MODULAR MEASURING DEVICE

Description

[0001] The invention relates to a modular measuring device for detecting a mass flow, a viscosity, a density and / or a variable derived therefrom of a flowable medium, in particular a modular Coriolis flow meter for preferably pharmaceutical bioprocess applications.

[0002] Field devices for process measurement technology with a vibration-type sensor, and in particular Coriolis flowmeters, have been known for many years. The basic design of such a measuring device is described, for example, in EP 1 807 681 A1, whereby the design of a generic field device is fully incorporated by reference in this document within the scope of the present invention.

[0003] Typically, Coriolis flowmeters have one or more vibrating measuring tubes, which are set into vibration by a vibration exciter. These vibrations are transmitted along the length of the tube and are varied by the type of fluid contained in the measuring tube and its flow velocity. A vibration sensor, or in particular two spaced-apart vibration sensors, can record the varied vibrations at another location along the measuring tube in the form of one or more measurement signals. An evaluation unit can then use the measurement signal(s) to determine the mass flow, viscosity, and / or density of the medium. The vibrating measuring tubes are usually integrally connected to process connections and the housing via distributor pieces.

[0004] Coriolis flowmeters with replaceable disposable measuring tube assemblies with a modular design are known, in which no material connections are provided between the measuring tubes and the housing, thus ensuring the exchange of the measuring tube. For example, WO 2011 / 099989 A1 teaches a method for producing a monolithic measuring tube assembly of a Coriolis flowmeter with curved measuring tubes. The measuring tube body of the respective measuring tubes is first formed from a solid polymer, and the channel for guiding the flowable medium is subsequently machined into the assembly. WO 2011 / 099989 A1, like US Pat. No. 10,209,113 B2, teaches a fixing body assembly designed to receive and support a replaceable measuring tube module comprising thin-walled plastic tubes.The measuring tube modules are mounted in a carrier module equipped with the necessary exciters and sensors using the fixing body arrangement.

[0005] WO 2020 / 035305 A1 discloses a modular Coriolis flowmeter having a body with a fluid channel that can be connected to process connections via holding elements for releasable fastening.

[0006] The mechanical properties of measuring tube modules suitable for Coriolis flowmeters can vary considerably. Therefore, specific parameters such as the calibration factor and zero point must be determined before use in a Coriolis flowmeter. It has been found that the zero point determined during the calibration procedure usually deviates from the actual zero point of the replaceable measuring tube module in use. Such a deviation is difficult to predict. One reason for this is the extremely difficult-to-reproduce degree of attachment of the measuring tube module to the support module. Another influence is microfriction between the measuring tube and support module.

[0007] The invention is based on the object of providing a user-friendly, modular measuring device whose zero point in use deviates only minimally from the zero point determined in the adjustment process.

[0008] The problem is solved by the modular measuring device according to claim 1.

[0009] The modular measuring device according to the invention for detecting a mass flow, a viscosity, a density and / or a variable derived therefrom of a flowable medium, in particular a modular Coriolis flow meter for preferably pharmaceutical bioprocess applications, comprises: a measuring tube module, in particular designed as a disposable article, wherein the measuring tube module comprises at least one measuring tube through which a medium can flow, wherein the measuring tube module has a fixing body arrangement fastened to the at least one measuring tube; a vibration exciter which is configured to excite the measuring tube to vibrate, in particular comprising an excitation magnet and an excitation coil, wherein at least one component of the vibration exciter, in particular the excitation magnet, is arranged on the measuring tube module; at least one vibration sensor which is configured to detect the vibrations of the at least one measuring tube, in particular comprising a sensor magnet and a sensor coil, wherein at least one component of the vibration sensor, in particular the sensor magnet, is attached to the measuring tube module;a carrier module, in particular comprising a receptacle, the sensor coil and the excitation coil, wherein the measuring tube module can be arranged in the receptacle of the carrier module, wherein the carrier module has a fixing device, wherein the fixing device has a shaft which is at least partially eccentric, wherein the shaft is designed to clamp the measuring tube module in the receptacle via the fixing body arrangement and to connect it to the carrier module in a mechanically releasable manner, characterized in that the shaft is designed as a camshaft mounted on the carrier module, with at least one cam. ;

[0010] Previously known fixing devices have the disadvantage that, on the one hand, they do not adequately protect the measuring tube module against external disturbances and micro-frictions and, on the other hand, the degree of fixing is not reproducible, so that in most cases, after fixing the measuring tube module in the carrier module, the actual zero point deviates from the zero point determined in the adjustment procedure.

[0011] A shaft is an elongated, particularly cylindrical, rotating body used to transmit rotary motion and torque. It is typically supported by at least one pivot bearing on the support module. When torque is transmitted, the shaft is subjected to torsion. The eccentric part of the shaft presses against the locating body assembly, thus clamping it in the mount.

[0012] In the context of the invention, the mechanically detachable connection of the measuring tube module to the support module is understood to mean a replaceable connection in which no integral connections need to be removed. It is particularly user-friendly if no additional mechanical tools—such as screwdrivers—are required for the mechanically detachable connection of the measuring tube module.

[0013] A camshaft is a rod-shaped body—similar to a shaft—on which at least one, particularly rounded, projection—the so-called cam—is mounted. The rod-shaped body rotates around its own axis, and the cam(s) mounted on it repeatedly convert this rotational movement into a short longitudinal movement.

[0014] When the at least one measuring tube is excited, the fixing body assembly also begins to vibrate, as it is connected to the at least one measuring tube. Such movement is detrimental to measurement performance. Fixing the assembly using a camshaft suppresses these vibrations. The cam of the camshaft pushes the fixing body assembly toward the holder and clamps it in the holder. This prevents any movement of the measuring tube module in the holder.

[0015] Advantageous embodiments of the invention are the subject of the subclaims.

[0016] One embodiment provides that the fixing body arrangement has a recess which is designed to be at least partially complementary to the eccentric section of the shaft, in particular to the at least one cam, wherein the recess is designed to form an at least positive connection with the eccentric section of the shaft, in particular with the at least one cam.

[0017] A recess in the fixing body assembly has the advantage of ensuring that the measuring tube module and / or the shaft are correctly positioned. Only when the eccentric section of the shaft or the cam can be inserted into the recess with a positive fit are the measuring tube module and the support module in a desired position relative to each other, thus preventing any zero point deviation caused by incorrect positioning and / or fixing of the measuring tube module.

[0018] One embodiment provides that the fixing body arrangement, in particular the shaft and preferably the camshaft, is mounted so as to be movable in a longitudinal direction.

[0019] Such a design enables convenient operation of the locking device and user-friendly replacement of the measuring tube module with excellent reproducibility of the force-locking and / or positive connection. The user moves the shaft or camshaft longitudinally, thus exposing the receptacle so that the measuring tube module can be inserted. To secure the measuring tube module, the shaft or camshaft is moved back to the closed position and rotated to clamp the measuring tube module in the receptacle.

[0020] One embodiment provides that the fixing device, in particular the shaft, is designed such that a movement in a longitudinal direction is possible at least in sections exclusively in a discrete number of orientations, in particular in exactly one orientation and preferably in exactly two orientations of the fixing device, in particular of the shaft and preferably of the camshaft.

[0021] This results in the advantage that when replacing the measuring tube module, the shaft or camshaft can be prevented from falling out of one of the pivot bearings and a more reproducible positioning of the eccentric section or the at least one cam in a predetermined target position is realized.

[0022] The invention is explained in more detail with reference to the following figures. They show: Fig. 1 : a perspective view of a design of a modular Coriolis flowmeter; Fig. 2 : in three perspective views, the fixing of a measuring tube module in a receptacle of a carrier module by means of an embodiment of the fixing device according to the invention; and Fig. 3 : a cross section through a design of the camshaft and a fixing body arrangement with a recess.

[0023] The Fig. 1shows a perspective view of a measuring device for pharmaceutical bioprocess applications. It is explicitly a modular Coriolis flowmeter. The measuring tube module 4 is suitable for being inserted into a carrier module 16 in an exchangeable and mechanically detachable manner. The mechanically detachable connection is made via a fixing device arranged on the carrier module (not shown). To enable easy replacement of the measuring tube module 4, only individual components of the vibration exciter 7 and the vibration sensors 8.1, 8.2, in this case the respective magnet arrangements 9.1, 9.2, are attached to the measuring tube module 4. These do not require an electrical connection to a measuring and / or operating circuit 15. The other components of the vibration exciter 7 and the vibration sensors 8.1, 8.2 are arranged on the carrier module 16, in particular in the receptacle 23, which is suitable and designed for receiving the measuring tube module 4.The measuring tube module 4 comprises two curved, parallel measuring tubes 3.1, 3.2, which are connected to one another via a coupler arrangement 1 consisting of four coupling elements 6.1, 6.2, and a fixing body arrangement 5. Alternatively, the measuring tube module 4 can also comprise exclusively one measuring tube 3.1, 3.2 or more than two measuring tubes 3.1, 3.2. Two coupling elements 6.1 are integrally mounted in an inlet and two coupling elements 6.2 are integrally mounted in the outlet of the respective measuring tubes 3.1, 3.2. The measuring tubes 3.1, 3.2 are shaped such that the flow direction, represented by two arrows, in the inlet is oriented opposite to the flow direction in an outlet. A flow divider can be arranged in each of the inlet and outlet, which flow divider has a process connection for connection to a hose and / or plastic pipe system.According to one embodiment, exactly one flow divider body can be provided instead of two separate flow dividers, which is pushed onto the inlet and outlet and helps to decouple the measuring tube module 4 from ambient interference after installation in the carrier module 16. The individual coupling elements 6.1, 6.2 are plate-shaped and consist of one or two parts. The coupling elements 6.1, 6.2 can each completely or partially encompass the measuring tubes 3.1, 3.2. The measuring tubes 3.1, 3.2 shown are U-shaped, i.e. they each have two legs 11 that run essentially parallel to one another and are connected by a curved section. Exactly one magnet arrangement 9.1, 9.2 is arranged on each measuring tube 3.1, 3.2. In the curved section, a magnet 10.1 of the magnet arrangement 9.1 is arranged, which forms a component of the vibration exciter 7.A magnet 10.2 is mounted in each of the legs 11, forming part of the vibration sensor 8.1, 8.2. The magnets 10.1, 10.2 are attached to mounting surfaces. In the present embodiment, the mounting surfaces are located on the respective measuring tubes 3.1, 3.2. Alternatively, the measuring tube module 4 can also have one or more straight measuring tubes 3.1, 3.2, or the shape of the measuring tubes 3.1, 3.2 can differ from the shape shown.

[0024] The measuring tube module 4 is partially inserted into a receptacle 23 of a carrier module 16. An arrow indicates the direction of insertion. According to the embodiment, the direction of insertion runs perpendicular to a longitudinal direction of the receptacle 23. The receptacle 23 can also be designed such that the measuring tube arrangement 4 is inserted in the longitudinal direction of the receptacle 23 (not shown). The carrier module 16 has a measuring and / or operating circuit 15, which is connected to the two vibration exciters 7 and a total of four vibration sensors 8.1, 8.2, in particular to the respective coil devices 25, and is configured to generate and / or detect a temporally changing magnetic field. The carrier module 16 has a carrier module body 22, which delimits the receptacle 23. The fixing body arrangement 5 of the measuring tube module 4 has mounting surfaces 26, which serve to arrange the measuring tube module 4 in a predetermined position in the carrier module 16.According to the illustrated embodiment, the plumb line of the mounting surface 26 points perpendicular to the longitudinal direction of the measuring tube module 4. According to a further advantageous embodiment, the plumb line of the mounting surface 26 points in the direction of the longitudinal direction of the measuring tube module 4. The surface of the carrier module body 22 that is in contact with the mounting surface 26 of the fixing body arrangement 5 is referred to as the support surface 27.

[0025] The carrier module 16 has two mutually parallel side surfaces, which delimit the receptacle 23 transversely to the longitudinal direction of the receptacle 23. The coil devices 25 of the vibration sensors 8.1, 8.2 and the coil device 25 of the vibration exciter 7 are arranged on or in the side surfaces. The coil devices 25 of the vibration sensors 8.1, 8.2 are arranged offset in the longitudinal direction of the receptacle 23 relative to the coil device 25 of the vibration exciter 7. Furthermore, the three coil devices 25 are designed as plate coils and are recessed into the side surfaces. On the side surface, three coil devices 25 are arranged substantially opposite the corresponding magnet arrangements 9.1, 9.2. A guide is incorporated into each of the two side surfaces, which extends perpendicular to the longitudinal direction of the receptacle 23 and parallel to the coil plane.According to the embodiment shown, the receptacle 23 extends over two end faces of the receptacle 23. This enables insertion of the measuring tube module 4 perpendicular to the longitudinal direction of the measuring tube module 4. According to a further embodiment, the receptacle 23 extends exclusively over one end face of the carrier module 16. In this case, the measuring tube module 4 is to be inserted into the carrier module 16 in the longitudinal direction of the measuring tube module 4 - or of the carrier module 16.

[0026] The Fig. 2shows, in three perspective views, the fixing of a measuring tube module 4 in a receptacle of a carrier module 16 by means of an inventive embodiment of the fixing device 34. The measuring tube module 4 is arranged in the receptacle 23 of the carrier module. The fixing device 34 has a shaft 100 which is at least partially eccentric and is designed to clamp the measuring tube module 4 in the receptacle via the fixing body arrangement 35 and to mechanically releasably connect it to the carrier module 16. In the case shown, the shaft 100 of the fixing device 34 is designed as a camshaft mounted on the carrier module 16, with a cam 101. In order to adapt the fixing of the measuring tube module 4 in the receptacle 23 depending on the application, more than the one cam 101 shown can also be provided.The shaft 100 is mounted so as to be movable in a longitudinal direction of the shaft 100 so that it does not block the receptacle when the measuring tube module 4 is inserted (see first view). A first projection 102 on the shaft 100 prevents the shaft 100 from falling out, thereby enabling user-friendly assembly of the measuring tube module 4. The first projection 102 is not intended to clamp the measuring tube module 4 in the receptacle 23. The fixing device 34 also comprises a first pivot bearing 104 and a second pivot bearing 105 for guiding the shaft 100 to desired degrees of freedom. The shaft 100 is mechanically detachable and can be connected to the first pivot bearing 104 and the second pivot bearing 105 so as to be rotatable about its own longitudinal axis. The cam 101 has at least one fixing surface 42, and the fixing body arrangement 35 accordingly has at least one support surface 44.When the measuring tube module 4 is installed in the receptacle of the support module 16, the at least one fixing surface 42 or the exact one fixing surface 42 of the cam 101 rests on the at least one support surface 44 of the fixing body arrangement 35, resulting in a force-locking and / or positive connection of the measuring tube module 4 to the support module. This connection is created by rotating the shaft 100 about its own longitudinal axis.

[0027] The shaft 100 is also designed such that movement thereof in a longitudinal direction is possible, at least in sections, exclusively in a discrete number of orientations of the shaft 100. In a first section, the shaft 100 can be guided through in exactly one orientation in sections, and in a second section, the shaft 100 can be guided through in exactly two orientations in sections. In the embodiment shown, this is achieved in that the shaft 100, in addition to the cam 101, has the first projection 102 and a second projection 106. Like the first projection, the second projection 106 is also not designed to form the positive and / or non-positive connection. The first projection 102 and the second projection 106 each extend radially from the shaft 100.The first projection 102 and the second projection 106 are arranged offset relative to the cam 101 and to one another in the longitudinal direction of the shaft 100. The first projection 102 and the second projection 106 are arranged and spaced apart on the shaft 100 in such a way that, at least after the cam 101 has been guided out by the second pivot bearing 105, movement of the shaft 100 in the direction of the longitudinal axis is blocked and is preferably only possible in exactly one orientation of the shaft 100. This is achieved according to the embodiment by means of a slot. Alternatively, the shaft and the first projection 102 can be formed in two parts, i.e. the first projection 102 can be arranged as a separate component in a receptacle of the shaft 100.While the first projection 102 serves to prevent the shaft 100 from falling out of the first pivot bearing 104 during assembly, the second projection 106 essentially serves to limit the movement of the shaft 100 in its longitudinal direction and thus bring the cam 101 into the intended target position (see second view). The second projection 106 can thus also be annular or at least not complementary to the opening in the bearing through which the shaft 100 is to be guided. The illustrated shaft 100 has a lever at one end to facilitate the operation of the fixing device 34.

[0028] Based on the orientation of the shaft 100 in the second view, rotating the shaft, in this case by 180°, results in a positive and / or non-positive connection with the fixing body arrangement 35 of the measuring tube module 4 (see third view). Alternatively, an electronic device can be provided that causes the movement of the shaft 100 in its longitudinal direction and the rotation of the shaft 100 about the longitudinal axis, for example, by means of a linear and / or rotary motor.

[0029] The Fig. 3shows a cross-section through a configuration of the camshaft and a fixing body arrangement 35 with a recess 103, which is at least partially complementary to the at least one cam 101 or the eccentric section of the shaft. The recess 103 is designed to form an at least positive connection with the at least one cam 101 or the eccentric section and thus to clamp the measuring tube module in the receptacle via the fixing body arrangement 35. In the configuration shown, the support surface extends into the recess 103. List of reference symbols

[0030] Coupler arrangement 1 Measuring device 2 Measuring tube 3.1, 3.2 Measuring tube module 4 Fixing body arrangement 5 Coupler element 6.1, 6.2 Vibration exciter 7 Vibration sensor 8.1, 8.2 Magnet arrangement 9.1, 9.2 Magnet 10.1, 10.2 Leg 11 Measuring and / or operating circuit 15 Carrier module 16 Receptacle 23 Side surface 24 Coil device 25 Mounting surface 26 Side surface 27 Fixing device 34 Fixing body arrangement 35 Fixing surface 42 Support surface 44 Shaft 100 Cam 101 First projection 102 Recess 103 First pivot bearing 104 Second pivot bearing 105 Second projection 106

Claims

1. Modular measuring device (2) for measuring a mass flow, a viscosity, a density and / or a variable derived therefrom of a flowable medium, in particular a modular Coriolis flowmeter for preferably pharmaceutical bioprocess applications, comprising: - a measuring tube module (4) designed in particular as a disposable article, the measuring tube module (4) comprising at least one measuring tube (3.1, 3.2) through which a medium can flow, the measuring tube module (4) having a fixing body arrangement (35) attached to the at least one measuring tube (3); a vibration exciter (7) which is set up to excite the measuring tube (3) to vibrate, in particular comprising an exciter magnet (36) and an exciter coil (37); at least one component of the vibration exciter (7), in particular the exciter magnet (36), being arranged on the measuring tube module (4); at least one vibration sensor (8.1, 8.2) which is set up to detect the vibrations of the at least one measuring tube (3.1, 3.2), in particular comprising a sensor magnet (38) and a sensor coil (39), wherein at least one component of the vibration sensor (8.1, 8.2), in particular the sensor magnet (38), is attached to the measuring tube module (4); - a carrier module (16), in particular comprising a receptacle (23), the sensor coil (39) and the exciter coil (37), wherein the measuring tube module (4) can be arranged in the receiver (23) of the carrier module (16), the carrier module (16) having a fixing device (34), the fixing device (34) having a shaft (100) which is designed to be eccentric at least in sections, the shaft (100) being set up to clamp the measuring tube module (4) in the receptacle (23) by means of the fixing body arrangement (35) and to connect it mechanically releasably to the carrier module (16), characterized in that the shaft (100) is designed as a camshaft, which is mounted on the carrier module (16) and has at least one cam (101).

2. Modular measuring instrument (2) according to claim 1, wherein the fixing body arrangement (35) has a recess (103) which is at least partially complementary to the eccentric portion of the shaft (100), in particular to the at least one cam (101), wherein the recess is configured to form an at least form-fitting connection with the eccentric portion of the shaft (100), in particular with the at least one cam (101).

3. Modular measuring instrument (2) according to at least one of the preceding claims, wherein the fixing body arrangement (35), in particular the shaft (100) and preferably the camshaft, is mounted so as to be movable in a longitudinal direction.

4. Modular measuring instrument (2) according to claim 3, wherein the fixing device (34), in particular the shaft (100), is designed such that a movement in the longitudinal direction is possible at least in sections exclusively in a discrete number of orientations, in particular in precisely one orientation and preferably in precisely two orientations of the fixing device (34), in particular of the shaft (100) and preferably of the camshaft.