Hose coupling and method for use in analysis systems

Description

AREA OF INVENTION

[0001] The invention relates to a hose coupling for use in analysis systems and a method for using the same. BACKGROUND OF THE INVENTION

[0002] Automated analysis systems for use in clinical diagnostics and the life sciences are manufactured by a number of companies. STRATEC® SE, Birkenfeld, Germany, for example, manufactures a range of sample handling and identification devices used in automated analysis systems and other laboratory instruments.

[0003] The most common type of connection for hoses that transmit liquids is the screw coupling. The parts to be connected are usually made of fluoropolymers such as PTFE or FEP, particularly in the fields of analytical and medical technology. These materials are resistant to the media and pressure. Due to their strong creep properties and relatively high hardness, these hoses cannot simply be pushed together for connection. Special screw fittings are used for such couplings.

[0004] The end of a pipe or hose is reshaped, or a flange is formed at its end using heat and pressure to create a tight connection between the fitting and its counterpart. Such a formed flange seals between the face of the fitting and the threaded base of the counterpart. A ring can be placed between the flange and the fitting to decouple torsional forces that may occur when tightening the fitting and counterpart.

[0005] One disadvantage of this method is that the flange forming process requires several tools and aids. These include a holding fixture for the hose and the actual forming tool. A heated mandrel is often used to warm the tube before forming. Furthermore, this type of fitting frequently involves machined components made of materials such as PEEK. The assembly and component manufacturing, in particular, make this type of connection complex. Additionally, producing such a hose connection requires considerable assembly experience and is therefore not very user-friendly. This method is only suitable for rigid fluoropolymer hoses. Thermoplastic elastomers, due to their elasticity and lower Shore hardness, cannot be formed with the necessary precision.

[0006] An alternative to reshaping the pipe or hose end is an insert consisting of a seal with a cylindrical hose connection and a ring for rotational decoupling. For installation, the fitting is pushed over the pipe or hose, followed by the ring, and finally the insert is inserted into the pipe or hose.

[0007] Similar to the connection with the molded hose, this method often allows the use of small, machined parts made of high-quality plastics. The sealing flange consists of a disc with a mandrel. This mandrel is inserted into the hose with a slight protrusion. Due to the hose's high rigidity and the small size of the components, this results in increased assembly effort. Inserting the mandrel into the hose reduces its cross-section, creating flow resistance within the system. Depending on the flow rate, the fluid is compressed before the mandrel and expands after the reduction in cross-section, which can lead to undesirable turbulence.

[0008] Another sealing option is the use of an elastomer seal, which is slipped over the end of the hose, creating a seal on the outside of the hose. With this method, the seal to the hose and the actual sealing fit in the mating part are achieved solely through an elastomeric element. The seal to the mating part is therefore always dependent on proper installation. If the seal is pushed too far onto the hose, there is no connection between the elastomer and the mating part, and the seal is compromised. Installation is difficult due to both the inherent tolerances and the required installation force. It is recommended to use an installation tool, which increases the effort and thus the cost. As with the aforementioned methods, this connection technique is limited to the relatively rigid fluoropolymer hoses.Sliding the connector onto softer hoses would reduce its cross-section. Furthermore, it is questionable whether the sealing element could even shift due to the higher friction.

[0009] A very simple method for connecting hoses with a Shore hardness below 85 A is the use of a so-called barbed connector, where the hose is slipped over a mandrel with a larger outer diameter than the hose's inner diameter. To ensure a secure connection, the mandrel must be mushroom-shaped. This is the most common, tool-free way to connect hoses. It is widely used for low-pressure fluid transport. The hose is simply slipped over the mating fitting. The resulting, sometimes multiple, points of contact between the fitting and hose ensures a tight seal between the two. However, this slip-on method also has some disadvantages. Firstly, depending on the hose's hardness and the chosen overlap between the fitting and hose, assembly can be difficult. With increasing overlap, or...As hose hardness increases, the contact forces, which are usually applied manually, increase significantly. To counteract this, the hose protrusion can be reduced by increasing hose hardness or wall thickness. However, as the protrusion decreases, the pressure resistance of the overall connection also decreases. In pressurized applications and with the use of strongly pulsating pumps, this connection can exhibit undefined instability. The fitting is screwed into a mating part. If the hose is connected to the fitting before the fitting is screwed into the mating part, the connection can loosen due to tension in the hoses caused by twisting.

[0010] For quick connection and disconnection, a Luer lock is very commonly used in medical devices. This type of connection consists of two coupling pieces that are joined and sealed solely by a self-locking cone. In the Luer lock design, an external thread, which can be locked with a 90° turn, creates additional clamping pressure that prevents the conical connection from being pulled apart and thus prevents leaks. One disadvantage of a Luer lock is that the locking components twist against each other, causing the tubing to twist within its elastic range. This can potentially lead to the connection loosening due to the tubing's elasticity, resulting in leaks.

[0011] To prevent this twisting of the hose, it can be pre-tensioned by a 90° turn against the closing direction of the thread. This has the advantage that the hose is tension-free when the coupling is closed. However, this pre-tensioning requires careful operation, and the error rate is correspondingly high. To counteract this problem, there is a rotationally decoupled version. In this case, the locking thread is loosely connected to the actual Luer cone as an additional union nut. When the coupling is to be closed, the mating part simply needs to be placed on top. By tightening the rotationally decoupled union nut, the actual cone, which is connected to the hose, is pressed into the cone of the mating part without any rotation of its own.

[0012] The locking thread of the Luer-Lock coupling is designed for an ergonomically comfortable 1 / 4 turn. To achieve a sufficient 90° rotation angle to switch the coupling partner from loose to tight, a relatively large thread pitch is required. This large thread pitch significantly reduces the self-locking effect of the thread. Consequently, this locking thread only reliably engages and maintains this lock when the Luer cone is firmly connected. In the described rotationally decoupled version, the friction of the Luer cones is eliminated. The rotationally decoupled union nut can only be locked by adhesion between the screw and nut threads (self-locking). However, since this adhesion is reduced by the large thread pitch, there is always a risk of the locking thread loosening on its own. In this case, the holding force consists solely of the two inserted Luer cones.In dynamically loaded systems, oscillating or vibrating connections, and connections exposed to strong temperature fluctuations, this type of coupling can therefore very quickly lead to failures.

[0013] Published U.S. patent application No. US 2018 / 0128405 A1 relates to a single-acting push-to-connect fitting for a conduit, such as a pipe or hose. The fitting comprises a first fitting component and a second fitting component that are connected or assembled to form a fitting assembly. The fitting assembly includes a pipe sealing device and a pipe holding device. A conduit can be manually or otherwise inserted into, held, and sealed within the assembled fitting assembly with a single axial movement, without requiring any further action or movement of the fitting components. A disadvantage of a fitting assembly according to this publication is that it consists of multiple parts, which complicates its assembly.

[0014] Published US patent application No. US 2019 / 0128460 A1 relates to a hose end form comprising a first section having a first radially outward-facing surface and a shoulder arranged axially between the first and second sections, the shoulder having a first frustoconical surface arranged at a first angle relative to the first radially outward-facing surface and a second frustoconical surface arranged at a second angle relative to the first radially outward-facing surface. This document does not relate to a connector suitable for receiving a hose for securing it within the connector.

[0015] Published U.S. Patent 6,095,572 A discloses a quarter-turn quick-connect assembly for connecting miniature fluid lines, such as hoses, comprising a first connector with radially projecting pins and a second connector located in a rotatable quarter-turn nut with helical grooves that receive the pins. The first connector defines a central passage, and the second connector defines a central passage, each of which can be configured to slidably receive a hollow tube assembly or to screw in a matching male-threaded connector. The quarter-turn quick-connect assembly can be configured to be mounted at the end of a column and may include an adapter that receives a protective column or a frit for filtering the fluid flowing through the quarter-turn assembly.The quarter-turn quick-connect fitting is assembled by pushing the pins of the first fitting into the grooves of the quarter-turn nut and turning the quarter-turn nut approximately 90 degrees relative to the first fitting, which securely seats the pins in the defined angular ranges at the ends of the grooves.

[0016] The published international patent application WO 2019 / 234261 A2 discloses a method for connecting a suction hose for body fluids to a container, comprising the steps of: - providing a hose adapter arranged on a hose section, a seal with at least one annular sealing surface, and a container on which a hose adapter counterpart is arranged; - establishing mechanical contact between a first contact surface provided on the hose adapter, the seal with at least one annular sealing surface, and a second contact surface provided on the hose adapter counterpart in a first orientation of the hose adapter relative to the hose adapter counterpart; and - rotating the hose adapter from the first orientation to a second orientation.so that, through an interaction between sections of the hose adapter and sections of the hose adapter counterpart, the seal with at least one annular sealing surface is squeezed between the first contact surface and the second contact surface, as well as a suction hose for such a method and a quick-connect hose connector that can be used therein.

[0017] The published International Patent Application WO 00 / 25844 A1 discloses an improved pump for the controlled delivery of fluids, the pump comprising a reservoir and a movable piston. A plunger is in releasable contact with the movable piston. A motor is coupled to a drive element, e.g., a drive spindle, in a ready-to-operate manner. The motor is arranged in series with the drive element and the plunger. The drive element is functionally connected to the plunger and arranged such that it is substantially enclosed by the plunger when the plunger is in at least one position. The drive element is designed to move the plunger forward in response to the operation of the motor.

[0018] Published US patent US 9,839912 B2 discloses an analytical device for the automated determination of a measurand in a liquid sample, comprising: a base module; an interchangeable cassette that can be connected to the base module and has at least one liquid container that can be connected to a measuring cell via a liquid line and contains a reagent to be added to the liquid sample to form a measuring liquid; and a transmitter for acquiring measured values ​​correlated with the measurand for the measuring liquid contained in the measuring cell. The cassette has a fluid coupling device associated with the at least one liquid container, comprising a primary part and a secondary part, which serves to establish a connection between the fluid line and the liquid container.

[0019] The published German patent application DE 10 2017 102 052 A1 discloses a plug connection arrangement for detachably connecting a connector of a hydraulic line to a port of a hydraulic system and a method for doing so. A receptacle with at least two hooks is formed at a free end of the port. In the connected state, a curved structure of the hooks interacts with a flexible clip of the connector. A rigid tab of the connector then engages behind each hook of the port. BRIEF DESCRIPTION OF THE INVENTION

[0020] The present invention provides a hose coupling for a fluidic connection in an analysis system, comprising a plug, a socket comprising a first hollow cylinder, the channel of which is connected at one end to a hose and the other end of which comprises a first opening for receiving the plug, wherein the end for receiving the plug is at least partially surrounded by a retaining ring with a recess, wherein the first opening of the socket for receiving the plug extends on one side into a second opening which continues as a channel running along the radius of the first hollow cylinder of the socket;and the connector with a base plate from which a second hollow cylinder extends, the second hollow cylinder having a hook arranged at the end opposite the base plate and extending radially outwards, the second hollow cylinder being configured such that it can be inserted at least partially into the opening of the socket, and the hook engaging behind the retaining ring of the socket to secure the connector against linear movement during a rotational movement, the base plate of the connector having a projection with an edge which, during a rotational movement, engages in the recess of the retaining ring of the socket to secure the connector against rotation.

[0021] In a further embodiment, a flange with an end face is arranged between one end of the hose and the inside of the first hollow cylinder of the sleeve.

[0022] Furthermore, the present invention comprises a hose coupling in which the flange is firmly connected to the hose to prevent the hose from being pulled out of the socket.

[0023] It is also provided that the second hollow cylinder of the plug has a seal on its end face.

[0024] In another embodiment, the seal can be made of an elastic material.

[0025] Another aspect of the invention relates to the seal, which can be an O-ring or a flat seal.

[0026] In a further embodiment of the hose coupling according to the present invention, the first hollow cylinder has a handle on the side opposite the retaining ring, with a grip surface extending radially outwards.

[0027] Another object of the present invention relates to a method for connecting a sleeve and a plug to create a fluidic connection, comprising the steps Providing a sleeve comprising a first hollow cylinder, the channel of which is connected at one end to a hose and the other end of which comprises a first opening for receiving a plug, wherein the end for receiving the plug is at least partially surrounded by a retaining ring with a recess, wherein the first opening of the sleeve for receiving the plug extends on one side into a second opening which continues as a channel running along the radius of the first hollow cylinder of the sleeve;Inserting the plug with a base plate from which a second hollow cylinder extends, the second hollow cylinder having a hook arranged at the end opposite the base plate and extending radially outwards, the second hollow cylinder being configured such that it can be inserted at least partially into the first opening of the socket and the hook being configured such that it can be inserted completely into the second opening of the socket and, in the event of a rotational movement, the hook engages behind the retaining ring of the socket to secure the plug against linear movement, the base plate of the plug having a projection with an edge which, in the event of a rotational movement, engages in the recess of the retaining ring of the socket to secure the plug against rotation, into the socket;Rotating the plug in the socket to secure it against linear movement using the locking ring. Rotating the plug in the socket until the edge of the base plate engages in the recess of the locking ring to secure the plug against rotation.

[0028] Further aspects, features, and advantages of the present invention will readily become apparent from the following detailed description, which simply presents preferred embodiments and implementations. The present invention can also be realized in other and different embodiments, and its various details can be modified in various obvious aspects without departing from the teaching and scope of the present invention. Accordingly, the drawings and descriptions are to be regarded as illustrative and not as limiting. Additional problems and advantages of the invention are partly set forth in the following description and partly become apparent from the description or can be deduced from the embodiment of the invention. SHORT DESCRIPTION OF THE CHARACTERS

[0029] The invention is described in more detail below with reference to the figures. It is obvious to those skilled in the art that these are only possible embodiments, and the invention is not limited to the embodiments shown. FIG. 1 shows a perspective view of both parts of the hose connection before the plug is inserted into the socket. FIG. 2 shows a perspective view of both parts of the hose connection with the plug inserted, but the connection is not yet secured or closed. FIG. 3 shows a perspective view of both parts of the hose connection with the plug inserted in a secured or closed connection. FIG. 4 shows a side view of both parts of the hose connection in the connected and secured state. FIG. 5 The image shows a perspective view of a plug with a hook before it is inserted into the socket. FIG. 6 shows a cross-sectional drawing through both parts of the hose connection in the closed, secured state. FIG. 7 shows a hose coupling according to the invention on a pipette. DETAILED DESCRIPTION OF THE INVENTION

[0030] The previously formulated problem of the invention is solved by the features of the independent claims. The dependent claims cover further specific embodiments of the invention.

[0031] The present invention provides a hose coupling for use in fluidic connections in analytical systems. Its use in an analytical system is characterized by the fact that the hoses have a maximum outer diameter of 10 mm. The hose coupling essentially consists of a socket and a plug, both parts of which are novelly shaped to ensure a secure connection. Furthermore, both parts have features that provide visual feedback on the condition of the connection.

[0032] In the context of the description of the invention, the sleeve is also referred to as the outer component or outer part. The plug is also referred to as the inner part or inner part. The plug can also be part of or a connection of a device. The connected state refers to a state in which the inner part is located inside the outer part. The inner and outer parts are brought into a connected, secured state by a rotational movement.

[0033] FIG. 1 Figure 1 shows a perspective view of the hose connection with socket 1 and plug 50 before the plug 50 is inserted into the socket 1. The plug 50 has a hook 51 which is inserted into opening 10 of the socket 1. Furthermore, the plug 50 has a hollow cylinder 52 with a central channel (not visible) for receiving fluids.

[0034] FIG. 2 Figure 1 shows the state when the plug 50 with hook 51 is inserted into socket 1 or opening 10. Furthermore, when both parts 1 and 50 are connected, the hollow cylinder 52 is partially inserted into the hollow cylinder 2 of socket 1 (see Figure 2). FIG. 6 The two parts, 1 and 50, are in FIG. 2 but has not yet been brought into a closed, secured state by a rotational movement.

[0035] FIG. 3 Figure 1 shows a perspective view of the hose connection with both parts 1 and 50 in the connected, secured state. The sleeve 1 essentially consists of a hollow cylinder 2 with a handle 5 in the form of a surface 7 extending radially from the outside of the cylinder. The position of the surface 7 in relation to the base plate 57 of the connector 50 indicates whether the two parts 1 and 50 are in a connected, secured state. FIG. 7 , left part) or whether the plug 50 is only inserted into the socket 1 without a secure connection being made by a turning movement ( FIG. 7 , right part). The hollow cylinder 2 of sleeve 1 of the hose coupling is firmly connected to a hose 20.

[0036] The hollow cylinder 2 of sleeve 1 has a retaining ring 9 at its open end for receiving the plug 50, which partially surrounds this end and is located on the opposite side of the hose connection with respect to the outer circumference of the hollow cylinder 2. The retaining ring 9 has a recess 91 in the direction of the plug 50 (see figure). FIG. 5 ), which in the connected secured state ( FIG. 3 ) engages on the projection 54 of the edge 55 of the plug 50 (cf. FIG. 4 Recess 91 is flanked on one side by projection 92, which allows projection 54 to engage in recess 91 to achieve a firm but reversible connection (see also FIG. 5 The projection 92 prevents the connection from unintentionally loosening, as it rests against the edge 55 of the projection 54, and hook 51 prevents further rotation. Thus, the connection is firmly but reversibly fixed by the combination of projection 92 and hook 51.

[0037] Hook 51 of plug 50 is rotated by the rotary movement in front of locking surface 56, so that the hook is at the end of channel 15 (cf. FIG. 3 ) is surrounded on three sides of the channel, so that hook 51 can no longer be pulled out of socket 1, thus preventing the plug 50 from being pulled out of socket 1 altogether. Furthermore, after rotation, hook 51 exerts contact pressure between the sealing surface or a flat gasket and the O-ring in front of the locking surface 56, compressing the O-ring and thus ensuring a secure seal.

[0038] FIG. 5 Figure 50 shows a perspective view of plug 50 with hook 51 before it is inserted into the socket. It is evident that cylinder 59 can also have a different geometric shape to indicate the connection status of both parts.

[0039] FIG. 6 Figure 1 shows a cross-section of socket 1 and plug 50 in the connected and secured state. The socket 1 is connected to a hose 20 at the end opposite the end connected to plug 50. A flange 22 is arranged between the hose end 21 and the hollow cylinder 2 of the socket 1. The end face 221 of the flange serves as a sealing surface for an elastic seal 58 in the end face 521 of the hollow cylinder 52 of plug 50. An embodiment with flange 22 and elastic seal 58 ensures a reliable seal at the transition from hose 20 to the channel 53 of the hollow cylinder of plug 50. A further advantage of the flange is that it prevents the hose from twisting when the connection is closed.

[0040] FIG. 7 Figure 3 shows a hose coupling according to the present disclosure as part of a pipette 30. In this specific application example, it is advantageous if a user can immediately recognize from the position of surface 7 whether the connection is in a fixed, secured state or is open. In the left part of FIG. 7 The connection is firm and secure. In the right part of FIG. 7 If surface 7 is twisted or angled, then the connection is not secure in the sense that it is tight.

[0041] The advantages of a hose connection according to the present invention can be summarized as follows: Unlike a threaded screw connection, the connection between the parts is independent of a tightening torque. The position of the socket and plug relative to each other, or the position of the flag on the socket, directly indicates whether the connection is open or closed. Sockets and plugs can be manufactured using simple processes, such as injection molding. The closed connection is mechanically secured.

[0042] The foregoing description of the preferred embodiment of the invention is given for illustrative and descriptive purposes. It is not intended to be exhaustive or to limit the invention precisely to the disclosed form. Modifications and variations are possible in light of the above teaching or may be obtained from practical application of the invention. The embodiment was chosen and described to explain the principles of the invention and its practical application, enabling those skilled in the art to use the invention in various embodiments suitable for the specific intended use. The scope of the invention is defined by the accompanying claims. REFERENCE MARK

[0043] 1 Socket 2 Hollow cylinder socket 5 Handle 7 Surface 9 Retaining ring 10 Opening 15 Channel 20 Hose 21 Hose end 22 Flange 221 End face flange 30 Pipette 50 Plug 51 Hook 52 Hollow cylinder plug 53 Channel hollow cylinder 54 Projection 55 Edge 56 Locking surface 57 Base plate 58 Seal 59 Cylinder 91 Recess retaining ring 92 Projection 521 End face hollow cylinder

Claims

1. A hose coupling for a fluidic connection in an analyser system, comprising - a plug (50); - a sleeve (1) which comprises a first hollow cylinder (2) whose channel (15) is connected at one end (21) to a hose (20) and whose other end comprises a first opening (10) for receiving the plug (50), wherein the end for receiving the plug (50) is at least partially surrounded by a retaining ring (9) with a recess, wherein the first opening (10) of the sleeve (1) for receiving the plug (50) extends on one side into a second opening which continues as a channel (15) extending along the radius of the first hollow cylinder (2); and - the plug (50) with a base plate (57), from which a second hollow cylinder (52) extends, which has a hook (51) arranged at the end opposite the base plate (57), which hook extends radially outwards, wherein the second hollow cylinder (52) is configured in such a way that it can be at least partially inserted into the first opening (10) of the sleeve (1) and the hook (51) is configured in such a way that it can be completely inserted into the second opening of the sleeve (1) and, during a rotary movement, the hook (51) can be inserted behind the securing ring (9) of the sleeve (1) to secure the plug (50), that it can be inserted completely into the second opening of the sleeve (1) and, during a rotary movement, the hook (51) engages behind the retaining ring (9) of the sleeve (1) to secure the plug (50) against linear movement, wherein the base plate (57) of the plug (50) has a projection (54) with an edge (55) which, during a rotary movement, engages in the recess (91) of the retaining ring (9) of the sleeve (1) to secure the plug (50) against twisting.

2. The hose coupling according to claim 1, wherein a flange (22) with an end face (221) is arranged between one end of the hose (20) and the inside of the first hollow cylinder (2) of the sleeve (1).

3. The hose coupling according to claim 1 or 2, wherein the flange (22) is firmly connected to the hose (20) to prevent the hose (20) from being pulled out of the sleeve (1).

4. The hose coupling according to any one of claims 1 to 3, wherein the second hollow cylinder (52) of the plug (50) has a seal (58) on its end face (521).

5. The hose coupling according to claim 4, wherein the seal (58) is made of a resilient material.

6. The hose coupling according to claim 4 or 5, wherein the seal (58) is an O-ring or a flat seal.

7. The hose coupling according to any one of claims 1 to 6, wherein the first hollow cylinder (2) has a handle (5) with a radially outwardly extending gripping surface on the opposite side to the retaining ring (9).

8. A method of connecting a sleeve (1) and a plug (50) to create a fluidic connection, comprising the steps of - Providing a sleeve (1) which comprises a first hollow cylinder (2) whose channel (15) is connected at one end to a hose (20) and whose other end comprises a first opening (10) for receiving a plug (50), wherein the end for receiving the plug (50) is at least partially surrounded by a retaining ring (9) with a recess, wherein the first opening (10) of the sleeve (1) for receiving the plug (50) extends on one side into a second opening which continues as a channel (15) extending along the radius of the first hollow cylinder (2) of the sleeve (1); - Insertion of the plug (50) with a base plate (57), from which a second hollow cylinder (52) extends, which has a hook (51) arranged at the end opposite the base plate (57), which hook extends radially outwards, wherein the second hollow cylinder (52) is configured in such a way that it can be inserted at least partially into the first opening (10) of the sleeve (1) and the hook (51) is configured in such a way that it can be inserted completely into the second opening of the sleeve (1) and, during a rotary movement, the hook (51) can be inserted behind the securing ring (9) of the sleeve (1) to secure the plug against linear movement, that it can be inserted completely into the second opening of the sleeve (1) and, during a rotary movement, the hook (51) engages behind the retaining ring (9) of the sleeve (1) to secure the plug against linear movement, wherein the base plate (57) of the plug (50) has a projection (54) with an edge (55) which, during a rotary movement, engages in the recess of the retaining ring (9) of the sleeve (1) to secure the plug (50) against twisting; - Rotation of the plug (50) in the sleeve (1) to secure the plug (50) against linear movement by means of the retaining ring (9); - Turn the plug (50) in the sleeve (1) until the edge (55) of the base plate engages in the recess of the retaining ring (9) to secure the plug (50) against twisting.