Sensors and measuring devices equipped with sensors
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- ROBERT BOSCH GMBH
- Filing Date
- 2023-11-15
- Publication Date
- 2026-08-05
Smart Images
Figure 0007901258000001 
Figure 0007901258000002 
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Abstract
Description
Technical Field
[0001] Prior Art In the prior art, various sensors are known which are sensors combining a pressure sensor and a temperature sensor and which are configured as measurement sensors that can be inserted together with connecting pipe pieces into a measurement opening of a channel member containing a flow channel for the fluid medium to be measured. In order to be able to measure the temperature of the flowing medium as accurately and quickly as possible, it is advantageous to arrange the temperature measurement cell as close as possible to the end face of the measurement sensor within the region where it is inserted into the medium. In this case, especially when the medium is a gas, it is desirable that the thermal mass of the temperature probe is as small as possible.
[0002] For measuring the pressure in a corrosive medium, there are pressure sensors with so-called oil reservoirs which ensure the separation of the measurement medium from the actual pressure measurement cell via a separation membrane. The size of the membrane has a great influence on the achievable accuracy of the sensor. The larger the membrane, the more accurate the pressure signal. Such sensors are known, for example, from German Patent Application Publication No. 102008054382.
[0003] From German Patent Application Publication No. 102012204950, a sensor combining a pressure measurement function and a temperature measurement function is known. In this known sensor, the temperature probe in the sleeve is guided so as to pass through the center of the separation membrane. At the same time, the separation membrane is moved in the direction of the center of the sensor housing. Therefore, the medium must be guided into the interior of the connecting pipe piece so as to pass through the supply opening of the connecting pipe piece. As a result, advantages such as, for example, the frost resistance of the sensor are restricted.
[0004] Disclosure of the Invention The present invention relates to a sensor for detecting the pressure and temperature of a fluid medium, the sensor comprising a sensor housing with a connecting tube piece for insertion into a measuring opening, a pressure sensor element disposed within the sensor housing, and a channel extending within the connecting tube piece and filled with a pressure-transmitting fluid, wherein the channel is closed on the side facing the fluid medium by a separation membrane and connected on the side opposite to the fluid medium to the pressure sensor element such that the pressure of the medium acting on the separation membrane can be transmitted to the pressure sensor element via the pressure-transmitting fluid, and the sensor comprises a temperature probe disposed within the sensor housing for insertion into the measuring opening. According to the present invention, the connecting tube piece has a first region in the longitudinal direction that is continuous with the sensor housing, a second region that is continuous with the first region, and a third region that is continuous with the second region, wherein the outer diameter of the second region is smaller than the outer diameters of the first region and the third region, thereby creating a free space between the first region and the third region, and the temperature probe is guided through the first region and into the free space.
[0005] Furthermore, the present invention relates to a measuring device comprising such a sensor and a channel member having a flow channel for a flowing fluid medium, wherein a measuring opening is formed in the channel member, and a connecting tube piece of the sensor is fitted into the measuring opening such that at least a third area of the connecting tube piece provided with a separation membrane and an end portion of the temperature probe provided with a temperature measuring cell are exposed to the flowing medium.
[0006] Advantages of the invention The sensor according to the present invention for detecting the pressure and temperature of a fluid medium advantageously allows for a significant improvement in the structural space required for a combination of a temperature sensor with an oil reservoir and a pressure sensor. Since the connecting tube piece, which is to be fitted into the measurement opening, can be extended into the fluid flow channel, advantageously, extending the connecting tube piece provides a region where unnecessary material of the connecting tube piece can be left free to obtain free space for a temperature probe with a temperature measuring cell to intervene. Therefore, in the solution according to the present invention, the temperature measuring cell of the temperature probe can be advantageously moved behind the oil reservoir, viewed from the end face of the connecting tube piece in the longitudinal direction of the connecting tube piece. Conversely, the separation membrane with the oil reservoir is positioned in front of the temperature measuring cell, viewed in the longitudinal direction. This eliminates the need to guide the temperature probe through the separation membrane, which could result in unfavorable reduction of the separation membrane, or the need to circumvent the temperature probe around the separation membrane within the same measurement opening in a cumbersome manner. Therefore, the diameter of the separation membrane provided in the third region of the connecting tube piece can be made larger, in which case the maximum diameter is advantageously limited substantially by the insertability of the connecting tube piece into the measurement opening, but no longer limited by the required space for the temperature probe.
[0007] Advantageous embodiments and variations of the present invention are made possible by the features contained in the dependent claims.
[0008] The free space can be easily formed in the form of a ring groove that encircles the second region, the ring groove being laterally formed by a particularly annular ring-shaped surface of the first region facing the free space and a particularly annular ring-shaped surface of the third region facing the free space. The third region, fixed to the second region, of a connecting tube piece such as a dish-shaped base or stamp, can thus be held in the flow of the medium.
[0009] The end portion of the temperature probe having the temperature-measuring cell can, advantageously, protrude into free space from the first portion of the connecting tube piece, particularly the annular ring-shaped surface facing free space. This allows the flowing medium to circulate sufficiently around the temperature-measuring cell of the temperature probe, even though the separation membrane is positioned in front of the temperature-measuring cell in the longitudinal direction.
[0010] In a favorable embodiment, it can be assumed that the end section is wound in free space, at least partially, around the second section of the connecting tube piece. This significantly improves the thermal isolation between the temperature measuring cell and the connecting tube piece.
[0011] The temperature probe may have a connection region located on the side opposite the end region, within the internal space of the sensor housing. The connection region can be easily brought into contact with a circuit support or contact element provided inside the internal space of the housing.
[0012] The separation membrane is preferably located at the end of the third section of the connecting tube piece that is opposite to the sensor housing, thereby being positioned on the end face of the connecting tube piece that is inserted into the measuring opening.
[0013] The temperature probe may have a substrate, for example, made of plastic, that extends in the longitudinal direction, and the substrate includes a connecting line that extends in the longitudinal direction. The connecting line may be incorporated into the plastic of the substrate, for example, by injection molding. The end region of the substrate with the temperature measuring cell can have a variety of shapes. In this case, there are advantageously many degrees of freedom, because the entire free space between the first region and the third region can be used for the geometric structure of the end region. The substrate can be sealed to a housing opening provided in the first region via a simple sealing element. This allows the temperature probe to be easily pushed into a housing opening provided in the first region of, for example, a connecting tube piece.
[0014] Furthermore, a measuring device is advantageous, comprising a sensor having the above-described features and a channel member having a flow channel for a flowing fluid medium, wherein a measuring opening is formed in the channel member, and the connecting tube piece of the sensor is fitted into the measuring opening such that at least a third area of the connecting tube piece, provided with a separation membrane, and an end area of the temperature probe, provided with a temperature measuring cell, are exposed to the flowing medium. The first area of the connecting tube piece is fitted into the measuring opening and does not need to protrude from the measuring opening. Therefore, advantageously, a sealing element for sealing the measuring opening can be placed in the first area.
[0015] In an advantageous embodiment, the measuring opening may have a recess that opens toward the flow channel. The recess may be formed, for example, in a conical shape. The end portion of the temperature probe, where the temperature measuring cell is located, can be positioned at least partially within the region of the measuring opening formed by the recess. This advantageously achieves, on the one hand, that the third portion of the connecting tube piece with the separation membrane does not need to be inserted very deeply into the flow channel, while on the other hand, that effective flow around the region of the temperature probe where the temperature measuring cell is located is still possible. Preferably, the shape of the connecting tube piece can be improved so that the flowing medium flows strongly into the region of the recess.
[0016] Possible embodiments of the present invention will be described below with reference to the accompanying drawings. [Brief explanation of the drawing]
[0017] [Figure 1] This is a cross-sectional view of a first embodiment of a measuring device equipped with a sensor according to the present invention. [Figure 2] This is a cross-sectional view of a second embodiment of a measuring device equipped with a sensor according to the present invention. [Figure 3] This is a cross-sectional view of a third embodiment of a measuring device equipped with a sensor according to the present invention. [Figure 4]This figure shows an example of one embodiment of a temperature probe.
[0018] Embodiments of the Invention Figure 1 shows a cross-sectional view of a first embodiment of a measuring device 100 equipped with a sensor 1 according to the present invention. The sensor 1 includes a sensor housing 10, which in this case consists of, for example, two parts: a lower housing 12 made of, for example, metal or plastic, and an upper housing 11 made of, for example, plastic. The upper housing 11 can be positioned on the lower housing 12 with a sealing element 51 interposed therebetween, and a closed internal housing space 8 is formed between the lower housing 12 and the upper housing 11, in which a pressure sensor 2, configured as, for example, a pressure measuring cell, is positioned. The pressure sensor 2 may be electrically contacted, for example, a printed circuit board 3, which in turn may be electrically connected to a connecting pin 52 of the upper housing 11 via a contact spring (not shown). However, the pressure sensor 2 may be in contact with the connecting pin 52 in other forms. The lower housing 12 has a connecting tube piece 5, which may be integrally formed with the lower housing 12 and is suitable for insertion into a measuring opening 112 of a channel member 110, as will be described later. The connecting tube piece 5 may have, for example, a cylindrical outer wall and may be, for example, preferably a cylindrical measuring opening 112. The outer wall of the connecting tube piece 5 may have an annular seal 50, such as an O-ring, in the first area 13 of the connecting tube piece to seal the measuring opening 112.
[0019] In the longitudinal extension direction L of the connecting tube piece 5, shown only in Figure 3, which extends parallel to the insertion direction of the connecting tube piece 5 within the measuring opening 112, the first region 13 is followed by a second region 14 and a third region 15. As can be seen in Figure 1, the outer diameter of the second region 14 is formed to be significantly smaller than the outer diameter of the first region 13. The outer diameter of the third region 15 can correspond to the outer diameter of the first region 13, and is therefore formed to be significantly larger than the outer diameter of the second region 14. Consequently, an annular ring groove is formed in the connecting tube piece 5, and this ring groove is formed by the annular ring-shaped surface 13a of the first region 13 and the annular ring-shaped surface 15a of the third region 15. This provides a free space 17 between the first region 13 and the third region 15.
[0020] As further shown in Figure 1, the connecting pipe piece 5 has a channel 40 filled with a pressure-transmitting fluid 4, which is closed at the end face of the third region 15 by a flexible separation membrane 16, for example, made of steel, and on the side opposite to the fluid medium, is connected to a pressure sensor element 2 so that the pressure of the medium 9 acting on the separation membrane 16 can be transmitted to the pressure sensor element 2 via the pressure-transmitting fluid 4. The channel 40 may have a first channel region 42 located in the first region 13 of the connecting pipe piece 5, a second channel region 43 located in the second region 14 of the connecting pipe piece 5, and a third channel region 44 located in the third region 15 of the connecting pipe piece 5. The diameter of the second channel region 43 may be smaller than the diameters of the first channel region 42 and the third channel region 44. This is not necessarily required, but it would be beneficial to reduce the outer diameter of the second region 14 of the connecting pipe piece 5. The channel 40 can be filled with pressure-transmitting fluid 4 via a side channel 41, as shown in Figure 1. This side channel 41 is provided, for example, in the first area 13 and can be closed using a plug or by other means.
[0021] Sensor 1 further includes a temperature probe 6. The temperature probe 6 is guided to start from the internal space 8 of the housing in the longitudinal direction, penetrate a first region 13, and enter the free space 17. An end region 66 of the temperature probe 6, which has a temperature measuring cell 63 (not shown in Figure 1), starts from the surface 13a of the first region 13 of the connecting tube piece 5 facing the free space 17 and protrudes into the free space 17. The connection region of the temperature probe on the side opposite to the end region 66 may be located in the internal space 8 of the sensor housing 10, and may be electrically contacted, for example, with a printed circuit board 3 in the internal space 8 of the housing.
[0022] Figure 2 shows one evolved form of the sensor 1 according to the present invention. The sensor 1 in Figure 2 differs from the embodiment in Figure 1 only in that the end region 66, which has a temperature measuring cell 63, is wound at least partially around the second region 14 within the free space 17 (winding portion 67), and more specifically, preferably so as not to contact the outer circumferential surface of the second region 14. The entire contour of the end region 66 is contained within the range obtained by projecting the third region 15 onto the first region 13 in the longitudinal direction, and therefore no part of the end region 66 protrudes beyond the free space 17. This is beneficial in that the connecting tube piece 5 can be pushed into the measuring opening 112 without issue. With the configuration of the end region 66 with the winding portion 67 shown in Figure 2, it is advantageous that the temperature measuring cell 63 is held in the flow via a very long exposed portion of the temperature probe 66 that is located in the free space. Therefore, the original temperature measuring cell 63 of the temperature probe 6 is thermally better separated from the first region 13 of the connecting tube piece 5 than in the embodiment shown in Figure 1.
[0023] Figures 1 and 2 further show a measuring device 100, which, in addition to the sensor 1 described above, has a channel member 110. The channel member 110 may have, for example, a cylindrical wall surrounding a flow channel 111, in which, for example, a cylindrical measuring opening 112 is located, which opens into the flow channel. The fluid medium 9 (gas or liquid) whose pressure and temperature are to be detected flows through the flow channel 111 during operation. In Figures 1 and 2, the connecting tube piece 5 of the sensor 1 is fitted into the measuring opening 112 such that at least a third region 15 of the connecting tube piece 5, where the separation membrane 16 is provided, and an end region 66 of the temperature probe 6, where the temperature measuring cell 63 is provided, are exposed to the flowing medium 9. The measuring opening 112 is sealed in the first region 13 via an O-ring configured as a seal ring 50. To fix the sensor 1, a ring-shaped retaining metal sheet 30 formed as a deep-drawn member can be used, and this retaining metal sheet 30 is attached to the outer circumferential surface of the channel member 110. By using a disc spring 31 that is supported on one end by the retaining metal sheet 30 and on the other end by a snap ring 32 fitted over the lower part of the housing 12, the connecting tube piece 5 is made movable into the measuring opening 12 against the spring force of the disc spring 31 in the longitudinal extension direction L. This means is useful for freeze protection.
[0024] FIG. 3 shows an advantageous variant of the measuring device 100 and the sensor 1. In this embodiment, the measuring opening 112 has a recess 113 that opens towards the flow channel 111. The recess 113 may be formed, for example, in a conical shape as shown in the figure. The end region 66 provided with the temperature measuring cell 63, which includes the winding portion 67, of the temperature probe 6 is at least partially disposed inside the region formed by the recess 113 of the measuring opening 112. Nevertheless, the temperature measuring cell 63 is directly exposed to the flow of the medium 9 as shown in FIG. 2. Thereby, the first region 13 of the connecting pipe piece 5 can be formed shorter compared to FIGS. 1 and 2, and it can be seen that the third region 15 of the connecting pipe piece 5 provided with the separation membrane 16 does not need to be inserted as deeply into the flow channel 111 as in FIGS. 1 and 2. Thereby, the required space in the longitudinal extension direction L required for arranging the sensor 1 is reduced.
[0025] FIG. 4 shows an embodiment of the temperature probe 6. The temperature probe 6 can have a substrate 64, for example made of plastic, that extends, for example, in the longitudinal extension direction L, and the substrate 64 includes a connecting line 61 that extends in the longitudinal extension direction L. The connecting line 61 may be incorporated into the substrate 64 by injection molding and can have a connecting region 62 that protrudes from the substrate 64 in the first end region of the substrate 64. The end of the connecting line 61 on the side opposite to the connecting region 62 is connected to the temperature measuring cell 63, and this temperature measuring cell 63 is surrounded by the second end region 66 of the substrate 64. The substrate 64 may be sealed against the receiving opening 69 provided in the first region 13 of the connecting pipe piece 5 via a sealing element 53, for example an O-ring, sandwiched in the groove 65. Such a temperature probe 6 can be used, for example, in the sensor 1 shown in FIG. 1.
Claims
1. A sensor (1) for detecting the pressure and temperature of a fluid medium (9), A sensor housing (10) is provided with a connecting tube piece (5) for insertion into the measuring opening (112), A pressure sensor element (2) is disposed within the sensor housing (10), The connecting tube piece (5) includes a channel (40) filled with a pressure-transmitting fluid (4), The channel (40) is closed on the side facing the fluid medium (9) by a separation membrane (16), and on the side opposite to the fluid medium (9), it is connected to the pressure sensor element (2) so that the pressure of the fluid medium (9) acting on the separation membrane (16) can be transmitted to the pressure sensor element (2) via the pressure transmission liquid (4). The sensor (1) includes a temperature probe (6) positioned in the sensor housing (10) for insertion into the measuring opening (112). In my case (1), The connecting tube piece (5) has, in the longitudinal direction (L), a first region (13) that continues to the sensor housing (10), a second region (14) that continues to the first region (13), and a third region (15) that continues to the second region (14). The outer diameter of the second region (14) is smaller than the outer diameter of the first region (13) and the outer diameter of the third region (15), thereby creating a free space (17) between the first region (13) and the third region (15). The temperature probe (6) is guided through the first area (13) and enters the free space (17). A sensor (1) characterized by the following features.
2. The free space (17) is formed by a ring groove that surrounds the second area (14) in an annular manner. The aforementioned ring groove is Of the first area (13), the surface (13a) facing the free space (17), and of the third area (15), the surface (15a) facing the free space (17) The sides are formed by The sensor (1) according to claim 1.
3. The end portion (66) of the temperature probe (6) having the temperature measuring cell (63) protrudes into the free space (17) from the surface (13a) of the first portion (13) of the connecting tube piece (5) that faces the free space (17). The sensor (1) according to claim 1 or 2.
4. The end region (66) is at least partially wrapped around the second region (14) within the free space (17). The sensor (1) according to claim 3.
5. The temperature probe (6) has a connection region (62) located on the side opposite to the end region (66) and positioned within the internal space (8) of the sensor housing (10). The sensor (1) according to claim 3.
6. The separation membrane (16) is positioned at the end of the third region (15) of the connecting tube piece (5) that is on the side opposite to the sensor housing (10). The sensor (1) according to claim 1 or 2.
7. The temperature probe (6) has a base (64) that extends in the longitudinal direction (L), The base body (64) is provided with a connecting line (61) extending in the longitudinal direction (L), The base (64) is sealed to the receiving opening (69) provided in the first area (13) via the sealing element (53). The sensor (1) according to claim 1 or 2.
8. Measuring device (100), The measuring device (100) comprises a sensor (1) according to claim 1 or 2 and a channel member (110) having a flow channel (111) for a flowing fluid medium (9), A measuring opening (112) is formed in the channel member (110), The connecting tube piece (5) of the sensor (1) is fitted into the measuring opening such that at least the third region (15) of the connecting tube piece (5) where the separation membrane (16) is provided, and the end region (66) of the temperature probe (6) where the temperature measuring cell (63) is provided, are exposed to the flowing fluid medium (9). Measuring device (100).
9. The measuring opening (112) has a recess (113) that opens toward the flow channel (111), Of the temperature probe (6), the end region (66) on which the temperature measuring cell (63) is provided is at least partially located inside the region formed by the recess (113) of the measuring opening (112). The measuring device (100) according to claim 8.