Temperature sensor array and method for producing temperature sensor array

Abstract

A temperature sensor array (1) is described. The temperature sensor array according to the invention comprises a heat sink (2) for absorbing heat, a holding clip (3) and a temperature sensor (4). In this case, the retaining clip (3) is fastened to the heat sink (2), and the temperature sensor (4) is fixed by means of the retaining clip (3).

Description

Technical Field

[0001] The present invention relates to a temperature sensor array and a method for manufacturing a temperature sensor array. Background Art

[0002] In power electronics, switching modules are used for motor control. High currents in the switching modules generate high power losses in the form of heat, which leads to power limitations. To improve the power utilization of the components used, component temperature monitoring is necessary. Only with this information can the power of the components be optimally utilized. This is often the case for thermally loaded components.

[0003] Typically, the temperature sensor is connected to the heat sink using a heat-conducting medium, such as a conductive adhesive. This is usually done directly with insulated components. For components that still need to be insulated, an insulating intermediate piece is required. This is often done using direct copper bonding technology, meaning that the component is insulated using a ceramic intermediate piece. The temperature sensor is also often directly integrated onto the circuit carrier used for the power switch.

[0004] When integrating temperature sensors into power switches, thermal side effects can falsify the measurement results, which then have to be recalculated, which has a negative impact on the accuracy of the result and means increased complexity.

[0005] Integrating the temperature sensor into the switching module results in an increase in component size and higher costs.

[0006] What is desired is a temperature sensor array that enables the measurement of the temperature of the heat sink to be achieved in a manner that is as easy to manufacture, cost-effective, and flexible as possible. Summary of the Invention

[0007] This object is achieved by the temperature sensor array according to the invention according to claim 1. This is achieved by a retaining clip fastened to the heat sink. The retaining clip is designed to accommodate the temperature sensors. Furthermore, the retaining clip is cost-effective and can be fastened to the heat sink in a manner that is consistent with production. The temperature sensors can be connected to or disconnected from the retaining clip at any time, which results in flexible manufacturability of the temperature sensor array. Furthermore, the retaining clip enables flexible positioning of the temperature sensors on the heat sink and a good thermal connection.

[0008] The temperature sensor is preferably electrically contactable and allows the temperature to be evaluated based on a change in the resistance of an electrical conductor in the temperature sensor or based on the thermoelectric effect.

[0009] The dependent claims reveal preferred developments of the invention.

[0010] The heat sink preferably has a solderable connection surface, wherein the retaining clip is soldered to the solderable connection surface. The solderable layer can be implemented, for example, as a copper cold gas coating. The soldered connection has high mechanical strength while also having good thermal conductivity. This method is particularly widespread and advantageous in the production of electronic products.

[0011] Other advantageous joining methods for the retaining clip on the heat sink include through-joining, stamping, riveting, screwing or gluing.

[0012] The heat sink is preferably a printed circuit board, cooling element, or electrical component. In particular, high currents often flow through electrical components such as those from power switches. These components, due to their internal resistance, act as heat sources and generate waste heat. This can be detrimental to the durability, efficiency, and effective power of the components, and therefore should be monitored using a temperature sensor array. Temperature monitoring is best performed using a heat sink that is directly thermally connected to the heat source. This is particularly true of the electrical component housing, printed circuit board, or cooling element.

[0013] The retaining clip is preferably a sheet-metal component. This can be easily and cost-effectively produced from a semi-finished sheet metal component using stamping and bending processes. Furthermore, the sheet-metal retaining clip can have high thermal conductivity, allowing the temperature sensor to measure the heat sink temperature as directly as possible. The elastic properties of the sheet-metal retaining clip allow for the manufacture of a retaining clip that securely secures the temperature sensor. Furthermore, the selection of the retaining clip material allows for adaptation to the preferred method for thermal connection to the heat sink.

[0014] As a further advantageous embodiment, the retaining clip can be realized as a cast component made of metal or plastic.

[0015] In a preferred embodiment, the retaining clip secures the temperature sensor in a force-locking manner. The force-locking connection can be achieved, for example, by clamping. The force-locking connection can be easily established and released by the joining force. Furthermore, the force-locking connection generally does not require additional joining elements. However, these additional joining elements represent a feasible option for establishing a reliable and durable connection.

[0016] The temperature sensor can preferably be fixed in a form-fitting manner by the retaining clip. A form-fitting connection is particularly reliable, but often requires additional engaging elements. These additional engaging elements can be designed to be releasable or non-releasable. An example of a form-fitting connection is a safety clip, which, after the temperature sensor has been inserted into the retaining clip, is connected to the retaining clip and now secures the temperature sensor and the retaining clip together in a form-fitting manner.

[0017] Furthermore, the temperature sensor is preferably fixed by the retaining clip not only in a form-fitting manner but also in a force-fitting manner. This results in a particularly reliable connection.

[0018] Furthermore, the retaining clip can preferably include a contact region disposed between the temperature sensor and the heat sink. This contact region allows for easy connection between the retaining clip and the heat sink. Furthermore, the contact region preferably has high thermal conductivity and thus provides a good thermal connection between the temperature sensor and the heat sink.

[0019] In a preferred embodiment, the temperature sensor can be electrically contacted with the heat sink via an electrical contact. The heat sink can be implemented, for example, as a printed circuit board having an electrical contact surface, with which the temperature sensor is in electrical contact. The temperature sensor is secured to this contact surface via a retaining clip. This contact surface allows the temperature sensor to directly contact the heat sink to detect the temperature. Consequently, subsequent electrical contacting of the temperature sensor, such as via a cable, is not required. Furthermore, the remaining parts of the temperature sensor should be insulated from the heat sink to prevent short circuits.

[0020] The present invention also relates to a method for manufacturing a temperature sensor array. The method comprises the steps of attaching a retaining clip to a heat sink, securing temperature sensors to the retaining clip, and electrically contacting the temperature sensors. These steps can be performed in any order. In particular, securing the temperature sensors to the retaining clip can be performed before or after attaching the retaining clip to the heat sink. Thus, the temperature sensors do not need to be directly secured to the heat sink, but can be flexibly secured to the heat sink via the retaining clip.

[0021] The retaining clip is preferably assembled in the same process step as the other electrical components. This reduces processing costs and time, as no additional process steps are required. This is not possible with temperature sensors according to the prior art, as these are typically fastened to the heat sink in an additional step using conductive adhesive.

[0022] Further advantageously, the retaining clip is placed on the heat sink in an automated assembly process. In the assembly process, the retaining clip is preferably assembled together with other electrical components. Subsequently, preferably not only the retaining clip but also the other electrical components are soldered.

[0023] In a preferred embodiment, the retaining clip and the temperature sensor are pre-assembled and attached to the heat sink. Thus, the retaining clip can be provided by a supplier, for example, pre-assembled with the temperature sensor. Subsequently, only the assembly consisting of the retaining clip and the temperature sensor needs to be fixed to the heat sink and electrically contacted, thus saving time and costs.

[0024] In another advantageous embodiment, the temperature sensor is subsequently fixed to a retaining clip connected to the heat sink. This allows different temperature sensors designed for different applications to be flexibly fastened to the same retaining clip. Furthermore, the temperature sensor can be installed at any later time and is not subject to process restrictions. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the accompanying drawings: Figure 1 shows a schematic diagram of a heat sink with a solderable connection surface according to a first embodiment, Figure 2 shows a schematic diagram of a temperature sensor array according to a first embodiment, Figure 3 shows a detailed schematic diagram of a temperature sensor array according to a first embodiment, and Figure 4 FIG. 4 shows a detailed schematic diagram of a temperature sensor array according to a second embodiment. DETAILED DESCRIPTION

[0026] Figures 1 to 3 A first embodiment of a temperature sensor array is shown. Here, Figure 1 The heat sink 2 is shown in the form of a plate-shaped cooling element 5. Solderable connection surfaces 21 are mounted on the cooling element 5 for surface-mount mounting (SMT) of the retaining clip 3 or the electrical component 6. The large solderable connection surfaces 21 are designed to accommodate a circuit breaker. A solder resist is preferably applied between the solderable connection surfaces 21.

[0027] Solder paste can be applied to the solderable connection surface by solder paste printing. The cooling element 5 is preferably flat and preferably has a high thermal conductivity. As an alternative, the retaining clip 3 can also be applied to a non-flat heat sink 2.

[0028] Figure 2 After the mounting of the applied retaining clip 3 and the electrical component 6, the Figure 1 The cooling element 5 is attached. The circuit breaker can be applied in a later process step. The retaining clip 3 can be applied quickly and cost-effectively using a common assembly process. The retaining clip 3 and the electrical component 6 rest on a solder deposit previously applied to the solderable connection surface by printing solder paste. The electrical component 6 and the retaining clip 3 can then be soldered together by melting the solder deposit in a soldering furnace.

[0029] It is also conceivable that the retaining clip 3 and / or the electrical component 6 are designed to be connected to the cooling element 5 by means of push-in connection (THT).

[0030] Figure 3A detailed view of a temperature sensor array 1 according to a first exemplary embodiment is shown. In this case, in a previous step, a retaining clamp 3 made of sheet metal is soldered to a solderable connection surface 21 , and subsequently the temperature sensor 4 is connected to the retaining clamp 3 .

[0031] Temperature sensor 4 has a first electrical contact 41, a second electrical contact 42, and a third electrical contact 43, which extend parallel to one another and to the surface of heat sink 2 from a housing 44 of temperature sensor 4. Housing 44 is cuboid and has chamfers at both upper longitudinal edges. Temperature sensor 4 is located on contact area 31 of retaining clip 3.

[0032] Furthermore, the housing 44 of the temperature sensor can be a standardized housing, for example a transistor-outlet (TO) housing.

[0033] In the first embodiment, the contact region 31 has two outer tabs 32, which are arranged parallel to each other and perpendicular to the electrical contacts 41, 42, 43 and are centrally connected. A tab branches off from the central connection, which is bent and forms a lateral stop 33 for the temperature sensor 4. The flat outer tab 32 transitions to an upwardly curved region 34 on the side opposite the stop 33. The curvature diameter of the curved region 34 is slightly greater than the height of the temperature sensor 4. The curved region 34 forms a semicircular shape. Connecting to the curved region 34 is a connecting tab 35, which is slightly bent downward toward the temperature sensor 4. The two connecting tabs 35 are connected to a fixing region 36, which is arranged perpendicular to the connecting tabs. The fixing region is placed flat on the temperature sensor 4 and fixes it.

[0034] The long end of the fixing region 36 is protruded by an upwardly bent surface 37. This upwardly bent surface facilitates the side engagement of the temperature sensor 4 into the retaining clip 3. An upwardly bent connecting piece 38 is attached to the long edge of the fixing region extending from the arcuately bent region 34. The upwardly bent connecting piece 38 facilitates the upward bending of the fixing region 36 for installation or removal of the temperature sensor 4 in the retaining clip 3.

[0035] exist Figure 3 In the embodiment shown in FIG. 1 , the retaining clip 3 is elastically bent upward to secure the temperature sensor 4. Through this elastic deformation, the retaining clip 3 exerts a retaining force on the temperature sensor 4 via the securing region 36 and secures it in the retaining clip 3 in a force-locking manner. Lateral stops 33 secure the temperature sensor 4 laterally in a form-fitting manner. Without the temperature sensor 4 installed, the arched region 34 is bent slightly further downward, and the securing region 36 is thus brought closer to the contact region 31.

[0036] As a second method of the first embodiment, the temperature sensor 4 can be connected to the holding clip 3 before being fixed to the heat sink 2 .

[0037] The temperature sensor array 1 having the features of the first exemplary embodiment and the steps for producing the temperature sensor array 1 therefore enable a process-friendly, cost-effective and flexible measurement of the temperature on the heat sink.

[0038] Figure 4 A detailed view of a temperature sensor 4 in a retaining clip 3 according to a second embodiment is shown. In this second embodiment, the retaining clip 3, made of sheet metal, is constructed in two parts. The lower part 8 has a U-shaped cross-section with a flat contact area 31 and two inner side walls 81 bent upward by 90°. The inner side walls 81 have a centrally punched rectangular window 82. The inner spacing between the parallel inner side walls 81 corresponds to the width of the temperature sensor 4.

[0039] The upper component 7 also has a U-shaped cross-section, with two outer sidewalls 71 bent downward at 90°. The outer sidewalls are bent outward at their outer ends to facilitate better connection between the upper component 7 and the lower component 8. The inner spacing between the outer sidewalls 71 corresponds to the outer spacing of the inner sidewalls 81. The outer sidewalls 71 also have inwardly pressed recesses 72, which are designed to fit into rectangular windows 82 in the inner sidewalls 81. By fitting the recesses 72 into the rectangular windows 82, the upper component 7 is securely positioned on the lower component 8 and can only be removed by bending the outer sidewalls 71. The upper side 73 of the upper component 7, located between the two outer sidewalls 71, has an arcuate, downwardly curved, elastic cross-section. In the engaged state, this cross-section contacts the temperature sensor 4 and applies a retaining force to it, thereby connecting the temperature sensor 4 to the retaining clip 3 in both a force-locking and a form-locking manner.

Claims

1. A temperature sensor array (1), comprising a heat sink (2) for absorbing heat, a retaining clip (3) and a temperature sensor (4), • in, The retaining clip (3) is fastened to the heat sink (2), and • wherein the temperature sensor (4) is fixed by means of the retaining clamp (3).

2. The temperature sensor array (1) according to claim 1, wherein: The heat sink (2) has a solderable connection surface (21), and the retaining clip (3) is soldered to the solderable connection surface (21) of the heat sink (2).

3. The temperature sensor array (1) according to any one of the preceding claims, wherein The heat sink (2) is a printed circuit board or a cooling element (5) or an electrical component (6), in particular a circuit breaker.

4. The temperature sensor array (1) according to any one of the preceding claims, wherein The retaining clip (3) is a plate-shaped component.

5. The temperature sensor array (1) according to any one of the preceding claims, wherein The retaining clamp (3) fixes the temperature sensor (4) in a force-locking manner.

6. The temperature sensor array (1) according to any one of the preceding claims, wherein The retaining clip (3) fixes the temperature sensor (4) in a form-fitting manner.

7. The temperature sensor array (1) according to any one of the preceding claims, wherein The retaining clip (3) comprises a contact area (31) arranged between the temperature sensor (4) and the heat sink (2).

8. The temperature sensor array (1) according to any one of the preceding claims, wherein The temperature sensor (4) can be electrically contacted via the heat sink (2).

9. A method for manufacturing a temperature sensor array (1) on a heat sink (2), the method comprising the following steps: • Engage the retaining clip (3) on the heat sink (2), • Fix the temperature sensor (4) to the retaining clip (3), and • Electrical contact to the temperature sensor (4).

10. The method according to claim 9, wherein: The retaining clip (3) is assembled in the same process step as the other electrical components.

11. The method according to claim 9 or 10, wherein: The retaining clip (3) is fastened to the heat sink (2) in an automated assembly process.

12. The method according to claims 9 to 11, wherein: The retaining clip (3) and the temperature sensor (4) are joined to the heat sink (2) in a pre-assembled manner.

13. The method according to claims 9 to 11, wherein: After the retaining clip (3) has been joined to the heat sink (2), the temperature sensor (4) is fixed to the retaining clip (3).

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