Sensor and method for producing a sensor

Abstract

A sensor (1) comprises a measuring element (2), at least one connection cable (3) for contacting the measuring element (2), a first potting (4), and a second potting (5). The connection cable (3) is provided at a first end (11) of the sensor (1) and is in direct contact with the first potting (4), and the measuring element (2) is provided at a second end (12) of the sensor (1), is at least partly surrounded by the second potting (5), and is in direct contact with the second potting (5). In a transition region (13) between the first end (11) and the second end (12), the first potting (4) is in direct contact with the second potting (5). The sensor (1) is designed, for example, to detect the temperature of a motor, an electric motor or a component of an electric motor vehicle. The invention also relates to a method for producing a sensor.

Description

[0001] Description

[0002] Sensor and method for manufacturing a sensor

[0003] The invention relates to a sensor and a method for manufacturing a sensor. The sensor is specifically designed for temperature detection.

[0004] Temperature sensors are used, for example, to measure the temperature of objects or surfaces. Such objects can be, for example, current-carrying conductors, heat sinks, or fluid-carrying pipes. It is desirable that the temperature measurement is fast and that the measurement result corresponds to the object's temperature in thermal equilibrium. That is, response times for the temperature measurement should be, for example, less than 4 seconds, and the measurement result is preferably free of offset.

[0005] Furthermore, in many applications, corresponding sensors must exhibit a minimum insulation resistance. For example, the sensors should withstand operating voltages of up to 1000 V and test voltages of up to 5000 V. In addition, operating temperatures of up to 220 °C or higher may occur in some applications. This can limit the choice of materials, especially for the sensor housing.

[0006] Furthermore, small installation spaces often need to be realized, making miniaturization of the sensor desirable. At the same time, the sensor geometry is typically at least partially predetermined. For example, the insulation thickness and conductor diameter of connecting cables are often dictated by application-specific requirements, system-specific connector standards, and the required tensile and flexural strength of the cables.

[0007] To meet these requirements, temperature sensors often have a rectangular housing containing a measuring element and connected to supply cables. Such or comparable sensors, as well as methods for manufacturing corresponding sensors, are known, for example, from the publications JP 6674070 Bl, EP 4165381 Bl, JP 7058377 Bl, DE 102020107007 Al, JP 5574117 B2, WO 2015 / 132832 Al and JP 1729419 S.

[0008] One task to be solved is to specify an improved sensor for temperature measurement and a method for its manufacture.

[0009] These problems are solved by devices having the features of claims 1 and 17, respectively. Further embodiments and advantageous developments are the subject of the respective dependent claims.

[0010] A sensor is proposed comprising a sensing element, at least one connecting cable for contacting the sensing element, a first potting compound, and a second potting compound. The connecting cable is located at a first end of the sensor and is in direct contact with the first potting compound. The sensing element is located at a second end of the sensor, at least partially surrounded by the second potting compound, and is in direct contact with the second potting compound. In a transition region between the first and second ends, the first potting compound is in direct contact with the second potting compound.

[0011] The connecting cable allows the measuring element, and thus the sensor, to be electrically connected externally. Specifically, the sensor includes two connecting cables, which allow it to be integrated into an electrical circuit or similar device. When the term "connecting cable" is used here and in the following, it specifically refers to two connecting cables, unless otherwise stated.

[0012] In particular, the first potting compound at least partially surrounds the connecting cable. The first potting compound is, for example, a potting compound for the connecting cables. In other words, the connecting cable is potted by the first potting compound.

[0013] For example, at the first end the connecting cables are covered by the first potting compound.

[0014] The second potting compound preferably completely surrounds the measuring element. In particular, the measuring element is surrounded on all sides by the second potting compound and is in direct contact with it. The measuring element is specifically encapsulated by the second potting compound. The measuring element is specifically inaccessible from any area outside the sensor.

[0015] The first end can be opposite the second end. For example, the sensor is rod-shaped or approximately rod-shaped. A principal direction of extension of the sensor is, in particular, a direction extending from the first end to the second end. Preferably, the principal direction of extension is straight. The sensor described here is based, among other things, on the following technical considerations. During the manufacturing of the sensor, the pottings can preferably be produced independently of each other and sequentially. For example, the first potting is produced first using a first mold. Subsequently, the second potting is produced using a second mold. This creates, in particular, the transition area where the first and second pottings directly adjoin each other.

[0016] During manufacturing, the first casting can be used for precise positioning in the second mold. This means the sensor can be manufactured with exceptional accuracy.

[0017] This contrasts with manufacturing processes where a sensor encapsulation is produced using a heat-shrink tubing process or in a single casting step. These two methods are particularly disadvantageous with regard to tensile strength. Furthermore, sensors manufactured using these methods typically have larger dimensions, and especially with the heat-shrink tubing process, the shape is difficult to control.

[0018] Furthermore, the parameters of the second potting can be selected independently of those of the first. For example, the second potting can have a different geometric shape and / or use different materials than the first. The sensor's other end, which is specifically a measuring area of ​​the probe, can be particularly well adapted to a specific measurement environment or application. The sensor described here, for example, is a temperature sensor for detecting the temperature of a measurement environment. The measurement environment can be, for example, an object to be measured, a spatial area, or a liquid. For instance, the measurement environment could be the surface of a motor, such as an electric motor, or another component of an electric vehicle.

[0019] For temperature measurement, the sensor is placed in the measurement environment. For example, the sensor can be inserted into a recess of the object to be measured. In this case, the sensor, or rather the measuring element, assumes the temperature of the measurement environment.

[0020] The measuring element preferably comprises an electrical component whose electrical properties, such as its electrical resistance, change with temperature. The electrical resistance of the measuring element can be determined externally via the connecting cables, thus enabling the temperature of the measurement environment to be measured.

[0021] The sensor described here can be adapted particularly easily and independently of the first potting at the first end, i.e., in the measuring area where the sensing element is located. This allows a material with relatively high thermal conductivity to be used for the second potting. Furthermore, the second potting can have a smaller cross-section than the first, thus reducing the thermal mass at the first end. This reduces the sensor's response time and enables a more accurate measurement result in a shorter time. The response time, in particular, indicates the time required for the sensing element to register a reading.

[0022] Essentially, it assumes the temperature of the measurement environment.

[0023] At the same time, the sensor can be adapted to a specific application. For example, if the sensor is used in an environment with high currents or voltages, the material or geometric shape of the second encapsulation can be adjusted accordingly to achieve the required insulation resistance for the sensor.

[0024] In a preferred embodiment, the sensor has a smaller cross-sectional area at the first end than at the second end. A sectioning plane in which the respective cross-sectional area lies is, for example, perpendicular to a principal direction of extension of the sensor. The sectioning plane at the first end is, in particular, a section through the first potting layer. The sectioning plane at the second end is, in particular, a section through the second potting layer.

[0025] The cross-sectional area at the second end has, for example, a length and width of between 1 mm and 4 mm. For instance, the cross-sectional area at the second end has a length of 2 mm and a width of 2 mm. The cross-sectional area at the second end can be rectangular, particularly square, or elliptical or circular. Preferably, the cross-sectional area at the second end is rectangular with rounded corners.

[0026] The cross-sectional area at the first end has, for example, a length and width of between 2.5 mm and 7 mm. For example, the cross-sectional area at the first end has a length of 4 mm and a width of 4 mm. The cross-sectional area at the first end can be rectangular, in particular square, or elliptical or circular. Preferably, the cross-sectional area at the first end is rectangular with rounded corners.

[0027] The smaller cross-sectional area at the second end reduces the thermal mass of the sensor in the area of ​​the measuring element, thus shortening the response time. Simultaneously, the initial potting compound at the first end can be large enough to ensure a stable and tight connection to the connecting cable.

[0028] In another embodiment, the minimum thickness of the second encapsulation between the measuring element and an outer surface is at most 0.7 mm or at most 0.5 mm. For example, the thickness is between 0.2 mm and 0.4 mm or between 0.1 mm and 0.3 mm. The outer surface is, in particular, a surface of the sensor that is accessible from the measuring environment. The minimum thickness is thus, in particular, a minimum wall thickness of the second encapsulation. A small thickness can advantageously shorten the response time of the sensor. At the same time, the thickness can be selected to meet requirements regarding the insulation resistance or temperature resistance of the sensor.

[0029] According to one embodiment, a first central axis of the first potting is identical or substantially identical to a second central axis of the second potting. The central axes can be axes of symmetry of the respective potting. The central axes preferably extend parallel to the main direction of extension of the sensor. For example, the central axes coincide with each other within a manufacturing tolerance. Alternatively, it is possible that the central axes are offset from each other by a defined distance.

[0030] The sequential formation of the first and second castings advantageously allows for precise positioning of the second casting relative to the first. This enables targeted alignment of the central axes.

[0031] In a preferred embodiment, the first potting compound extends from the transition region to the first end, and the second potting compound extends from the transition region to the second end. This means, in particular, that the sensor, in a section between the transition region and the first end, includes the first potting compound and is preferably free of the second potting compound. Preferably, the first end is free of the second potting compound. Furthermore, in a section between the transition region and the second end, the sensor, in particular, includes the second potting compound and, in this section, is preferably free of the first potting compound. Preferably, the second end is free of the first potting compound.

[0032] According to another preferred embodiment, the first casting and the second casting have different materials. For example, the first casting and the second casting differ in at least one material.

[0033] Possible materials for the first and second encapsulation include resins, plastics, and castable plastics. Preferably, materials for the first and second encapsulation have high temperature resistance, for example, up to 220°C or higher. It is possible that the first and / or second encapsulation comprises a matrix material in which particles are embedded. The matrix material is preferably a resin or a castable plastic. The particles are preferably electrically non-conductive and can influence the physical properties of the first / second encapsulation material. For example, the particles can be used to improve the thermal conductivity of the first / second encapsulation.

[0034] Particularly preferred are all materials used for the first and second potting that are free of per- and polyfluorinated alkyl compounds, also known as PEAS.

[0035] According to another version, at least one of the castings is transparent. This means, in particular, that the first casting, the second casting, or both the first and second castings are transparent. For example, a material is transparent for at least one of the castings.

[0036] Preferably, at least the first potting layer is transparent. A transparent first and / or second potting layer allows for visual inspection during sensor manufacturing.

[0037] In a further development, the second potting compound has a T-shaped cross-section through the transition area. This cross-section is, for example, perpendicular to the sensor's main direction of extension. Specifically, the vertical line of the T is in contact with the first potting compound. This creates an intermediate area between the transverse line of the T and the first potting compound. This geometric shape of the first potting compound in the transition area allows the sensor to be easily gripped by a gripping tool and mounted in an application.

[0038] Alternatively or additionally, the second casting in the cross-section through the transition area has the shape of a triangle or rectangle or paraboloid or ellipsoid or semicircle.

[0039] Alternatively, the second potting compound in the cross-section through the transition area can have the shape of a hook. This geometric shape of the first potting compound in the transition area allows the sensor to be gripped particularly easily by a gripping tool and mounted in an application.

[0040] The shape of the second potting compound in the transition area can serve as a marking or mounting feature for the sensor. For example, the marking can identify the sensor, indicating its physical properties, materials used, geometric shape, or measuring element. As a mounting feature, the second potting compound can improve the sensor's handling. For instance, gripping tools or similar implements can engage with the mounting features to position the sensor or guide it for further processing.

[0041] In another embodiment, the measuring element incorporates an NTC component. An NTC component is an electronic component with a negative temperature coefficient. An NTC component is also known as a thermistor. In this

[0042] Due to its design, the electrical resistance of the measuring element changes with its temperature. In particular, the resistance decreases with increasing temperature. The measuring element is preferably a thermistor.

[0043] The measuring element exhibits a known temperature-resistance characteristic curve, and thus a known relationship between resistance and temperature. During sensor operation, the measuring element assumes the temperature of the measurement environment and changes its resistance accordingly. The resistance of the measuring element can be determined via the connecting cables, and thus the temperature of the measurement environment can be measured.

[0044] According to at least one further embodiment, the connecting cable(s) each have an inner conductor and a sheath. The first potting compound is preferably in direct contact with the sheath. The inner conductor comprises, for example, copper. The sheath comprises, for example, plastic.

[0045] The measuring element is preferably connected to each connecting cable via at least one connecting wire. A connection point between the connecting wire and the connecting cable is located within the first potting compound. The connecting wire comprises, for example, copper.

[0046] At the connection point, for example, the inner conductor of the connecting cable is exposed. The inner conductor is connected to the connecting wire, for example, by means of a solder connection.

[0047] In a preferred embodiment, the sensor is configured to detect the temperature of a motor, an electric motor or a component of an electric vehicle.

[0048] The electric vehicle can be any type of electric vehicle. In particular, the electric vehicle can be an electric passenger car. The electric passenger car can be a battery electric vehicle (BEV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV). The electric passenger car can be any type or category of electric vehicle, also known as an XEV.

[0049] It is possible that the temperature sensor is designed to detect the temperature of an electromechanical component.

[0050] Furthermore, a method for manufacturing a sensor is specified. In particular, the method is used to manufacture a sensor as described herein according to one or more embodiments. That is to say, all features disclosed with respect to the sensor are also disclosed with respect to the method and vice versa.

[0051] In this process, a measuring element, connected to at least one connecting cable via at least one connecting wire, is provided in one step. The measuring element is, for example, an NTC component and includes a thermistor. In a subsequent step, a first potting is formed, bringing the connecting cable into direct contact with the first potting and enclosing a connection point between the connecting wire and the connecting cable. The first potting is formed, for example, in a casting step. In this step, the connection point is placed in a first casting mold and then potted.

[0052] In a subsequent step of the process, a second potting compound is formed. This second potting compound is formed such that it directly adjoins the first in a transition zone, and the measuring element is at least partially enclosed by the second potting compound. Preferably, the measuring element is directly adjacent to the second potting compound. The second potting compound is formed, for example, in a single casting step. In particular, the first potting compound is placed into a second mold and then cast.

[0053] The steps of the procedure are preferably carried out in the specified order.

[0054] In particular, the first and second pottings are formed independently and sequentially in this process. For example, the process comprises two potting steps, in which the first potting is produced in the first step. In the second potting step, the second potting is produced, with the first potting being used for precise positioning during the second potting step. The first and second pottings are specifically designed such that the measuring element is located at a first end of the sensor and the connecting cable is located at a second end of the sensor. The first end and the second end are, for example, opposite ends of the sensor. A principal extension direction of the sensor is, for example, a direction from the first end to the second end.

[0055] In at least one embodiment of the process, the first casting is formed by a casting process using a first mold, and the second casting is formed by a casting process using a second mold. The first and / or second mold comprises, for example, silicone rubber or polytetrafluoroethylene (PTFE).

[0056] To form the second casting, the first casting is preferably partially inserted into the second mold. In doing so, the first casting is brought into direct contact with the second mold, at least partially. This allows for precise positioning of the first casting, enabling the second casting to be produced precisely in relation to the first.

[0057] Preferably, the first mold has a first recess. The first recess defines, for example, the outer shape of the first casting.

[0058] The second mold preferably has a second recess. The second recess preferably has a first region with a first cross-sectional area and a second region with a second cross-sectional area. The second cross-sectional area is particularly smaller than the first cross-sectional area. The first cross-sectional area corresponds, for example, to a cross-sectional area of ​​the first recess of the first mold.

[0059] For example, the first casting is introduced into the first area when forming the second casting. Thus, the first area of ​​the second recess serves primarily to precisely position the first casting. In particular, the second area of ​​the second recess determines the geometric shape of the second casting. That is, the cross-sectional area and wall thickness of the second casting can be adjusted via the second area of ​​the second mold.

[0060] The second casting mold can have an overflow channel that is directly adjacent to the first casting during the formation of the second casting and is at least partially filled with material from the second casting. The material for the second casting is, for example, a casting compound from which the second casting is produced.

[0061] For example, the overflow channel is arranged on an inwardly facing side surface of the second casting mold. Preferably, the overflow channel is arranged on a side wall of the second recess, for example, in the first area. During the formation of the second casting, the material or casting compound for the second casting can rise into the overflow channel. This allows for an increased tolerance range for the casting compound of the second casting. The overflow channel can have a cross-section that corresponds to a geometric shape of the second casting in the transition area. That is, the shape of the assembly features or markings can be defined by the overflow channel.

[0062] Further advantages and beneficial embodiments and developments of the sensor and the method for manufacturing the sensor will become apparent from the exemplary embodiments presented below in conjunction with schematic drawings. Identical, similar, and similarly functioning elements are designated with the same reference symbols in the figures. The figures and the relative sizes of the elements depicted in the figures are not necessarily to be considered as being to scale. Rather, individual elements may be exaggerated for clarity and / or better understanding.

[0063] They show:

[0064] Figure 1 shows a sensor described here according to a first embodiment in perspective view ,

[0065] Figures 2 and 3 show the sensor according to the first embodiment in different side views,

[0066] Figure 4 shows the sensor according to the first embodiment in a perspective view, Figure 5 shows a detailed view of the sensor according to the first embodiment in a schematic sectional view.

[0067] Figures 6 to 10 show detailed views of a sensor described here according to several exemplary embodiments in schematic sectional view.

[0068] Figures 11 and 12 show a first mold for a method for manufacturing a sensor described herein according to an exemplary embodiment in different views.

[0069] Figures 13 and 14 show a second mold for a method for manufacturing a sensor described herein according to an exemplary embodiment in different views.

[0070] Figure 1 shows a sensor 1 described herein according to a first embodiment. The sensor 1 comprises two connecting cables 3 at a first end 11. The connecting cables 3 are in direct contact with a first potting compound 4. In a transition area 13, the first potting compound 4 is in direct contact with a second potting compound 5. A principal extension direction of the sensor 1 runs from the first end 11 to the second end 12. At the first end 11, the sensor 1 is free of the second potting compound 5. At the second end 12, the sensor 1 is free of the first potting compound 4.

[0071] The first casting 4 and the second casting 5 comprise, for example, a resin or a castable plastic. As can be seen from the side views in Figures 2 and 3, the first casting 4 has a width 43 and a length 44. The second casting 5 has a width 53 and a length 54. The width 43 and length 44 of the first casting 4 are each larger than the width 53 and length 54 of the second casting 5. For example, the width 43 and length 44 of the first casting 4 are each 4 mm, and the width 53 and length 54 of the second casting 5 are each 2 mm. Thus, the first casting 4 has a larger cross-sectional area at its first end 11 than the second casting 5 has at its second end 12. The cutting plane of the cross-sectional area is determined perpendicular to the main extension direction and by the width 43, 53 and length 44, 54.

[0072] Figure 4 shows a perspective view of Figure 1, with the outer surfaces of sensor 1 depicted as semi-transparent. Sensor 1 comprises a sensing element 2, which is connected to the connecting cables 3 via connecting wires 21. The sensing element 2 is an NTC component whose electrical resistance is temperature-dependent and decreases with increasing temperature. The sensing element 2 specifically comprises a thermistor. The connecting wires 21 comprise, for example, copper.

[0073] The connecting cables 3 each comprise an inner conductor 33, which is made of copper, for example, and a sheath 34, which is made of plastic, for example. At a connection point 20, which lies within the first potting compound 4, the inner conductors 33 are exposed and electrically connected to the connecting wires 21. For example, the electrical connection is a solder joint. The sensor 1 is configured for temperature detection. During operation, the sensor 1 detects, for example, the temperature of a measurement environment. The measurement environment can be an object to be measured, such as a motor, an electric motor, or another component of an electric vehicle. The sensor 1 is, in particular, a so-called temperature sensor.

[0074] For temperature measurement, sensor 1 is brought into contact with the object to be measured. Sensor 1, or rather the measuring element 2, then assumes the temperature of the object being measured. The electrical resistance of the measuring element 2 adjusts accordingly to the temperature of the object being measured. Given a known relationship between temperature and electrical resistance, the temperature of the object can then be determined from the electrical resistance of the measuring element 2. The electrical resistance of the measuring element 2 can be determined, in particular, via the connecting cables 3.

[0075] The sensor 1 described here has, among other advantages, that the second potting compound 5 can be produced independently of the first potting compound 4. For example, the potting compounds 4 and 5 can be produced sequentially using independently executed casting processes. The first potting compound 4 can be used for precise positioning during the formation of the second potting compound 5, resulting in the center axes 40 and 50 of the potting compounds 4 and 5 being essentially identical. This means that the sensor 1 can be manufactured with high precision.

[0076] Furthermore, the second potting compound 5 can be designed with a comparatively small cross-sectional area. This allows the thermal mass of the sensor 1 at the first end 11, which represents a measuring area of ​​the sensor 1, to be kept small. This advantageously reduces the response time of the sensor 1 and allows the measuring element 2 to reach thermal equilibrium with the object being measured or the measuring environment more quickly.

[0077] Similarly, the material of the second potting 5 can be chosen largely independently of the material of the first potting 4 in order to increase thermal conductivity and thus reduce response time.

[0078] As illustrated in Figure 5, the minimum thickness 51 between the measuring element 2 and an outer surface 52 of the second potting compound is relatively small, for example 0.5 mm or less. With a relatively small minimum thickness 51, the response time can be further reduced.

[0079] At the same time, the material and geometry of the sensor 1, in particular of the second potting 5, can be chosen such that the sensor 1 meets requirements regarding insulation strength or high-voltage strength.

[0080] Figures 6 to 10 show a cross-section of the transition region 13 of different embodiments of the sensors 1 described here. The cutting planes of the cross-sections are in particular perpendicular to the main extension direction of the corresponding sensors 1.

[0081] Figure 6 shows in particular a cross-section through the sensor 1 according to the first embodiment.

[0082] In the transition area 13, the first potting compound 4 borders the second potting compound 5. In the embodiment shown in Figure 6, the second potting compound 5 has a geometric T-shape. The vertical line of the T is in direct contact with the first potting compound 4.

[0083] Alternatively, the second casting 5 can have the shape of a rectangle (Figure 7), a triangle (Figure 8), a paraboloid (Figure 9) or a hook (Figure 10).

[0084] The shape of the second potting compound 5 in the transition area 13 can be a marking or a mounting feature for the sensor 1. For example, the marking can identify the sensor 1, for instance, with regard to its physical properties, materials used, geometric shape, or the measuring element 2 used. As a mounting feature, the second potting compound 5 can improve the handling of the sensor. Gripping tools or the like can engage with the mounting features and thus position the sensor or guide it for further processing. The use of gripping tools is particularly relevant in the embodiments shown in Figures 6 and 10.

[0085] Figure 11 shows a schematic sectional view of a first mold 100, which can be used in a method described herein for manufacturing a sensor 1 according to one embodiment. Figure 12 shows a top view of the first mold 100. The method is used, for example, to manufacture a sensor 1 according to the first embodiment.

[0086] The first casting 4 is produced using the first mold 100. For this purpose, the connecting cables 3 are inserted into the first mold 100 and cast in a single pouring step. The first mold 100 has a first recess 101. The first recess 101 has a length and a width that essentially correspond to the length 43 and width 44 of the first casting 4 (Figure 12). Thus, the first mold 100 can define the geometric shape of the first casting 4. After casting and subsequent curing, the first casting 4 is produced, and the first mold 100 can be removed. Curing is achieved, for example, by heat, light, or chemical means. The first mold 100 comprises, for example, silicone rubber or polytetrafluoroethylene (PTFE).

[0087] Figure 13 shows a schematic sectional view of a second mold 110, which can be used in a method described herein for manufacturing the sensor 1 according to the present exemplary embodiment. Figure 14 shows a top view of the second mold 110. The second mold 110 comprises, for example, silicone rubber or polytetrafluoroethylene (PTFE).

[0088] The second casting 5 is produced using the second casting mold 110. For this purpose, the first casting 4 is at least partially inserted into the second casting mold 110 and cast in a single pouring step. Advantageously, this allows the first casting 4 to be precisely positioned during the production of the second casting 5.

[0089] The second casting mold 110 has a second recess 111.

[0090] The second recess 111 has a first area 112 and a second area 113. The first casting 4 is inserted into the first area 112 during the process.

[0091] Area 112 has the second recess 111 with a length and width corresponding to the length 44 and width 43 of the first casting 4. This allows the first casting 4 to be precisely placed in the second casting mold 110. In particular, the first casting 4 is abutting the second casting mold 110 in the first area 112, i.e., at least partially in direct contact with the second casting mold 110.

[0092] In the second area 113, the second recess 111 has a width and a length that essentially correspond to the width 53 and length 54 of the second casting 5. Thus, the geometric shape of the second casting can be defined by the second mold 110. During the formation of the second casting 5, the measuring element 2 is inserted and cast into the second area 113 of the second recess 111. After the measuring element 2 has been cast and the casting has cured, the second casting 5 is complete, and the second mold 110 can be removed. Curing can be achieved, for example, by heat, light, or chemical means.

[0093] In the first area 112, the second recess 111 has overflow channels 115 on its inner side surfaces. Excess potting compound for the second potting 5 can rise into the overflow channels 115 during the production of the second potting 5. This allows the tolerance range for the potting compound of the second potting 5 to be increased and the second potting 5 to be manufactured precisely.

[0094] The overflow channels 115 have a cross-section that corresponds to a geometric shape of the second casting 5 in the transition area 13. This means that the shape of the mounting features or markings can be defined by the overflow channels 115 (Figures 6 to 10). The invention is not limited to the description based on the exemplary embodiments. Rather, the invention encompasses every new feature as well as every combination of features, which in particular includes every combination of features in the claims, even if this feature or combination itself is not explicitly specified in the claims or exemplary embodiments.

[0095] Reference sign

[0096] 1 sensor

[0097] 2 measuring element

[0098] 3 connection cables

[0099] 4 first casting

[0100] 5 second potting

[0101] 11 first end

[0102] 12 second end

[0103] 13 Transition area

[0104] 20 liaison point

[0105] 21 Connecting wire

[0106] 33 inner conductors

[0107] 34 Coat

[0108] 40 first central axis

[0109] 43 width

[0110] 44 Length

[0111] 50 second central axis

[0112] 51 Thickness of the second casting

[0113] 52 outdoor area

[0114] 53 width

[0115] 54 Length

[0116] 100 first casting mold

[0117] 101 first exception

[0118] 110 second casting mold

[0119] 111 second exception

[0120] 112 first area of ​​the second recess

[0121] 113 second area of ​​the second recess

[0122] 115 Overflow channel

Claims

Patent claims 1. Sensor (1) for temperature detection, comprising a measuring element (2), at least one connecting cable (3) for contacting the measuring element (2), a first potting (4) and a second potting (5), wherein the connecting cable (3) is arranged at a first end (11) of the sensor (1) and is in direct contact with the first potting (4), the measuring element (2) is arranged at a second end (12) of the sensor (1), is at least partially surrounded by the second potting (5) and is in direct contact with the second potting (5), and in a transition area (13) between the first end (11) and the second end (12) the first potting (4) is in direct contact with the second potting (5).

2. Sensor (1) according to claim 1, wherein the sensor (1) has a smaller cross-sectional area at the first end (11) than at the second end (12).

3. Sensor (1) according to claim 1 or 2, wherein a minimum thickness (51) of the second potting (5) between the measuring element (2) and an outer surface (52) is at most 0.5 mm.

4. Sensor (1) according to one of the preceding claims, wherein a first central axis (40) of the first potting (4) coincides with a second central axis (50) of the second potting (5).

5. Sensor (1) according to one of the preceding claims, wherein the first potting compound (4) is separated from the transition area (13) to the first end (11) and the second casting (5) extends from the transition area (13) to the second end (12).

6. Sensor (1) according to one of the preceding claims, wherein the first potting (4) and the second potting (5) comprise different materials.

7. Sensor (1) according to one of the preceding claims, wherein at least one of the pots (4, 5) is transparent.

8. Sensor (1) according to one of the preceding claims, wherein the second potting compound (5) has the shape of a T at least in a cross-section through the transition area (13).

9. Sensor (1) according to one of claims 1 to 7, wherein the second potting compound (5) has the shape of a rectangle at least in a cross-section through the transition area (13).

10. Sensor (1) according to one of claims 1 to 7, wherein the second potting compound (5) has the shape of a triangle at least in a cross-section through the transition area (13).

11. Sensor (1) according to one of claims 1 to 7, wherein the second potting compound (5) has the shape of a paraboloid at least in a cross-section through the transition region (13).

12. Sensor (1) according to one of claims 1 to 7, wherein the second potting compound (5) has the shape of a hook at least in a cross-section through the transition area (13).

13. Sensor (1) according to one of the preceding claims, wherein the measuring element (2) comprises an NTC component.

14. Sensor (1) according to one of the preceding claims, wherein the connecting cable (3) comprises an inner conductor (33) and a sheath (34) and the first potting compound (4) is in direct contact with the sheath (34).

15. Sensor (1) according to one of the preceding claims, wherein the measuring element (2) is connected to the connecting cable (3) via at least one connecting wire (21) and a connection point (20) between the connecting wire (21) and the connecting cable (3) is arranged within the first potting (4).

16. Sensor (1) according to one of the preceding claims, wherein the sensor (1) is configured to detect the temperature of a motor, an electric motor or a component of an electric motor vehicle.

17. Method for manufacturing a sensor (1) for temperature detection, comprising the steps: - Providing a measuring element (2) which has at least one connecting wire (21) with at least one connecting cable (3) is connected - Forming a first potting (4) so ​​that the connecting cable (3) is in direct contact with the first potting (4) is brought and a connection point (20) between the connecting wire (21) and the connecting cable (3) is enclosed, - Forming a second potting (5) such that the second potting (5) is directly adjacent to the first potting (4) in a transition area (13) and the measuring element (2) is at least partially enclosed by the second potting (5).

18. Method according to claim 17, wherein the first casting (4) is formed by a casting process using a first mold (100) and the second casting (5) is formed by a casting process using a second mold (110) and, in order to form the second casting (5), the first casting (4) is at least partially introduced into the second mold (110) and the first casting (4) is brought at least partially into direct contact with the second mold (110).

19. Method according to claim 18, wherein the first mold (100) has a first recess (101) and the second mold (110) has a second recess (111), the second recess (111) having a first area (112) with a first cross-sectional area and a second area (113) with a second cross-sectional area that is smaller than the first cross-sectional area, and the first cross-sectional area corresponds to a cross-sectional area of ​​the first recess (101) of the first mold (100).

20. Method according to claim 18 or 19, wherein the second mold (110) has at least one overflow channel (115) which is directly adjacent to the first casting (4) during the formation of the second casting (5) and is at least partially filled with a material of the second casting (5).

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