KR20150145188A - Temperature measuring device for detecting temperature of a flowing fluid medium - Google Patents

Abstract

The present invention relates to a temperature measuring device (10) for detecting the temperature of a flowing fluid, which is to be used particularly in a vehicle. The temperature measuring device (10) comprises at least one temperature probe (32) and a housing (12). The housing (12) comprises a measuring port (16). The housing (12) regulates the longitudinal extension direction (48). The temperature probe (32) is at least partially inserted in the measuring port (16). The measuring port (16) is vertically extended in the longitudinal extension direction (48) of the housing (12) along an extension shaft (46). The measuring port (16) comprises an opening (28) and the opening is at least partially limited by a strut (30). The strut (30) is substantially disposed in parallel with the extension shaft (46). The strut (30) has a profile string (50) on a section which is perpendicular to the extension shaft (46). The measuring port (16) comprises two struts (30) and the struts are disposed in a method such that the profile string (50) may be biased to the main flow direction (18) of a flow in a section perpendicular to the extension shaft (46).

Description

TECHNICAL FIELD [0001] The present invention relates to a temperature measuring apparatus for detecting a temperature of a flowing fluid,

The present invention relates to a temperature measuring device for detecting the temperature of a flowing fluid.

One or more characteristics of the fluid must be detected in various technical fields such as, for example, natural sciences or medical engineering. The characteristics may basically relate to any physical and / or chemical properties of the fluid, i.e., gas and / or liquid, such as temperature, pressure, fluidity, and the like. An important example is the detection of fluid temperature, but the present invention is not limited to this. The following relates to a temperature measuring device, which can be used in automobiles in particular. Such temperature sensors are disclosed, for example, in Konrad Reif (publisher): In-Vehicle Sensors, 1st Edition 2010, page 137. The measurement principle described therein can basically be used within the scope of the present invention. However, other uses are basically possible.

DE 10 2009 026 472 A1 discloses a temperature measuring device with a measuring probe for use with, for example, another measuring probe for pressure detection.

The temperature measurement probe used may be, for example, a so-called NTC, i.e. a temperature dependent resistor with a negative temperature coefficient, and the electrical resistance of the NTC varies with temperature, especially with increasing temperature. These NTCs typically include glass or plastic beads having a diameter of 1 to 4 mm, and two pins, electrical connections, protrude from the beads.

Despite the improvements realized by these temperature measuring devices, the optimization potential of the disclosed temperature measuring devices still exists. Therefore, a low-pressure sensor for measuring the supply air pressure usually has additional temperature sensors, such as NTC, for example. The temperature sensor or the temperature probe protrudes into the intake manifold through the measurement port and serves to measure the temperature of the fluid without delay. To protect the NTC during assembly and operation, the NTC is primarily mounted within a so-called protective cage of the measurement port. Up until now, only relatively large and relatively slow NTCs have been used because of their thermal inertia and epoxy cover. The two ends of the NTC are fixed, and the cage includes the measurement head and the connection line. Due to this, the NTC-cage should be well blocked by its size and design around the measurement head and the connection line, and therefore should also be helpful for temperature signals with a large response time other than the slow NTC.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a temperature measuring device for detecting the temperature of a flowing fluid, in particular for use in a motor vehicle, which at least substantially avoids the disadvantages of the disclosed temperature measuring device. In particular, a temperature measuring device is to be provided which makes it possible, for example, to use a small temperature probe made of glass with a thin and smooth connection line. In addition, optimal contact protection and assembly protection must be ensured and the response time of the temperature probe must be optimized.

The above object is solved by a temperature measuring apparatus according to claim 1.

A temperature measuring apparatus according to the present invention for detecting a temperature of a flowing fluid, particularly for use in an automobile, includes at least one temperature probe and a housing. The housing includes a measurement port. The housing defines a longitudinal direction of extension. The temperature probe is inserted at least partially into the measurement port. The measuring port extends perpendicularly to the longitudinal direction of the housing along the extension axis. The measuring port includes an opening, said opening being at least partially confined by struts. The struts are disposed substantially parallel to the extension axis. The strut has a profile string in its cross-section perpendicular to the extension axis. The measurement port includes two struts, in which case the profile string is deflected relative to the main flow direction. For example, the two struts are arranged so that the profile string is disposed at an angle of 30 to 60 degrees with respect to the longitudinal extension direction.

The strut may have an oval cross-section. The temperature probe may comprise a connection line, in which case the opening is formed such that at least in part the fluid can flow into the connection line. The connection lines may be fixed in at least two positions. The temperature probe may comprise a measuring head, in which case the connecting lines are fixed near the end remote from the measuring head and near the measuring head. Struts can be thicker than the measuring head. Struts may have a thickness, for example, and the measuring head has a diameter, in this case the ratio of thickness to diameter is 1.0 to 2.0. The measurement port may include a guide channel for insertion of the temperature probe. The guide channel may have a guide channel diameter, in which case the ratio of the guide channel diameter to the diameter of the measuring head is 1.05 to 1.25. The guide channel may have an at least partially elliptical cross-section. The guide channel may be tapered in a funnel shape in a direction away from the housing. The strut may protrude from the housing more than the temperature probe.

Is a Fortran short tubular connection in the context of the present invention. Since the ports protrude into the fluid and measure the temperature there, the ports are referred to as measurement ports in the context of the present invention. Since the fluid generally has a pressure above atmospheric or normal pressure, and therefore the port must have a certain pressure resistance, the port is particularly touted as a pressure port in a combined pressure and temperature measuring device. These pressure ports are measurement ports in the context of the present invention.

The profile string is a hypothetical connection line between the profile nose and the profile back edge of the profile in the context of the present invention, where the profile of the cross-section of the body in the flow direction in accordance with the general definition of fluid dynamics is called a profile.

The main flow direction is the local flow direction of the fluid at the location of the temperature measuring device in the context of the present invention, in which case local irregularities such as, for example, turbulence may not be considered. Thus, in particular, the main flow direction may be the local average transport direction of the flowing fluid.

The angle of attack is the angle between the profile stream of the strut located furthest upstream and upstream of the main flow direction of the incoming fluid in the context of the present invention. Of course, the angle of attack can also be determined for a measuring port with multiple struts. In this case, the angle of attack is related to the imaginary position of the associated strut furthest upstream from all other struts, from the strut located farthest upstream, which may be referred to as the first strut, i.e. the theoretical angle of attack of the other strut , The associated strut is rotated to be located at the farthest position upstream of the first strut. This is particularly important where, for example, a plurality of struts are provided circumferentially about the temperature probe, thereby providing a different flow of fluid as viewed over the basic arrangement of struts. Thus, for the actual definition of the angle of attack, the strut has to be theoretically rotated to the position of the first strut as opposed to the main flow direction, as described above.

In the context of the present invention, the shape of an elongated hole refers to a shape in which longitudinal side faces extend parallel to each other and the short side ends by a semicircle, and the diameter of the semicircle corresponds to the width of the shape or the spacing of longitudinal side faces.

The temperature probe is a temperature sensor of all kinds disclosed in the context of the present invention, in particular a so-called NTC, i.e. a temperature dependent electrical resistance with a negative temperature coefficient, the electrical resistance of which varies with temperature, . However, the electrical resistance with the PTC, i. E., The constant temperature coefficient may be considered, and the resistance of the PTC increases with increasing temperature. For another possible formation of such a pressure sensor, reference can be made to the above prior art, in particular to Konrad Reif (publisher): In-Vehicle Sensor, First Edition 2010, page 137. However, other embodiments are basically possible.

In the context of the present invention, a pressure sensor element is an element that transmits an actual measurement signal to a measurement value used to detect pressure and / or fluid pressure. As is common in pressure sensors, for example, a pressure sensor element includes a sensor membrane formed as a measurement bridge, and the sensor membrane includes one or more piezoresistive elements and / or other types of sensitive elements. The pressure sensor element may comprise, for example, a glass base and a silicon chip disposed on the glass base, and may be constructed of piezo resistive resistive elements, for example, in the form of a Wheatstone bridge on the surface of the silicon chip An evaluation circuit is provided. The membrane required for pressure detection can be manufactured by etching the back surface of the silicon chip. Since the connection between the silicon chip and the glass base is performed, for example, in a vacuum state, the inside of the etched hole is also evacuated. For another possible formation of such a pressure sensor element, for example, Konrad Reif (publisher): In-Vehicle Sensor, First Edition 2010, pages 134-136 can be referred to. However, other embodiments are basically possible.

The basic idea of the present invention is based on the fact that most of the heat input and output at the temperature change of the fluid to be measured is removed through the connection line of the temperature probe. For example, when the fluid to be measured is heated, the connection line is heated and the connection line transfers heat to the ceramic in or on the measuring head. Thus, a rapid temperature signal is preferred, a good inflow of the connection line and a small temperature probe as a whole are important. The contact protector for the temperature probe in the present invention is designed to return the connection line without interruption at all times when the fluid, for example, air, is passed through the port in the longitudinal direction of the housing, . Due to the special shape of the struts as the two elliptical contact protections, no disturbing deat water zone is formed, with low flow rates and low heat transfer. The fluid always flows optimally into this important connection line for heat transfer.

Another basic idea of the present invention is that the temperature probe is fixed at two points instead of being separated in the actual measurement port by being fixed only to the end remote from the measurement head as in the disclosed temperature measurement device. For example, a temperature probe is secured to the bond between the sensor module and the housing and to the clamping portion of the connection line just above the measurement head. This allows the temperature probe to move in only a very short range, making the connection more robust overall and significantly reducing the vibration load on the temperature probe and connection line.

At the bottom of all low-pressure sensors, a port with contact protection for O-rings, temperature probes and temperature probes is placed. During the final assembly, the temperature probe is first bent and then inserted into the empty sensor housing from above. The temperature probe also slides along the guide wall within the sensor. The measuring head slides through the guide hole, and the connecting line is fixed in the guide hole. Subsequently, the sensor is electrically contacted, e.g. welded or brazed, and passivated by a module adhesive. The temperature probe is mechanically fixed by clamping and by welding or soldering from above.

What is important for assembly within the sensor housing is a smooth guide wall, which forms a funnel with the remaining housing, and the funnel receives the temperature probe. The outline of the guidewall is nearly elliptical with a minimum diameter slightly larger than the diameter of the measuring head of the temperature probe. This shape allows the connection line to slip spontaneously into its final position during assembly.

 The contact protector is designed such that two wing-like webs are arranged at about 45 degrees with respect to the longitudinal axis of the sensor because the flow direction in which the sensor is exposed is located in the sensor longitudinal direction or rotated about 90 degrees to be. The connecting line and the measuring head are not completely shielded by the rotated arrangement. They are not located in the trailing region of the contact protection. Also, the port can be removed relatively easily when implemented as an injection molded part. The individual contact lines of the contact protector have approximately the same thickness as the temperature probe and protrude further into the flow than the temperature probe, thereby ensuring mechanical protection during assembly and operation.

Other optional details and features of the invention are set forth in the following description of a preferred embodiment, which is schematically illustrated in the drawings.

1 is a perspective view of a temperature measuring apparatus according to the present invention;
2 is a bottom view of the temperature measuring device.
3 is a cross-sectional view of the guide channel of the measurement port of the temperature measuring device.
4 is a planar perspective view of the temperature measuring device.
5 is a cross-sectional view of the temperature measuring device.
Figure 6 is another cross-sectional view of a temperature measuring device rotated 90 ° relative to Figure 5;

1 shows an exploded view of a temperature measuring device 10 according to the invention for detecting the temperature of a flowing fluid. The temperature measuring device 10 may be formed as a combined pressure-temperature sensor. Since the present invention can be used in the automotive technology field in particular, the temperature measuring device 10 according to the present invention can be installed, for example, in an intake manifold of an internal combustion engine, . Other applications where the temperature of the fluid and optionally the pressure or other parameters must be determined are also possible.

The temperature measurement apparatus 10 includes a housing 12 and a measurement port 16, which can be closed by a housing cover 14, and the measurement port can be formed as a pressure port. The measurement port 16 protrudes into the flowing fluid and is refluxed by the fluid in the main flow direction 18 (FIG. 2). The measurement port 16 has a lower end portion 20 and an upper end portion 22. The measuring port 16 has a sealing ring 26, for example a groove 24 for an O-ring, in the upper part 22 located closer to the housing 12 than the lower end 22, The housing 12 can be sealed. The measurement port 16 is formed in a cage shape and includes an opening 28 through which the fluid flowing through the opening can be introduced into the measurement port 16. The opening 28 is limited by two struts 30. A support portion may be provided inside the measurement port 16, and the support portion supports and stabilizes the temperature probe 32 accommodated therein.

The temperature probe 32 may be formed, for example, in the form of an NTC-resistor. The temperature probe 32 includes a measuring head 34 in the form of a glass or plastic bead having two electrical contacts 36 in the form of pins that can be bent. The measuring head 34 is formed in a ball shape and has a diameter of, for example, 1 mm to 4 mm. 1, the temperature probe 32 may be inserted from the side of the housing 12 remote from the measurement port 16. [ Correspondingly, the temperature probe 32 is at least partially inserted into the measurement port 16.

Inside the housing 12 the temperature probe 32 may be connected to the punching grid 38 (FIG. 5) of the sensor module 40 (FIG. 5) by a connection line 36. The sensor module 40 is a combined sensor module in the illustrated embodiment, which is formed for the detection of the pressure of the flowing fluid and for the detection of the temperature of the flowing fluid. Thus, the sensor module 40 includes a temperature probe 32 and a pressure sensor element 42 (FIG. 5). The sensor module 40 is disposed, for example, on the carrier 44 (FIG. 5) and is electrically connected to the carrier by, for example, bonding wires not shown in detail. The carrier 44 may also be electrically connected to the connection lines 36 of the punching grid 38 and the temperature probe 32 by bonding wires not shown. The carrier 44 can also be electrically connected to a connection contact (not shown) of the temperature measuring device 10, and the contact is guided out of the housing 12. As shown, the interior of the housing 12, in which the evaluation circuit and the rest of the electronic device are disposed, can be closed by the cover 14. The measurement port 16 is projected into the fluid along the extension axis 46 with the temperature measurement device 10 being installed in the measurement gas chamber containing the fluid by the housing 12. [ The strut 30 is in this case disposed substantially parallel to the extension axis 46. The measuring port 16 may be formed rotationally symmetric about the elongate axis 46 except for the strut 30. [

Fig. 2 shows a bottom view of the temperature measuring device 10. Fig. The housing 12 defines a longitudinal direction 48 having a dimension that extends parallel to the longest dimension of the housing 12. The temperature measuring device 10 is generally designed to measure the temperature of the intake air in such a manner that the longitudinal direction 48 is aligned parallel to or about 90 degrees to the main flow direction 18 in a cross- And assembled to the manifold. As can also be seen in FIG. 2, the strut 30 has an elliptical cross-section and a profile string 50, respectively, in a cross-section perpendicular to the extension axis 46. The profile string 50 is disposed biased relative to the main flow direction 18 within a cross-section perpendicular to the extension axis 46. The profile string 50 is disposed at an angle a of, for example, 30 째 to 60 째 and preferably 40 째 to 50 째 with respect to the longitudinal extension direction 48 at a cross section perpendicular to the extension axis 46. In this case, the arrangement is preferably at an angle? Of 45 degrees. The opening 28 is formed such that fluid is at least partially inflow into the connection line 36 as shown by the arrows. In other words, the openings 28 are arranged and dimensioned so that fluid can flow without interruption into the connection line 36.

The measurement port 16 includes a guide channel 52 for insertion of the temperature probe 32. Fig. 3 shows a bottom view or a cross-sectional view of the guide channel 52. Fig. The guide channel (52) has an elliptical cross section in the cross section perpendicular to the extension axis (46). The guide channel 52 has a guide channel diameter. The guide channel diameter is a dimension along a small half-axis in the form of an oval cross-section. The ratio of the guide channel diameter to the measuring head 34 diameter may be 1.05 to 1.25, and may be, for example, 1.10.

Fig. 4 shows a plan perspective view of the temperature measuring device 10. Fig. As will be described in more detail below, with reference to FIG. 4, the temperature probe 32 is inserted into the housing 12 and the measurement port 16 from above.

Fig. 5 shows a first cross-sectional view of the temperature measuring device 10. Fig. As can be seen in FIG. 5, the guide channels 52 are tapered in a funnel shape away from the housing 12. The strut 30 has a thickness. The thickness of the strut 30 is the largest dimension of the strut in the cross section perpendicular to the extension axis 46. The measuring head 34 has a diameter. The ratio of thickness to diameter may be 1.0 to 1.25, for example 1.05. As further seen in FIG. 5, the strut 30 protrudes from the housing 12 more than the temperature probe 32. This ensures mechanical protection during assembly and operation of the temperature measurement device 10. [

Fig. 6 shows a second cross-sectional view of the temperature measuring device 10. Fig. The second cross-sectional view is rotated by 90 degrees relative to the first cross-sectional view of Fig. As can be seen in Fig. 6, the connection line 36 is fixed in at least two positions 54,56. The connecting line 36 is fixed at a position 54 near the end remote from the measuring head 34 and is fixed at a position 56 near the measuring head 34. [ The connection line 36 is fixed to the position 54 between the pressure sensor 40 and the housing 12 on the one hand by the adhesive 58 and on the other hand by the clamping part 60 And is fixed at a position 56 just above the head 34. Fig. 6 also shows the assembly to the intake manifold 64. Fig. The alignment of the housing 12 in which the longitudinal extension direction 48 is parallel to the main flow direction 18 is shown.

The connecting line 36 of the temperature probe 32 is first bent in the section 62 (Figs. 3 and 5) remote from the measuring head 34 when assembling the temperature measuring apparatus 10. [ The temperature probe 32 is then inserted into the empty housing 12 and guide channel 52 from above. 5, the measuring head 34 of the temperature probe 32 slides in the guide channel 52 or along the wall of the guide channel 52. As shown in Fig. The measuring head 34 slides through the guide channel 52 and is clamped to the clamping portion 60 in the guide channel 52. Subsequently, the sensor module 40 is installed in an open manner in the housing 12. Finally, the temperature probe 32 is in electrical contact with, for example welded to, the sensor module 40 and is passivated at location 54 by a module adhesive. The temperature probe 32 is mechanically fixed to the position 56 by the clamping portion 60, to the position 54 by the bonding portion 58 and to the top by the welding portion.

10 Temperature measuring devices
12 Housing
14 Housing cover
16 Measuring port
18 Main flow direction
20 lower end
22 upper end
28 aperture
30 Struts
32 Temperature probe
36 connection line
40 sensor module
42 Pressure sensor element
46 Extension shaft
48 Longitudinal extension direction
50 profile strings
52 Guide channel

Claims (10)

A temperature measuring device (10) for detecting a temperature of a flowing fluid, in particular for use in an automobile, comprising at least one temperature probe (32) and a housing (12) Wherein the housing (12) defines a longitudinal direction (48) and the temperature probe (32) is at least partially inserted into the measuring port (16), the measuring port Extending perpendicularly to a longitudinal direction of the housing (12) along an extension axis (46), the measurement port (16) including an opening (28) Wherein the strut is disposed substantially parallel to the elongate shaft and the strut is defined by a profile string on the cross section perpendicular to the elongate axis. The temperature measuring apparatus according to claim 1,
The measurement port 16 includes two struts 30 which are arranged in the main flow direction 18 of the fluid flowing in the cross section perpendicular to the extension axis 46 The temperature measuring device being arranged so as to be biased with respect to the temperature measuring device. 2. The temperature measuring device according to claim 1, wherein the strut (30) has an elliptical cross section. 3. A method according to claim 1 or 2, wherein the temperature probe (32) comprises a connection line (36), the opening (28) being formed at least in part so that fluid can flow into the connection line And a temperature measuring device for measuring temperature. 4. The temperature measuring device according to claim 3, characterized in that the connection line (36) is fixed to at least two positions (54, 56). 5. The measuring head according to claim 4, wherein the temperature probe (32) comprises a measuring head (34), the connecting line (36) being located at a position (54) Is fixed to a position (56) near the second chamber (34). 6. The temperature measuring device according to claim 5, wherein the strut (30) has a thickness, the measuring head (34) has a diameter, and the ratio of the thickness to the diameter is 1.0 to 2.0. 7. The method according to any one of claims 1 to 6, wherein the measuring port (16) comprises a guide channel (52) for insertion of the temperature probe (32) , And the ratio of the diameter of the guide channel to the diameter of the measuring head (34) is 1.05 to 1.25. 8. The temperature measuring device according to claim 7, wherein the guide channel (52) has an at least partially elliptical cross section. 9. The temperature measuring device according to any one of claims 1 to 8, wherein the guide channel (52) is tapered in a funnel shape in a direction away from the housing (12). 10. The temperature measuring device according to any one of claims 1 to 9, wherein the strut (30) protrudes from the housing (12) more than the temperature probe (32).

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