A connection interface for fixedly receiving an HVAC device block method of manufacture of a connection interface, an HVAC field device and of an HVAC field device

Abstract

A connection interface (1) for fixedly receiving an HVAC device block (20), comprising a frame (10) with a first surface (10A), a second surface (10B) opposite the first surface (A); an opening (12) through the first surface (10A) and the second surface (10B) and a circumferential groove (14) in the first surface (10A) surrounding the opening (12). A plurality of reverse-locking mating elements (181-n) are distributed around an outer circumference (13) of the opening (12) configured to engage with complementary reverse-locking mating elements (281-n) of the HVAC device block (20). A seal (16) is arranged in the circumferential groove (14). The connection interface (1) further comprises a plurality of damping elements arranged around an outer circumference (13) of the opening (12), the plurality of damping elements extending - in a direction parallel to the assembly direction (A) - beyond the second surface (10B).

Description

[0001] A CONNECTION INTERFACE FOR FIXEDLY RECEIVING AN HVAC DEVICE BLOCK METHOD OF MANUFACTURE OF A CONNECTION INTERFACE, AN HVAC FIELD DEVICE AND OF AN HVAC FIELD DEVICE

[0002] FIELD OF THE DISCLOSURE

[0003] The present disclosure relates to a connection interface, specifically to a connection interface for fixedly receiving a Heating, Ventilation and Air Conditioning (HVAC) device block. The present further disclosure relates to an HVAC device block. The present disclosure even further relates to an HVAC field device comprising multiple HVAC device blocks. Furthermore, the present disclosure relates to a method of manufacturing of a connection interface, a method of manufacturing an HVAC device block comprising a connection interface as well as to a method of manufacturing an HVAC field device.

[0004] BACKGROUND OF THE DISCLOSURE

[0005] Due to the fact that individuals reportedly spend approximately 90% of their time in indoor environments, Heating, Ventilation, and Air Conditioning (HVAC) systems have assumed a crucial role in everyday life and have a significant impact on people's well-being and comfort. HVAC systems in the field of Heating, Ventilation, and Air Conditioning usually encompass a fluid transportation system that comprises one or more fluid transportation circuits, with at least one of the fluid transportation circuits being coupled to a heat exchanger designed to facilitate the transfer of thermal energy to or from the environment to be regulated via a fluid that circulates within the fluid transportation system.

[0006] To regulate the flow of fluid to or from the heat exchanger and hence control the quantity of thermal energy transferred, the heat exchanger is connected to the fluid transportation system through one or more regulating devices, such as valves and dampers. The regulating devices are actuated by HVAC field devices, in particular, HVAC actuators that include motorized HVAC actuators coupled to the regulating device(s). In the realm of HVAC, HVAC actuators typically consist of an electric motor, which is mechanically coupled (via gears and / or other mechanical coupling) to the actuated part, i.e., the regulating device. The HVAC actuators are electrically controlled by HVAC controllers, specifically an electronic circuit of HVAC controller(s). Additionally, various HVAC sensors may be utilized to assess environmental parameters like humidity, temperature, CO2 or dust particle levels. Furthermore, HVAC sensors may be employed to ascertain operational parameters of various components of an HVAC system, such as the actuated position of an actuated part, the operational state of an HVAC actuator (e.g., online / standby / offline), operating temperature, error state, etc.

[0007] HVAC systems commonly comprise an HVAC controller configured to generate control signals) for operating the HVAC actuator(s) and / or process signals from the HVAC sensors. In typical HVAC applications, the HVAC controller(s) generate the control signals for the HVAC actuators according to various control algorithms (e.g. with regards to differential pressure, room temperature, flow of energy, etc.) to thereby actuate the actuators, such as to open and close a damper or an orifice of a valve to regulate the flow of fluid.

[0008] Certain control functions of HVAC systems may be performed from a remote server arranged remote from the controlled environment, the remote server comprising a computer program such as a Building Management System (BMS) to control and monitor a building’s mechanical and electrical equipment. Furthermore, certain functions, in particular the commissioning and / or configuration of HVAC systems may be performed by means of portable devices, such as a general purpose mobile computing device (e.g. a smartphone, tablet, laptop, etc.) or a dedicated configuration tool.

[0009] In summary, devices of HVAC systems may be categorized into two categories by their location with respect to the controlled environment: remote devices (arranged remotely from the controlled environment) and field devices (located within the controlled environment or mechanically connected, e.g. by the fluid transportation system, to the controlled environment). Field devices implement one or more electrical and / or mechanical functions and / or other functions (e.g. hydraulic, optical) and comprise - but not limited to - actuators, sensors, or a combination thereof.

[0010] HVAC field devices are devices hydraulically and / or mechanically connectable to at least part of the fluid transportation circuit(s) with fluid supply / return lines, such as pipes, ducts or ports of valves and / or dampers such as to regulate and / or measure parameters of fluid(s) flowing therethrough, parameters such as flow rate, temperature, humidity, pressure, viscosity and / or chemical composition. Alternatively, or additionally, HVAC field devices are connectable to other HVAC field device(s) such as to control and / or measure parameters thereof, such as valve position, as well as speed, current and voltage of actuator(s), as well as positions of flow regulating devices, such as valves and / or dampers, etc.

[0011] HVAC field devices for regulating flow (parameters) of fluid(s) are referred to as HVAC actuators. HVAC actuators typically comprise a motor, such as an electric motor, and a mechanical drive for drivingly connecting the electric motor to an actuated part such as a valve or damper. HVAC actuators typically further comprise an interface for receiving electrical power; control and / or configuration signals.

[0012] HVAC field devices for measuring parameters of fluid(s) are referred to as HVAC sensors. Furthermore, the term HVAC field device also encompasses HVAC field devices combining sensor and actuator functions, for both controlling and measuring parameters of fluid(s) or other HVAC field device(s).

[0013] With increasing complexity of HVAC systems, there is an ever increasing demand for a wide variety of field devices implementing various electrical and / or mechanical and / or thermal HVAC functions and / or other functions (e.g. hydraulic, optical). Even for the same function, a range of HVAC field devices are required to cover a wide array of use cases each characterized by different parameters. For example, for the mechanical function of actuating a valve or a damper, different variants of a certain type of HVAC actuator are required to cover a wide range of flow regulation by means of valves of different sizes, requiring different actuation forces (e.g. a torque ranging from 1 Nm up to 160 Nm or even more). Different variants of HVAC actuators are also required to cover different power supplies and also different actuation times. Furthermore, the nature of the controlled environment also leads to varying demands on the HVAC field devices. For example, special variants of HVAC field devices are needed to be suitable for use in harsh environments. In addition, depending on the architecture of the HVAC system, various variants of HVAC field devices are needed to cover the different types of connectivity requirements.

[0014] An effective approach for covering a wide range of HVAC field devices is made possible through modularization, whereby the functionality(s) of an HVAC field device is extended by the attachment of one or more add-on devices. This allows the same add-on devices to be deployed with different HVAC field devices but also the same HVAC field device to be used in combination with various add-on devices. For example, the same add-on device comprising a communication interface (e.g. a wired or wireless data communication interface) may be attached to a sensor kind HVAC field device and / or an actuator kind HVAC field device. As a further example, the same HVAC field device of the sensor kind may be used in combination with an add-on device comprising a wired communication interface or another add-on device with a wireless communication interface without the need to design, manufacture respectively maintain separate wireless and wired versions of the HVAC field device.

[0015] With increasing demand for modularization of HVAC field devices come increased demands for solutions to reliably, efficiently and flexibly connect HVAC device blocks.

[0016] SUMMARY OF THE DISCLOSURE

[0017] According to the present disclosure, modularization is facilitated by a connection interface for fixedly receiving an HVAC device block. It is hence an object of this disclosure to provide a connection interface for fixedly receiving an HVAC device block, which connection interface does not have at least some of the disadvantages of the prior art.

[0018] In particular, it is an object of embodiments disclosed to provide a connection interface enabling ease of assembly of an HVAC device block comprising a connection interface for fixedly receiving an HVAC device block.

[0019] According to the present disclosure, these objects are addressed by the features of independent claim 1. In addition, further advantageous embodiments follow from the dependent claims and the description.

[0020] In particular, these objects are addressed by a connection interface for fixedly receiving an HVAC device block in an assembly direction, the connection interface comprising a frame, a plurality of reverse-locking mating elements, a seal and a plurality of damping elements. The frame has a first surface facing and orthogonal to the assembly direction, in particular an essentially flat first surface. Furthermore, the frame has a second surface opposite the first surface, in particular an essentially flat second surface. The frame comprises an opening through the first surface and the second surface. A circumferential groove is provided in the first surface of the frame, the circumferential groove surrounding the opening.

[0021] The plurality of reverse-locking mating elements are distributed around an outer circumference of the opening. According to embodiments, the reverse-locking mating elements are surrounded by the circumferential groove. Alternatively, or additionally, the reverse-locking mating elements are distributed outside the circumferential groove. The reverse-locking mating elements are configured to engage with complementary reverse-locking mating elements of the HVAC device block. In particular, reverse-locking mating elements are configured to engage with complementary reverse-locking mating elements of the HVAC device block when the HVAC device block is joined with the connection interface in the assembly direction. The seal is arranged in the circumferential groove, the seal hence also surrounding the opening.

[0022] The plurality of damping elements are arranged around an outer circumference of the opening, the plurality of damping elements extending beyond the second surface. The plurality of damping elements extend in a direction parallel to the assembly direction. The damping elements advantageous as they are able to absorb vibrations between the connection interface and a printed circuit board of an HVAC device block upon the connection interface being joined with a housing of the HVAC device block.

[0023] According to embodiments, through-channels are provided within the frame, the through- channels connecting the circumferential groove with the second surface of the frame. The plurality of damping elements comprise a plurality of protrusions integral to the seal, the plurality of protrusions are arranged in the through-channels and extend from the circumferential groove through the frame beyond the second surface. The plurality of protrusions each comprise damping surfaces, in particular damping surfaces facing opposite the assembly direction.

[0024] According to embodiments, the seal and its plurality of protrusions is injection-molded as a single piece into the circumferential groove and the through-channels, respectively.

[0025] According to embodiments, the plurality of damping elements comprise a plurality of elastic elements integral to the frame, the plurality of elastic elements protruding from the second surface of the frame in a direction parallel to the assembly direction.

[0026] According to embodiments, the connection interface further comprises a light guide integrated into the frame. The light guide is configured and arranged to guide a light beam between a first end and a second end of the light guide. The first end of the light guide is arranged on an inner surface of the frame facing the opening, while the second end is arranged on an outer peripheral surface of the frame facing away from the frame. The light guide is advantageous as it enables external visual inspection of a visual indicator, such as an LED, arranged on a printed circuit board of an HVAC device block - the printed circuit board being surrounded by the frame when the frame is joined with a housing of the HVAC device block.

[0027] According to embodiments, the light guide is integral to the frame and made from a transparent material exhibiting a high optical clarity and minimal internal absorption or scattering to ensure efficient light transmission, such as acrylic Polymethyl Methacrylate (PMMA) or polycarbonate (PC) depending on the application's requirements.

[0028] According to embodiments, the first end of the light guide is configured to capture the light beam from a first light direction orthogonal to the second surface of the frame. The light guide has a curved shape, configured to deflect (e.g. by internal refraction) the light beam from the first light direction into a second light direction parallel to the first surface of the frame. Furthermore, the second end of the light guide is configured to dissipate the light beam in the second light direction.

[0029] According to embodiments, the light guide includes features like ridges, notches, or a patterned surface to control the light's path within the light guide. According to embodiments, the light guide has a refractive index that varies across its diameter, known as a gradient index (GRIN) lens.

[0030] According to embodiments, to enhance the light guiding efficiency, certain surface treatments can be applied. These could include anti-reflective coatings, diffusing agents, or mirror coatings on strategic sections of the light guide to manipulate light propagation.

[0031] According to embodiments, the second end is designed to spread light in a particular pattern or directionality or to couple light into another optical system or detector. The second end may also be shaped or have optical elements such as lenses that control the divergence or focus of the light as it leaves the guide. The objective of embodiments of the light guide is to ensure that light does not exit the frame in a concentrated, point-like manner but is instead dispersed across the corner. For example, the light is to be emitted both upward and downward at an angle of at least ±45° so that the illumination remains visible from below and / or above. These objectives are addressed according to embodiments in that the light guide comprises a curved surface having a channel with a three-dimensional profile. According to embodiments, the channel has a delta-shaped cross-section in the direction of the first surface. Additionally, or alternatively, upperand lower surfaces of the light guide are provided with a structured pattern comprising concave and convex elements to expand vertical light components, thereby increasing the visibility of the emitted light from multiple viewing angles.

[0032] According to embodiments, the reverse-locking mating elements of the connection interface each comprise a deflection surface and a latching surface. The deflection surface is arranged at an angle greater than 0° and less than 90° with respect to the assembly direction. The deflection surface is configured to deflect a flexible part of a complementary reverse-locking mating element upon the HVAC device block being brought into contact with the connection interface in the assembly direction. The latching surface is arranged transversal to the assembly direction and configured to retain a retainer part disposed at a distal end of the complementary reverse-locking mating element once the distal end of the complementary re- verse-locking mating element passes a distal end of the deflection surface.

[0033] According to embodiments, the deflection surface of each reverse-locking mating element comprises a gap portion for allowing penetration of needles of a removal tool to deflect the flexible parts of the complementary reverse-locking mating elements.

[0034] According to embodiments, the connection interface comprises one or more alignment elements arranged on the frame to align the HVAC device block when brought into contact with the connection interface in the assembly direction. In particular, the alignment elements comprise alignment surfaces tapered in the assembly direction. According to embodiments, the frame of the connection interface comprises stiffening elements arranged to mechanically stabilize the frame, in particular with respect to torsional forces transversal to the assembly direction.

[0035] According to embodiments, the connection interface 1 comprises an extension surface arranged outside the circumferential groove.

[0036] According to embodiments, the frame of the connection interface is made of a transparent material, in particular a polycarbonate such as a polycarbonate resin for injection molding, in particular a flame-retardant polycarbonate resin (e.g. Lexan CFR7630). According to embodiments the seal including its plurality of protrusions is made of an elastic material such as a thermoplastic elastomer (e.g. Krailburg Thermolast, also known as THERMOLAST® K).

[0037] It is a further object of this disclosure to provide an HVAC device block configured for fixedly receiving a (further) HVAC device block, which HVAC device block does not have at least some of the disadvantages of the prior art.

[0038] According to the present disclosure, these objects are addressed by an HVAC device block comprising a housing and a connection interface according to one of the embodiments disclosed herein, a printed circuit board, accommodating an electronic circuit, being arranged within the housing. The connection interface is joined with the housing by welding a circumferential ridge, arranged on the second surface of the frame opposite the first surface, with a corresponding circumferential edge of the housing.

[0039] According to embodiments, in order cover / seal sections of the HVAC device block extending beyond the circumferential groove of the connection interface, the frame of the connection interface is provided with an extension surface extending beyond the circumferential groove. In order to ensure compatibility of HVAC device blocks having housings of various dimensions, the connection interface is provided with frames having different dimensions of the extension surface while the circumfe rential groove has a fixed, well defined geometry.

[0040] Upon joining of the connection interface with the housing, the damping elements are brought into contact with the printed circuit board to thereby secure the printed circuit board.

[0041] According to embodiments, in order to enable the HVAC device block to be attached to a connection interface - of a further HVAC device block, a plurality of complementary reverselocking mating elements are arranged on the housing. According to embodiments, the complementary reverse-locking mating elements each comprise a flexible part configured to deflect upon being brought into contact, in the assembly direction, with the deflection surface of the connection interface and a retainer part disposed at a distal end of the complementary reverse-locking mating element and configured to engage with the latching surface of the reverse-locking mating elements once the distal end of the complementary reverse-locking mating element passes a distal end of the deflection surface. The term “complimentary” with regards to the complementary reverse-locking mating elements, shall be understood as the complementary reverse-locking mating elements of the HVAC device block being compatible to engage and interlock with the reverse-locking mating elements of the connection interface.

[0042] According to embodiments, the connection interface is joined with the housing by ultrasonic welding. Alternatively, or additionally, the connection interface is joined with the housing by laser welding.

[0043] According to embodiments, the printed circuit board of the HVAC device block comprises a light source, the light source being directed such as to emit light in the first light direction of the light guide of the connection interface. According to embodiments, the printed circuit board of the HVAC device block comprises openings to allow needles of a removal tool to penetrate through the printed circuit board for deflecting the flexible parts of the complementary reverse-locking mating elements.

[0044] According to embodiments, the reverse-locking mating elements each comprise a gap portion in the deflection surface and / or the latching surface to allow needles of a removal tool to come into contact with and to deflect the flexible parts of the complementary reverse-locking mating elements. Provision of gap portions in the deflection surfaces of the reverse-locking mating elements is advantageous as they enabled a non-destructive disassembly of an HVAC field device by removal of HVAC device blocks from the connection interface of the adjacent HVAC device block. The non-destructive disassembly of an HVAC field device is made possible by a dedicated removal tool having needles specifically arranged corresponding to circumferential arrangement of the reverse-locking mating elements distributed around an outer circumference of the opening. Furthermore, provision of the gap portions in the deflection surfaces of the reverse-locking mating elements for non-destructive disassembly of an HVAC field device is advantageous as the HVAC field device cannot be accidentally or maliciously disassembled, whereby any forced attempt to dissemble the HVAC field device without the use of the dedicated removal tool leading to visible traces or manipulation.

[0045] The present disclosure further relates to an HVAC field device comprising a first HVAC device block and a second HVAC device block according to one of the embodiments disclosed herein, the first HVAC device block being fixedly attached on top of the second HVAC device block, by engagement of the plurality of complementary reverse-locking mating elements arranged on the bottom of the first HVAC device block with the plurality of reverse-locking mating elements of the connection interface of the second HVAC device block.

[0046] The present invention further relates to a method of manufacturing a connection interface for fixedly receiving an HVAC device block in an assembly direction. In a first step of the method of manufacturing a connection interface, a frame is provided having an opening, a circumfer- ential groove on a first surface of the frame orthogonal to the assembly direction, the circumferential groove surrounding the opening, and having a plurality of reverse-locking mating elements distributed around an outer circumference of the opening, the reverse-locking mating elements being configured to engage with complementary reverse-locking mating elements of the HVAC device block.

[0047] Thereafter, a seal is injection molded into the circumferential groove. Furthermore, a plurality of damping elements are provided, arranged around an outer circumference of the opening, the plurality of damping elements extending - in a direction parallel to the assembly direction - beyond a second surface of the frame opposite the first surface.

[0048] According to embodiments, the method of manufacturing a connection interface further comprises providing a plurality of through-channels connecting the circumferential groove with the second surface of the frame. The plurality of damping elements are, in this embodiment, provided by injection molding, into the plurality of through-channels of the circumferential groove, a plurality of protrusions as damping elements integral with the seal, such that the plurality of protrusions extend through the frame beyond the second surface of the frame. Alternatively, or additionally, a plurality of elastic elements (integral to the frame?) are provided as damping elements.

[0049] According to embodiments, the method of manufacturing a connection interface further comprises integrating a light guide into the frame. The light guide is configured and arranged to guide a light beam between a first end arranged on an inner surface of the frame and a second end arranged on an outer peripheral surface of the frame.

[0050] The present disclosure further relates to a method of manufacturing an HVAC device block. In a first step of the method of manufacturing an HVAC device block, a connection interface is manufactured according to any one of the embodiments disclosed herein. Furthermore, a housing is provided, a printed circuit board accommodating an electronic circuit being ar- ranged within the housing. Thereafter, a circumferential ridge, arranged on the second surface of the frame opposite the first surface, is welded with a corresponding circumferential edge on the housing, the damping elements being brought into contact with the printed circuit board to thereby secure the printed circuit board.

[0051] According to embodiments, welding the connection interface with the housing comprises welding by ultrasonic welding. Alternatively, or additionally, the connection interface is joined with the housing by laser welding.

[0052] According to embodiments, the method of manufacturing an HVAC device block further comprises the step of providing a plurality of complementary reverse-locking mating elements arranged on the housing, the complementary reverse-locking mating elements each comprising a flexible part configured to deflect upon being brought into contact, in the assembly direction, with the deflection surface of the connection interface, and a retainer part disposed at a distal end of the complementary reverse-locking mating element and configured to the engage with the latching surface of the reverse-locking mating elements once the distal end of the complementary reverse-locking mating element passes a distal end of the deflection surface.

[0053] The present disclosure further relates to a method of manufacturing of an HVAC field device. In a first step of the method of manufacturing of an HVAC field device, a first HVAC device block and a second HVAC device block are manufactured by the method of manufacturing an HVAC device block according to any one of the embodiments disclosed herein. Thereafter, the first HVAC device block is brought into in contact with the second HVAC device block in the assembly direction, thereby causing the plurality of complementary reverse-locking mating elements of the first HVAC device block to engage with the plurality of reverse-locking mating elements of the connection interface of the second HVAC device block to thereby attach the first HVAC device block on top of the second HVAC device block. It is to be understood that both the foregoing general description and the following detailed description present embodiments, and are intended to provide an overview or framework for understanding the nature and character of the disclosure. The accompanying drawings are included to provide a further understanding, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments, and together with the description serve to explain the principles and operation of the concepts disclosed.

[0054] BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The present disclosure will be explained in more detail, by way of example, with reference to the drawings (labeled as “Fig”) whereby:

[0056] Figure 1 shows a perspective view of a connection interface according to the present disclosure;

[0057] Figure 2 shows a perspective cross-sectional view of a connection interface according to the present disclosure;

[0058] Figure 3A shows a perspective view of a frame of a connection interface according to the present disclosure;

[0059] Figure 3B shows a perspective view of a seal of a connection interface according to the present disclosure;

[0060] Figure 3C shows a perspective view of a connection interface according to the present disclosure;

[0061] Figures 4A-D illustrate schematically the engagement of reverse-locking mating elements of a connection interface with complementary reverse-locking mating elements arranged on the housing of an HVAC device block; Figures 5A-D illustrate schematically the engagement of reverse-locking mating elements of a connection interface with a further embodiment of complementary re- verse-locking mating elements arranged on the housing of an HVAC device block;

[0062] Figures 6A-D illustrate schematically the disengagement of reverse-locking mating elements of a connection interface from complementary reverse-locking mating elements arranged on the housing of an HVAC device block using a needle of a removal tool;

[0063] Figure 7 illustrates schematically a first embodiment of a seal with integral protrusions as damping elements;

[0064] Figure 8 illustrates schematically a further embodiment of a seal with integral protrusions as damping elements;

[0065] Figure 9A illustrates schematically a first embodiment of a light guide of the connection interface;

[0066] Figure 9B illustrates a magnified view of a further embodiment of a light guide of the connection interface;

[0067] Figures 10A-D illustrate steps of a method of manufacturing an HVAC device block according to the present disclosure;

[0068] Figure 11 illustrates an exploded view of an HVAC field device manufactured according to a method of manufacturing an HVAC field device according to the present disclosure; Figure 12 illustrates an HVAC field device manufactured according to a method of manufacturing an HVAC field device according to the present disclosure;

[0069] Figure 13 illustrates a perspective view of a further embodiment of the connection interface according to the present disclosure, the frame comprising an extension portion;

[0070] Figure 14 illustrates a top view of the connection interface of figure 13, the frame comprising an extension portion;

[0071] Figure 15 illustrates a cross section along the plane AA of the connection interface of Figures 13 and 14; and

[0072] Figure 16 illustrates a further embodiment of the frame of the connection interface comprising a plurality of alignment elements and stiffening elements.

[0073] DETAILED DESCRIPTION OF THE EMBODIMENTS

[0074] It shall be understood that terms “bottom”, “top”, “lower” or “upper” refer an exemplary orientation provided for a better special understanding of the features. These relative terms shall not be interpreted to limit the respective features to a vertical positioning in any stage of production, assembly or installation of the claimed entities.

[0075] Elements provided in plurality are shown and referenced with a numerical index (i,2, 3...n) and referenced collectively with a range of indexes (e.g. i.n).

[0076] As shown on figures 1 and 2, the connection interface 1 comprising a frame 10 having a first surface 10A facing and orthogonal to an assembly direction A - illustrated on the figures with a downwards pointed block arrow. The first surface 10A is an essentially flat first surface 10A, a top surface in view of the orientation of the frame 10 on the figures. Furthermore, the frame 10 has a second surface 10B opposite the first surface 10A, in particular an essentially flat second surface 10B, a bottom surface in view of the orientation of the frame 10 on the figures.

[0077] The frame 10 has an opening 12 through the first surface 10A and the second surface 10B. A circumferential groove 14 is provided in the first surface 10A of the frame 10, the circumferential groove 14 surrounding the opening 12. A circumferential groove 14 is provided in the first surface 10A of the frame 10, the circumferential groove 14 surrounding the opening 12.

[0078] A plurality of reverse-locking mating elements 18i-nare distributed around an outer circumference 13 of the opening 12, the reverse-locking mating elements 18i.nbeing surrounded by the circumferential groove 14. The reverse-locking mating elements 18i-nare configured to engage with complementary reverse-locking mating elements 28-i-nof an HVAC device block 20 when the HVAC device block 20 is joined with the connection interface 1 in the assembly direction A - as it will be described in detail with reference to figures 4A-D, 5A-D and 6A-D.

[0079] A seal 16 is arranged in the circumferential groove 14, the seal 16 hence also surrounding the opening 12.

[0080] As illustrated on figure 2, through-channels 142i.mare provided within the frame 10, the through-channels 142i-mconnecting the circumferential groove 14 with the second surface 10B of the frame 10.

[0081] A plurality of protrusions 16i-mintegral to the seal 16 are provided as damping elements, arranged around an outer circumference 13 of the opening 12. The plurality of protrusions 16i-mextend from the circumferential groove 14 through the frame 10 beyond the second surface 10B. The plurality of protrusions 16-i-meach comprise damping surfaces 162i.m, in particular damping surfaces facing opposite the assembly direction A. The damping elements are provided to absorb vibrations between the connection interface 1 and a printed circuit board 25 of an HVAC device block 20 upon the connection interface 1 being joined with a housing of the HVAC device block 20 - as described with reference to figures 10A-D.

[0082] The seal 16 and its plurality of protrusions 16i.mis injection-molded as a single piece into the circumferential groove 14 and the through-channels 142i.m, respectively.

[0083] As illustrated, the connection interface 1 further comprises a light guide 15 integrated into the frame 10, configured to guide light from within the opening 12 outside of the frame 10.

[0084] Figure 3A shows a perspective view of the frame 10 of the connection interface 1 , illustrating the circumferential groove 14 and the through-channels 142i.mprovided within the circumferential groove 14 as well as the light guide 15 as integral part of the frame 10.

[0085] Figure 3B shows a perspective view of the seal 16 also illustrating the plurality of protrusions 16i-mas integral parts of the seal 16.

[0086] Figure 3C shows a perspective view of the connection interface 1 , whereby the seal 16 with its integral protrusions 16i.mhas been arranged into the circumferential groove 14 of the frame 10.

[0087] Figures 4A-D illustrate schematically the engagement of reverse-locking mating elements 18i-nwith the complementary reverse-locking mating elements 28i.narranged on the housing of an HVAC device block 20. As shown on the front view of figure 4A, the reverse-locking mating elements 18i-neach comprise a deflection surface 186i.nand a latching surface 1881-n, the latching surface 188i.nbeing transversal to the deflection surface 186i.n. Correspondingly, the complementary reverse-locking mating elements 28i.neach comprise a flexible part 283i-nand a retainer part 286i.ndisposed at a distal end of the complementary reverselocking mating element 28i.n. As illustrated on the side view of figure 4B, the deflection surfaces 186i.n- of the reverselocking mating elements 18i-nof the connection interface 1 - are configured to deflect the flexible parts 282i.n- of the complementary reverse-locking mating elements 28i.n- upon being brought into contact in the assembly direction A.

[0088] As shown on figures 4C and 4D, the latching surfaces 188i.n- of the reverse-locking mating elements 18i-nof the connection interface 1 - are configured to retain the retainer parts 286i.ndisposed at distal ends of the complementary reverse-locking mating elements 28-i-nonce the distal ends of the complementary reverse-locking mating elements 28i.npass the corresponding distal ends of the deflection surfaces 186i.n.

[0089] Figures 5A-D illustrate schematically the engagement of a furtherembodiment ofthe reverselocking mating elements 18i_nof the connection interface 1 with a further embodiment of the complementary reverse-locking mating elements 28i.n.

[0090] Turing now to the sequence of Figures 6A-D, the disengagement of reverse-locking mating elements 18i.nfrom complementary reverse-locking mating elements 28i.nusing needles 50 of a removal tool shall be described. As shown on figure 6A, the deflection surface 186i.nof each reverse-locking mating element 18i-ncomprises a gap portion 185i.nfor allowing penetration of a needle 50 of a removal tool. As shown on figure 6B, penetration of the needle 50 - in the assembly direction A - into the gap portion 1851 _ncauses a deflection of the flexible parts 282i-nof the complementary reverse-locking mating elements 28i.n. As visible on figure 6D, the deflection of the flexible parts 282i.nof the complementary reverse-locking mating elements 28i _ninflicted by the needle 50 causes the retainer part 286i.nto disengage from the latching surface 188-i-n, allowing removal of the complementary reverse-locking mating element 28i.nfrom the reverse-locking mating elements 18i-n.

[0091] Figures 7 and 8 illustrates schematically various embodiments of the seal 16 with integral damping elements, provided as protrusions 16i-mintegral to the seal 16, the plurality of protrusions 16i-mextending from the circumferential groove 14 through through-channels 142i_mof the frame 10 beyond the second surface 10B. The plurality of protrusions 16-i-meach comprise damping surfaces 162i.m.

[0092] Figure 9A illustrates schematically a first embodiment of a light guide 15 of the connection interface 1. The light guide 15 is configured and arranged to guide a light beam between a first end 15inand a second end 15out of the light guide 15. The first end 15inof the light guide 15 is arranged on an inner surface 10inof the frame 10 facing the opening, while the second end 15out is arranged on an outer peripheral surface 10out of the frame 10 facing away from the frame 10. The light guide 15 is advantageous as it enables external visual inspection of a light source 27, such as an LED, arranged on a printed circuit board 25 of an HVAC device block 20 - the printed circuit board 25 being surrounded by the frame 10 when the frame 10 is joined with a housing 22 of the HVAC device block 20. The light guide 15 is integral to the frame 10 and made from a transparent material exhibiting a high optical clarity and minimal internal absorption or scattering to ensure efficient light transmission, such as acrylic Polymethyl Methacrylate PMMA or polycarbonate PC depending on the application's requirements. The first end 15inof the light guide 15 is configured to capture the light beam from a first light direction L1 orthogonal to the second surface 10B of the frame 10. The light guide 15 has a curved shape, configured to deflect (e.g. by internal refraction) the light beam from the first light direction L1 into a second light direction parallel to the first surface 10A of the frame 10. Furthermore, the second end 15out of the light guide 15 is configured to dissipate the light beam in the second light direction L2.

[0093] According to an embodiment, the light guide 15 is configured to direct light from the light source 27 mounted on the printed circuit board 25 to an illuminated corner of the frame 10. The geometry of the light guide 15 is such that the light exiting the second end 150Ut provides a corner illumination of the frame 10.

[0094] Figure 9B shows a partial cross section of the frame 10 of a further embodiment of the light guide 15, whereby the light guide 15 comprises a curved surface 15c arranged to cause light incident from the first end 15jnto be reflected within the light guide 15 towards the second end 150ut. The light guide 15, in particular the curved surface 15c is designed to ensure that the light does not exit in a concentrated, point-like manner but is instead dispersed across the corner. Additionally, the light guide (15) is structured to emit light in both upward and downward directions, e.g. at an angle of at least ±45° from the horizontal (surface 10A) to ensure visibility from below and above. As shown on figure 9B, the first end 15jnof the light guide 15 is configured to capture the emitted light in a first light direction L1 , which is orthogonal to the second surface 10B of the frame 10. The light guide 15 then curves at the curved surface 15c, redirecting the light into the second light direction L2, which runs parallel to the first surface 10A of the frame 10 at the second end 15out. Light-emitting surfaces of the frame 10 may be structured to enhance light scattering ensuring uniform illumination. The structured surfaces may include texturing or diffusion patterns that optimize light dispersion. A rougher structuring may be implemented to further improve light diffusion and uniformity.

[0095] The luminance of the illuminated area is selected to achieve optimal visibility. For example, the luminance target may be set between 500 and 1000 cd / m2. The maximum achievable luminance is constrained by available light source power, the size of the illuminated surface, and the angular distribution of emitted light. To achieve optimal light distribution, the light guide 15 is designed to direct light only through designated optical paths while preventing undesired leakage.

[0096] In configurations where the available height of the light guide 15 is relatively small compared to the horizontal transmission distance, the light guide 15 must be configured to ensure that light remains contained within the optical pathway and does not unintentionally exit at intermediate surfaces of the light guide 15. To achieve this, according to embodiments, such as shown on Figure 9B, the light guide 15 includes a channel with a three-dimensional profile (at the curved surface 15c), where the channel has a delta-shaped cross-section in the horizontal direction (second light direction L2). This delta shape facilitates an even distribution of light across the illuminated corner of the frame 10, ensuring uniform emission while minimizing unintended light loss. To further optimize light propagation in the vertical direction, upper and lower surfaces of the light guide 15 may be provided with a structured pattern comprising concave and convex elements. These surface structures serve to expand vertical light components, thereby increasing visibility of the emitted light from multiple viewing angles.

[0097] Figures 10A-D illustrate steps of a method of manufacturing an HVAC device block 20. In a first step of the method of manufacturing an HVAC device block 20, as depicted on figure 10A, a connection interface 1 is provided according to any one of the embodiments disclosed herein. Furthermore, a printed circuit board 25 accommodating an electronic circuit 23 and a light source 27, such as an LED, is provided. The printed circuit board 25 is then fit into a housing 22 of the HVAC device block 20. In order to enable the HVAC device block 20 to be attached to a connection interface 1 - of a further HVAC device block, a plurality of complementary reverse-locking mating elements 28i_n- as described hereinbefore - are arranged on the housing 22.

[0098] As shown on figure 10D, after the printed circuit board 25 is fitted into the housing 22, the connection interface 1 is joined with the housing 22 by welding a circumferential ridge 19, arranged on the second surface 10B of the frame 10 opposite the first surface 10A, with a corresponding circumferential edge 29 of the housing 22. Upon joining of the connection interface 1 with the housing 22, the damping elements (in this embodiment the protrusions 18i-nare brought into contact with the printed circuit board 25 to thereby secure the printed circuit board 25.

[0099] Figure 11 illustrates an exploded view of an HVAC field device 100 manufactured from a cover 30, a first connection interface 1 i, a first HVAC device block 20i, a second connection interface I2 and a second HVAC device block 2O2. This figure illustrates well the benefits of the connection interface 1 of the present disclosure, whereby HVAC device blocks 20i, 2O2 respectively a cover 30 can all be easily assembled by way of a common / standard footprint provided by the connection interface 11 , I2. Figure 12 illustrates the same HVAC field device

[0100] 100 in assembled form. Figure 13 shows a perspective view illustrating a further embodiment of the connection interface 1 , whereby in order cover sections of HVAC device blocks 20 extending beyond the circumferential groove 14 of the connection interface 1 , the frame 10 of the connection interface 1 is provided with an extension surface 19 extending beyond the circumferential groove 14. In order to ensure compatibility of HVAC device blocks 20 having housings 22 of various dimensions, an range of connection interfaces 1 is envisaged, provided with frames 10 having different dimensions of the extension surface 19 while the circumferential groove 14 has a fixed, well defined geometry.

[0101] Figure 14 shows a top view of the connection interface 1 of figure 13, illustrating plane AA corresponding to the cross section of Figure 15.

[0102] Figure 15 illustrates a cross section along the plane AA of the connection interface of Figures 13 and 14, showing the arrangement of the light guide 15 within the extension surface 19 of the frame 10 extending beyond the circumferential groove 14.

[0103] As shown on figure 16, the frame 10 of the connection interface 1 may comprise a plurality of alignment elements 17 arranged on the frame 10 to align the HVAC device block 20 when brought into contact with the connection interface 1 in the assembly direction A. As shown, the alignment elements 17 comprise alignment surfaces tapered in the assembly direction A. Furthermore, the frame 10 may comprise stiffening elements 11 arranged to mechanically stabilize the frame 10, in particular with respect to torsional forces transversal to the assembly direction A. The stiffening elements 11 may be provided as L-shaped and / or straight trusses between adjacent respectively opposing sides of the frame 10.lt should be noted that, in the description, the sequence of the steps has been presented in a specific order, one skilled in the art will understand, however, that the order of at least some of the steps could be altered, without deviating from the scope of the disclosure. REFERENCE LIST connection interface 1 , 11, I2 frame 10, 10i, 2 peripheral surface (of the frame) 10out inner surface (of the frame) 10infirst surface 10A second surface 10B stiffening elements 11 opening 12 outer circumference (of the opening) 13 circumferential groove 14 through-channels (of the circumferential groove) 142-i-mlight guide 15 curved surface (of light guide) 15c first end (of the light guide) 15insecond end (of the light guide) 15out first light direction L1 second light direction L2 seal 16 protrusions (of the seal) 16i.mdamping surfaces (of the protrusions) 162-i-maligning element(s) 17 reverse-locking mating elements 181-n deflection surface (of the reverse-locking mating elements) 186i.nlatching surface (of the reverse-locking mating elements) 188i.nextension surface 19

[0104] HVAC device block 20, 20i, 202complementary reverse-locking mating element 28l-n flexible part 282i.nretainer part 286i.ncover 30

[0105] HVAC device 100 assembly direction A

Claims

CLAIMS1 . A connection interface (1) for fixedly receiving an HVAC device block (20) in an assembly direction (A), the connection interface (1) comprising: a frame (10) comprising: a first surface (10A) facing and orthogonal to the assembly direction (A); a second surface (1 OB) opposite the first surface (A); an opening (12) through the first surface (10A) and the second surface (10B); and a circumferential groove (14) in the first surface (10A) surrounding the opening (12); a plurality of reverse-locking mating elements (18i.n) distributed around an outer circumference (13) of the opening (12); a seal (16) arranged in the circumferential groove (14); a plurality of damping elements arranged around an outer circumference (13) of the opening (12), the plurality of damping elements extending - in a direction parallel to the assembly direction (A) - beyond the second surface (10B).

2. The connection interface (1) according to claim 1 , wherein the plurality of damping elements comprise a plurality of protrusions (16i-m) integral to the seal (16), the plurality of protrusions (16i-m) extending from the circumferential groove (14) through the frame (10) beyond the second surface (10B), the protrusions (16i-m) being arranged in through-channels (142i.m) connecting the circumferential groove (14) with the second surface (10B) of the frame (10), the plurality of protrusions (16i.m) comprising damping surfaces (162i.m).

3. The connection interface (1) according to claim 2, wherein the seal (16) and its plurality of protrusions (16i-m) is injection-molded as a single piece into the circumferential groove (14) and the through-channels (142i.m), respectively.

4. The connection interface (1) according to one of the claims 1 to 3, wherein the plurality of damping elements comprise a plurality of elastic elements integral to the frame (10), the plurality of elastic elements protruding from the second surface (10B) of the frame (10) in a direction parallel to the assembly direction (A).

5. The connection interface (1 ) according to any one of claims 1 to 4, further comprising a light guide (15) integrated into the frame (10), configured and arranged to guide a light beam between a first end (15in) arranged on an inner surface (10in) of the frame (10) and a second end (15out) arranged on an outer peripheral surface (10out) of the frame (10).

6. The connection interface (1) according to claim 5, wherein: the first end (15in) of the light guide (15) is configured to capture the light beam from a first light direction (L1) orthogonal to the second surface (10B) of the frame (10); the light guide (15) comprises a curved surface (15c) configured to deflect the light beam from the first light direction (L1) into a second light direction parallel to the first surface (10A) of the frame (10); the second end (15out) of the light guide (15) is configured to dissipate the light beam in the second light direction (L2).

7. The connection interface (1) according to claim 6, wherein the curved surface (15c) comprises a channel with a three-dimensional profile, the channel having a deltashaped cross-section in the direction of the first surface (10A).

8. The connection interface (1 ) according to claim 6 or 7, wherein upper and lower surfaces of the light guide (15) are provided with a structured pattern comprising concave and convex elements.

9. The connection interface (1) according to one of the claims 1 to 8, wherein the re- verse-locking mating elements (18i.n) are configured to engage with complementary reverse-locking mating elements (28-i-n) of the HVAC device block (20), the reverselocking mating elements (18i.n) each comprising: a deflection surface (186i.n) configured to deflect a flexible part (283i.n) of a complementary reverse-locking mating element (28i.n) upon the HVAC device block (20) being brought into contact with the connection interface (1) in the assembly direction (A); and a latching surface (188i.n) configured to retain a retainer part (286i.n) disposed at a distal end of the complementary reverse-locking mating element (28i.n) once the distal end of the complementary reverse-locking mating element (28i.n) passes a distal end of the deflection surface (186i.n).

10. The connection interface (1) according to claim 9, wherein the deflection surface (186i-n) of each reverse-locking mating element (18i.n) comprises a gap portion (1851 > n) for allowing penetration of needles of a removal tool to deflect the flexible parts (282i-n) of the complementary reverse-locking mating elements (28i.n).

11. The connection interface (1) according to one of the claims 1 to 10, the frame (10) comprising one or more alignment elements (17) arranged to align the HVAC device block (20) when brought into contact with the connection interface (1 ) in the assembly direction (A).

12. The connection interface (1) according to one of the claims 1 to 11 , wherein: the frame (10) is made of a transparent material, in particular a polycarbonate; andthe seal (16) including its plurality of protrusions (16i-m) is made of an elastic material, in particular a thermoplastic elastomer.

13. The connection interface (1) according to one of the claims 1 to 12, wherein the frame (10) comprises an extension surface (19) arranged outside the circumferential groove (14).

14. An HVAC device block (20) comprising: a housing (22); a printed circuit board (25) arranged within the housing (21) and accommodating an electronic circuit (23); a connection interface (1) according to one of the claims 1 to 13, joined with the housing (22) by welding a circumferential ridge (19), arranged on the second surface (10B) of the frame (10) opposite the first surface (10A), with a corresponding circumferential edge (29) on the housing (22), the damping elements being brought into contact with the printed circuit board (25) to thereby secure the printed circuit board (25).

15. The HVAC device block (20) according to claim 14, further comprising a plurality of complementary reverse-locking mating elements (28i.n) arranged on the housing (22).

16. The HVAC device block (20) according to claim 15, wherein the plurality of complementary reverse-locking mating elements (28-i-n) each comprise a flexible part (283i. n) and a retainer part (286i.n) disposed at a distal end of the complementary reverselocking mating element (28i.n).

17. The HVAC device block (20) according to one of the claims 14 to 16, the printed circuit board (25) further comprising a light source (27), the light source (27) being directed such as to emit light in the first light direction (L1) of the light guide (15) of the connection interface (1).

18. The HVAC device block (20) according to claim 17, wherein the printed circuit board (25) comprises openings to allow needles (50) of a removal tool to penetrate through the printed circuit board (25) for deflecting the flexible parts (282i.n) of the complementary reverse-locking mating elements (28i.n).

19. An HVAC field device (100) comprising a first HVAC device block (20i) and a second HVAC device block (2O2) according to one of the claims 14 to 18, the first HVAC device block (20i) being fixedly attached on top of the second HVAC device block (2O2), by engagement of the plurality of complementary reverse-locking mating elements (28i-n) arranged on the bottom of the first HVAC device block (20i) with the plurality of reverse-locking mating elements (18i.n) of the connection interface (1) of the second HVAC device block (2O2).

20. A method of manufacturing a connection interface (1) for fixedly receiving an HVAC device block (20) in an assembly direction (A), the method comprising: providing a frame (10) having: an opening (12); a circumferential groove (14) on a first surface (10A) of the frame (10) orthogonal to the assembly direction (A), the circumferential groove (14) surrounding the opening (12); a plurality of reverse-locking mating elements (18i.n) distributed around an outer circumference (13) of the opening (12); injection molding a seal (16) into the circumferential groove (14); and providing a plurality of damping elements arranged around an outer circumference (13) of the opening (12), the plurality of damping elements extending - in a direction parallel to the assembly direction (A) - beyond a second surface (10B) of the frame (10) opposite the first surface (A).

21. The method of manufacturing a connection interface (1) according to claim 20, further comprising the step of providing a plurality of through-channels (142i.m) connecting the circumferential groove (14) with the second surface (10B) of the frame (10), wherein the plurality of damping elements are provided by injection molding, into the plurality of through-channels (142i.m) of the circumferential groove (14), a plurality of protrusions (16i.m) as damping elements integral with the seal (16), such that the plurality of protrusions (16i-m) extend through the frame (10) beyond the second surface (10B) of the frame (10).

22. The method of manufacturing a connection interface (1) according to claim 20 or 21 , further comprising providing a plurality of elastic elements integral to the frame (10) as damping elements, the plurality of elastic elements protruding from the second surface (10B) of the frame (10) in a direction parallel to the assembly direction (A).

23. The method of manufacturing a connection interface (1) according to one of the claims 20 to 22, further comprising integrating a light guide (15) into the frame (10), configured and arranged to guide a light beam between a first end (15in) arranged on an inner surface (10in) of the frame (10) and a second end (15out) arranged on an outer peripheral surface (10out) of the frame (10).

24. The method of manufacturing a connection interface (1 ) according to claim 23, further comprising providing a curved surface (15c) within the light guide (15), the curved surface (15c) comprising a channel with a three-dimensional profile, the channel having a delta-shaped cross-section in the direction of the first surface (10A).

25. The method of manufacturing a connection interface (1) according to claim 23 or 24, further comprising providing upper and lower surfaces of the light guide (15) with a structured pattern comprising concave and convex elements.

26. The method of manufacturing a connection interface (1) according to one of the claims 20 to 25, wherein the reverse-locking mating elements (181-n) are configured to engage with complementary reverse-locking mating elements (281-n) of the HVAC device block (20), the reverse-locking mating elements (181-n) each comprising: a deflection surface (186i.n) configured to deflect a flexible part (283i.n) of a complementary reverse-locking mating element (28i.n) upon the HVAC device block (20) being brought into contact with the connection interface (1) in the assembly direction (A); and a latching surface (188i.n) configured to retain a retainer part (286i.n) disposed at a distal end of the complementary reverse-locking mating element (28i.n) once the distal end of the complementary reverse-locking mating element (28i.n) passes a distal end of the deflection surface (186i.n).

27. A method of manufacturing an HVAC device block (20), comprising manufacturing a connection interface (1) according to the method of one of the claims 20 to 26; providing: a housing (22); a printed circuit board (25) arranged within the housing (21) and accommodating an electronic circuit (23); and welding a circumferential ridge (19), arranged on the second surface (10B) of the frame (10) opposite the first surface (10A), with a corresponding circumferential edge (29) on the housing (22), the damping elements being brought into contact with the printed circuit board (25) to thereby secure the printed circuit board (25).

28. The method of manufacturing an HVAC device block (20) according to claim 27, further comprising providing a plurality of complementary reverse-locking mating elements (28i-n) arranged on the housing (22), the complementary reverse-locking mating elements (28i.n) each comprising: a flexible part (283i.n) configured to deflect upon being brought into contact, in the assembly direction (A), with the deflection surface (186i.n) of the connection interface (1); and a retainer part (286i.n) disposed at a distal end of the complementary reverse-locking mating element (28i.n) and configured to the engage with the latching surface (1881- n) of the reverse-locking mating elements (18i.n) once the distal end of the complementary reverse-locking mating element (28i.n) passes a distal end of the deflection surface (186i.n).

29. A method of manufacturing of an HVAC field device (100) comprising: manufacturing a first HVAC device block (20i) and a second HVAC device block (2O2) according to the method of claim 27 or 28, and bringing the first HVAC device block (20i) in contact with the second HVAC device block (2O2) in the assembly direction (A), thereby causing the plurality of complementary reverse-locking mating elements (28i.n) of the first HVAC device block (20i) to engage with the plurality of reverse-locking mating elements (18i.n) of the connection interface (1) of the second HVAC device block (2O2) to thereby attach the first HVAC device block (20i) on top of the second HVAC device block (2O2).

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