium and / or while emptying or exhausting the actuator. Preferably, the control and / or regulation may occur as a function of at least one input parameter.

[0084] To this end, the throttle device may be configured to adjust the flow rate of the flowing fluid by locally (variably) contracting the flow cross-section in a manner that allows the filling process of the actuator chamber to be controlled in time. This means that the pressure increase in the actuator chamber can be controlled in time (the pressure profile can be controlled in time) by the throttle. Preferably, the throttle may be configured to dynamically control or regulate the flow rate during each discharge movement and / or during each retraction movement of the discharge element.

[0085] Preferably, the throttle device can be controlled so that the pressure increase in the actuator chamber is dynamic or variable, that is, so that the pressure in the actuator chamber does not increase continuously or linearly. The pressure of the actuator, particularly the actuator chamber, as a function of time (during charging or exhausting) is referred to here as the pressure profile. Preferably, the throttle device can be controlled so that the speed of the plunger varies during the exhaust movement, that is, so that the plunger has two or more different speeds or is controlled so that it accelerates to two or more different speeds in a single exhaust movement. Preferably, the speed of the plunger can be controlled and / or regulated throughout the entire plunger movement, that is, from the resting position until impact with the nozzle.

[0086] The throttle device can be realized by a controllable proportional valve. Preferably, at least one, for example, piezoelectric actuator having a variable flow can be used to control the velocity profile of the plunger with the highest possible resolution during the discharge process. Preferably, the electronically controllable piezoelectric actuator is part of the throttle device and can be controlled by a control unit to control the volumetric flow (flow rate) of the pressure medium flowing into the actuator and / or the pressure medium exiting the actuator without substantial delay. For example, the control valve can be configured so that the flow cross-section of the operating connection of the control valve (e.g., a 3 / 2-way valve or two 2 / 2-way valves) can be controlled (changed) by the actuator in substantial real-time during the inflow of the pressure medium into the actuator and / or the outflow of the pressure medium from the actuator.

[0087] Alternatively, the control valve may include two independently controllable proportional valves instead of a 3 / 2-way valve, thereby enabling simultaneous realization of the throttle device. Then, a first proportional valve for (time-controlled) charging of the actuator chamber and a second proportional valve for (time-controlled) exhaust of the actuator chamber may be used, wherein the two proportional valves may use the same or different bores of the actuator chamber. As a result, the pressure profile can be controlled or regulated separately during charging and exhaust.

[0088] For example, the input parameter on which the adjustment is performed may be the measurement signal from a speed sensor.

[0089] Preferably, a predetermined velocity profile of the plunger may function as an input parameter that can be generated and stored in the control unit, for example, according to the characteristics of the dosing material and / or dosing requirements. Preferably, the control unit can control (adapt) the pressure as a function of the actual velocity of the plunger so that a desired velocity profile is achieved during the discharge process while filling the actuator. For example, a throttle device may initially be controlled by a membrane to accelerate the plunger from the resting position to a very high velocity (strong inflow of the pressure medium into the actuator, i.e., a rapid increase in pressure within the actuator chamber) to achieve shearing of the dosing material. In the second stage of discharge movement, the plunger velocity may be reduced (reduction in the inflow of the pressure medium into the actuator, i.e., a slow rise in pressure within the actuator chamber) to achieve clean discharge of the dosing material from the nozzle.

[0090] Advantageously, the dosing system can be controlled by controlling the pressure profile and / or time profile of the actuator, particularly by a throttle device designed in this manner. This allows for the setting of a desired plunger travel speed profile (also known as flank control) during each stage of the discharge movement. Thus, advantageously, dosing accuracy can be further improved, and external influencing factors can be effectively compensated for. For example, it can compensate for variations in the dosing medium that may result from batch dependence (viscosity), temperature dependence, or material aging (adhesive curing process). Additionally, flank control can compensate for even small manufacturing tolerances or wear processes.

[0091] As previously mentioned, the throttle device may also be configured or controlled to regulate the pressure profile and / or time profile of the emptying even while the actuator is exhausting. This means that the plunger may have two or more different speeds or a determined speed profile even during the retraction movement. The regulation may preferably be performed as a function of input parameters, e.g., measurement data from a speed sensor, to achieve a predetermined speed profile of the plunger. Advantageously, the retraction speed of the plunger may be determined so as not to draw air through the nozzle opening of the nozzle during the retraction movement, thereby avoiding the formation of bubbles in the drop of dosing material subsequently discharged from the nozzle.

[0092] In principle, controlling and / or adjusting the pressure profile, preferably by a throttle device, while filling or emptying the actuator chamber to change the speed of the discharge element during discharge movement and / or retraction movement, is not limited to the aforementioned dosing system according to the present invention but represents an independent partial aspect of the present invention. This means that, for example, a pneumatic actuator having a pneumatic cylinder or a dosing system of a conventional design having a fixed connection between the discharge element and the membrane may also have the previously discussed throttle device, in which case such (known) dosing systems may be operated according to a desired plunger movement speed profile.

[0093] Preferably, the dosing system may also be configured to increase the uninterrupted service life of the dosing system. To this end, the actuator unit may be configured to use the pressure medium flowing out from the actuator or the actuator chamber as a cooling medium for cooling the control valve. Exhausting or emptying the actuator chamber is preferably performed by the exhaust connection of the control valve, in which case the exhaust connection is opened to the exhaust area of ​​the actuator unit.

[0094] For example, control valves, such as solenoid valves, generate heat that increases during operation as the clock frequency increases, and in this case, failure of the control valve may occur due to overheating. Preferably, an exhaust region is formed as a cavity in the housing of the dosing system to encircle or surround the entire control valve from the outside. Preferably, the pressure medium can be guided through the control valve to discharge as much heat as possible from the surface of the control valve. For example, a pressure medium such as compressed air can be used as a cooling medium because it is hardly heated as it passes through the actuator. Thus, the exhaust region, which can also be called a cooling region, forms a cooling device that cools the dosing system using the pressure medium. The housing may have a bore to discharge the pressure medium from the exhaust region.

[0095] To cool the control valve particularly effectively, the pressure medium can be actively cooled to a specific temperature, for example, by a refrigeration unit, before entering the housing. Thus, the control valve can be permanently maintained below the critical operating temperature. Additionally, regulating the active cooling can be considered; in this case, for example, the control valve may include a temperature sensor and transmit the corresponding measurement value to a control unit. The control unit can then control the refrigeration unit as a function of the measured value to maintain the temperature of the control valve below the critical threshold, thereby causing the refrigeration unit to provide a correspondingly cooled pressure medium.

[0096] Advantageously, this cooling device can reliably maintain the control valve below the critical operating temperature during operation, thereby improving the reliability of the dosing system. On the one hand, this allows the dosing system to operate even when the external temperature is high. On the other hand, since sufficient thermal energy can be discharged from the control valve even at very high clock frequencies, the clock frequency of the dosing system can be increased compared to conventional dosing systems.

[0097] To further improve the reliability of the dosing system, it is possible to provide pressure to the region between the actuator membrane and the plunger seal, and this pressure substantially corresponds to the cartridge pressure (the pressure of the dosing material within the dosing material cartridge). The plunger seal surrounds the plunger and is realized as part of the fluid unit of the dosing system. Preferably, the plunger seal is located opposite the outlet opening of the nozzle, where the plunger seal defines the nozzle chamber of the nozzle from above. Since the same pressure is substantially present on both sides of the plunger seal, the tendency for the dosing material to be pressurized through the seal during operation is offset. Advantageously, the life of the seal can be increased.

[0098] Alternatively, negative pressure, in particular, vacuum, can be provided between the actuator membrane, preferably its lower side, and the plunger seal. Thus, advantageously, the vacuum can increase the performance of the actuator or dosing system because it facilitates or supports the deflection of the membrane toward the nozzle. This can be particularly advantageous in media that are difficult to dose, such as dosing materials with high viscosity, for example.

[0099] In a method for controlling a dosing system (control method) so as to advantageously implement the previously described advantageous embodiment of the dosing system during operation, the pressure of a pressure medium flowing into the housing of the dosing system or into an internal pressure tank by a pressure regulator of the dosing system is controlled and / or regulated as a function of at least one input parameter such that the speed of the discharge element preferably corresponds to a target value, particularly when striking the nozzle during discharge movement. Preferably, the pressure regulator is controlled by a control unit of the dosing system.

[0100] The pressure of the pressure medium flowing into the actuator or actuator chamber and / or the pressure of the pressure medium exiting the actuator or actuator chamber is controlled and / or regulated by a throttle device of the dosing system, preferably as a function of at least one input parameter, so that the speed of the discharge element corresponds to a target value during each discharge movement and / or retraction movement. During operation, the control unit of the dosing system may continuously receive measurements from at least one sensor, preferably a speed sensor, and may perform a real-time comparison of the measured value (actual value) with a predetermined target value. Based on this monitoring, the throttle device is preferably controlled so that the pressure medium enters the actuator or exits from the actuator in a flow volume that achieves a desired plunger speed during discharge movement and / or retraction movement.

[0101] Furthermore, the control unit may control the throttle device so that the speed of the discharge element changes during a single discharge movement and / or a single retraction movement. Preferably, the discharge element may be accelerated to two or more different speeds during a single individual movement. Preferably, the control unit may control the flow rate of the pressure medium through the throttle device as a function of at least one input parameter, e.g., speed measurement data, to achieve a specific plunger movement speed profile during discharge and / or retraction movements. For example, the expansion valve may be controlled to first fill the actuator with a first pressure for a (single) discharge movement to reach a first discharge speed, and then fill the actuator with a second different pressure to reach a second discharge speed that may be different from the first discharge speed.

[0102] As mentioned, an expansion valve or throttle can also be used in a dosing system of a conventional design. As mentioned, this can be used to control and / or regulate the pressure of the pressure medium, for example, to change the speed of the discharge element during discharge movement and / or retraction movement. That is, regardless of the specific connection between the discharge element and the membrane, the dosing system can be operated by this control method to achieve a desired plunger movement speed profile.

[0103] The present invention is described in more detail below with reference to the attached drawings. In this case, the same components are provided by the same reference numerals in multiple drawings. The drawings are not typically scaled. The drawings illustrate schematic diagrams. Brief explanation of the drawing

[0104] FIG. 1 is a cross-sectional view of a dosing system according to one embodiment of the present invention. Figure 2 is a partial enlarged view of the dosing system of Figure 1. Figure 3 is an additional enlarged view of a part of the dosing system of Figures 1 and 2. FIG. 4 is a partial cross-sectional view of a dosing system similar to FIG. 3 according to an additional embodiment of the present invention. FIG. 5 illustrates an actuator unit of a dosing system according to one embodiment of the present invention. Figure 6 illustrates the dosing system of Figure 1 in a different functional position. FIG. 7 illustrates a method for controlling a dosing system according to one embodiment of the present invention. FIG. 8 illustrates a possible plunger movement speed profile according to one embodiment of the present invention. Specific details for implementing the invention

[0105] A specific embodiment of the dosing system (1) according to the present invention is now described with reference to FIG. 1. A cross-section of the dosing system (1) in a normal position during the intended operation of the dosing system (1) is illustrated herein. In this case, a nozzle (70) is positioned in the lower region of the dosing system (1) to discharge a drop of medium downward in the discharge direction (RM) through the nozzle (70). Where the terms "down" and "up" are used below, these terms always refer to the normal and customary position of the dosing system (1). However, this does not exclude the dosing system (1) from being used in other positions in special applications, for example, where a drop is discharged laterally. Depending on the medium, pressure, and the precise configuration and control of the entire discharge system, this is also fundamentally possible.

[0106] The dosing system (1) comprises, as essential components, an actuator unit (10) and a fluid unit (60) coupled to the actuator unit. The dosing system (1) presented herein further comprises a dosing material cartridge (64) coupled to the fluid unit (60).

[0107] In the embodiment of the dosing system (1) presented herein, the actuator unit (10) and the fluid unit (60) are implemented in the manner of mutually connectable plug-in coupling parts to form a quick coupling. Thus, advantageously, the actuator unit (10) and the fluid unit (60) can be connected to each other without tools to form the dosing system (1). The quick coupling includes a coupling mechanism (50) having a coupling spring (51) that holds a sphere (52) under constant tension. The coupling spring (51) and the sphere (52) are contained in the (first) actuator unit housing block (11a) and form a first plug-in coupling part. This is particularly clearly visible in FIG. 2, which illustrates a partial enlarged view of the dosing system of FIG. 1.

[0108] The coupling mechanism (50) has a plurality of spherical calottes (54) (only one is shown in FIG. 2) to which a sphere (52) can be engaged for coupling. The spherical calottes (54) are arranged in the second plug-in coupling portion (53) of the fluid unit (60), and the fluid unit (60) is contained in the (second) fluid unit housing block (11b). For coupling, the first plug-in coupling portion (actuator unit (10)) and the second plug-in coupling portion (fluid unit (60)) can be plugged together along a (virtual or imaginary) plug-in axis. For example, the fluid unit (60) can be plugged into the actuator unit (10) against the direction (RM) (see FIG. 1) and can be coupled to the actuator unit (10) at an appropriate rotational position.

[0109] Spherical cap-shaped portions (54) are arranged in the second plug-in coupling portion (53) of the fluid unit (60) so that the fluid unit (60) can be latched at different latching positions around the plug-in axis, that is, rotated at different rotational positions. A spring-biased sphere (52) in the plug-in coupling portion (53) engages at one of several possible latching positions to form a dosing system (1).

[0110] Accordingly, the dosing system (1) includes a housing (11) having two mentioned housing parts (housing blocks) (11a and 11b).

[0111] However, it is noted that each assembly (10, 60) can also be firmly connected to each other, for example by a fixing screw, to form a housing (11).

[0112] As can be seen in FIG. 1, the actuator unit (10) includes substantially all components that drive or move the discharge element (80) within the nozzle (70), wherein, for example, as described below, a pneumatic actuator (12) capable of operating the discharge element (80) of the fluid unit (60), a control valve (20), and a control unit (not shown in FIG. 1 and FIG. 2) capable of controlling the pneumatic actuator (12) and similar components.

[0113] The fluid unit (60) includes, in addition to the nozzle (70) and the supply line (62) supplying the medium to the nozzle (70), all other parts in direct contact with the medium, and elements necessary to assemble the related parts in contact with the medium together or maintain their positions in the fluid unit (60). Additionally, the fluid unit (60) further includes means for returning the discharge element (80) to a resting position or a starting position after dispensing the dosing material as described below.

[0114] Since the basic structure of the dosing system is known, for clarity, the components that at least indirectly affect the present invention are mainly illustrated here.

[0115] In the embodiments of the dosing system (1) illustrated herein (Figs. 1 and 2), as mentioned, the actuator unit (10) comprises a pneumatic actuator (12) that can be pressurized by a pressure medium, in this case, preferably compressed air. It is noted that in Figs. 1 and 2, the pneumatic actuator (12) and its coupling with the discharge element are illustrated only schematically. In particular, the membrane (13) of the actuator (12) is illustrated only schematically, that is, not the actual position or configuration of the membrane (13) when deflected or retracted during operation. This will be explained later with reference to Figs. 3 and 4.

[0116] A pneumatic actuator (12) (Fig. 1) is coupled to a fluid unit (60) to actuate a plunger (80) by controlling the pneumatic actuator (12) to discharge a desired amount of medium to be dosed from the fluid unit (60) at a desired time. In the case illustrated herein, the plunger (80) functions as a closing element (80) as it currently closes the nozzle opening (72). However, since most of the medium is already discharged from the nozzle opening (72) when the plunger (80) moves in the discharge direction (RA) (see Fig. 2), the plunger is referred to here as a discharge element (80). The coupling between the pneumatic actuator (12) and the plunger (80) will be described in detail later with reference to Fig. 3.

[0117] A pneumatic actuator (12) is arranged in the actuator unit (10) in the immediate vicinity of a control valve (20) for controlling the actuator (12). The control valve (20), for example, a pneumatic 3 / 2-way valve, is configured to supply a pressure medium, such as compressed indoor air, to the actuator (12) and / or discharge the pressure medium from the actuator (12). To this end, the actuator (12) is arranged in the actuator unit (10) such that the bore (17) of the actuator (12) interacts with the operating connection (23) of the control valve (20) and is spatially connected to the operating connection. This is particularly evident in FIG. 2.

[0118] The control valve (20) further includes a compressed air connection (22) and an exhaust connection (24), and depending on the control or switching position of the control valve (20), the compressed air connection (22) or the exhaust connection (24) interacts with or is connected to an operating connection (23). The control valve (20) is coupled to the circuit board (42) of the dosing system (see FIG. 1) by a connecting cable (21) and can be further controlled (e.g., electrically) by the control unit of the dosing system (1).

[0119] Referring to FIG. 2, a control valve (20) is arranged in the actuator unit (10) such that a compressed air connection (22) interacts with or is connected to a bore (25) (here, top left), and it can be seen that the bore (25) and the compressed air connection (22) have substantially the same diameter. Here, the bore (25) is realized as the discharge opening (25) of the internal pressure reservoir (32) (hereinafter also referred to as the pressure tank (32)) of the dosing system (1). The pressure medium can be supplied to the control valve (20) through this bore (25) (through the compressed air connection (22)) and then also supplied to the actuator (12) (through the operating connection (23) and bore (17).

[0120] The pressure tank (32) is located right next to the control valve (20). Therefore, since no connection line is required between the pressure tank (32) and the control valve (20), except for the bore (25), line loss of the printing medium can be significantly prevented. The pressure tank (32) extends into a housing block (11a) between the pressure medium supply device (30) and the discharge opening (25), which includes a connection point (31) (see FIG. 1) for an external pressure medium supply source (not shown), and represents a cavity or chamber of the dosing system (1). A pressure medium having a specific pressure in the direction (RD) can be supplied to the pressure reservoir (32) by the pressure medium supply device (30). In addition to what is shown herein, the external pressure medium supply line may additionally include a controllable pressure regulator as described with reference to FIG. 7.

[0121] The pressure tank (32) is formed to provide the pressure medium (DK) at a specific pressure during operation, in particular in cooperation with the pressure medium supply device (30) and the pressure regulator (see FIG. 6). The pressure of the pressure medium in the pressure tank (32) corresponds to the supply pressure of the actuator (12).

[0122] Here, the pressure tank (32) includes a pressure sensor (33) to determine the pressure of the pressure medium within the pressure tank (32) (see FIG. 1). The pressure sensor (33) is arranged here on the circuit board (42) of the dosing system (1). The circuit board (42) may include or be coupled with various other electronic components, for example, a temperature sensor (48) or a heating device (47) or a heating element (47). The circuit board (42) is connected to a connection device (40) that includes a connection point (41) for a connection cable of a control unit (not shown). On the one hand, the measurement signal of the pressure sensor (33) or an additional sensor of the control unit of the dosing system (1) may be supplied by the connection point (41), for example, a socket. On the other hand, the control unit can access various electrical components of the dosing system (1) by the connection device (40) and thus control, for example, the heating device (47). Additionally, the control unit can control the control valve (20) by means of a connecting device (40), a circuit board (42), and a connecting cable (21).

[0123] FIG. 1 also illustrates that the control valve (20) includes an exhaust connection (24) that interacts with or is connected to the bore (26) (here, top right) of the exhaust region (34) of the dosing system (1), and that the bore (26) and the exhaust connection (24) have substantially the same diameter. The pressure medium can be discharged from the actuator (12) by the exhaust connection (24) and the bore (26) and, advantageously, can still be used to cool the control valve (20). The exhaust region (34) is described later with reference to FIG. 6.

[0124] The control valve (20) can be controlled by the control unit of the dosing system (1) to operate the pneumatic actuator (12) in a desired manner. The control valve (hereinafter also referred to as the "pneumatic valve") (20) shown in FIG. 1, for example, a pneumatic 3 / 2-way solenoid valve, may be in an open state ("fill" position) in the normal position. Thus, in the normal position of the pneumatic valve (20), the pressure medium is transferred from the pressure reservoir (32) to the operating connection (23) through the compressed air connection (22) and the flow channel (27) located in the pneumatic valve (20) (shown here in dashed lines). The pressure medium flows into the pressure (supply pressure) inside the actuator chamber of the actuator (12) appearing in the pressure reservoir (32) at this first switching position of the control valve (20), and deflects the membrane of the actuator (12) and the plunger (80) accordingly downward in the discharge direction of the plunger (80), thereby discharging a drop of dosing material from the nozzle (70).

[0125] This means that in the normal position (first switching position) of the pneumatic valve (20), the actuator (12) is under a specific pressure, where the plunger tip (82) of the plunger (80) contacts the sealing seat (73) of the nozzle (70), i.e., the nozzle (70) or dosing system (1) is closed (see FIG. 2). However, this may differ from what is shown here in that in the normal position of the solenoid valve (20), where the membrane is consequently deflected to the maximum extent, the plunger tip (82) does not completely collide with the nozzle (70), where the discharge movement of the plunger (80) is stopped before the nozzle (70), i.e., stopped at a point spaced apart from the nozzle.

[0126] In the case illustrated in FIG. 2, the actuator (12) is filled with pressure applied immediately before the control valve (20), that is, the supply pressure of the actuator (12) also corresponds to the actuator filling pressure. However, in principle, it is also possible to fill / fill the actuator (12) with a pressure lower than the supply pressure or to fill the actuator (12) with a dynamic pressure profile. Thus, for example, a specific discharge travel speed profile of the plunger (80) can be realized. To achieve this, for example, the dosing system (1), for example, the solenoid valve (20) may be supplemented by one or more controllable actuators having variable throughput, for example, piezoelectric actuators. Such actuators (not shown) may be arranged, for example, in the area of ​​the actuation connection (23).

[0127] To return the actuator (12) to the idle position after dispensing the dosing material, the pneumatic valve (20) can be switched by the control unit so that the operating connection (23) is connected to the exhaust connection (24) (second switch position) by the internal flow channel (27') (see FIG. 6) of the solenoid valve (20). Then, the pressure medium flows into the exhaust area of ​​the actuator unit (10). This will be explained later with reference to FIG. 6.

[0128] As described above, the resting position of the actuator (12) exists when the membrane (13) and the discharge element (80) are in the resting position. The membrane (13) of the actuator (12), which is not currently pressurized by the pressure medium, returns to the resting position due to residual stress. In order for the plunger (80) to return to the resting position and release the nozzle opening (72), the plunger head (81) of the plunger (80) is pressed upward toward the control valve (20) by the return spring (84). The exact operation of the actuator (12) will be described in detail later with reference to FIGS. 3 and FIGS. 4.

[0129] Referring to FIG. 2, it is particularly evident that the fluid unit (60) of the dosing system (1) comprises a second housing portion (11b) and, as mentioned, is connected to the actuator unit (10) or its housing portion (11a) by quick coupling to form the housing (11). The fluid unit (60) comprises a plunger (80), wherein the contact surface (86) of the plunger head (81) is in direct contact with the surface (lower side) of the membrane (13) of the actuator (12), i.e., the surface of the membrane facing toward the plunger (80). Also, as is generally preferred in a dosing system, the plunger (80) is a single member, i.e., formed as a single member. A plunger (80), specifically a plunger head (81), is pressed axially upward into a membrane (13) by a spring (84) to be coupled to an actuator unit (10) (partially illustrated). The return spring (84) contacts a plunger bearing (83), and the plunger bearing is connected to a plunger seal (85) from below. In the case illustrated herein (Fig. 2), the membrane (13) (schematically illustrated) of the actuator (12) is pressed (into the operating position of the actuator (12)) by a pressure medium so that the plunger tip (82) contacts the sealing sheet (73) of the nozzle (70).

[0130] Unlike what is shown herein, when the actuator (12) is in a resting position, that is, when the membrane (13) of the actuator (12) is not pressurized and is not deflected, the plunger tip (82) is pushed away from the sealing sheet (73) of the nozzle (70) by the return spring (84). Then the plunger tip (82) is positioned at a distance from the sealing sheet (73) of the nozzle (70), so that the nozzle opening (72) is freed or unlocked.

[0131] The dosing material is supplied to the nozzle (70) through the nozzle chamber (71) connected to the supply channel (62) (see FIG. 2). The supply channel (62) is embedded here in the fluid body (61). Meanwhile, the supply channel (62) is connected to the dosing material cartridge (64). The supply channel (62) is closed from the outside by a clamping screw (65). The dosing material cartridge (64) is reversibly fastened to the housing (11) in the area of ​​the connection point (63). Additionally, the cartridge (64) is fastened here to the actuator unit (10) by a fixing element (45) (see FIG. 1).

[0132] To heat the dosing material in the area of ​​the nozzle (70) to a specific processing temperature, the dosing system (1) includes at least one heating device (47), for example, one or more heating plates (47) or heating foils (47). This is particularly evident in the enlarged view of FIG. 2. The heating device (47) may be controlled by a control unit. The heating device (47) is integrated here into the actuator unit (10) and first heats the coupling part of the actuator (10), and thus, for example, the coupling mechanism (50). As soon as the plug-in coupling part (53) of the fluid unit (60) is inserted into the coupling part of the actuator unit (10), the plug-in coupling part (53), and the dosing material in particular within the nozzle (70), is heated to a specific temperature. The plug-in coupling part (53) is designed to provide the best possible heat conduction in the direction of the nozzle (70). Here, the fluid unit (60) does not include a separate heating device, so it can be easily handled or disassembled even during operation.

[0133] To prevent the pneumatic actuator (12) and, in particular, the control valve (20) from overheating, the heating device (47) is substantially thermally separated from the pneumatic actuator (12) of the dosing system (1). When the dosing system is assembled as intended, that is, when the fluid unit (60) and the actuator unit (10) are combined together as shown in FIG. 2, the dosing system (1) includes a plurality of gas-filled cavities (46, 46'). The cavities (46, 46') are used to thermally separate the pneumatic actuator (12) from the fluid unit (60). The conduction of heat from the heating device (47) toward the actuator unit (10) and the control valve (20) can be effectively prevented by these cavities (46, 46').

[0134] FIG. 3 illustrates an additional enlarged portion of the dosing system (1) according to FIG. 1 and FIG. 2. However, the dosing system (1) at a different stage of the dosing process is illustrated herein. As previously described, FIG. 1 and FIG. 2 show the dosing system (1) during the discharge process of discharging the dosing material from the nozzle. In this case, the nozzle (70) of the dosing system is closed by the plunger (80) ( FIG. 1 and FIG. 2). In contrast, FIG. 3 illustrates the pneumatic actuator (12) in a resting position, that is, the membrane (13) of the actuator (12) is not deflected, and the discharge element (80) is in a resting position. Thus, in the pneumatic actuator (12) according to FIG. 3, the nozzle (70) is not closed by the discharge element (80).

[0135] The pneumatic actuator (12) of FIG. 3 is operably in contact with the operating connection (23) of the pneumatic valve (20) by means of a bore (17). As mentioned, the actuator (12) comprises a rigid actuator base body (14) formed by two components (14a, 14b). The two components (14a, 14b) are arranged relative to each other, preferably fixedly, and form a cavity between these components in a cross-sectional view. Alternatively, at the outer regions of each component (14a, 14b), the two actuator base body portions (14a, 14b) are placed in direct contact with each other and are detachably pressed against each other so that the membrane (13) can be replaced if necessary.

[0136] As mentioned, the (operating) membrane (13) is sealed between two rigid base body parts (14a, 14b) to form the actuator chamber (16) of the actuator (12). Here, it is evident that the actuator (12) comprises only a single membrane (13) to move the plunger (80). The membrane (13) is shown here in a resting position and is curved upward in the central region where the discharge element (80) contacts the membrane (13). The spring (84) and the discharge element (80) here press the membrane (13) against the upper actuator base body (14a) so that the membrane (13) contacts the upper actuator base body at least partially. Accordingly, the actuator base body (14a) here limits the upward stroke or deflection of the membrane (13). However, it is also conceivable to form the actuator (12) such that, for example, the actuator base body (14a) has an extension or protrusion (not shown) toward the membrane (13) in the area of ​​the plunger head (81) so that the membrane mainly comes into contact with the upper actuator base body (14a) at least partially in a horizontal resting position.

[0137] Although this is not visible in the cross-sectional view according to FIG. 3, the membrane (13) preferably has a circular base surface and is gas-tightly coupled in the entire circumferential direction to two base body parts (14a, 14b) of the rigid base body (14) at its edge region. To this end, the membrane (13) is pressed from below by the lower base body component (14b) at its edge region toward the upper base body component (14a). For sealing, a sealing ring (15), for example, an O-ring (15), is arranged between the membrane (13) and the upper component (14a).

[0138] As mentioned, the actuator chamber (16) of the actuator (12) is formed between the surface (upper side) of the membrane (13) facing opposite to the discharge element (80) and the upper rigid actuator base body part (14a). The actuator chamber (16) can be filled with a pressure medium by the bore (17) to deflect the membrane (13) downward from the resting position shown herein. This will be schematically illustrated again later with reference to FIG. 4.

[0139] The plunger head (81) is pressed toward the lower side (19) of the membrane (13) by a spring (84) to connect the discharge element (80) to the actuator unit. The return spring (84) is formed to apply this (spring) force to the plunger (80) so that the plunger maintains direct contact with the lower side (19) even in the resting position of the actuator (12). In the case illustrated herein, the plunger (80) pushes the membrane (13) (at least the central area of ​​the membrane (13)) upward beyond the horizontal resting position, where the deflection is limited by the component (14a).

[0140] FIG. 4 illustrates a cross-sectional view of a dosing system drawn in cross-section according to an additional embodiment. The difference from the dosing systems drawn so far (Figs. 1 to 3) is that the pneumatic actuator (12) here additionally includes a sensor (18) for determining the movement speed of the discharge element (80).

[0141] The sensor (18) is arranged in the upper actuator base body portion (14a) so as to be positioned on the plunger (80) and the virtual vertical line (corresponding to the longitudinal range of the plunger (80)). The sensor (18) and the plunger head (81) are positioned opposite each other on their respective different sides of the membrane (13). To determine the speed of the plunger (80) during each step of the discharge movement and / or retraction movement, the sensor (18) may include a position sensor (18) to detect the distance between the sensor (18) and the plunger head (81) as a function of time. For example, the sensor (18) may be a Hall sensor, and the plunger head (81) may include a magnet (not shown). The sensor (18) is coupled to a control unit (not shown here) of the dosing system (1) to transmit the measured data.

[0142] Also, referring to the detailed view in FIG. 4, it is clear that the membrane (13) is deformed to dispense the dosing material. As in FIG. 1 and FIG. 2, the actuator (12) is also shown here in the operating position. This means that the upper side of the membrane (13) is currently pressurized by the pressure medium. As can be seen here, the membrane (13) is not uniformly deflected downward toward the plunger (80) by the pressurization. Rather, there are regions of the membrane (13) that are moved further down and other regions that have almost no change in position.

[0143] By design, the edge region of the membrane (13) to which the membrane (13) is coupled to the actuator base body (14) is hardly deflected. Additionally, the region of the membrane (13) in contact with the plunger head (81) is relatively slightly deflected. This is because the plunger (80) is pressed toward the lower side (19) of the membrane (13) by the spring (84). Thus, the spring (84) sets the deflection of the membrane (13) against a specific force. However, the spring (84) is configured so that the membrane (13) overcomes the spring force of the spring (84) during deflection and deflects the plunger (80) to distribute a desired amount of dosing material in the direction of the nozzle.

[0144] In contrast, the central region of the membrane (13) located between the plunger head (81) and the edge region of the membrane (13) in the illustrated cross-section experiences a relatively strong downward deflection. Thus, the membrane (13) is deformed into a virtual "wave" during the deflection.

[0145] FIG. 5 illustrates, in a very schematic manner, the structure and control of an actuator unit according to one embodiment of the present invention. The actuator unit (10) includes an internal pressure reservoir (32) that maintains a pressure medium at a specific supply pressure. The pressure medium is supplied to a control valve (20) in the flow direction (RD). The control valve (20) is controlled by a control unit (not shown) so that the pressure medium flows into the actuator chamber (16) of a pneumatic actuator (12) in the direction (RD'). Depending on the configuration of the actuator unit (10), an optional throttle device (not shown) may be controlled to fill the actuator chamber (16) with the pressure medium at the supply pressure or to fill it at an actuator filling pressure that deviates from the supply pressure.

[0146] Due to being pressurized by a pressure medium, the membrane (13) and the discharge element (80) are deflected downward (RA) to distribute the dosing material.

[0147] In the next step, the control valve (20) is controlled by the control unit to exhaust the actuator chamber (16) immediately after dispensing the dosing material. The pressure medium leaves the actuator chamber (16) in the flow direction (RD''), flows to the control valve (20), and then leaves the control valve in the direction (RD'''). Due to the decrease in pressure in the actuator chamber (16), the membrane (13) swings back to the resting position. The discharge element (80) follows the movement of the membrane (13) immediately or simultaneously, and if necessary, the discharge element (80) also supports the movement of the membrane (13) and returns to the resting position by the spring (84). Accordingly, the cycle of dispensing the dosing material is completed.

[0148] FIG. 6 shows the dosing system of FIGS. 1 through 3 during the exhaust of the pneumatic actuator. The control valve (20) is controlled by a control unit (not shown) so that the operating connection (23) interacts with the exhaust connection (24). To this end, the control valve (20) is moved to a second switching position so that a flow channel (27') (shown here in dashed lines) inside the control valve (20) connects the two connections (23, 24). The pressure medium flows out from the actuator (12) through the bore (17), flows through the flow channel (27') to the exhaust connection (24), and is finally guided to the exhaust area (34). The plunger (80) is pushed upward from the nozzle (70) toward the actuator unit (10) by a spring (84) so ​​that a small gap (not shown) is formed between the plunger tip (82) and the sealing seat (73). The membrane (13) is shown here as being in a horizontal "intermediate position," that is, the membrane returns to its current resting position due to the exhaust of the actuator chamber.

[0149] The exhaust area (34) represents a cavity or chamber within the housing of the actuator unit (10). In this illustration, the chamber of the exhaust area (34) is covered with an inlet pressure medium (DE). The pressure medium has a low pressure within the exhaust area (34) as the actuator supply pressure and is therefore referred to as the expanded pressure medium (DE). On one hand, the exhaust area (34) is immediately adjacent to the control valve (20) by a bore (26), and on the other hand, has a bore (not shown) to the outside of the dosing system. As illustrated herein, the exhaust area (34) surrounds a significant portion of the control valve (20) from the outside.

[0150] The exhaust area (34) is spatially separated from the pressure tank (32) of the actuator unit (10) in terms of control technology. Here, the pressure tank (32) is filled with a compressed pressure medium (DK), and the chamber forming the pressure tank (32) is covered with the pressure medium (DK).

[0151] The pressure medium flowing into the exhaust area (34) may be guided through the control valve, for example by a flow guide element, to dissipate as much heat as possible from the surface of the control valve (20). For example, the pressure medium, such as compressed air, may be used as a cooling medium as it is hardly heated by passing through the actuator (12). In particular, because the volume of the exhaust area (34) is relatively large compared to the actuator chamber, the pressure of the pressure medium in the exhaust area (34) may be significantly lower than the pressure in the pressure reservoir (32) and / or actuator chamber, for example.

[0152] FIG. 7 illustrates a schematic diagram of a method for controlling a dosing system (1) according to an embodiment of the present invention. Here, the dosing system (1) includes a housing (11) that encloses an essential component of an actuator unit (10) and a fluid unit. The dosing system (1) further includes a control unit (43) having a plurality of connecting cables (44) to control each component of the dosing system (1) separately.

[0153] On the one hand, the control unit (43) is coupled to the pressure regulator (35) to control and / or regulate the pressure of the pressure medium flowing into the internal pressure tank (32). The pressure regulator (35) is coupled to the pressure medium source (37), where, for example, it is arranged outside the housing (11) of the dosing system (1) as a component of the actuator (10). An external pressure reservoir (36) is optionally arranged between the pressure regulator (35) and the internal pressure tank (32). The pressure regulator (35) can be controlled by the control unit (43) as a function of input parameters, preferably, for example, plunger speed, so that a specific pressure exists in the external pressure tank (36) or the internal pressure tank (32) to achieve a constant plunger speed during the discharge process.

[0154] On the other hand, to control the actuator (12), the control unit (43) can control the control valve (20) to fill the actuator chamber of the actuator (12) with pressure medium (from the internal pressure tank (32)) or exhaust it (through the pressure medium outlet (DA). The actuator (12) of the dosing system (1) is coupled to a sensor (18), for example, a position sensor (18), where the measurement data is transmitted to the control unit (43) as an input parameter.

[0155] The control unit (43) processes these input parameters and other input parameters, for example, from the pressure sensor of the internal pressure tank (32) and can use them to control and / or regulate ("flank control") the plunger speed or the profile of the plunger speed. Based on the measured values, the control unit (43) controls, for example, the pressure regulator (35) so that a specific target pressure (supply pressure) of the pressure medium exists in the internal pressure tank (32) to achieve a constant plunger speed.

[0156] Alternatively or additionally, the control unit (43) may control a throttle device (28) to regulate the flow of a pressure medium, for example, using a piezoelectric actuator (28) in the area of ​​the control valve (20), as a function of input parameters to achieve a specific plunger speed or a desired speed profile during the discharge movement and / or retraction movement of the plunger (80).

[0157] The control unit (43) may further control the heating device (47) of the dosing system (1) to heat the dosing material in the nozzle (70) to a desired temperature. The control unit (43) may preferably control and / or adjust the heating device (47) as a function of a temperature measurement, wherein the temperature measurement is determined by a temperature sensor (48).

[0158] The control unit (43) can also access a second pressure regulator (35') that controls the pressure of the pressure medium (cartridge pressure) within the dosing material cartridge (64).

[0159] FIG. 8 schematically illustrates a possible plunger movement speed profile according to one embodiment of the present invention. Control of the speed profile is also referred to as flank control. The relative position (PS) of the plunger tip with respect to the relative time (t) of the ejection process is shown. The position (PD) of the sealing sheet within the nozzle in the dosing system is shown here by a dashed line.

[0160] The plunger is in the resting position before the ejection process begins at time (T1). This means that the tip of the plunger is at the farthest possible distance from the nozzle, so that the nozzle of the dosing system is in an unlocked state.

[0161] At time (T2), the actuator is filled to a high pressure by the pressure medium, increasing the discharge speed of the plunger. For example, to achieve this, the piezoelectric actuator can be fully opened to allow the maximum possible airflow.

[0162] At time (T3), for example, the ejection speed of the plunger is slowed down just before the plunger tip strikes the sealing sheet of the nozzle. For example, the airflow through the pneumatic actuator is reduced. Thus, at time (T4), the plunger tip strikes the sealing sheet of the nozzle at a low speed, which can improve the dosing accuracy of a specific dosing material.

[0163] It is worth noting that, for the sake of completeness, such flank control is possible even during the retracted movement of the plunger.

[0164] Finally, it is noted once again that the dosing system described in detail above is merely an exemplary embodiment that can be modified in various ways by those skilled in the art without departing from the scope of the invention. For example, the dosing system may include additional sensors to determine relevant operating parameters, for example, a sensor to determine the temperature of a control valve. Furthermore, the singular form of the element does not exclude the possibility that there may be multiple such elements. Explanation of the symbols

[0165] 1: Dosing System 10: Actuator unit 11: Housing 11a, 11b: Components of the housing block / housing 12: Actuator 13: Membrane 14: Actuator base body 14a, 14b: Components of the actuator base body 15: Actuator sealing ring 16: Actuator chamber 17: Bore of the actuator chamber 18: Sensor 19: Lower side of the membrane 20: Control valve 21: Control valve connection cable 22: Compressed air connection 23: Operating connection 24: Exhaust connection 25: Pressure tank discharge opening / bore 26: Bore of the exhaust area 27, 27': Flow Channel 28: Throttle device 30: Pressure medium supply device 31: Connection point 32: Pressure reservoir 33: Pressure sensor 34: Exhaust Area / Cooling System 35, 35': Pressure regulator 36: External pressure reservoir 37: Pressure medium source 40: Connection part 41: Connection point for connecting cable 42: Circuit board 43: Control Unit 44: Control unit connection cable 45: Fixed element 46, 46': Joint 47: Heating device 48: Temperature sensor 50: Connecting mechanism 51: Connecting spring 52: Ball 53: Plugin Integration Section 54: Spherical hat shape part 60: Fluid Unit 61: Fluid body 62: Supply Channel 63: Media cartridge connection point 64: Media cartridge 65: Clamping screw 70: Nozzle 71: Nozzle chamber 72: Exit opening 73: Sealing sheet 80: Emission element / plunger 81: Plunger head 82: Plunger Tip 83: Plunger bearing 84: Plunger Spring 85: Plunger seal 86: Contact surface DE: Expanded pressure medium DK: Compressed pressure medium DA: Pressure medium outlet PD: Location of the sealing sheet PS: Position of the plunger tip RA: Plunger discharge direction RD, RD', RD'', RD''': Flow direction of the pressure medium RM: Discharge direction of dosing material t: Discharge transit time T1, T2, T3, T4: Time

Claims

Claim 1 As a dosing system (1) for dosing a dosing material, the dosing system (1) comprises a housing (11) including a nozzle (70) and a supply channel (62) for dosing material, a discharge element (80) movably mounted on the housing (11), and an actuator unit (10) coupled to the discharge element, - the actuator unit (10) comprises an actuator (12) having a membrane (13) pressurized by a pressure medium to move the discharge element (80) in a discharge direction (RA), wherein one or more of a gaseous material and a liquid material are used as the pressure medium, and the pressure medium directly strikes a surface of the membrane (13) facing away from the discharge element (80), - the discharge element (80) is formed separately from the membrane, and the surfaces of the membrane (13) by a force acting on the discharge element (80) to be coupled to the actuator unit (10) A dosing system characterized by being pressurized toward a surface (19) facing the above-mentioned discharge element (80). Claim 2 A dosing system according to claim 1, wherein the dosing system (1) is formed such that the force acting on the discharge element (80) for coupling is directed in a direction opposite to the discharge direction (RA) of the discharge element (80). Claim 3 A dosing system according to claim 1 or 2, wherein the dosing system (1) is formed such that the discharge element (80) is pressed to the surface (19) by at least one spring device (84) so ​​as to be coupled to the actuator unit (10). Claim 4 A dosing system according to claim 1, characterized in that the membrane (13) is formed in a disc shape. Claim 5 A dosing system according to claim 1, wherein the membrane (13) is characterized by having no cavity. Claim 6 A dosing system according to claim 1, wherein the housing (11) of the dosing system (1) includes a reservoir (32) for the pressure medium. Claim 7 A dosing system according to claim 1, wherein the housing (11) of the dosing system (1) includes a reservoir (32) for the pressure medium, and the reservoir (32) is immediately adjacent to a control valve (20) of the actuator unit (10) for controlling the actuator (12). Claim 8 A dosing system characterized in that, in claim 6 or 7, at least one pressure sensor (33) is arranged in the reservoir (32). Claim 9 A dosing system according to claim 7, characterized in that the actuator unit (10) is formed to use the pressure medium flowing out of the actuator chamber (16) of the actuator (12) as a cooling medium for cooling the control valve (20). Claim 10 A dosing system according to claim 1, wherein the dosing system (1) comprises at least one sensor (18) for measuring the movement speed of the discharge element (80). Claim 11 A dosing system according to claim 1, wherein the dosing system (1) comprises one or more pressure regulators (35) for controlling the pressure of the pressure medium as a function of input parameters by a control unit (43) of the dosing system (1). Claim 12 A dosing system according to claim 1, wherein the control valve (20) of the dosing system (1) for controlling the actuator (12) comprises at least one throttle device (28) formed to control the pressure of the actuator (12) as a function of an input parameter by the control unit (43) of the dosing system (1). Claim 13 A dosing system according to claim 1, wherein the control valve (20) of the dosing system (1) for controlling the actuator (12) comprises at least one throttle device (28) formed to control a pressure profile while filling the actuator (12), while emptying the actuator (12), or while filling and emptying the actuator (12). Claim 14 A dosing system according to claim 1, wherein the dosing system (1) is formed such that pressure is maintained in the region between the membrane (13) and the plunger seal (85), and the pressure essentially corresponds to the cartridge pressure. Claim 15 A dosing system according to claim 1, wherein the dosing system (1) is formed such that a negative pressure is maintained in the area between the lower side of the membrane (13) and the plunger seal (85), the plunger seal (85) surrounds the discharge element (80) and is formed as part of the fluid unit of the dosing system (1), the plunger seal (85) is located opposite the outlet opening of the nozzle (70), and the plunger seal (85) defines the nozzle chamber of the nozzle (70) from the top. Claim 16 A method for controlling a dosing system (1) for dosing a dosing material, wherein the dosing system (1) comprises a housing (11) including a nozzle (70) and a supply channel (62) for the dosing material, a discharge element (80) movably mounted on the housing (11), and an actuator unit (10) coupled to the discharge element, and a step of pressurizing a membrane (13) of an actuator (12) of the actuator unit (10) with a pressure medium to move the discharge element (80) in a discharge direction (RA), wherein one or more of a gaseous material and a liquid material are used as the pressure medium, and the pressure medium directly strikes a surface of the membrane (13) facing opposite to the discharge element (80), and a step of pressurizing the discharge element (80) toward a surface (19) of the membrane (13) facing the discharge element (80) by means of a force acting on the discharge element (80) A method for controlling a dosing system characterized by including the step of combining with an actuator unit (10). Claim 17 A method for controlling a dosing system according to claim 16, wherein the pressure of the pressure medium is controlled as a function of an input parameter such that the speed of the discharge element (80) corresponds to a target value during discharge movement. Claim 18 A method for controlling a dosing system according to claim 16 or 17, wherein the pressure of a pressure medium flowing to the actuator (12), the pressure of a pressure medium flowing out of the actuator (12), or the pressure of the pressure flowing to the actuator (12) and the pressure of the pressure medium flowing out of the actuator (12) are controlled as a function of an input parameter such that the speed of the discharge element (80) corresponds to a target value during discharge movement or retraction movement, or corresponds to a target value during discharge movement and retraction movement. Claim 19 A method for controlling a dosing system according to claim 16, wherein the throttle device (28) of the dosing system (1) is controlled by the control unit (43) of the dosing system (1) such that the speed of the discharge element (80) changes during discharge movement or retraction movement, or changes during discharge movement and retraction movement.

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