Method for producing temperature sensors and temperature sensor produced thereby
Patent Information
- Application Number
- PCT/EP2026/058363
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-25
- Filing Date
- 2026-03-24
- Publication Date
- 2026-10-01
Smart Images
Figure EP2026058363_01102026_PF_FP_ABST
Abstract
Description
[0001] Method for manufacturing temperature sensors and temperature sensor manufactured using this method
[0002] Description
[0003] Reference to related applications
[0004] The present application refers to and claims priority of German patent application 102025001 020.6, filed on March 25, 2025, the disclosure content of which is hereby expressly made the subject matter of the present application in its entirety.
[0005] Field of invention
[0006] The present invention relates to a method for manufacturing temperature sensors and to a temperature sensor manufactured according to the method according to the invention.
[0007] State of the art
[0008] Methods for manufacturing temperature sensors, especially high-pressure temperature sensors, are often inefficient in production and processing quality when dealing with large quantities, and the temperature sensors produced using these methods often lack sufficient mechanical and electrical properties.
[0009] Known temperature sensors, such as high-pressure temperature sensors arranged in a metal tube, lack sufficient fracture resistance due to their design and the components used. Furthermore, automated processing is at least difficult, as the connecting pins, usually designed as contact wires, can bend during the manufacturing process. Summary of the invention
[0010] The invention is therefore based on the objective of providing a method for manufacturing temperature sensors by means of which these can be produced in good quality in large quantities and in which the temperature sensors produced thereby have good mechanical and electrical properties.
[0011] Description of the invention
[0012] This problem is solved by a method according to the features of claim 1. This method is for manufacturing temperature sensors, in particular high-pressure temperature sensors, which is preferably carried out on a machine for producing at least two separate metallic die-cut grids, optionally on a machine for electroplating the die-cut grids, on a machine for manufacturing injection-molded plastic parts, and on a machine for placing an SMD chip on the die-cut grids and soldering the SMD chip to the die-cut grids. In principle, an integrated solution is also possible in which the process steps are combined on one or more machines.
[0013] The process comprises the following steps: producing at least two metallic carrier strips, at least partially adapted in their shapes to one another, each within a die-cutting grid, the die-cutting grids being punched in separate die-cutting paths. Optionally, it includes electroplating at least the carrier strips, positioning the carrier strips parallel to one another in an injection mold of a machine for producing plastic injection-molded parts, and overmolding the carrier strips with a plastic to produce at least one injection-molded part. At least the connecting pins of the carrier strips remain exposed at one end, and contact surfaces of the carrier strips remain at least partially exposed at the other end, with the carrier strips being fixed in their relative positions.
[0014] Furthermore, the process includes separating the at least one injection-molded part with the carrier strips from the die-cut grids, placing an SMD chip on the contact surfaces, and soldering the SMD chip to the contact surfaces. Advantageously, a temperature sensor can be produced as an assembly with good fracture resistance in this way. The sandwich structure created during the overmolding of the carrier strips results in particularly good stability and flexural rigidity, which are especially advantageous for high-pressure temperature sensors.
[0015] This makes the process efficient in production and ensures the processing quality of the manufactured temperature sensors for processing large quantities.
[0016] The problem is also solved by a temperature sensor, in particular a high-pressure temperature sensor, according to claim 14, which is manufactured according to the inventive method. The temperature sensor has at least two metallic carrier strips arranged parallel to each other in a planar fashion, their shapes at least partially adapted to one another, and an injection-molded plastic part surrounding them. The carrier strips each have connection pins at one end of the carrier strips that remain free of the plastic and contact surfaces at the other end of the carrier strips that remain at least partially free of the plastic.The injection-molded part exhibits a predetermined tensile strength and flexural stiffness, and the connecting pins are mechanically stable within the part. The injection-molded part also possesses a predetermined volume resistivity, surface resistivity, comparative tracking index, and dielectric strength. Consequently, the temperature sensors produced using this method exhibit advantageously good mechanical and electrical properties.
[0017] Advantageous further developments are the subject of the dependent patent claims.
[0018] In a preferred embodiment of the method, which advantageously optimizes the space requirements of the temperature sensor, the ends of the connecting pins of both carrier strips can be directly opposite each other in the die-cut grids. One of the carrier strips can be shorter than the other, and the ends of the carrier strips can be angled at approximately 90° towards the other carrier strip with their contact surfaces. Furthermore, the contact surface of the shorter carrier strip can be positioned in front of the contact surface of the longer carrier strip in the longitudinal direction of the temperature sensor. A section of the longer carrier strip near the contact surface of the shorter carrier strip can be shifted parallel to itself during the die-cutting process, so that the contact surface of the shorter carrier strip can be positioned above the longer carrier strip and the contact surfaces can be opposite each other.
[0019] In a preferred embodiment of the method, which advantageously improves the stability of the carrier strips during injection molding and thus the electrical properties of the temperature sensor, the carrier strips can be held at a predetermined distance from each other in the injection mold during overmolding by positioning pins. The contact surface of the longer carrier strip can also be held by a positioning punch, which may have a recess for receiving at least part of the section.
[0020] In a preferred embodiment of the method, which advantageously improves the efficiency of the process and the electrical properties of the temperature sensor, the carrier strips can be provided with predetermined breaking points during the stamping process, allowing them to be separated from the rest of the stamped grid after overmolding. These predetermined breaking points can be located, at least partially, at recessed areas on the circumference of the at least one injection-molded part and at predetermined intervals from one another. This not only advantageously facilitates the simple separation of the carrier strips from the stamped grid, but also ensures that air gaps and creepage distances can be reliably and permanently maintained.
[0021] In a preferred embodiment of the method which advantageously improves the efficiency of the process, the assembly and soldering can be performed as with a printed circuit board.
[0022] In a preferred embodiment of the method, which advantageously improves efficiency, the at least one injection-molded part, after being cut out of the die grids, can be placed into at least one recess of a workpiece carrier of the machine for loading. The injection-molded part can be fixed in the recess by means of a slide, which can be arranged to be parallel-slidably mounted on the workpiece carrier, which can have at least one comb-like leg formed integrally with the slide on at least one side, and which can be angled at approximately 90° at an end remote from the slide.
[0023] In a preferred embodiment of the method which advantageously improves the efficiency of the process, an electrical and / or optical test can be carried out after soldering in the workpiece carrier.
[0024] In a preferred embodiment of the method which advantageously improves the weight, strength, corrosion resistance, durability and temperature resistance, the workpiece carrier can be made of metal, preferably titanium.
[0025] In a preferred embodiment of the method which advantageously improves the efficiency of the method, the workpiece carrier can have several parallel recesses on both sides of the slide and the slide can have integrally formed comb-like legs on both sides which can be angled at approximately 90° at their ends.
[0026] In a preferred embodiment of the method which advantageously improves the safety of the method, the at least one comb-like leg can be integrally formed with the slide at least on one side, be angled at its end by approximately 90° and have a maximally enlarged surface which, in the unmoved state of the slide, enables the insertion of the at least one injection-molded part into the at least one recess.
[0027] In a preferred embodiment of the method which advantageously improves the safety of the method, a contact surface of a dispenser of a machine for loading and soldering on the workpiece carrier can have a predetermined minimum area.
[0028] In a preferred embodiment of the method which advantageously improves the efficiency and safety of the method, the workpiece carrier can have an insulating plate arranged below the connection pins at the level of these pins, which can enable resistance measurements on the connection pins and the at least one injection-molded part.
[0029] In a preferred embodiment of the temperature sensor which advantageously improves the safety of the temperature sensor, the carrier strips surrounded by the injection-molded part can have predetermined air gaps and creepage gaps in the injection-molded part.
[0030] The features listed individually in the patent claims can be combined in a technologically meaningful way and can be supplemented by explanatory facts from the description and by details from the figures, showing further embodiment variants of the invention.
[0031] Brief description of the characters
[0032] The invention will now be explained in more detail using an exemplary embodiment. Figure 1 shows two die-cut grids with support strips and an injection-molded part.
[0033] Fig. 2 shows different views of carrier strips positioned relative to each other, Fig. 3 shows a section of the carrier strips from Fig. 2 with contact surfaces,
[0034] Fig. 4 shows a section of the carrier strips from Fig. 2 with contact surfaces and soldered SMD chip,
[0035] Fig. 5 shows a sectional view through a temperature sensor during the injection molding process.
[0036] Fig. 6 shows a top view of the finished temperature sensor from Fig. 5.
[0037] Fig. 7 shows a sectional view through the temperature sensor from Fig. 5.
[0038] Fig. 8 shows a perspective view of a finished temperature sensor.
[0039] Fig. 9 shows a workpiece carrier,
[0040] Fig. 10 shows a section of the workpiece carrier from Fig. 9 with the slide open, Fig. 11 shows a section of the workpiece carrier from Fig. 9 with the slide closed.
[0041] Slide valve. Detailed description of preferred embodiments
[0042] The invention will now be explained in more detail by way of example with reference to the accompanying drawings. However, the exemplary embodiments are merely examples and are not intended to limit the inventive concept to a specific arrangement. Before the invention is described in detail, it should be noted that it is not limited to the respective components of the device or the respective process steps, as these components and processes can vary. The terms used here are intended solely to describe particular embodiments and are not used restrictively. Furthermore, where the singular or indefinite articles are used in the description or in the claims, this also refers to the plural of these elements, unless the overall context clearly indicates otherwise.
[0043] The method for manufacturing temperature sensors 1, preferably high-pressure temperature sensors, is preferably carried out with the following machines: a machine for manufacturing at least two separate metallic die-cut grids 10, 11; optionally a machine for electroplating the die-cut grids 10, 11; a machine for manufacturing plastic injection-molded parts; and a machine for mounting an SMD chip 30 for the temperature sensor on the die-cut grids 10, 11 and for soldering the SMD chip 30 to the die-cut grids 10, 11. Of these machines, only the injection mold 35 of the machine for manufacturing plastic injection-molded parts is shown in Fig. 5.
[0044] The method comprises producing at least two metallic carrier strips 20, 21, their shapes at least partially adapted to one another, each within one of the die-cutting grids 10, 11, wherein the die-cutting grids 10, 11 are punched in separate die-cutting paths. The die-cut carrier strips 20, 21, which are used in place of the known contact wires, are integrally formed with connecting pins 22 at one end of the carrier strips 20, 21 and contact surfaces 23 at another end of the carrier strips 20, 21.
[0045] Preferably, the contact surfaces 23 for mounting SMD components are already integrated into the die-cut grid 10, 11. Furthermore, the die-cut grid 10, 11, and thus also the carrier strip 20, 21, can preferably be equipped with stable connection pins 22 to enable subsequent automated positioning in holes of a circuit board. The connection pins 22 can be die-cut in combination with the die-cut grid 10, 11, resulting in a rigid contour. Overmolding the die-cut grid then advantageously ensures precise and stable positioning of the connection pins 22. This approach enables automated further processing.
[0046] Optionally, the process includes electroplating at least the carrier strips 20, 21 on a suitable machine.
[0047] The carrier strips 20, 21 are positioned parallel to each other in an injection mold 35 of a machine for producing plastic injection-molded parts. In this machine, the carrier strips 20, 21 are overmolded with a plastic to produce at least one injection-molded part 40. At least the connecting pins 22 at one end of each carrier strip 20, 21 remain exposed, and the contact surfaces 23 at the other end of each carrier strip 20, 21 remain at least partially exposed, with the carrier strips 20, 21 preferably fixed in their relative position during overmolding.
[0048] The process further comprises separating the at least one injection-molded part 40 with the carrier strips 20, 21 from the die-cut grids 10, 11, placing an SMD chip 30 on the contact surfaces 23, and soldering the SMD chip 30 to the contact surfaces 23. The individual components of the temperature sensor 1 during its manufacture are shown in Fig. 1. The process is efficient in terms of production and the processing quality of the temperature sensors 1 produced by it is designed for large quantities.
[0049] The ends of the connecting pins 22 of both carrier strips 20, 21 can be directly opposite each other in the die-cutting grids 10, 11. Preferably, one of the carrier strips 21 can be shorter than the other carrier strip 20, and the ends of the carrier strips 20, 21 can be angled approximately 90° towards the other carrier strip 20, 21 with their contact surfaces 23. Preferably, the contact surface 23 of the shorter carrier strip 21 can be arranged in the longitudinal direction of the temperature sensor in front of the contact surface 23 of the longer carrier strip 20. In addition, a section 24 of the longer carrier strip 20 near the contact surface 23 of the shorter carrier strip 21 can be displaced parallel to each other during the die-cutting process, so that the contact surface 23 of the shorter carrier strip 21 can be arranged above the longer carrier strip 20 and the contact surfaces 23 can be opposite each other.Advantageously, this allows for a compact design of the temperature sensor 1, as shown in Figs. 1 to 4.
[0050] The carrier strips 20, 21 can be held at a predetermined distance from each other and in position in the injection mold 35 during the overmolding of positioning pins 50 according to Fig. 5. This ensures, among other things, that the contact surfaces 23 are flat relative to each other.
[0051] Furthermore, the contact surface 23 of the longer carrier strip 20 can preferably be held by a positioning punch 51, which may have a recess to receive at least part of the section 24. This design feature prevents the contact surface 23 from slipping outwards during overmolding. Otherwise, the contact surface 23 could slip laterally between the positioning pins, which could subsequently lead to contact between the contact surface 23 and the outer contour, potentially resulting in a failure to maintain the required clearance and creepage distances. The stability of the carrier strips 20, 21 during injection molding, and thus the electrical properties of the temperature sensor 1, in particular the clearance and creepage distances in the injection-molded part 40, can be reliably improved by using the positioning punch.
[0052] The carrier strips 20, 21 can be provided with predetermined breaking points 25 during the stamping process, as shown in Figures 1 to 4 and 8, at which they can be separated from the rest of the stamped grid 10, 11 after overmolding. The predetermined breaking points 25 can be arranged at least partially at recessed areas 41 on the circumference of the at least one injection-molded part 40 and at predetermined intervals from each other, as shown in Figures 1 to 4 and 8.
[0053] Figures 6 and 8 show that the injection-molded part 40 can be easily separated from the remaining die-cut grids 10 and 11. At the same time, air and creepage distances can be reliably maintained. The SMD chip 30 can be mounted and soldered in the same way as a printed circuit board. This allows existing machines and processes to be used. The SMD chip 30 is shown in Figures 4, 6, 7, and 8.
[0054] The steps of the process can be performed manually and / or automatically. This allows the most appropriate approach to be selected in each case.
[0055] The at least one injection-molded part 40, after being cut out of the dies 10, 11, can be inserted into at least one recess 61 of a workpiece carrier 60 of a machine for loading. The injection-molded part 40 can be inserted by means of a slide 62, which can be arranged to be parallel-displaceable on the workpiece carrier 60, which can have at least one comb-like leg 63 formed integrally with the slide 62 on at least one side, and which extends approximately 1 mm at an end away from the slide 62.
[0056] The workpiece carrier 60 can be angled at 90° and is fixed in the recess 61 by sliding the slide 62 off the leg 63. Fig. 9 shows an overview of the workpiece carrier 60, and Figs. 10 and 11 each show a detail view. In Fig. 10, the slide 62 is shown in its unmoved position, in which the injection-molded part 40 can be inserted into the recess 61 of the workpiece carrier 60, and in Fig. 11, it is shown in the moved position, in which the injection-molded part 40 is fixed in the workpiece carrier 60. This allows several injection-molded parts 40 to be efficiently populated and soldered with the SMD chip 30, especially when producing large quantities.
[0057] After the injection-molded parts 40 are inserted, they are fixed in place by the slide 62 during the subsequent process. There is no lifting during the dispensing of the solder paste.
[0058] After soldering in the workpiece carrier 60, an electrical and / or optical test can be performed. This advantageously allows the temperature sensor 1 to be manufactured and tested within the same production process.
[0059] The workpiece carrier 60 can be made of metal, preferably titanium. This advantageously improves the weight, strength, corrosion resistance, durability, and temperature resistance of the workpiece carrier 60. The workpiece carrier 60 can have several parallel recesses 61 on both sides of the slide 62, and the slide 62 can have integrally formed comb-like legs 63 on both sides, which can be angled at approximately 90° at their ends. This advantageously further improves the productivity of the process.
[0060] The at least one comb-like leg 63 can be integrally formed with the slide 62 on at least one side, be angled at approximately 90° at its end, and have a maximally enlarged surface area which, in the undisplaced state of the slide 62, allows the insertion of the at least one injection-molded part 40 into the at least one recess 61. The increased surface area advantageously reduces the temperature of the injection-molded part 40 and the SMD chip 30 during the soldering process.
[0061] The contact surface of a dispenser on a machine for placement and soldering on the workpiece carrier 60 can have a predetermined minimum area. This measure can also advantageously reduce the temperature of the injection-molded part 40 and the SMD chip 30 during the soldering process.
[0062] The workpiece carrier 60 can preferably have an insulating plate 64 arranged below the connection pins 22 at the level of these pins, which enables resistance measurements at the connection pins 22 and at least one injection-molded part 40. Advantageously, this allows for short-circuit-free testing of the finished temperature sensor 1.
[0063] The temperature sensor 1, preferably a high-pressure temperature sensor, produced by the method described above, comprises at least two parallel, horizontally arranged metallic carrier strips 20, 21, whose shapes are at least partially adapted to one another, and an injection-molded plastic part 40 surrounding them. The carrier strips 21, 21 each have connection pins 22 at one end that remain free of the plastic and contact surfaces 23 at the other end of the carrier strips 21, 21 that remain at least partially free of the plastic. The injection-molded part 40 has a predetermined tensile strength and flexural stiffness, and the connection pins 22 are mechanically stable within the injection-molded part 40.The injection-molded part 40 exhibits a predetermined electrical volume resistance, electrical surface resistance, comparative electrical tracking index, and a predetermined electrical dielectric strength. Therefore, the temperature sensors 1 produced by this method possess good mechanical and electrical properties.
[0064] The carrier strips 20, 21 surrounded by the injection-molded part 40 can have predetermined air gaps and creepage distances within the injection-molded part 40. This can advantageously improve the electrical properties of the temperature sensor 1.
[0065] It goes without saying that this description may be subject to various modifications, changes, and adaptations, which are equivalent to the attached claims. Reference numeral list
[0066] 1 temperature sensor,
[0067] 10, 11 punched grids,
[0068] 20, 21 carrier strips,
[0069] 22 connection pins,
[0070] 23 Contact area,
[0071] 24 parallel-displaced section of the carrier strip, 25 predetermined breaking point,
[0072] 30 SMD chips,
[0073] 35 injection molds,
[0074] 40 injection-molded parts,
[0075] 41 recessed areas around the circumference of the injection-molded part,
[0076] 50 positioning pins,
[0077] 51 positioning stamps,
[0078] 60 workpiece carriers,
[0079] 61 Recess of the workpiece carrier,
[0080] 62 slides of the workpiece carrier,
[0081] 63 Comb-like leg formed integrally with the slide, 64 Insulation plate.
Claims
Patent claims 1. Method for manufacturing temperature sensors (1), in particular high-pressure temperature sensors, comprising the steps: - Production of at least two metallic carrier strips (20, 21) whose shapes are at least partially adapted to one another in a die-cutting grid (10, 11), wherein the die-cutting grids (10, 11) are punched in separate die-cutting paths, - optional electroplating of at least the carrier strips (20, 21 ), - Positioning the carrier strips (20, 21) parallel to each other in an injection mold (35), - Overmolding the carrier strips (20, 21) in the injection mold (35) with a plastic to produce at least one injection-molded part (40), wherein at least connecting pins (22) of the carrier strips (20, 21) remain free at one end of the carrier strips (20, 21) and contact surfaces (23) of the carrier strips (20, 21) remain at least partially free at the other end of the carrier strips (20, 21) and wherein the carrier strips (20, 21) are fixed in their position relative to each other, - Cutting out the at least one injection-molded part (40) with the carrier strips (20, 21) from the die-cut grids (10, 11), - Mounting an SMD chip (30) on the contact pads (23), - Soldering the SMD chip (30) to the contact pads (23).
2. Method according to claim 1, characterized in that the ends of the connecting pins (22) of both carrier strips (20, 21) are arranged directly opposite each other in the punch grids (10, 11).
3. Method according to claim 1 or 2, characterized in that one of the carrier strips (21) is shorter than the other carrier strip (20), the ends of the carrier strips (20, 21) with the contact surfaces (23) are each angled by approximately 90° towards the other carrier strip (20, 21), and that when positioning the carrier strips (20, 21) in the injection molding tool (35), the contact surface (23) of the shorter carrier strip (21) is arranged in front of the contact surface (23) of the longer carrier strip (20).
4. Method according to claim 3, characterized in that a section (24) of the longer carrier strip (20) is shifted parallel to itself in the vicinity of the contact surface (23) of the shorter carrier strip (21) during the punching process, so that the contact surface (23) of the shorter carrier strip (21) is arranged over the longer carrier strip and the contact surfaces (23) are opposite each other.
5. Method according to claim 3 or 4, characterized in that the carrier strips (20, 21) in the injection molding tool (35) are held at a predetermined distance from each other during the overmolding of positioning pins (50) and wherein the contact surface (23) of the longer carrier strip (20) is held by a positioning punch (51) which has a recess for receiving at least a part of the part (24).
6. Method according to one of the preceding claims, characterized in that the carrier strips (20, 21) are provided with predetermined breaking points (25) during the stamping process, at which they are separated from the rest of the stamped grid (10, 11) after overmolding, and wherein the predetermined breaking points (25) are arranged at least partially at preferably recessed locations (41) of a circumference of the at least one injection molded part (40) and at predetermined distances from each other.
7. Method according to one of the preceding claims, characterized in that the assembly and soldering is carried out as with a printed circuit board.
8. Method according to one of the preceding claims, characterized in that the at least one injection-molded part (40) is inserted into at least one recess (61) of a workpiece carrier (60) after being cut out from the die grids (10, 11) and is fixed in the workpiece carrier (60) by means of a slide (62) which is arranged to be parallel-displaceable on the workpiece carrier (60) and which has at least one comb-like leg (63) formed integrally with the slide (62) on at least one side and which is angled at approximately 90° at an end away from the slide (62) by sliding the leg (63) in the recess (61).
9. Method according to claim 8, characterized in that the workpiece carrier (60) is made of metal, preferably titanium.
10. A method according to claim 8 or 9, characterized in that the workpiece carrier (60) has several parallel recesses (61) on both sides of the slide (62) and the slide (62) has comb-like legs (63) integrally formed on both sides, which are angled at their ends by approximately 90°.
11. A method according to any one of claims 8 to 10, characterized in that the at least one comb-like leg (63) integrally formed with the slide (62) on at least one side is angled at its end by approximately 90° and has a maximally enlarged surface area which, in the undisplaced state of the slide (62), enables the insertion of the at least one injection-molded part (40) into the at least one recess (61).
12. Method according to one of claims 8 to 11, characterized in that a support surface configured for a support of a dispenser of a machine for loading and soldering has a predetermined minimum area on the workpiece carrier (60).
13. Method according to one of claims 8 to 12, characterized in that the workpiece carrier (60) has an insulating plate (64) arranged below the connection pins (22) at the level of these, which enables resistance measurements at the connection pins (22) and the at least one injection molded part (40).
14. Temperature sensor (1), in particular a high-pressure temperature sensor, manufactured by a method according to one of claims 1 to 13, comprising at least two metallic carrier strips (20, 21) arranged parallel to one another in their shapes at least partially adapted to one another and an injection-molded part (40) made of plastic surrounding them, wherein the carrier strips (21, 21) each have connection pins (22) at one end of the carrier strips (21, 21) which remain free of the plastic and contact surfaces (23) at one other end of the carrier strips (21, 21) which remain free of the plastic, wherein the injection-molded part (40) has a predetermined tensile strength and flexural stiffness and the connection pins (22) are mechanically stable in the injection-molded part (40) and wherein the injection-molded part (40) each has a predetermined electrical volume resistance, electrical surface resistance,has a comparative electrical tracking index and a predetermined electrical dielectric strength.
15. Temperature sensor according to claim 14, wherein the carrier strips (20, 21) surrounded by the injection-molded part (40) have predetermined air gaps and creepage gaps in the injection-molded part (40).