Actuator module

Abstract

The invention relates to an actuator module (1) having a tightly closed module housing (3) which extends longitudinally in an axial direction (RAX) and which has at least one piezo actuator (2) arranged in the module housing (3), and having an electrical interface (6a, 6b) at least for the piezo actuator (2), which interface (6a, 6b) is guided through a module housing wall (3w), wherein a module housing interior (3i) located between the piezo actuator (2) and the module housing wall (3w) comprises a potting compound (4) which electrically insulates the module housing wall (3w) from the piezo actuator (2) and is designed as a thermally conductive, in particular with a thermally conductive auxiliary material, and wherein the module housing wall (3w) of the module housing (3) has a corrugated bladder (10, 20, 30, 40) with a corrugated contour (10, 20, 30, 40), wherein at least one section (14, 34l, 34r, 44l, 44r) of the corrugated contour (10, 20, 30, 40) is helically formed in the axial direction (RAX). The invention further relates to a metering system (50) having such an actuator module (1).

Description

(19) State Intellectual Property Office (12) Invention Patent Application (10) Application Publication Number (43) Application Publication Date (21) Application Number 202480037080.X (22) Application Date 2024.05.29 (30) Priority Data 102023115413.3 2023.06.13 DE (85) PCT International Application Entering National Phase Date 2025.12.02 (86) PCT International Application Application Data PCT / EP2024 / 064765 2024.05.29 (87) PCT International Application Publication Data WO2024 / 256174 DE 2024.12.19 (71) Applicant: Micros Dispensing Technology GmbH, Holzkirchen, Germany (72) Inventors: M. Fritz, S. Schmidberg, W. Hermitch (74) Patent Agency: Beijing Panhua Law Firm, 11336 Patent Attorney: Guo Jiayin (51) Int.Cl. H10N 30 / 50 (2006.01) H10N 30 / 88 (2006.01) B05C 5 / 00 (2006.01) (54) Invention Title: Actuator Module (57) Abstract: This invention relates to an actuator module (1) having a tightly sealed module housing (3) extending longitudinally in the axial direction (RAX), the module housing having at least one piezoelectric actuator (2) arranged in the module housing (3), and the actuator module having at least one electrical interface (6a, 6b) for the piezoelectric actuator (2), the interface (6a, 6b) being guided through the module housing wall (3w), wherein the module housing cavity (3i) located between the piezoelectric actuator (2) and the module housing wall (3w) includes a potting compound (4), the potting compound electrically insulates the module housing wall (3w) from the piezoelectric actuator (2), and is configured to be thermally conductive, in particular having a thermally conductive auxiliary material, wherein the module housing wall (3w) of the module housing (3) has corrugated bladders (10, 20, ... 30, 40), the corrugated bladder has corrugated profiles (10, 20, 30, 40), wherein at least one segment (14, 34l, 34r, 44l, 44r) of the corrugated profiles (10, 20, 30, 40) is helically constructed in the axial direction (RAX). Furthermore, the present invention relates to a metering system (50) having such an actuator module (1). Claims 2 pages Description 21 pages Drawings 11 pages CN 121444644 ​​A 2026.01.30 CN 1 21 44 46 44 A 1. An actuator module (1) having a tightly sealed module housing (3) extending longitudinally in the axial direction (RAX), the module housing having at least one piezoelectric actuator (2) arranged in the module housing (3).Furthermore, the actuator module has at least one electrical interface (6a, 6b) for the piezoelectric actuator (2), the interface (6a, 6b) being guided through the module housing wall (3w), wherein the module housing cavity (3i) located between the piezoelectric actuator (2) and the module housing wall (3w) comprises a potting material (4) that electrically insulates the module housing wall (3w) from the piezoelectric actuator (2) and is configured to be thermally conductive, in particular having a thermally conductive auxiliary material, wherein the module housing wall (3w) of the module housing (3) has corrugated bladders (10, 20, 30, 40) having corrugated profiles (10, 20, 30, 40), wherein at least one segment (14, 34l, 34r, 44l, 44r) of the corrugated profiles (10, 20, 30, 40) is constructed in a spiral shape along the axial direction (RAX). 2. The actuator module according to claim 1, wherein the filler material (4) comprises a base material (4a) and an auxiliary material (4b), wherein, preferably, the base material (4a) is a hardened material (4a), and the auxiliary material (4b) is at least particulate, thermally conductive and dielectric, wherein the auxiliary material (4b) is arranged in the filler material (4) such that heat is drawn from the piezoelectric actuator (2) to the module housing wall (3w) during operation through the filler material (4), especially through the auxiliary material (4b). 3. The actuator module according to claim 1 or 2, wherein the helical segments (14, 34l, 34r, 44l, 44r) begin at intervals (a10, a20, a30, a40) along the axial direction (RAX) with respect to the corresponding end sides (11, 12) of the module housing (3), and extend from there at least segmentally toward the other end sides (12, 11), preferably at least to the middle of the bellows (10, 20, 30, 40). 4. The actuator module according to any of the preceding claims, wherein the module housing wall (3w) of the module housing (3) has flat segments (21, 22, 41, 42) adjacent to the helical segments (14, 34l, 34r, 44l, 44r) in the corresponding end regions near the corresponding end sides (11, 12). 5. The actuator module according to any one of the preceding claims, wherein the module housing wall (3w) and / or the bellows (20*) of the module housing (3) has at least one module housing edge recess (3a), preferably four module housing edge recesses (3a), wherein the at least one module housing edge recess (3a) is particularly preferably having a concave cross-section. 6. The actuator module according to any one of the preceding claims, wherein,The bellows (30, 40) have at least two opposing helical segments (34l, 34r, 44l, 44r) in the axial direction (RAX), wherein, preferably, at least two of these helical segments (34l, 34r, 44l, 44r) having opposing winding directions (WRAX, AZ) are separated from each other. 7. The actuator module according to any one of the preceding claims, wherein at least two helical segments (34l, 34r, 44l, 44r) are separated from each other by a flat segment (43), which is preferably arranged in the middle of the bellows (40), from which the helical segments extend in the axial direction (RAX) toward the end sides (11, 12). 8. The actuator module according to any one of the preceding claims, wherein at least one helical segment (14, 34l, 34r, 44l, 44r) of the bellows (10, 20, 30, 40) has a pitch (19s) of at least 1 mm, preferably at least 5 mm, particularly preferably at least 10 mm, and / or a pitch of up to 35 mm, preferably up to 20 mm, particularly preferably up to 15 mm. 9. The actuator module according to any one of the preceding claims, the actuator module having a flexible outer sleeve (47), wherein the outer sleeve (47) has at least two openings. 10. A metering system (50) for metering material (D), having a nozzle (54) for discharging the metering material (D), a supply channel (56) for metering the material (D), a discharge element (53a), and at least one actuator module (1) coupled to said discharge element (53a), wherein the metering system (50) has a housing (57) with at least one columnar recess (58, 58*), wherein, during metering operation, the actuator module (1) according to any one of claims 1 to 9 is preferably precisely fitted into said recess, wherein, for cooling purposes, the housing (57) has inlets (58iax, 58irad) into said recess (58iax, 58irad). For introducing cooling medium (M) into a groove (17) on the outer side of the bellows (10, 20, 30, 40), and the housing (57) having at least one outlet (58orad) exiting the recess (58, 58*) for discharging the cooling medium (M) from the groove (17). 11. The metering system according to claim 10, wherein the recess (58) of the metering system (50) has at least one radial inlet (58irad) and / or a radial outlet (58irad) when the actuator module (1) having the module housing (3) is installed in the metering system (50),The radial inlet and / or radial outlet are preferably located substantially at the height (he) of the upper end section and / or the height (hf) of the lower end section of the module housing (3). 12. The metering system according to claim 10 or 11, wherein at least one of the walls (58w) of the recess (58, 58*) that axially defines the housing (57) has an inlet (58iax) or an outlet, or wherein one of the walls (58w) has an inlet (58iax) and the other wall has an outlet. 13. The metering system according to any one of claims 10 to 12, wherein, when the actuator module (1) is loaded as specified, the recess (58) has an inlet (58irad) for introducing the cooling medium (M) in the radial wall (58w) centrally located between the end sides (11, 12) of the module housing (3). 14. The metering system according to any one of claims 10 to 13, wherein, in the metering system (50) having a transmission mechanism (60), an outlet (59o) is arranged in the region of the transmission mechanism (60) and / or the discharge element (53a), the transmission mechanism being arranged in an additional recess (59) between the piezoelectric actuator (2) and the discharge element (53a), and / or wherein at least one inlet (58iax) is constructed at the axial end region of the bellows (10, 20, 30, 40) for preferably introducing the cooling medium (M) from the axial direction (RAX). 15. The metering system according to any one of claims 10 to 14, wherein, preferably in a metering system (50) having an inlet (58iax) in the end region of the bellows (10, 20, 30, 40) on the end side of the piezoelectric actuator (2), the housing (57) has an additional recess (59) on the front side of the piezoelectric actuator (2), preferably extending transversely thereto, in which a transmission lever (63) is arranged, the transmission lever transmitting the longitudinal extension of the piezoelectric actuator (2) via the lever arm of the transmission lever (63) to the discharge element (53a) of the elastically supported push rod device (53), wherein the outlet (59o) for the cooling medium (M) is arranged in the region of the additional recess (59), close to the elastically supported push rod device (53). Claims 2 / 2 Page 3 CN 121444644 ​​A Actuator Module Technical Field

[0001] The present invention relates to an actuator module having a hermetically closed module housing extending longitudinally in the axial direction, the module housing having at least one piezoelectric actuator arranged in the module housing, and having at least one electrical interface for the piezoelectric actuator.This invention also relates to a metering system having such an actuator module. Background Art

[0002] Piezoelectric ceramic multilayer actuators, or simply piezoelectric actuators, consist of multiple stacked thin layers of piezoelectric material, such as lead zirconate titanate. In such multilayer piezoelectric actuators (also called “multilayer elements,” “piezoelectric stacks,” or “piezoelectric piles”), multiple thin piezoelectric elements are cascaded together with internal electrodes located therebetween. The internal electrodes are alternately directed onto the surface of the piezoelectric actuator, wherein two external electrodes are connected to their respective internal electrodes. The internal electrodes are electrically parallel and combined into two groups, which constitute the connecting electrodes of the piezoelectric actuator. When a voltage is applied to the connecting electrodes, the voltage is transmitted in parallel to the internal electrodes, thereby causing an electric field in the piezoelectric material layers. The sum of the mechanical deformations of the individual layers of the piezoelectric material produces the available strain and / or force of the piezoelectric actuator.

[0003] Piezoelectric actuators are used in various technical fields, such as in regulating and positioning drives, or in metering systems for the targeted metering of liquid to viscous materials, particularly in so-called jet valves. A particular advantage of piezoelectric actuators is, for example, their high stiffness and pressure load capacity, enabling high position resolution, exhibiting rapid response characteristics and causing high acceleration, and operating, in principle, without wear.

[0004] Despite these advantages, heat dissipation of piezoelectric actuators has historically been insufficient. This is especially true for piezoelectric actuators arranged in an enclosure to prevent external influences, such as a closed housing containing the piezoelectric actuator, where adequate heat dissipation cannot be guaranteed during operation. The temperature of the piezoelectric actuator in any control state affects its geometry, and also its longitudinal extension in the (unconnected) stationary state.

[0005] Due to length changes caused by heat, especially due to insufficient heat dissipation of the piezoelectric actuator during operation, the longitudinal extension of the piezoelectric actuator due to the piezoelectric actuator being turned on and / or the resulting force and / or the position of the piezoelectric actuator within the machine may deviate from the determined target value (Sollwert). However, because particularly high accuracy is required when the piezoelectric actuator is running in many applications, length changes of the piezoelectric actuator due to temperature should be avoided as much as possible.

[0006] Therefore, known piezoelectric actuators, especially those housed in sealed enclosures, such as those in metal module housings, are used only in limited ways in many technical fields, where it is necessary to use specific media, such as hygroscopic media, within the module housing. Especially for the jet valves mentioned at the beginning, which currently typically operate at high clock frequencies above 1 kHz, where correspondingly large heat loss is generated in the piezoelectric actuators,For actuator modules, it is desirable to achieve sufficient heat dissipation from the surface of the piezoelectric actuator while simultaneously protecting the piezoelectric actuator from environmental damage for reliable operation.

[0007] The object of the present invention is to provide an actuator module with a tightly sealed housing, and a metering system for an actuator module having such a specification (page 1 / 21, CN 121444644 ​​A), which avoids or at least reduces the disadvantages described above.

[0008] This object is achieved by the actuator module according to claim 1 and the metering system according to claim 10.

[0009] The actuator module according to the invention has a tightly sealed, especially self-sealing, closed module housing. The module housing extends longitudinally, especially in the longitudinal direction, along the axial direction. In other words, the direction of the longest extension of the module housing is called the axial direction. The axial direction is preferably parallel to the longitudinal extension of the piezoelectric actuator arranged in the module housing. Preferably, the module housing is longer in the axial direction than in the direction perpendicular to the axial direction. Preferably, the module housing can be constructed or shaped substantially “hollow cylindrical”, i.e., having a circular cross-section.

[0010] At least one piezoelectric actuator is arranged inside the module housing, which is preferably completely and tightly sealed. For example, it can be oriented centrally therein. However, it is also conceivable in principle that two or more piezoelectric actuators are tightly sealed within the same module housing. For example, two independently controllable piezoelectric actuators can be arranged substantially parallel to each other in the same module housing. The invention will now be described by means of a module housing having only one piezoelectric actuator, without limitation thereto and unless otherwise stated.

[0011] The piezoelectric actuator can be, in particular, a piezoelectric ceramic multilayer actuator having multiple layers in the longitudinal direction. The actuator module has at least two electrical interfaces for the piezoelectric actuator. The electrical interfaces are guided through the module housing wall of the module housing, in particular tightly sealed and electrically insulating.

[0012] Within the scope of the invention, the term “tightly sealed” is understood to mean that the module housing is constructed such that no material can pass through the module housing or no material can pass through the closed module housing. The module housing is "tightly" sealed, preventing solids and / or liquids and / or gases from entering the housing from the outside during actuator module operation. In this respect, the tightly sealed module housing can also be called an impermeable module housing, its impenetrable construction ensuring that nothing can intrude or leak out. The module housing preferably constitutes an "absolutely sealed" enclosure or surrounding portion of the piezoelectric actuator relative to its surrounding environment; that is, the piezoelectric actuator is externally surrounded or encapsulated by the module housing. An "absolutely sealed" module housing is understood, in particular, to prevent the exchange of air and / or water molecules through the module housing. Accordingly,The module housing can be "absolutely sealed" at least (relatively) with respect to air and / or water molecules for a specific operating time, especially to prevent long-term diffusion of water molecules through the material of the module housing during operation. The sealing of the module housing can be verified, for example, by a helium leak test. The module housing can be, in particular, a deep-drawn module housing, as described later.

[0013] Thus, the module housing differs from known encapsulations (e.g., metal sleeves) that are only pushed onto the piezoelectric actuator, wherein individual piezoelectric actuator regions (e.g., actuator ends) protrude from the sleeve. Therefore, such a sleeve is not a "tightly" sealed module housing in the sense of the present invention.

[0014] Furthermore, a potting compound is arranged in the housing cavity inside the module housing, located between the piezoelectric actuator, especially the surface of the piezoelectric actuator, and the module housing wall, especially the inner side, which, especially during the operation of the piezoelectric actuator, makes the module housing wall electrically insulating relative to the piezoelectric actuator. The insulation resistance of the basic components of the potting compound, especially the base material, such as silicone, is preferably at least 1.1012 Ω·cm, preferably at least 1.1015 Ω·cm, especially at least 1.1016 Ω·cm or greater.

[0015] It should be explicitly mentioned again here that in the case of more than one piezoelectric actuator in the inner cavity of the module housing, the potting compound can be introduced either between the piezoelectric actuators or around the piezoelectric actuators between the module housing wall and the piezoelectric actuators.

[0016] According to the invention, the potting compound is thermally conductive. Preferably, the potting compound is thermally conductive such that the heat generated by the piezoelectric actuator during operation can be conducted outward from the inside, especially from the surface of the piezoelectric actuator, through the potting compound to the module housing wall. The heat conducted from the piezoelectric actuator can be, in particular, the heat loss generated during the operation of the piezoelectric actuator. Preferably, the potting compound may include at least one thermally conductive auxiliary material to contribute to the thermal conductivity of the potting compound. Specification 2 / 21 pages 5 CN 121444644 ​​A

[0017] The thermal conductivity of the filling material (in the inner cavity of the module housing) can be at least 0.5 W / (m·K), preferably at least about 1.0 W / (m·K), preferably at least about 1.5 W / (m·K), further preferably at least about 2.0 W / (m·K), particularly preferably at least about 2.25 W / (m·K), and especially at least about 2.45 W / (m·K).

[0018] Furthermore, here, the module housing wall of the module housing has a corrugated bladder with a corrugated profile. It can be specified that only certain portions of the module housing wall have corrugated bladders, wherein at least one region of the housing wall is configured without corrugated bladders. For example, the module housing end side defining the module housing in the axial direction can be configured without corrugated bladders. Here, corrugated profile is understood as the waveform structure of the surface of the module housing wall, and / or the particularly outer surface of the module housing wall.The waveform structure alternately has depressions or recesses and bulges in the axial direction of the module housing. Preferably, the recesses can be configured as concave and the bulges as convex. The bellows are preferably configured as an integrated circumferential surface of the module housing wall in the axial direction, between the first end side or head side (e.g., with an electrical interface, above) and the second end side or end side (e.g., closed, below), particularly opposite to the first end side.

[0019] As will be described more precisely below in the description of the metering system with at least one such actuator module according to the invention, the module housing wall with bellows is configured to encapsulate a piezoelectric actuator, which is preferably precisely fitted into or can be fitted into a cylindrical recess in the housing of the metering system.

[0020] According to the invention, at least one segment of the bellows profile is helical or coiled in the axial direction of the module housing, or about the axial direction. This means that the segment has at least one coiled ridge, which, together with an adjacent coiled, especially grooved, recess, partially winds along the (outer) module housing wall in the circumferential direction and in the axial direction.

[0021] Preferably, the helical segment may have at least one, preferably concave, grooved recess, which is surrounded on both sides by adjacent, preferably convex ridges, wherein the grooved recess forms a curve that winds around the outer periphery of the module housing with a preferably constant pitch. Such grooved recesses are preferably constructed as helices in the (outer) module housing wall. Accordingly, the helical segment may have at least one helix or helical structure, particularly in the form of a grooved recess in the (outer) module housing wall. Preferably, at least the region of the module housing wall including the helical segment is designed to be cylindrical. Preferably, at least one spirally constructed segment may be formed in the cylindrical circumferential surface of the module housing. The groove-like recess is synonymously referred to as a "rille".

[0022] The spirally constructed segment may include at least one rille extending over at least a portion of the outer periphery of the module housing.

[0023] Preferably, the spirally constructed segment may have at least one continuously constructed rille that completely, preferably twice or more, surrounds the module housing externally at least once. The individual loops of the rille are preferably separated from each other by, for example, a convex ridge.

[0024] Preferably, the spirally constructed segment may be configured such that the starting region of a rille and the end region of the same rille are offset from each other with respect to the longitudinal direction of the actuator module and / or the module housing.

[0025] This means that...Unlike the folded bladders known in practice (which have bulges or recesses wound at the same height or position along the axial direction in an azimuthal manner (without pitch or orientation relative to the axial direction)), the corrugated profile of the convex bulges and the alternating concave recesses between the bulges in the axial direction extends not only in the circumferential or azimuthal direction perpendicular to the axial direction, but also simultaneously in the circumferential direction and in the axial direction of the module housing, especially the module housing wall. Uniformly cooling such a folded bladder with azimuthally extending grooves (which alternate with azimuthally oriented bulges in the axial direction, i.e., their cylindrical surfaces have a meandering surface orientation) poses a challenge, and the problem is that, in order to achieve uniform cooling over the entire axial length, i.e., over all the grooves and bulges, the targeted introduction and extraction of the cooling medium must be applied to each individual groove or meandering recess (see page 3 / 21 of the specification, 6 CN 121444644 ​​A). To ensure truly uniform circulation of all the grooves or recesses, rather than leaving uncooled portions in the worst case, so-called throttling orifices are additionally introduced. However, such throttling orifices have the disadvantage that they increase flow resistance, thus requiring, in part, greater pressure compared to the case without throttling orifices. Additionally, achieving the “single-groove cooling” required to date is mechanically complex because very small (nozzle) orifices are needed as throttling sections, and to supply the cooling medium, a large volume must be introduced and discharged via very long axial orifices through the housing along the folded bladder. This is also a cost factor, as very long orifices are difficult to mass-produce, and this, combined with many small transverse orifices as (nozzle) orifices, also presents a certain manufacturing risk (e.g., broken drill bits, etc.).

[0026] The alternating ridges and recesses of the module housing wall of the present invention preferably extend around the module housing wall, particularly around the circumference of the module housing, with a constant pitch, partly in the azimuth direction and axial direction, i.e., generally spirally. Therefore, the flow resistance is significantly lower because the cooling medium flows constantly and uniformly along the spiral, making it possible to achieve high flow velocities at lower pressures, which are important for effective cooling. Furthermore, no throttling orifice is required. In the simplest case (with a bellows having a continuous spiral shape, which will be further explained below, essentially from one end region axially to the other opposite end region), one inlet and one outlet are sufficient, at which the cooling medium can enter at one point (e.g., at one end region of the spiral) and exit at another point (e.g., at the opposite end region of the spiral) after traversing the entire spiral, thereby allowing for uniform and very efficient cooling of the entire spiral.

[0027] Advantageously,The reliability of piezoelectric actuators can be improved by utilizing the actuator module according to the invention, because the piezoelectric actuator is effectively protected during operation from harmful environmental influences, especially from (air) moisture, by a tightly sealed module housing. Furthermore, by combining with the potting compound within the module housing cavity, between the piezoelectric actuator and the module housing wall, not only is the module housing wall electrically insulated from the piezoelectric actuator, but heat is also effectively transferred from the piezoelectric actuator to the module housing wall, and from there, by means of the helical corrugated profile of at least one section of the corrugated bladder of the module housing wall, is particularly effectively discharged through the circulation of a cooling medium (as will be mentioned further below). Therefore, overheating of the piezoelectric actuator can be reliably prevented. This, in turn, can advantageously affect the service life of the piezoelectric actuator itself, thus requiring less replacement of the piezoelectric actuator or actuator module. On the other hand, particularly high metering accuracy can be achieved by using the actuator module in the metering system, because thermally induced length changes in at least one piezoelectric actuator are minimized. This also improves the efficiency of the metering system, as the piezoelectric actuator is protected from overheating during continuous operation, thus avoiding interruptions in metering operation due to critical piezoelectric actuator temperatures.

[0028] Further advantageously, the actuator module according to the invention is also suitable for applications requiring particularly high clock frequencies of the piezoelectric actuator, because the heat loss is efficiently dissipated from the piezoelectric actuator surface to the module housing wall through the filling material in the module housing cavity between the piezoelectric actuator and the module housing wall, and the heat is efficiently discharged to the surrounding environment through the spirally constructed sections of the corrugated profile of the module housing wall. Therefore, the actuator module can be advantageously used in injection valves with very high clock frequencies, for example, up to 2 kHz, which is equivalent to at least double the clock frequency of conventional injection valves, and this cannot be easily achieved using known actuator modules. In addition, the actuator module can also be advantageously used in injection valves operating at clock frequencies of 3 kHz or 4 kHz.

[0029] The metering system for metering materials according to the invention includes a nozzle for discharging the metered material, a supply channel for metering the material, a discharge element, and at least one actuator module previously described and coupled to the discharge element. For discharging the metered material, the actuator module can cooperate with the discharge element and / or the nozzle during operation.

[0030] Furthermore, the metering system includes a system housing, hereinafter simply referred to as the "housing," which has at least one cylindrical recess in a housing section otherwise made of, for example, solid material, into which the actuator module is preferably precisely fitted during metering operation. Preferably,The actuator module can be tensioned on the head side by a tension spring in the housing and on the front side relative to a drive lever, which in turn can be tensioned particularly relative to the discharge element. "Precisely matched" should be understood as the internal dimensions of the recess and / or the external dimensions of the actuator module being precisely selected or determined such that there is as little free space as possible between the two components. That is, the actuator module is preferably precisely matched, even with a small gap, into the metering system so that the actuator module can still expand within the recess during operation, and the bellows will not become stuck in the recess of the housing. In particular, the actuator module and / or the cylindrical recess can be configured and / or coordinated such that the cooling medium supplied to the (corresponding) slot is largely guided through the slot by the combined action of the bulge defining the slot and the housing wall of the recess; that is, at least a large portion of the supplied volume passes through the slot, and only a small portion, preferably less than 10%, of the cooling medium overflows or skips the bulge defining the slot substantially perpendicular to its extension direction.

[0031] To completely avoid overflow or skipping caused by the small gap between the bulge of the bellows and the recess of the metering system housing, the actuator module is preferably provided with a flexible outer sleeve for metering operation, which is particularly preferably precisely fitted onto or around the actuator module, or in other words, surrounds the actuator module by means of the outer sleeve. This outer sleeve may include at least two openings in its material surface, i.e., an inlet and an outlet, i.e., at least two holes are provided. Furthermore, the outer sleeve can surround the actuator module in the metering system during metering operation. Cooling medium can enter through the openings into the grooves of the actuator module covered by the outer sleeve, i.e., radially externally encased, and then exit at the ends of the grooves.

[0032] The outer sleeve is, for example, an elastic, stretchable (expandable) rubber sleeve or the like that is heat-resistant with respect to normal operating temperatures, which can elastically yield to a certain expansion movement of the actuator module.

[0033] Preferably, the outer casing can form a radially outward, surroundingly sealed, tight seal relative to the surrounding housing of the actuator module bellows. This particularly enables the housing recesses themselves to not necessarily provide the necessary seal by forcibly constructing the recesses so narrow or fitted that the actuator module just fits into the recess. Conversely, the recesses in the metering system housing can therefore also be implemented with a small gap relative to the actuator module.

[0034] Particularly preferably, the supply hoses, i.e., the inlet hose and outlet hose, can be connected to the inlet and outlet of the outer casing. For example, they can be vulcanized together directly during the manufacture and / or installation of the outer casing. By using relatively long supply hoses (which, for example, extend from the recesses of the housing), holes for supplying and discharging the cooling medium, which would otherwise open into the recesses of the housing, can also be omitted, for example.

[0035] When there are multiple cylindrical recesses in the metering system,Preferably, each recess houses an actuator module. When metering is required at a particularly high clock frequency, multiple actuator modules may be provided, for example.

[0036] Here, for cooling, especially the actuator modules, the housing of the metering system has at least one inlet into the recess for introducing the cooling medium into at least one slot on the outside of the bellows. Furthermore, the housing of the metering system has at least one outlet from the recess for discharging the cooling medium from at least one slot. After the cooling medium is introduced into the slot at a first location with respect to the axial direction or along the corrugated profile, it is then discharged again at a slightly later location or at another location along the corrugated profile, preferably from the same slot. However, in a corresponding design of the bellows, it may also be discharged from another slot, as will be further explained below. The inlet and outlet are the actual openings, i.e., the entry or exit points, where the cooling medium is introduced into or drawn out of the slot on the outside of the bellows.

[0037] Liquid and / or gaseous media are suitable as the cooling medium, with those having a high heat capacity being preferred. As per page 5 / 21 of the specification, CN 121444644 ​​A, the cooling medium can be, for example, a gas, such as helium. Air is preferred as the cooling medium. Gases, especially air, have the advantage that the circulated components are not contaminated, but cleaning is not necessary even in the event of a possible leak.

[0038] Particularly preferably, compressed and (actively) cooled air can be used as the cooling medium because it can be provided at a relatively low cost and can be blown into the groove of the bellows through an inlet. For example, at least one vortex tube can be implemented as a cooling source to cool the cooling medium to a specific (target) temperature. Therefore, the cooling medium used in the metering system can operate at the maximum metering frequency even under adverse environmental conditions, such as particularly high ambient temperatures, while simultaneously ensuring high metering accuracy.

[0039] However, as an alternative or supplementary option, the cooling medium can also be a liquid, such as water, alcohol, or oil.

[0040] In operation, as mentioned, the bellows is inserted into a preferably precisely matched cylindrical recess. The recess can be, for example, a hole in the metering system housing. By introducing the cooling medium into the intermediate space between the bellows and the recess—that is,, in the case of a precisely matched recess, introducing it (as completely as possible) into a groove or recess in the outer contour of the bellows that winds around the bellows in a threaded or spiral shape—the cooling medium can be delivered or guided on the outside of the bellows from an inlet (e.g., at one end of the bellows) to another outlet (e.g., at the other end of the bellows). Advantageously, the cooling medium can be guided through a defined distance in both the circumferential and longitudinal directions of the actuator module via a spiral or threaded groove. Through the interaction of at least one groove in the module housing with the inlet and the associated outlet,A directional flow of cooling medium can be generated, so that specific (partial) sections of the actuator module are continuously, and particularly uniformly, surrounded by the cooling medium. Advantageously, during operation, the cooling medium can also be reliably supplied to the area of ​​the actuator module spaced apart from the inlet by means of flow guidance through the slots. Advantageously, this allows for constant and uniform cooling of the module housing wall with spiral sections. In contrast, in known encapsulated piezoelectric actuators, loading, for example, compressed air causes different areas of the piezoelectric actuator to be cooled differently.

[0041] In the metering system according to the invention, the cooling medium can continuously absorb or become heated by contacting the corrugated bladder of the module housing wall as it flows through the slot(s). During operation, the heat generated on the piezoelectric actuator inside the module housing wall is conducted outward from the piezoelectric actuator through the thermally conductive filler, preferably in a transverse or radial direction extending longitudinally with respect to the piezoelectric actuator, to the module housing wall or onto the module housing wall, and can also be directly output to the flowing cooling medium through the module housing wall to the outside of the module housing. Preferably, the module housing wall can also have high thermal conductivity. Therefore, heat can be effectively discharged or carried away in a continuous flow outside the bellows without causing overheating or heat buildup. The cooled medium, thus heated, is finally discharged or dissipated again through an outlet in the housing. Whenever desired, it can be supplied or introduced through an inlet for recooling after reaching its initial temperature again (whether by active or passive cooling), forming a cooling loop. In summary, the metering system can thus be effectively maintained below the specified maximum or maximum operating temperature during continuous operation, wherein the temperature of the encapsulated piezoelectric actuator, for example, the core temperature, is preferably up to 200°C, preferably up to 160°C, and particularly preferably up to 140°C. On the surface of the piezoelectric actuator, the temperature can preferably be up to 140°C. In addition to the components just described, the metering system may also include other components, as described later.

[0042] Advantageously, the actuator module according to the invention can be used particularly advantageously in metering systems, especially in injection valves, as previously described. In particular, by utilizing an actuator module with a spiral corrugated profile according to the invention within a packaged piezoelectric actuator housing and a matching cooling device in the metering system, the clock frequency of the metering material output can be significantly increased compared to known metering systems with conventionally packaged piezoelectric actuators, where the surface structure of the package is not spirally constructed for cooling purposes. Specification 6 / 21 pages 9 CN 121444644 ​​A

[0043] Further particularly advantageous designs and extensions of the invention derive from the dependent claims and the following description, whereby an independent claim of one claim class can also be extended similarly to dependent claims and embodiments of another claim class.Furthermore, features of different embodiments or variations can be combined to form new embodiments or variations.

[0044] Preferably, the filler material may include a base material (Grundmasse) and auxiliary materials. In particular, after hardening or curing in the module housing cavity of the module housing, the base material may here be a hardened, preferably vulcanized, and therefore elastic material. In order to manufacture the actuator module, the filler material is preferably poured into the module housing cavity between the piezoelectric actuator and the module housing wall, and the filler material then hardens in the module housing cavity after a certain period of time. For example, the components of the filler material may be provided outside the module housing, for example by mixing the base material and auxiliary materials, and then introduced into the module housing in the form of a flowable substance (filler material). In the module housing cavity, the base material may harden in order to construct an operationally ready (hardened) filler material.

[0045] At least one auxiliary material may be at least particulate, thermally conductive, and dielectric. In particular, the auxiliary material itself is a dielectric. The auxiliary material is granular, meaning it exists as a solid at least in the base material of the grout, and preferably also in the hardened grout. For example, the auxiliary material can include multiple individual auxiliary material particles, small blocks, plates, etc. A "plate" is understood as a flat element or particle of substantially uniform thickness, bounded on two opposing sides by a principally flat surface (base surface) that extends relatively far beyond its thickness. It should be noted that individual auxiliary material particles can also be approximately constructed as "plates." Correspondingly, auxiliary material particles with slightly different thicknesses within the same particle are also referred to as "plates." The base surface can have different geometries, such as approximately elliptical or circular shapes, and its outer contour can also be irregularly constructed. Accordingly, "plate-like" auxiliary material particles, also called plates, are specifically defined as having two principally planar base surfaces, where the thickness of the auxiliary material particle (corresponding to the distance between the base surfaces) is a factor less than the extension of the base surfaces.

[0046] The filler material can, in principle, include two or more different types of auxiliary materials, such as different auxiliary material particles.

[0047] The auxiliary materials are preferably arranged in the filler material in the module housing, and more preferably also in the base material in the housing, such that heat dissipation from the piezoelectric actuator, more precisely, from the piezoelectric actuator surface to the module housing wall occurs through the filler material, especially through the auxiliary materials in the filler material, during the operation of the actuator module.

[0048] Preferably, the inherent thermal conductivity of the auxiliary materials, i.e., the thermal conductivity of the auxiliary materials themselves, can be at least about 2.5 W / (m·K), preferably at least about 30 W / (m·K), preferably at least about 50 W / (m·K), and more preferably at least about 100 W / (m·K).Further preferably at least about 200 W / (m·K), particularly preferably at least about 300 W / (m·K), especially at least about 400 W / (m·K). The above values ​​preferably relate to the thermal conductivity of the auxiliary material in the form of a solid block of material, such as a solid block of auxiliary material. As is generally the case, thermal conductivity or thermal conductivity coefficient should be understood as a material property of the auxiliary material, determined based on the heat flow through the material or auxiliary material.

[0049] In particular, powdered auxiliary materials other than the filler material preferably have an (inherent) thermal conductivity of at least about 1 W / (m·K), preferably at least about 2 W / (m·K), preferably at least about 3 W / (m·K), further preferably at least about 4 W / (m·K), further preferably at least about 5 W / (m·K). The powdered auxiliary material preferably can be boron nitride and / or includes boron nitride.

[0050] The thermal conductivity of the base material (without auxiliary materials), such as silicone, is preferably at least 0.08 W / (m·K), preferably at least 0.15 W / (m·K), and especially at least 0.2 W / (m·K).

[0051] During operation of the actuator module, heat can be dissipated substantially uniformly from the piezoelectric actuator surface along the entire longitudinal extension of the piezoelectric actuator, particularly in the transverse direction, through the thermally conductive dielectric auxiliary material arranged in the base material. Preferably, the heat dissipated by the piezoelectric actuator can be transferred substantially to the peripheral surface of the module housing wall through the filler material, as will be described later. The auxiliary material, especially auxiliary material particles or auxiliary material plates, can preferably be arranged such that the longitudinal extension of the corresponding auxiliary material particles or auxiliary material plates is transverse to, and preferably substantially orthogonal to, the longitudinal extension direction of the piezoelectric actuator in the module housing. Particularly preferably, the auxiliary material particles or auxiliary material plates can be arranged in the filler material such that their longitudinal extension corresponds to the shortest distance between the piezoelectric actuator surface and the module housing wall.

[0052] The longitudinal extension (longitudinal extension) of the piezoelectric actuator is understood as the maximum or longest extension (extension) of the piezoelectric actuator in one direction. The longitudinal extension of the piezoelectric actuator is preferably parallel to the axial direction of the module housing. The longitudinal extension (longitudinal extension) of the auxiliary material plates is understood as the maximum or longest extension (extension) of the auxiliary material plates in one direction, particularly along at least one base surface of the auxiliary material plates.

[0053] Advantageously, particularly effective heat dissipation during operation can be achieved through the special arrangement of the auxiliary material plates in the base material or filler material relative to the piezoelectric actuator. In the piezoelectric actuator, due to the layered structure, thermal radiation during operation generally occurs mostly outward in the lateral or radial direction. This means that the heat loss with respect to the longitudinal extension of the piezoelectric actuator is mainly dissipated laterally away from the piezoelectric actuator surface.Almost no heat is dissipated in the axial direction, for example, towards the front or end of the actuator. Therefore, it is particularly effective in encapsulated piezoelectric actuators that at least most of the dissipated heat can be carried away from the piezoelectric actuator laterally or radially through the auxiliary material plates in the base material, especially since the lateral regions of the piezoelectric actuator constitute a relatively large portion of the entire surface of the piezoelectric actuator.

[0054] In conjunction with the above features, particularly those related to at least one helical segment of the corrugated profile of the module housing wall, the heat introduced into the module housing wall by the piezoelectric actuator during operation can be effectively removed from the metering system by the actuator module, and thus the overall heat removal is further improved.

[0055] Preferably, to provide a hardened or curable material, the base material of the potting mix may preferably include silicone resin, especially silicone. Silicone preferably includes at least one basic silicone resin and a crosslinking agent. The base silicone resin can be, for example, a silicone resin of type SG 75L2-30, wherein type SG 79L5-30 (manufacturer Elantas, Germany) can be used as a crosslinker or "cross-linker". Alternatively, at least one polyurethane or other suitable silicone resin can be used instead of silicone resin, wherein the basic components of the base material preferably have at least the above-mentioned insulation and thermal conductivity values.

[0056] The auxiliary material can preferably be boron nitride (BN). Particularly preferably, the auxiliary material can be hexagonal boron nitride (α-boron nitride). Hexagonal boron nitride (α-BN, hexagonal) consists of layers of planar hexagonal honeycomb structure, wherein B atoms and N atoms alternate, and are generally known thereafter. Particularly preferably, boron nitride can be present as an auxiliary material in powder form with a significant crystalline structure before processing. In particular, boron nitride can be present in the form of small plate-like single crystals before processing and / or in the hardened base material. Particularly preferably, each (BN) single crystal can constitute an auxiliary material particle or an auxiliary material plate. In particular, the combination of boron nitride and the curable base material is responsible for particularly effective heat dissipation, for example, when the combination is cast together into the inner cavity of the module housing, and the boron nitride is appropriately oriented or directed along its longitudinal extension toward the nearest module housing wall section before the silicone resin hardens.

[0057] Preferably, the helical sections may begin at a distance, i.e., spaced apart, from the respective end sides of the module housing in the axial direction, and from there extend at least segmentally in the axial direction toward the other end side, particularly toward the opposite end side. Particularly preferably, the respective helical sections may extend at least to the center of the bellows (with respect to the axial direction of the module housing). Preferably, the first end side of the module housing may include the base surface of the columnar module housing, particularly as formed therefrom on page 8 / 21 of the specification, CN 121444644 ​​A. Preferably,The second end side of the module housing may include the opposite top surface of the cylindrical module housing, particularly formed therefrom.

[0058] Preferably, the module housing wall of the module housing may have flat or smooth, i.e., free-ending sections in the corresponding end regions adjacent to the corresponding end sides and in the end sides adjacent to the helical sections. That is, the bellows is segmentally free-ending, or constructed as free-ending, i.e., smooth, in the regions near the axial end sides of the module housing at both ends. Therefore, the inlet and outlet in the recess of the metering system can be arranged at any azimuth angle or contact surface relative to the bellows before the end sections or end regions of the bellows. Therefore, the precise orientation of the bellows, i.e., how it is rotatably positioned in the recess about its axis of rotation in the metering system, can normally be less important, i.e., the bellows can be rotatably arranged in the recess of the metering system housing about its longitudinal axis, provided that its electrical interface is not pre-defined with a special orientation.

[0059] There are different possibilities for the shape and design of the corrugated profile or helix. In principle, the bellows can, for example, have a continuous helix (in other words, a cylindrical helix or thread), i.e., a right-hand or left-hand thread, or a counterclockwise or clockwise helix, continuously extending substantially along its entire longitudinal length. Preferably, the helical section can include at least one threaded helix. The threaded helix is ​​preferably formed through the shell wall.

[0060] Preferably, the bellows can have at least two opposing helical sections in the axial direction. For example, the bellows can have two helical sections, each with a groove, wherein the grooves are configured to be opposite to each other. Here, "opposite" means that these sections, such as the grooves, have different winding directions, sometimes also referred to as the coiling direction or helical direction. In the case of two opposing helical sections, one section has a right-hand thread and the other section has a corresponding left-hand thread. Preferably, the bellows can have two threaded helices with different helical directions.

[0061] In the installed state of the actuator module in the metering system, this allows the cooling medium to be delivered in equal proportion to these ends of the bellows via the helix of the bellows, particularly if the inlet for the cooling medium is allocated to the middle region of the bellows, where virtually half of the generated heat can be diverted. Therefore, it is particularly advantageous to load the actuator module with freshly cooled cooling medium, having, for example, a (target) initial temperature, at the point where the piezoelectric actuator typically heats up most severely, i.e., at half its length, i.e., in the middle, and thus the actuator module is cooled particularly intensely there, where…The cooling power at both ends (where the piezoelectric actuator is typically also heated less intensely) decreases slightly if necessary. This bellows therefore ideally matches the heat dissipation profile, or loss heat profile, of the piezoelectric actuator.

[0062] However, unrelatedly, the two helical sections with opposite winding directions have another advantage. That is, they prevent the bellows from becoming undesirably torsion, deformed, or twisted over time during operation due to torsional forces caused by the continuous corrugated profile constructed along the winding direction under high operating loads, thus making accurate metering operation impossible. In the presence of two opposing sections, half the torque is generated in each of the two sections compared to a continuous or uniform section. However, the two torques generated do not add up to the total torque described above, but rather cancel each other out at least largely or completely due to the opposite winding directions and the associated opposite directions of action or rotation.

[0063] Preferably, particularly preferred, at least two helical sections with opposite winding directions are separated from each other. In this case, the cooling medium can be discharged again from another slot instead of the slot from which it was initially introduced. That is, the introduction can be made into the first slot, which is separated from or interrupted by the second slot through a slotless circumferential section, and the cooling medium is then discharged from the second slot.

[0064] Preferably, at least two preferably independent helical sections can be separated from each other by a flat or smooth section. The flat section is preferably formed by the module housing wall. In principle, the two helical sections can have the same winding direction. However, it is preferred that the two helical sections have opposite winding directions. Accordingly, the two helical sections can preferably each have a threaded helix with different helical directions.

[0065] Preferably, the helical sections can start from the flat section and extend axially to the end or end side of the module housing. This can be advantageous if multiple inlets and / or outlets are provided in the housing of the metering system.

[0066] Particularly preferably, a flat section can be arranged in the middle of the bellows, and two spiral sections can extend outward from there to the two opposite ends of the bellows, particularly towards one end of the module housing. Here, the cooling medium can be introduced, for example, at both ends, for example near the end sides, through inlets, and discharged in the middle through outlets, or preferably the opposite, i.e., the cooling medium enters the recess in the metering system at the middle height of the bellows, and is discharged or discharged at the two end heights of the bellows.

[0067] In order to achieve a reliable seal between the outer surface of the bellows and the inner surface of the recess in the metering system housing (e.g.,If the components are not precisely matched or coordinated or supported, an annular sealing element, such as an O-ring, can be arranged in the region at at least one end of the bellows. If each of the respective ends of the bellows has such a sealing element, the cooling medium, after entering the region between or within the sealing elements, is in any case retained in that region, thus eliminating the risk of the cooling medium reaching other regions of the metering system, i.e., undesirably flowing out of the housing above, for example, along the recess at the wall or at the bellows, or—undesirably—undesirably entering the region of the lever and / or discharge element below.

[0068] The corresponding sealing element contact section on the inner surface of the recess can preferably be directly adjacent to the inlet and / or outlet, on which the corresponding sealing element seals by contacting the bellows radially inward and the recess radially outward. This has the advantage that no dead point is formed on the sealing element itself, where cooling medium might otherwise accumulate or gather when it enters or exits slightly away from the dead point.

[0069] Different possibilities exist for the corrugated profile, especially for the configuration of bulges and recesses, such as grooved recesses.

[0070] Preferably, at least one of the helical sections of the bellows may have a pitch of preferably at least 1 mm, particularly preferably at least 5 mm, and very particularly preferably at least 10 mm.

[0071] Alternatively or additionally, at least one of the helical sections of the bellows may have a pitch of preferably at most 35 mm, preferably at most 20 mm, and particularly preferably at most 15 mm. Preferably, at least one groove of the helical section may have the above-mentioned pitch. The term "pitch" here has the same meaning as the pitch used and described accordingly in screw threads.

[0072] Different possibilities also exist for the design of the metering system, especially the recess.

[0073] Preferably, the recess of the metering system may have at least one radial inlet.

[0074] Alternatively or additionally, the recess of the metering system may have at least one radial outlet. The respective inlets or outlets may be arranged radially in the housing relative to the cylindrical recess. Preferably, each radial inlet or outlet can be constructed substantially orthogonal to the longitudinal extension or longitudinal direction of the mounted housing module, particularly transverse to the axial direction of the housing module.

[0075] In an actuator module with a module housing mounted in a metering system, the radial inlets and / or radial outlets can be particularly preferably located substantially at the height of the upper end section of the module housing. The upper end section can preferably be opposite to the discharge direction of the metering material from the metering system.

[0076] Alternatively or additionally, the radial inlets and / or radial outlets can be located at the height of the lower end section of the module housing. Preferably, the lower end section can be oriented towards the discharge direction of the metering material from the metering system.

[0077] Preferably, at least one of the walls can have an inlet or outlet.The at least one wall axially defines, i.e., at least partially axially defines the housing recess as described on page 10 / 21 of the specification, CN 121444644 ​​A. The axial definition of the housing preferably relates to the axial direction of the inserted module housing, that is, to a definition toward the end side of the module housing.

[0078] Alternatively, one of the walls axially defining the housing recess may preferably have an inlet, and the opposite wall may have an outlet. Thus, cooling medium may be introduced into the groove of the bellows in an axial direction, for example, generally parallel to the longitudinal extension of the module housing, in a region near one axial end side or end face of the module housing, and guided out from the groove of the bellows in a region near the other opposite axial end side or end face of the module housing. This implementation has a particular advantage that the entire cooling device with the input and output sections of the cooling medium can be installed in the structural space of the actuator module cross-section, that is, on the axial extension of the piezoelectric actuator, and thus the corresponding metering system or metering valve can be implemented very space-efficiently. This is a significant advantage in parallel applications, i.e., in the case of metering devices with multiple parallel metering systems, because the metering systems can be arranged closely side by side and the nozzles are thus placed very close to each other.

[0079] In this respect, it should be noted that the recess can also be designed to be radially (at least in certain sections) widened around the end section of the bellows, so that the cooling medium can be introduced from the axial direction next to the end section of the bellows through the widened section(one or more) of the recess into the groove on the outside of the bellows, as will be explained in more detail below based on exemplary embodiments.

[0080] Preferably, when the actuator module is installed as specified, the recess can be centrally located in the metering system, i.e., viewed along the axial direction of the module housing on the intermediate plane, with an inlet in the radial wall between the end sides of the actuator module housing for introducing cooling medium, for example, into the recess from the radial direction. Preferably, the cooling medium can be introduced in such a way that the cooling medium is applied to the surface of the bellows. The radial wall of the recess preferably extends toward the bellows and / or parallel to the longitudinal direction of the module housing.

[0081] Preferably, in a metering system with a transmission mechanism, an outlet can be provided in the region of the transmission mechanism, which is located in another recess between the piezoelectric actuator and the discharge element. The outlet in the region of the transmission mechanism enables through-flow or circulation of components of the transmission mechanism, such as transmission levers, so that debris that may be generated during operation can be directly removed, and the components can be cooled at least slightly at the same time.

[0082] Alternatively or additionally, an outlet can be provided in the region of the discharge element. This additionally achieves cooling and cleaning of at least a portion of the discharge element.

[0083] Alternatively or additionally,At least one inlet can be constructed in the axial end region of the bellows, preferably in the region, for example, the upper side of the module housing, for introducing the cooling medium, which enables a very space-saving design for the metering system. Furthermore, in this way, the entire actuator module can be cooled from one end of the bellows, particularly from one end of the module housing, all the way to the drive mechanism in the discharge element region, and, as already mentioned, material debris generated during operation can be blown or flushed out of the drive mechanism. Here, if the cooling medium is subsequently to be reused after cooling, it can be appropriately reprocessed, cleaned, or filtered, which is considered desirable in terms of sustainability.

[0084] Particularly preferably, the inlet can be formed in the axial end region of the bellows for introducing the cooling medium in the axial direction. This allows for a particularly compact assembly consisting of the housing, the cooling medium supply device, and the actuator module, as no side supply holes and / or interfaces are required, thereby reducing the lateral structural space requirements of the metering system. This is particularly advantageous when a high arrangement density of multiple closely spaced metering systems is required or desired. Preferably, the flow direction of the cooling medium can be parallel to the longitudinal direction of the module housing. For example, the axially extending hole can be constructed on the actuator module as a recess on the upper edge of the module housing or as a notch through the module housing cover, along the outer side of the module housing wall relative to the bellows (see page 11 / 21 of the specification, CN 121444644 ​​A).

[0085] Particularly preferred for metering systems having an inlet in the end region of the bellows on the piezoelectric actuator end side is that the housing preferably has an additional, particularly preferred, recess extending transversely to the front side of the piezoelectric actuator. The additional recess can, for example, be connected to the piezoelectric actuator and / or to the recess for the actuator module along the discharge direction (of the metering material). Here, a transmission lever can be arranged in the additional recess, which transmits the longitudinal extension of the piezoelectric actuator, especially the change in longitudinal extension, to the discharge element of the elastically supported push rod device via the lever arm of the transmission lever. The transmission lever can, for example, be asymmetrical.

[0086] The push rod device typically extends into the nozzle of the fluid unit of the metering system as a discharge element, which is supplied with the metering medium through the fluid unit.

[0087] Here, the outlet for the cooling medium can preferably be located in the region of another recess, close to the push rod device of the elastic support. Therefore, the cooling medium introduced at the piezoelectric actuator end side at the housing inlet in the end region of the bellows, for example in the region opposite to the discharge direction, can flow through and cool the entire metering system, especially the actuator module, including the other recess. Brief Description of the Drawings

[0088] The invention will be further described again below with reference to the accompanying drawings and embodiments. Here, in different drawings,The same components are given the same reference numerals. The drawings are to be understood herein as schematic only and are not to scale. The drawings are shown.

[0089] FIG1 shows a rough schematic cross-sectional view of an embodiment of a metering system according to the invention, equipped with an actuator module according to the invention.

[0090] FIG2 shows a rough schematic cross-sectional view of the metering system of FIG1 along section line A-A.

[0091] FIG3 shows a separate side view of the actuator module in FIG1 and FIG2.

[0092] FIG4 shows a rough schematic cross-sectional view of a portion of the metering system of FIG2, wherein the actuator module is a slightly modified variant, along a similar section line Á-Á through the metering system.

[0093] FIG5 shows a separate side view of the actuator module of FIG4, slightly modified relative to the actuator module of FIG3.

[0094] FIG6 shows a rough schematic cross-sectional view of a portion of an embodiment of a metering system according to the invention, having an actuator module according to the invention, along a similar section line Á-Á through the metering system.

[0095] FIG. 7 shows a separate side view of the actuator module of FIG. 6.

[0096] FIG. 8 shows a rough schematic cross-sectional view of a variant of the metering system of FIG. 6, which matches a slightly modified variant of the installed actuator module, passing through the metering system along a similar section line Á'́ - Á'́.

[0097] FIG. 9 shows a separate side view of the actuator module of FIG. 8, slightly modified relative to the actuator module of FIG. 6.

[0098] FIG. 10 shows a portion of an embodiment of the metering system according to the invention, having the actuator module of FIG. 4, passing through the metering system along a similar section line Á'́ - Á'́.

[0099] FIG. 11 shows a separate side view of the actuator module, slightly modified relative to the actuator module of FIG. 10.

[0100] FIG12 shows a rough schematic cross-sectional view of another actuator module, which is encased in a stretchable sealing jacket, which includes a supply hose and an outlet hose for the cooling medium.

[0101] FIG13 shows a rough schematic cross-sectional view of the actuator module of FIG12, this time with an jacket without the supply hose and outlet hose. Specification 12 / 21 pages 15 CN 121444644 ​​A Detailed Description

[0102] As described above, the above-described actuator module can be used, for example, in a metering system for metering liquid to viscous metering materials, such as in an injection valve shown schematically and in cross-section in FIG2. Since the basic structure of such an injection valve is known, only the main components are described below.

[0103] The metering system 50 is shown in cross-section in FIG1 and in longitudinal section in FIG2.The metering system 50 includes an actuator assembly 51 as a basic component and a fluid assembly 52 detachably coupled thereto, wherein the coupling is exemplarily performed here via two screws 62. The actuator assembly 51 essentially includes all the components of the discharge element 53a or push rod 53a for driving or moving the push rod device 53 of the fluid assembly 52 within the nozzle 54.

[0104] In addition to the nozzle 54 and the supply channel 56 for metering material D to the nozzle 54, the fluid assembly 52 also includes all other components that are in direct contact with the metering material D, and further includes elements necessary for mounting together or holding the relevant components in contact with the metering material D or metering medium D in their position on the fluid assembly 52.

[0105] In the embodiment of the metering system 50 shown in FIG. 2 (and in other embodiments shown), the actuator assembly 51 includes a housing 57, more precisely a housing block 57 having two internal chambers 58, 59, namely, on the one hand, an actuator chamber 58 having an actuator module 1 located therein, the actuator module having at least one piezoelectric ceramic actuator 2 (FIG. 2) tightly encapsulated in a module housing 3, and on the other hand, an actuation chamber 59 into which a movable discharge element 53a (here, a push rod 53a) of the fluid assembly 52 extends. By means of a transmission mechanism 60 including a lever 63 (which extends substantially horizontally from the region in the actuation chamber 59 located below the actuator chamber 58 to the region in the actuation chamber 59 located above the push rod device 53), the push rod 53a is operated by the actuator module 1 so that the metering material D to be metered is discharged by the fluid assembly 52 at a desired time and in a desired amount through the nozzle 54 in the discharge direction AR. The push rod 53a closes the nozzle opening 55 and thus also serves as a sealing element 53a. However, since most of the medium is first discharged from the nozzle opening 54 by the push rod 53a when the push rod 53a moves toward the nozzle opening 55 in the discharge direction AR, it is referred to here as the discharge element 53a.

[0106] In order to control the piezoelectric actuator 2 (FIG. 2), the actuator module 1 is electrically or signal-technically connected to the control device 5, which may, for example, be designed as part of the metering system 50. The connection to the control device 5 is made by a connecting cable 5́, which is connected at its end to the actuator module control interface 7a, for example, a suitable plug 7a.

[0107] The actuator module control interface 7a respectively contacts the electrical interface 6a in the module housing 3, which are two contact pins 6a, which pass through the module housing wall 3w of the module housing 3 in a tightly sealed and electrically insulating manner. In FIG. 1, the actuator module 1 includes a total of four contact pins 6a, 6b.The contact pins are disposed in the end side 12 or end side 12 (also called the module housing cover) of the module housing 3 (see FIG. 3). Two contact pins 6a located externally here are used to control the piezoelectric actuator 2 or for communication between the piezoelectric actuator 2 and the control device 5.

[0108] Two contact pins 6b shown in the middle here are used to transmit the measured values ​​of the temperature sensor from the module housing 3 to the control device 5. For this purpose, the contact pins 6b are connected to the control device 5 on the one hand via the temperature sensor interface 7b, via the connecting cable 5, and on the other hand in the module housing 3 to the respective temperature sensors (not shown here). For example, the measured values ​​of multiple temperature sensors can also be forwarded to the control device 5 in a position-resolved manner via the contact pins 6b.

[0109] The piezoelectric actuator 2 (FIG. 2) (and thus the module housing 3) arranged in the module housing 3 can expand (expand) and contract again in the longitudinal direction of the actuator chamber 58 according to the activation of the control device 5. Actuator module 1 can be inserted from above into actuator chamber 58 and supported therein in a height-adjustable manner, allowing for precise adjustment of actuator module 1 relative to the motion mechanism having transmission mechanism 60. In the case shown here, the module housing cover or end side 12 (FIG. 3) is internally supported on actuator chamber 58 by a support element (not shown in detail), which serves as an upper support here and can be adjusted, for example, by a helical motion (not shown) to adjust actuator module 1. Accordingly, actuator module 1 is supported downward on lever 63 by a downwardly contracting pressure member 64, which is placed on lever support 65. Through lever support 65, lever 63 can tilt about tilting axis K, such that lever arm of lever 63 extends through actuation chamber 59. At the end of the lever arm, the lever arm has a contact surface 66 facing the push rod 53a of the fluid assembly 52 coupled to the actuator assembly 51, which presses against the contact surface 67 of the push rod head 68.

[0110] In all the embodiments shown, the push rod head 68 is pressed against the lever 63 from below by the push rod spring 69, such that the contact surface 66 of the lever 63 is in constant contact with the contact surface 67 of the push rod head 68. However, in principle, a gap may also exist between the push rod 53a and the lever 63 at the initial or rest position of the push rod spring 69. To achieve a nearly constant preload of the drive system, the lever 63 is hereby pushed upward at its end in contact with the push rod 53a by the actuator spring 70.

[0111] The push rod 53a is supported on the push rod support 71 by means of the push rod spring 69, and the push rod seal 72 is connected downward to the push rod support. The push rod spring 69 presses the push rod head 68 upward in the axial direction away from the push rod support 71. Therefore,The push rod tip 73 is also pressed away from the sealing seat 74 of the nozzle 54. That is, the nozzle opening 55 is not closed in the static state (unexpanded state) of the piezoelectric actuator 2 (FIG. 2) when no external pressure is applied to the push rod head 68 from above.

[0112] Metering material D is supplied to the nozzle 54 via the nozzle chamber 75 and the supply channel 56 connected thereto, which can be connected to the metering material reservoir (not shown here) by means of the metering material supply pipe 76.

[0113] The metering system 50, or more specifically the housing block 57, also includes (as exemplarily and schematically shown at different locations in the metering system 50 in FIG. 2, 4, 6, 8 and 10) inlets 58irad, 58iax and outlets 58orad, 59o of a controllable cooling device, which have direct or indirect connections to the bellows 10, 20, 30, 40 of the actuator module 1. Cooling medium M, such as air M, especially compressed air or pre-cooled compressed air, can be introduced from the outside into the actuator chamber 58 at a desired location through respective inlets 58irad and 58iax.

[0114] As shown in FIG2, cooling medium M flows into actuator chamber 58 via radial inlet 58irad, which is substantially arranged at height he of the upper end section of the bellows 10 of actuator module 1. Thus, cooling medium M flows into actuator chamber 58 in the region between the upper end side 12 and the lower end side 11 (FIG. 3) of module housing 3 here, and first encounters bellows 10 (FIG. 2) at height he. Due to the helical structure of housing wall 3w, the inflowing cooling medium M is guided along the outer peripheral surface of bellows 10 through the groove 17 defined by two protrusions 18, and flows selectively around the peripheral surface in the helical region. As can be seen, each protrusion 18 is substantially flush with the wall 58w or inner circumferential surface 58w of the actuator chamber 58 of the metering system 50. This allows the cooling medium M to flow directionally along the groove 17. Through contact with the circumferential surface of the bellows 10, the cooling medium M absorbs heat and directs it away from the actuator module 1. This heat is generated in or applied to the piezoelectric actuator 2 during operation and is guided to the module housing wall 3w, or the circumferential surface of the bellows 10, via the filling material 4 in the inner cavity 3i of the module housing, particularly via the auxiliary material 4b (Fig. 2) in the base material 4a. This allows for efficient cooling of the bellows 10. After the cooling medium M has completely passed the circumferential surface of the bellows 10 along the groove 17,The cooling medium M is discharged, blown out, or drawn out again from the actuator chamber 58 through the radial outlet 58orad. The outlet 58orad is located at a height hf of the lower end section of the bellows 10 of the module housing 3. The flow direction of the cooling medium M through the metering system 50 is schematically shown by means of arrows. Furthermore, the orientation of the radial inlet 58irad and the radial outlet 58orad relative to the axial direction RAX and the radial direction RRAD of the module housing 3 or the actuator module 1 is shown in FIG2 by means of a schematic coordinate system. In the cross section of FIG1, the axial direction RAX extending upward is schematically shown as the center point of the actuator module 1, with the radial direction RRAD extending laterally relative to it. The azimuth direction RAZ is also schematically shown in FIG1. ​​

[0115] The heated cooling medium M flowing out of the actuator chamber 58 can be supplied to the cooling device to cool down when needed, so that it can then be used for re-cooling via the inlet 58irad. As an alternative to compressed air cooling, see page 14 / 21 of document 17 CN 121444644 ​​A, which shows a circulation loop of a heat exchanger for outputting absorbed heat, wherein the compressed air used is typically not subsequently utilized further.

[0116] The actuator module 1 of FIG2 is shown in detail in FIG3, wherein the bellows 10 is configured such that a single slot 17 extends continuously, or through, the entire length of the helical section 14. The helical section 14, or its starting point and end side 12, are provided with a distance a10. In the example shown here, the opposite ends of the helical section 14 facing the end side 11 form an annular ridge.

[0117] The module housing 3 in FIG. 3 is designed such that, in the installed state (FIG. 2), cooling medium M, aligned with or touching the grooved circumferential surface of the bellows 10, flows through a groove 17, which extends or winds along the bellows 10 in a spiral shape in the winding direction WRAX,AZ. The groove 17 is laterally defined by parallel ridges 18 extending on both sides of the groove 17. The groove 17 has a groove width 17b preferably of 1 mm, wherein the corresponding ridge 18 has a ridge width 18b preferably of 1 mm. In this example, the pitch 19s of the bellows 10 is correspondingly 2 mm. Furthermore, the module housing 3 includes a front annular flange 16 located here above and an end annular flange 15 located here below.

[0118] An embodiment of the actuator module 1 with a bellows 20 modified relative to FIG. 3 is shown in FIG. 4 and FIG. 5, wherein the spiral section 14 is disposed with the end side 12 located here above the module housing 3 at a distance a20. The spiral section 14 here, in the direction towards the end side 12, abuts against or transitions into the flat or unwinding section 22. Therefore, the housing 3 does not have the final annular ridge where the groove terminates (unlike in Figure 3). Instead,The groove 17 leads into the flat section 22. The advantage of this design, with its freely ending spiral section leading into the flat section 22, is that the cooling medium flow can be essentially aligned with any point along the outer periphery of the flat section 22, where the cooling medium flow itself flows into the initial groove 17.

[0119] In contrast, in the groove 17 of the bellows 10 of FIG3, defined by an annular ridge in the form of a "flange," a single (target) entry point for the cooling medium to enter the groove 17 is defined. If the cooling medium is introduced precisely at this location, it automatically flows into the groove 17 and flows along the groove 17 until the end of the spiral section 14. However, if the cooling medium is introduced into the groove 17 at a later location, a "dead" section may be formed, where the cooling medium may be intercepted or accumulate.

[0120] In the bellows 10 (see Figures 2 and 3) and the slightly modified bellows 20 (see Figures 4 and 5), it is advantageous that, as in Figures 2 and 4, the outlet 58orad is located at the opposite end section of the bellows 10, 20 as viewed in the axial direction RAX (Figure 2), opposite to the inlet 58irad, because then almost the entire bellows 10, 20 is cooled. As shown in Figures 2 and 4, in the region of the end section of the bellows 10, 20, there is an inlet 58irad at the annular flanges 16, 26 (Figures 3 and 5) close to the end side 12 of the module housing 3. In the installed state, the outlet 58orad is located in the region of the opposite end section of the bellows 10, 20, close to the annular flanges 15, 25 (Figures 3 and 5) near the front side 11 of the module housing 3 (Figures 2 and 4). Relative to the installed bellows 10, 20, two openings 58irad, 58orad respectively enter radially outward into the region of the circumferential surface section on the bellows 10, 20, and from there pass through in the radial direction RRAD of the respective bellows 10, 20 (which corresponds to the radial direction RRAD of the corresponding actuator module 1) and finally extend outward from the housing block 57 of the metering system 50 to the cooling device.

[0121] In Figures 2 and 4, the radial inlet 58irad and the radial outlet 58orad are respectively located, for example, along the azimuth direction RAZ of the bellows 10, 20 on the right side of the housing block 57.

[0122] The bellows 20 shown in Figure 4 (and also in Figure 10 in the embodiment of the metering system 50 which will be further described below) differs only slightly from the bellows 10 of Figure 3, as already described. The difference lies in the configuration of the corrugated profiles 10 and 20 in the end sections preceding the end sides 11 and 12 of the module housing 3 of the respective bellows 10 and 20. In the bellows 10, the corrugated profile 10 terminates preceding the respective annular flanges 15 and 16, wherein the groove 17 closes toward the annular seal 61 (see Figure 2), i.e., the end of the groove 17 is defined by the ridge 18. In other words,The helical section 14 of the corrugated profile 10 terminates at two opposite ends with annular raised sections as part of raised sections 18, and is thus separated from the corresponding annular flanges 15, 16 (which in the installed state of the actuator module 1 serve as a stop for annular seals 61 toward the front side 11 of the module housing 3, or annular seals 61 toward the end side 12).

[0123] Conversely, in the housing module 3 of Figures 4 and 5, in the corrugated bladder 20, the grooves 17 at the corresponding ends of the helical section 14 (shown here, for example, as having a left-handed helix or winding) freely end in wider flat sections 21, 22 to the corresponding annular seals 61 (see Figure 4), which are located immediately in front of the annular flanges 25, 26 and begin at a distance a20 above the end side 12 (Figure 5). The lower annular flange 25 in Figures 4 and 5 protrudes less than the annular flange 26 on the opposite end section. This means that the bulge 18 of the defining groove 17 ends approximately one turn earlier. Therefore, in the installed state of the bellows 20, the path to the end sides 11, 12, between the surface of the bellows 20 and the wall 58w or inner circumferential surface 58w of the actuator chamber 58, is sealed only by the annular seal 61, and not by the bulge 18 itself (Figure 4).

[0124] In another embodiment of the metering system 50 according to the invention in Figures 6 and 8, it has actuator modules 1 according to the invention with bellows 30, 40, respectively, which are installed according to the invention, and two radial outlets 58orad are respectively arranged at heights he, hf of the end sections of the bellows 30, 40. A radial inlet 58irad is arranged between the external outlets 58orad. This radial inlet is arranged at a height hm (Fig. 6) corresponding to the middle section 33 of the installed bellows 30 or at a height hm (Fig. 8) corresponding to the middle flat section 43 of the bellows 40 in the housing block 57.

[0125] The embodiment of the actuator module 1 in Figs. 6 and 8 with bellows 30, 40 shown in detail in Figs. 7 and 9 differs from the above-described embodiments (Figs. 3 and 5) in that...The corrugated profiles 30 and 40 include two separate helical segments 34l and 34r (Fig. 7) or 44l and 44r (Fig. 9) in their axial extension, instead of a continuous helical segment 14. The corresponding helical segments 34l, 34r, 44l, and 44r of the corresponding corrugated bladders 30 and 40 in Figs. 7 and 9 are approximately half the length of the continuous helical segment 14 of the corrugated bladder 10 of the actuator module 1 in Fig. 3. They extend from the intermediate segment 33 (Fig. 7) or from the flat intermediate segment 43 (Fig. 9) to the end segments of the corresponding corrugated bladders 30 and 40, respectively.

[0126] In the case of the corrugated bladder 30 in Fig. 7, the helical segment 34l with an annular ridge 18 terminates slightly in front of the end-side annular flange 35, which again serves as a stop for the annular seal 61 (see Fig. 6) near the front side of the corrugated bladder 30. Another helical segment 34r in another end region terminates slightly ahead of the front annular flange 36 near the end side 12, specifically at a distance a30 from the end side 12 of the module housing 3 of the bellows 30. In the intermediate segment 33, the two grooves 17 of the two helical segments 34, 34r meet or intersect each other precisely at one end point or dead point. The two helical segments 34l, 34r have, and therefore the corresponding grooves 17, also have different winding directions (Fig. 7).

[0127] As can be seen in Fig. 6, in the installed state of the actuator module 1, the inlet 58irad of the metering system 50 points to a division point slightly offset relative to the dead point or intersection of the two grooves 17 described according to Fig. 7, which is located approximately a quarter turn before the dead point along the azimuth direction RAZ, at which the two helical segments 34l, 34r divide into two grooves 17. By positioning the inlet 58irad and actuator module 1 relative to each other as shown in FIG. 6, the cooling medium flows into the two slots 17 in the same manner and flows along the two slots 17 toward the outlet 58orad, and here, as little cooling medium as possible flows in the opposite direction toward the endpoints or dead points of the two slots 17.

[0128] The bellows 40 in FIG. 9 includes two helical sections 44l, 44r with different winding directions, wherein the two slots 17 also have different helical directions. In this bellows 40, the helical section 44l (here, the lower one) ends at the end section of the bellows 40 into a short, flat or unwound section 41 (without a ridge), which is defined by an annular ridge extending purely in the azimuth direction RAZ, on which a positioning groove for the annular seal 61 is connected on the front side (that is, on the front-facing side of the ridge) (see FIG. 8).The positioning groove is further defined by an annular flange 45 (near the front side of the bellows 40, page 16 / 21, CN 121444644 ​​A) as a stop to the front side.

[0129] Another helical section 44r at the other end region of the bellows 40 has the same design. There, the helical section 44r transitions to a flat or unwinding section 42 at a distance a40 from the end side 12 of the module housing 3 of the bellows 40, on which an annular ridge is connected (this time at the end side), which is defined by an annular flange 46 as a stop to the end side 12 at the spacing of the annular seals 61 (FIG. 8).

[0130] At the center of the bellows 40 in FIG. 9, the two helical sections 44l, 44r are separated by the middle flat section 43, such that the sections 44l, 44r are spaced apart from each other at a distance b40. Throughout the entire spacing b40, the intermediate section 43 has no grooves or bulges. However, the spacing b40 between sections 44l and 44r can vary circumferentially along the module housing 3. As shown in FIG8, the actuator module 1 is configured in the metering system 50 such that at the height hm of the intermediate section 43, the inlet 58irad is located in the wall 58w of the actuator chamber 58 of the housing block 57 so that the cooling medium M is introduced here from the right side to the right side of the actuator chamber 58. In principle, the cooling medium M can also be introduced into the actuator chamber 58 from the other side.

[0131] By having the inlet 58irad located in the middle between the two outlets 58orad in FIG6 and FIG8, the region of the piezoelectric actuator 2 that is most intensely heated during operation (FIG2), i.e., the middle, can be cooled most intensely because the cooling medium M is introduced here in a manner that is just cooled. Towards the corresponding ends, the piezoelectric actuator 2 is also generally heated less during operation, thus requiring less and less cooling here. Therefore, although the cooling medium M becomes hot due to flowing around the bellows 30, 40 towards the end region, sufficient cooling of the piezoelectric actuator 2 can be achieved at the end. Therefore, the degree of cooling, or cooling power, can also be related to the degree of heating of the piezoelectric actuator 2, and thus to the degree of heating of the peripheral surfaces of the bellows 30, 40.

[0132] In the actuator module 1 in Figures 7 and 9, sections 34l, 44l have left-handed helical or winding directions WRAX, AZ, while sections 34r, 44r have right-handed helical or winding directions WRAX, AZ. The reverse-winding sections 34l, 34r, 44l, 44r have the advantage that they respectively halve the torsional force that may occur during the operation of the metering system, and can also directly cancel each other out by the reverse winding directions WRAX, AZ. In the case of a cylinder, that is, with the increase of radius and / or the increase of the length of the threaded section with the same winding direction, depending on the material properties and material thickness,Torsional forces can cause the cylinder to twist in certain situations. Reducing this effect through structural design expands the possibilities for material selection and thickness.

[0133] Figure 10 shows another embodiment of the metering system 50 according to the invention, wherein the cooling medium M is introduced into the metering system 50 from the axial direction, and the metering system is sufficient without, for example, the annular seal 61 described according to Figure 4 (where the annular seal is present, it here only serves a coarse adjustment function for the actuator module 1 in the housing 57). This is because, in these locations, the cooling medium M, at the end side of the bellows 20*, is surface-milled in or along the adjacent wall 58w of the recess 58* of the housing 57 of the metering system 50, and ultimately enters the groove 17 of the bellows 20* from the outside via the axial inlet 58iax next to the annular flange 26 of the bellows 20*.

[0134] An alternative variation of this is shown in Figure 11, wherein instead of the housing 57 surrounding the actuator module 1, or more precisely, the recess 58 in the housing 57 having the mentioned milled portion, the upper end section of the bellows 20* and the annular flange 26 have four, for example, drilled or milled, recessed module housing edge recesses 3a through which the cooling medium M reaches or flows into the actuator chamber 58*.

[0135] Specifically, for this purpose, for example by means of a ball end mill or drill bit, laterally milled portions in the form of concave or hemispherical cuts can be introduced in the end side 12 and / or the annular flange 26, such that the cooling medium M can enter from the inlet 58iax or supply hole through the laterally widened portions or these laterally widened portions in the wall 58w of the recess 58* into the helical or helical groove 17.

[0136] Subsequently, the cooling medium flows into or along the spiral groove 17, and then flows axially or end-side from the actuator chamber 58* next to the annular flange 25 at the opposite end section of the bellows 20 into the actuation chamber 59, which is another recess 59, in which the lever 63 of the transmission mechanism 60 is located, in particular. The construction of the transmission mechanism 60 has been described in the specification on pages 17 / 21, 20 CN 121444644 ​​A, with the aid of FIG2. The axial entry and exit of the cooling medium has a particular advantage, that is, the entire cooling device with input and exhaust air can thus be installed in the structural space of the cross-section of the actuator cooling device, and therefore the corresponding metering system or metering valve can be implemented very space-savingly, especially narrowly, which is a great advantage in applications with multiple parallel and closely arranged metering systems. In addition, the cooling medium M also flows through the actuation chamber 59 in the region of the transmission mechanism 60.Then, in the region of the push rod device 53, at the height of the actuator spring 70 or the push rod spring 69, it is laterally (to the right) through the hole in the housing block 57 via the outlet 59o, and is led out of the housing block 57, for example, into the cooling device (not shown).

[0137] The flow from the inlet 58iax on the end side 12 of the module housing 3 of the bellows 20 to the outlet 59o in the region of the transmission mechanism 60 or the push rod device 53 has the advantage that material debris and the like generated during the operation of the metering system 50 can be flushed out of the system directly together. If so, it is advantageous that the cooling medium M is filtered accordingly after each pass, at least when the cooling medium M is reused.

[0138] Now, Figures 12 and 13 also show the actuator module 1 with a hose-like, elastic or stretchable (expandable) jacket 47. The jacket 47 is pulled onto the actuator module 1 once for metering operation, or alternatively, the actuator module 1 is covered thereunder. A closed, tightly spirally extending channel is formed by a sheath in the form of a jacket 47 around the actuator module 1, defined by a groove 17 of the bellows 20** of the actuator module 1 and defined by a side ridge 18, through which the cooling medium M can be guided. The jacket 47 includes an opening at each of its two axial end regions, to which hoses 48, 49 for the cooling medium M are vulcanized. This has the advantage that the housing 57 of the metering system 50 itself does not need to contain these channels in the form of actual holes.

[0139] The jacket 47, which fits tightly on the ridge 18, prevents the cooling medium M from skipping or overflowing the ridge 18 perpendicular to the winding direction WRAX,AZ of the groove 17. Furthermore, in the installed state (in which the actuator module 1 with the jacket 47 is inserted and assembled in the metering system 50), it is no longer necessary to precisely match and almost seal the actuator module 1 through the surrounding housing 57 or the actuator chamber 58 in the housing 57. Figure 13 shows a variant of the actuator module 1 in Figure 12, but without the elongated supply hoses 48, 49. For this purpose, the corresponding holes or supply hoses are located in the housing of the metering system, although this is not explicitly shown here.

[0140] Through the combined action of the injection material 4 and the auxiliary material 4b inside the actuator module 1, and utilizing the design of the corrugated profiles 10, 20, 30, 40 on the surface of the actuator module 1 according to the invention, and the cooling medium inlet and outlet of the metering system 50, heat dissipation from the piezoelectric actuator 2 can be particularly efficient during the operation of the metering system 50, which can advantageously affect the metering accuracy and service life of the piezoelectric actuator 2.

[0141] Finally, it should be noted again that the apparatus described in detail above is merely an embodiment, which can be modified in different ways by those skilled in the art without departing from the scope of the invention. For example,It is also conceivable that the helical section of the bellows may have other pitches and / or winding directions, as shown in the embodiments, as actuator modules. Furthermore, the use of the indefinite article "a" or "an" does not preclude the possibility that the features involved may exist in multiple forms. Similarly, the terms "element" and "assembly" do not preclude the possibility that the component involved consists of multiple interacting sub-components, which may, if necessary, be spatially distributed.

[0142] List of reference numerals 1 Actuator module 2 Piezoelectric actuator / actuator 2́ Piezoelectric actuator surface 3 Module housing 3i Module housing cavity Instruction manual 18 / 21 pages 21 CN 121444644 ​​A 3w Module housing wall 3a Module housing edge recess 4 Filling material 4a Basic material / material 4b Auxiliary material 5 Control device 5́ Connecting cable 6a Interface / contact pin (piezoelectric actuator) 6b Interface / contact pin (temperature sensor) 7a Actuator module control interface 7b Temperature sensor interface 10, 20, 20*, 20**, 30, 40 Corrugated bellows / corrugated profile 11 End side / front side 12 End side / end side 14 Section, spiral 15 annular flange, end side 16 annular flange, front side 17 groove / recess 17b groove width 18 bulge 18b bulge width 19s pitch 21, 22 sections, flat 25, 26 annular flanges 33 middle section 34l section with left-hand spiral 34r section with right-hand spiral 35 annular flange, end side 36 annular flange, front side 41, 42 sections, flat 43 middle section, flat 44l section with left-hand spiral 44r section with right-hand spiral 45, 46 annular flanges 47 outer sleeve 48 supply hose 49 outlet hose 50 metering system 51 actuator assembly instruction manual 19 / 21 pages 22 CN 121444644 ​​A 52 Fluid assembly 53 Push rod device 53a Discharge element or sealing element / push rod 54 Nozzle 55 Nozzle opening 56 Supply channel 57 Housing / Housing block 58, 58* Recess / Actuator chamber 58w Wall / Inner circumferential surface of actuator chamber 58iax Inlet, axial 58irad Inlet, radial 58orad Outlet, radial 59 Additional recess / Actuating chamber 59o OutletAdditionally, within the discharge element area: 60 Transmission mechanism, 61 Annular seal, 62 Screw, 63 Transmission lever / lever, 64 Pressure component, 65 Lever support, 66 Contact surface (lever), 67 Contact surface (push rod head), 68 Push rod head, 69 Push rod spring, 70 Actuator spring, 71 Push rod support, 72 Push rod seal, 73 Push rod tip, 74 Sealing seat, 75 Nozzle chamber, 76 Metering material supply pipe, a10, a20, a30, a40 Spacing, b40 Spacing / gap between two spiral sections, he height / position of the upper end section of the bellows, hf height / position of the lower end section of the bellows, hm height / center between the end sections of the bellows, AR Discharge direction, D Metering material / metering medium, K Inclined axis, Instruction manual 20 / 21 pages, 23 CN 121444644 ​​AM Cooling medium / air, RAX Axial direction, RRAD Radial direction, RAZ Azimuth direction, WRAX, AZ Winding direction. Instruction manual page 21 / 21, 24 CN 121444644 ​​A, Figure 1, Figure 2; Instruction manual figure 1 / 11, page 25 CN 121444644 ​​A, Figure 3; Instruction manual figure 2 / 11, page 26 CN 121444644 ​​A, Figure 4; Instruction manual figure 3 / 11, page 27 CN 121444644 ​​A, Figure 5; Instruction manual figure 4 / 11, page 28 CN 121444644 ​​A, Figure 6; Instruction manual figure 5 / 11, page 29 CN 121444644 ​​A, Figure 7; Instruction manual figure 6 / 11, page 30 CN 121444644 ​​A, Figure 8, Figure 9; Instruction manual figure 7 / 11, page 31 CN 121444644 ​​A, Figure 10; Instruction manual figure 8 / 11, page 32 CN 121444644 ​​A, Figure 11; Instruction manual figure 9 / 11, page 33 CN 121444644 ​​A Figure 12: Appendix to the instruction manual, page 10 / 11, 34 CN 121444644 ​​A Figure 13: Appendix to the instruction manual, page 11 / 11, 35 CN 121444644 ​​A

Claims

1. An actuator module (1) having a module housing (3) which is tightly closed and extends in an axial direction (R AX ) longitudinally, having at least one piezoelectric actuator (2) arranged in the module housing (3), and having at least an electrical interface (6a, 6b) for the piezoelectric actuator (2), which interface (6a, 6b) is guided through a module housing wall (3w).​ wherein A module housing inner cavity (3i) between the piezoelectric actuator (2) and the module housing wall (3w) comprises a potting (4) which electrically insulates the module housing wall (3w) from the piezoelectric actuator (2) and is configured to be thermally conductive, in particular with a thermally conductive auxiliary material, wherein the module housing wall (3w) of the module housing (3) has a corrugated pocket (10, 20, 30, 40) with a corrugated profile (10, 20, 30, 40), wherein at least one section (14, 34l, 34r, 44l, 44r) of the corrugated profile (10, 20, 30, 40) is configured helically along an axial direction (R AX ).

2. The actuator module of claim 1, wherein, the potting (4) comprises a base material (4a) and an auxiliary material (4b), wherein preferably the base material (4a) is a hardened material (4a) and the auxiliary material (4b) is at least granular, thermally conductive and dielectric, wherein the auxiliary material (4b) is arranged in the potting (4) such that, in operation, a thermal discharge from the piezoelectric actuator (2) to the module housing wall (3w) takes place via the potting (4), in particular via the auxiliary material (4b).

3. The actuator module of claim 1 or 2, wherein, The helical segments (14, 34l, 34r, 44l, 44r) begin in the axial direction (R AX ) at a distance (a 10 , a 20 , a 30 , a 40 ) from the respective end side (11, 12) of the module housing (3) and extend therefrom at least section-wise to the other end side (12, 11), preferably at least to the middle of the bellows (10, 20, 30, 40).

4. The actuator module of any of the preceding claims, wherein, The module housing wall (3w) of the module housing (3) has, in the respective end region near the respective end side (11, 12), a flat section (21, 22, 41, 42) which adjoins the helical section (14, 34l, 34r, 44l, 44r) on the end side.

5. The actuator module of any of the preceding claims, wherein, The module housing wall (3w) and / or the corrugated pocket (20*) of the module housing (3) has at least one module housing edge recess (3a), preferably four module housing edge recesses (3a), wherein the at least one module housing edge recess (3a) has a particularly preferably concave cross section.

6. The actuator module of any of the preceding claims, wherein, The corrugated bellows (30, 40) have at least two counter-rotating helical segments (34l, 34r, 44l, 44r) in the axial direction (R AX ), wherein preferably at least two of the helical segments (34l, 34r, 44l, 44r), particularly preferably having counter-rotating winding directions (WR AX,AZ ) to one another, are separated from one another.

7. The actuator module of any of the preceding claims, wherein, The at least two helical segments (34l, 34r, 44l, 44r) are separated from each other by a flat segment (43) which is preferably arranged in the middle of the bellow (40) from which flat segment the helical segments respectively extend in axial direction (R AX ) towards the end sides (11, 12).

8. The actuator module of any of the preceding claims, wherein, At least one helical section (14, 34l, 34r, 44l, 44r) of the corrugated pocket (10, 20, 30, 40) has a pitch (19s) of at least 1 mm, preferably at least 5 mm, particularly preferably at least 10 mm, and / or a pitch of at most 35 mm, preferably at most 20 mm, particularly preferably at most 15 mm.

9. The actuator module according to any of the preceding claims, having a hose-like outer casing (47), wherein, The jacket (47) has at least two openings.

10. A metering system (50) for a metering material (D) with a nozzle (54) for outputting the metering material (D), a supply channel (56) for the metering material (D), a discharge element (53a) and at least one actuator module (1) coupled to the discharge element (53a), wherein The metering system (50) has a housing (57) with at least one columnar recess (58, 58*), in which the actuator module (1) according to any one of claims 1 to 9 is preferably a precise fit in the recess in a metering operation, wherein, for cooling, the housing (57) has an inlet (58i ax , 58i rad ) into the recess (58, 58*) for conducting a cooling medium (M) into the groove (17) on the outside of the bellows (10, 20, 30, 40) and the housing (57) has at least one outlet (58o rad ) from the recess (58, 58*) for conducting the cooling medium (M) out of the groove (17).

11. The metrology system of claim 10, wherein, The recess (58) of the metering system (50) has at least one radial inlet (58i rad ) and / or radial outlet (58i rad ), which, when the actuator module (1) with the module housing (3) is installed in the metering system (50), is preferably located substantially on the level (h e ) of the upper end section and / or on the level (h f ) of the lower end section of the module housing (3).

12. The metrology system of claim 10 or 11, wherein, At least one of the walls (58w) axially delimiting the recess (58, 58*) of the housing (57) has an inlet (58i ax ) or an outlet, Or wherein one of the walls (58w) has an inlet (58i ax ) and the other wall has an outlet.

13. The metrology system of any one of claims 10-12, wherein, In the actuator module (1) according to the invention, the recess (58) has an inlet (58i) for the introduction of the cooling medium (M) in a radial wall (58w) centrally between the end sides (11, 12) of the module housing (3) when the module is mounted according to the regulations rad .

14. The metrology system of any one of claims 10-13, wherein, In a metering system (50) with a transmission mechanism (60) arranged in a further recess (59) between the piezoelectric actuator (2) and the discharge element (53a), and / or In a metering system (50) with a transmission mechanism (60) arranged in a further recess (59) between the piezoelectric actuator (2) and the discharge element (53a), wherein at least one inlet (58i ax ) is configured at an axial end region of the corrugated bladder (10, 20, 30, 40) for introducing the cooling medium (M) preferably from an axial direction (R AX ).

15. The metrology system of any one of claims 10-14, wherein, Preferably, the metering system (50) has an inlet (58i ax ) on the end region of the bellows (10, 20, 30, 40) on the end side of the piezoelectric actuator (2), the housing (57) having, on the front side of the piezoelectric actuator (2), a further recess (59) extending preferably transversely thereto, in which a transmission lever (63) is arranged, which transmits the longitudinal extension of the piezoelectric actuator (2) via the lever arm of the transmission lever (63) to the discharge element (53a) of an elastically supported push rod device (53), Wherein the outlet (59o) for the cooling medium (M) is arranged in the region of the further recess (59), close to the elastically supported push rod device (53).

Images