Actuator for controlling the fluid paths of a filling unit for a beverage filling system, filling unit, and beverage filling system

Abstract

An actuator that controls flow through a fluid path during filling of beverages includes an actuator element that exerts an actuating force. In response to control signals, the actuator element transitions between an elongated state and a resting state.

Claims

1. An apparatus comprising an actuator that controls flow through a fluid path during filling of beverages, said actuator comprising a folding bellows, a control unit, and an actuator element that exerts an actuating force, wherein the control unit causes first and second control signals, wherein said actuator element transitions between an elongated state and a resting state in response to said control signals, and wherein said actuator element is one of a plurality of actuator elements that are connected in series to form at least part of said folding bellows.

2. The apparatus of claim 1, wherein said actuator element is a first actuator element, wherein said actuator comprises a second actuator element, and wherein said first and second actuator elements are connected in series, whereby connecting said first and second actuator elements in series increases an extent to which said actuator changes an overall length of said actuator.

3. The apparatus of claim 1, wherein said actuator element comprises an elastomer.

4. The apparatus of claim 1, wherein said actuator element comprises a dielectric elastomer.

5. The apparatus of claim 1, wherein said actuator element comprises a piezoelectric pressure sensor, whereby said actuator element is able to both control a fluid path and to sense pressure along the fluid path, thereby integrating two functions into a single structure.

6. An apparatus comprising an actuator and a filling unit, wherein said actuator controls flow through a fluid path of said filling unit during filling of a container with beverage, wherein said actuator comprises an actuator element that exerts an actuating force and a control unit that causes first and second control signals, wherein said actuator element transitions between an elongated state and a resting state in response to said control signals, wherein said actuator element comprises a magnetorheological elastomer, wherein said actuator element is fixed to a housing and comprises an end that faces fluid path, and wherein in said resting state, said magnetorheological elastomer's shape depends at least in part on forces arising from flow of said beverage through said fluid path.

7. The apparatus of claim 6, further comprising a beverage filling-system, wherein said filling unit is a constituent of said beverage-filling system.

8. The apparatus of claim 6, wherein the actuator element exerts an actuation force that is between 350 and 370 newtons.

9. The apparatus of claim 6, further comprising a diaphragm that transitions between sealing said fluid path through which beverage flows and opening said fluid path as said actuator element, to which said diaphragm is coupled, transitions between an elongated state and a resting state.

10. The apparatus of claim 6, wherein said actuator element exerts said actuation force as a result of causing deformation of a material from which a body of said actuator is made.

11. The apparatus of claim 6, further comprising a membrane arranged with said actuator element such that said actuator element causes said membrane to move along a lifting path.

12. The apparatus of claim 6, wherein the actuator is maintained in a given shape before and after actuation.

13. The apparatus of claim 6, wherein said magnetorheological elastomer is fixed to said housing.

14. The apparatus of claim 6, further comprising an electromagnet that activates said magnetorheologic elastomer in response to said control signal from said control unit.

15. The apparatus of claim 6, wherein said actuator element that exerts said actuating force is said magnetorheological elastomer and wherein said magnetorheological elastomer exerts said actuating force as a result of a transition between said elongated state and said resting state.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further details and advantages of the invention are now explained in greater detail on the basis of the exemplary embodiment represented in the drawings, in which:

(2) FIG. 1 shows a beverage filling-system with a filling unit and an actuator;

(3) FIGS. 2a-d show an actuator that relies on a dielectric elastomer;

(4) FIGS. 3a-b show an actuator that relies on a magnetorheological elastomer;

(5) FIGS. 4a-b show an actuator that relies on shape-memory alloys;

(6) FIGS. 5a-b show an actuator that relies on magnetorheological fluids in a casing; and

(7) FIGS. 6a-b show an actuator that relies on piezoelectric ceramics.

DETAILED DESCRIPTION

(8) FIG. 1 shows a beverage filling-system 10 having a filling unit 12 with an actuator 14 that controls whether or not a fluid path 20 is open or closed. The actuator 14 is arranged together with a diaphragm 16 in a housing 18 of the filling unit 12. At a free end of the actuator 14 is a damping element 25.

(9) The diaphragm 16 is a fluid-valve diaphragm having a membrane that has a lifting path of approximately six millimeters or more, and in some cases, more than ten millimeters. The fluid path 20 has an extent of about twenty-four millimeters.

(10) The actuator 14 includes an actuator element 24 that responds to a control signal from a control unit 22. This control signal causes the actuator 14 to transition between first and second switching positions. In the first switching-position, the actuator 14 releases the diaphragm 16. In the second switching-position, the actuator 14 actuates the diaphragm 16 so that the diaphragm 16 seals the fluid path 20.

(11) The actuator element 24 assumes first and second elongations in response to first and second control signals from the control unit 22. The first elongation causes the actuator element 24 to assume a resting position. The second elongation causes the actuator element 24 to assume an activation position. In some embodiments, the transition time required to transition in either direction is on the order of forty milliseconds.

(12) In some embodiments, an actuating force associated with these transitions is within the range of two-hundred newtons to four-hundred newtons. Among these are embodiments in which it is between three-hundred fifty and three-hundred seventy newtons. A preferred value is approximately three-hundred sixty newtons.

(13) In some embodiments, working pressures can lie in the range between three to ten bar, in particular eight bar, or, with the adjustment of the diaphragm surface area of the diaphragm 16, about six bar.

(14) The actuator element 24 transitions between first and second switching positions that cause the diaphragm 16 to transition between first and second states. In the first state, the diaphragm seals the fluid path 20. This is the diaphragm's “closed position.” In the second state, the diaphragm 16 leaves the fluid path 20 open. This is the diaphragm's open position.

(15) One of the first and second states is a default state. This is the state of the diaphragm 16 when the actuator 14 has not been actuated. In some embodiments, the diaphragm 16 is in the second state when the actuator 14 is not actuated. This is a “normally open” configuration. In other embodiments, the diaphragm 16 is in its second state when the actuator 14 is not actuated. This is the “normally closed” configuration.

(16) In an alternative embodiment, which is similar to that shown in FIG. 1, the actuator element 24 has a stable shape. In this embodiment, an end actuator replaces the damping element 25.

(17) FIGS. 2a-d shows a first embodiment of an actuator assembly 114 as shown in FIG. 1 surrounded by a bellows 124. The illustrated actuator assembly 114 relies on the electrical response of a dielectric elastomer.

(18) A control unit 22 causes a current source 116 to apply a current by connecting a voltage source that maintains a voltage U. This actuates the actuator assembly 114, which then causes the diaphragm 16 to enter a conical-cylindrical expansion chamber 122 of the fluid path 21, thus sealing the fluid path 21.

(19) As is apparent from the figures, the actuator assembly 114 comprises actuators 114′ connected in series to increase the extent to which the actuator assembly 114 can change its overall length.

(20) FIG. 2c shows a first actuator 114 that has contracted as a result of having been de-energized and short-circuited. FIG. 2d shows the first actuator 114 after it has elongated as a result of having been subjected to an electrical stimulus. In the example shown, the first actuator 114 would cause a normally-open configuration. However, it is possible to reconfigure the actuator 114 so that the result is a normally-closed configuration.

(21) FIGS. 3a and 3b show a second actuator 214 in which a magnetorheologic elastomer surrounds the actuator 214. The magnetorheologic elastomer 216 comprises a soft elastomer matrix into which magnetic particles have been introduced.

(22) An electromagnet 218 activates the magnetorheologic elastomer 216 in response to a control signal from the control unit 22. The second actuator 214 can be implemented so that it is normally closed or normally open. The particular embodiment shown in FIGS. 3a and 3b is one that is normally open.

(23) FIG. 3a shows the second actuator 214 in a state in which it has contracted. In this state, the electromagnet 218 is turned off. At the molecular level, the molecules are not polarized and not aligned. They are chaotically distributed. As a result, the actuator 214 is essentially folded together.

(24) In the state shown in FIG. 3a, the electromagnet 218 has been switched off. This means that the shape of the magnetorheologic elastomer 216 depends on external forces exerted upon it. In the illustrated embodiment, these forces include forces exerted by the bellows as it returns to its default shape, forces resulting from, forces arising from a flow through first and second fluid paths 224′, 224″ or any combinations thereof. In some embodiments, as shown in FIG. 1, a return spring contributes to these external forces.

(25) In the state shown in FIG. 3b, the electromagnet 218 has been turned on, thus polarizing and aligning the molecular constituents that comprise the magnetorheological elastomer 216. This expands the magnetorheological elastomer 216 and causes it to assume a shape in which the diaphragm 16 presses against an outflow opening of the first fluid path 224′, thus sealing it shut. This force is great enough to overcome a resetting force, such as that exerted by a return spring.

(26) FIGS. 4a and 4b show a further embodiment of an actuator 314 that can be used in the filling unit 12 shown in FIG. 1. As shown in the figures, the filling element includes an inlet 322 and an outlet 322″. A diaphragm 320 coupled to the alloy 316 seals the fluid inlet 322 as shown in FIG. 4b.

(27) In this embodiment, the actuator 314 comprises a shape-memory alloy 316 that changes shape in response to a stimulus. In the embodiment described below, the stimulus is heating or cooling. However, a shape-memory alloy that responds to a magnetic stimulus can also be used.

(28) The embodiment shown in FIGS. 4a and 4b includes a heater 318 that turns on and off in response to instructions from the control unit 22. In this embodiment, the heat from this heater 318 is the stimulus that causes the shape-memory alloy to change shape. The change in shape causes the actuator 314 to transition between the two states shown in FIGS. 4a and 4b.

(29) The actuator 314 can be configured so that it assumes the state shown in FIG. 4a when the heater 318 is turned off, in which case the actuator is normally open. Or the actuator 314 can be configured to assume the state shown in FIG. 4b when the heater 318 is turned off, in which case the actuator 314 is normally closed.

(30) In some embodiments, a return spring that engages from inside or outside resets the actuator 314. Such a return spring is particularly important when the material responds to a stimulus in only one direction. For example, there are materials that will change state when a stimulus is applied but will not change back to their original state when the stimulus is removed.

(31) In other embodiments, the shape-memory alloy is one that changes shape upon exposure to a magnetic field. In that case, it is a magnet rather than a heater that supplies appropriate stimulus.

(32) In some embodiments, the shape-memory alloy is plastically deformable.

(33) In some embodiments, the shape-memory alloy is a magnetic displaced metal grid. In such cases, heating the alloy 316 produces an austenitic aligned metal grid that changes the shape of the shape-memory alloy. This change in shape moves the diaphragm 320, thus causing it to open or close the fluid path.

(34) In yet another embodiment, shown in FIGS. 5a and 5b, an actuator 414 includes an elastic casing 418 that accommodates a magnetorheological fluid 416. As was the case with the other actuators already described, the actuator 414 can be configured so that it is open in the absence of stimulus or closed in the absence of stimulus. The former is referred to as being “normally open” and the latter is referred to as being “normally closed.” The actuator 414 that is shown in FIGS. 5a and 5b is one that is normally open.

(35) The control unit 22 actuates the actuator 414 using an electromagnet 420. As was the case with other embodiments, the filling unit 12 has a fluid path 20 that has an inlet 422′ and an outlet 422″.

(36) As shown in FIG. 5b, causing current to flow through the electromagnet 420 creates a magnetic field that expands the magnetorheological fluid 416, thus causing the elastic casing 418 to elongate. This causes a diaphragm 424 arranged on the elastic casing 418 to press against the opening of the inlet 422′, thus sealing it shut.

(37) FIG. 5a shows the constituent magnetic particles in the magnetorheological fluid 416 in a chaotic arrangement. When the electromagnet 420 turns on, the resulting magnetic field aligns these particles as shown FIG. 5. This leads to expansion and movement of the actuator 414 toward the inlet 422′. The magnetorheologic fluid can be a liquid or a gel.

(38) FIGS. 6a and 6b show yet another actuator 514 having a stack of piezoelectric element 516 and a soft sealing elastomer 518 that functions as a diaphragm. In this embodiment, the control unit 22 causes imposition of an electric field that changes the shape of the piezoelectric element 516.

(39) As was the case with other embodiments, the filling unit 12 has a fluid path 20 that has an inlet 520′ and an outlet 522″.

(40) As was the case with the other actuators already described, the actuator 514 can be configured so that it is open in the absence of stimulus or closed in the absence of stimulus. The former is referred to as being “normally open” and the latter is referred to as being “normally closed.” The actuator 514 that is shown in FIGS. 6a and 6b is one that is normally open.

(41) In the state without current imposed, as shown in FIG. 6a, the piezoelectric element 516 remains in a relaxed state in which they are not elongated. As a result, the sealing elastomer 518 is not positioned against the inlet 520′.

(42) In the state in which current is imposed, the piezoelectric ceramics transition into their elongated states. This presses the soft sealing elastomer 518, against the opening of the inlet 520′, thus sealing it closed. The switching is carried out, for example, by an inverse piezoelectric effect.

(43) In addition to changing shape in response to an applied electric field, a piezoelectric element also has the property of generating an electric field in response to an applied force that deforms it. This enables the piezoelectric element to also function as a pressure sensor. Therefore, after having closed the inlet 520′ with a set value of force, a change in the force applied to the piezoelectric ceramic will generate its own electric field and hence a voltage. This provides a way to measure pressure in the connected chamber. In this way, the piezoelectric element 516 serves as an actuator as well as a sensor.