DETECTION DEVICE FOR A PHYSICAL QUANTITY

Abstract

Detection device (20) for a physical quantity, comprising: a housing (100) which is inserted from one side of a distal end through an insertion hole of a main passage (22) through which a target gas flows and is arranged in the main passage (22); a cover (200) which, in conjunction with the housing (100), forms a lower passage (134, B) which draws in a portion of the target gas flowing through the main passage (22); a carrier body which is received in the housing (100); and a sensor element (311) which is carried by the carrier body and arranged in the underpass (134, B), wherein the housing (100) has: a first adhesive groove (160A) comprising a groove section (161) of a proximal end extending along a proximal end of the housing (100), and a pair of groove sections (162, 163) extending from the groove section (161) of the proximal end to a side of a distal end of the housing (100) with respect to a measuring unit (113) of the sensor element (311), wherein a first adhesive (401) is applied to the first adhesive groove (160A); and a second adhesive groove (160B) extending along the underpass (134, B) and onto which a second adhesive (402) is applied, and the first adhesive (401) has a Young's modulus that is higher than that of the second adhesive (402), and the second adhesive (402) has a thixotropy that is higher than that of the first adhesive (401).

Description

Technical field

[0001] The present invention relates to a detection device for a physical quantity, which, for example, detects a physical quantity of the intake air of an internal combustion engine. State of the art

[0002] PTL 1 discloses a structure of a flow rate measuring device comprising: a base, a plate connected to the base by a surface along a flow direction of air, which is a fluid to be measured, a flow rate detection element provided so that it is exposed to the plate and detects a flow rate of the air, a circuit board attached to a surface of the plate on the same side as the flow rate detection element and comprising a control circuit that processes a signal from the flow rate detection element, and a cover attached to the plate and the base.

[0003] According to PTL 1, the cover is attached to the plate and the base using a thermosetting silicone adhesive. An inner wall surface of the flange and an outer circumferential wall surface of the cover, facing the inner wall surface, are bonded together using an epoxy adhesive. Technical problem

[0004] For example, in a detection device for a physical quantity that detects the flow rate of intake air drawn into an internal combustion engine, a device body is arranged in an intake passage. The device body preferably has a small thickness to reduce pressure loss in the intake passage. However, with decreasing thickness, the stiffness of the main body section decreases, and there is a possibility that the detection accuracy will be affected. To improve the stiffness of the main body section, an epoxy adhesive is known to be used. However, since the epoxy adhesive has a low viscosity, it is difficult to maintain a tight seal.

[0005] In the flow rate measuring device described in PTL 1, an inner wall surface of a flange and an outer circumferential wall surface of a cover facing the inner wall surface are bonded together using an epoxy adhesive. Therefore, the reduction in the cross-sectional coefficient at the bonded section increases, the stiffness decreases, deformation during vibration increases, and stress can concentrate on the root of the base body.

[0006] WO 2015 / 198808 A1 describes a detection device in which parts are bonded with adhesives of different moduli of elasticity. Summary of the invention

[0007] The invention was made with regard to the above points and its object is to provide a detection device for a physical quantity that is capable of achieving both an improvement in stiffness and an improvement in sealing performance. Solution to the task

[0008] A detection device for a physical quantity of the invention, which solves the above-mentioned problem, comprises: a housing arranged so that it projects into a main passage through which a target gas flows; a cover forming a sub-passage in conjunction with the housing; a support body received in the housing; and a sensor element carried by the support body and arranged in the sub-passage.The housing comprises: a first adhesive groove, which is a groove filled with an adhesive for attaching the cover, extending along a proximal end of the housing and along the protrusion direction of the housing from the proximal end of the housing to a position on one side of a distal end of the housing relative to the carrier body, and is filled with a first adhesive; and a second adhesive groove extending along the undercut and filled with a second adhesive. The first adhesive has a Young's modulus higher than that of the second adhesive, and the second adhesive has a thixotropy higher than that of the first adhesive. Advantageous effects of the invention

[0009] According to the invention, it is possible to obtain a detection device for a physical quantity that is capable of improving both stiffness and sealing performance. Further features of the invention will become clear from the description and the accompanying drawings. In addition, the following embodiments will explain the tasks, configurations, and effects beyond those described above. Brief description of the drawings Fig. Figure 1 is a system representation illustrating an embodiment in which a detection device for a physical quantity according to the invention is used in a control system of an internal combustion engine. Fig. 2A is a front view of the detection device for a physical quantity. Fig. 2B is a rear view of the detection device for a physical quantity. Fig. 2C is a representation that points in one direction from arrow IIC into Fig. 2A is considered. Fig. 2D is a representation that is in one direction of arrow IID in Fig. 2A is considered. Fig. 2E is a top view of the detection device for a physical quantity. Fig. 2F is a view of the detection device for a physical quantity from below. Fig. 2G is a cross-sectional view that runs along line IIG-IIG in Fig. 2A is taken from. Fig. 2H is a cross-sectional view that follows line IIH-IIH in Fig. 2A is taken from. Fig. Figure 3 is a front view of a case. Fig. Figure 4 is a rear view of a cover. Fig. Figure 5 is a front view of a chip package. Fig. Figure 6 is a cross-sectional view taken along line VI-VI of Fig. 5 is taken from. Fig. Figure 7 is a cross-sectional view of the measuring unit of the detection device for a physical quantity taken along line VII-VII in the direction of an arrow pointing in Fig. 2H is shown. Fig. 8 is an enlarged view showing a main part VIII of the in Fig. 7 illustrated design. Fig. Figure 9 is a cross-sectional view taken along line IX-IX of Fig. 7 is taken from. Fig. Figure 10 is a cross-sectional view taken along line XX of Fig. 7 is taken from. Fig. Figure 11 is a representation to discuss a modification of the first embodiment. Description of embodiments

[0010] One mode for carrying out the invention described below (embodiment) solves various problems, as is desirable for an actual product, and it solves various problems, as is desirable for the use of a detection device, which in particular detects a physical quantity of the intake air of a vehicle and has various effects. One of the various problems solved by the following embodiments corresponds to the content described above in the section on the problem solved by the invention, and one of the effects achieved by the following embodiments is the effect described in the section on the effect of the invention. The various problems solved by the following embodiments and the various effects achieved by the following embodiments are described in the following description of the embodiments.Therefore, the problems and effects solved by the examples described in the following examples are also described in the content that is not the content in the section on the problem solved by the invention and the section on the effect of the invention.

[0011] In the following embodiments, the same reference numerals denote the same configuration, even if the figure numbers are different, and the same functions and effects are achieved. For the embodiment already described, only reference numerals are given to the drawings, and their descriptions are omitted.

[0012] Fig. Figure 1 is a system diagram illustrating an embodiment in which a detection device for a physical quantity according to the invention is used in a control system 1 of an internal combustion engine of the type with electronic fuel injection. Based on the operation of an internal combustion engine 10, which has an engine cylinder 11 and an engine piston 12, intake air from an air cleaner 21 is drawn in as the target gas 2 and directed into a combustion chamber of the engine cylinder 11 through an intake manifold comprising a main passage 22, a throttle body 23, and an intake manifold 24.The physical quantity of the target gas 2, which is the intake air supplied to the combustion chamber, is detected by the detection device 20 for a physical quantity according to the invention. Fuel is supplied by the fuel injector 14 based on the detected physical quantity and is directed into the combustion chamber in a state of an air-fuel mixture together with the target gas 2. In this embodiment, the fuel injector 14 is furthermore provided with an intake port of the internal combustion engine. The fuel injected into the intake port forms an air-fuel mixture together with the target gas 2, which is directed into the combustion chamber via the intake valve 15 and combusted to generate mechanical energy.

[0013] The fuel and air entering the combustion chamber are in a mixed state. This air-fuel mixture is explosively ignited by a spark plug 13 to generate mechanical energy. After the explosion, the gas is directed by an exhaust valve 16 to an exhaust pipe and released from the vehicle as exhaust gas 3. The flow rate of the target gas 2, which is the intake air, entering the combustion chamber is controlled by a throttle valve 25, the opening of which is changed based on the operation of the accelerator pedal. The fuel supply quantity is controlled based on the flow rate of the intake air entering the combustion chamber.

[0014] An operator controls the flow rate of the intake air that is directed into the combustion chamber by controlling the opening of the throttle valve 25, so that the mechanical energy generated by the internal combustion engine can be controlled.

[0015] Physical quantities, such as flow rate, temperature, humidity, and pressure of the target gas 2, which is the intake air drawn in by the air purifier 21 and flowing through the main passage 22, are detected by a physical quantity detection device 20. An electrical signal representing the physical quantity of the intake air is input from the physical quantity detection device 20 to a control device 4. Additionally, the output of a throttle angle sensor 26, which measures the opening of the throttle valve 25, is input to the control device 4. Furthermore, the output of a rotation angle sensor 17 is input to the control device 4 to measure the positions and states of the engine piston 12 of the internal combustion engine, the intake valve 15, and the exhaust valve 16, as well as the rotational speed of the internal combustion engine.The output of an oxygen sensor 28 is entered into the control device 4 to measure the state of a mixture ratio between the amount of fuel and the amount of air in the exhaust gas 3.

[0016] The control device 4 calculates the fuel injection quantity and the ignition timing based on the physical quantity of the intake air, which is output by the detection device 20, and the rotational speed of the internal combustion engine, which is measured based on the output of the rotational angle sensor 17. Based on these calculation results, the amount of fuel supplied by the fuel injector 14 and the ignition timing of the spark plug 13 are controlled. The fuel injection quantity and the ignition timing are, in fact, finely controlled based on changes in temperature and throttle angle, which are detected by the detection device 20, changes in engine speed, and the state measured by the oxygen sensor 28.The control device 4 controls an amount of air that bypasses the throttle valve 25 using an idle air control valve 27 in an idle operating condition of the internal combustion engine, and it controls the speed of the internal combustion engine in the idle operating condition.

[0017] The fuel supply quantity and ignition timing, which are the main control variables of the internal combustion engine, are both calculated using the output of the detection device 20 for a physical quantity as the main parameter. Therefore, improving the detection accuracy of the detection device 20 for a physical quantity, suppressing time-dependent changes, and improving reliability are important to enhance control accuracy and ensure vehicle reliability.

[0018] Especially in recent years, the demand for fuel savings in vehicles and the desire for exhaust gas purification have increased dramatically. To meet these demands, it is crucial to improve the detection accuracy of the physical quantity of the intake air detected by the detection device 20. It is also important that the detection device 20 maintains its reliability.

[0019] The vehicle on which the physical quantity detection device 20 is mounted is used in an environment with significant changes in temperature and humidity. It is desirable that the physical quantity detection device 20 be able to detect a response to changes in temperature or humidity in the operating environment, as well as a response to dust, pollutants, and the like.

[0020] The detection device 20 for a physical quantity is mounted on an intake manifold exposed to heat generated by an internal combustion engine. Therefore, the heat generated by the internal combustion engine is transferred to the detection device 20 via the intake manifold. Since the detection device 20 detects the flow rate of the target gas by exchanging heat with it, it is important to minimize the influence of external heat as much as possible.

[0021] As described below, the detection device 20 for a physical quantity, which is mounted on the vehicle, not only solves the problem described in the section on the problem solved by the invention and not only performs the effect described in the section on the effect of the invention, but also solves various problems required for a product, taking sufficient account of the various problems described above, and performs various effects. Specific problems to be solved and effects to be achieved by the detection device 20 for a physical quantity are described in the following description of embodiments. <Erste Ausführungsform>

[0022] Fig. Figures 2A to 2F are illustrations depicting the appearance of the detection device for a physical quantity. In the following description, it is assumed that the target gas flows along the central axis of the main passage.

[0023] The detection device 20 for a physical quantity is used in a state in which it is inserted into the main passage 22 through a mounting hole provided in a passage wall of the main passage 22 and is attached to the main passage 22. The detection device 20 for a physical quantity has a housing that is arranged in the main passage 22 through which the target gas flows. The housing of the detection device 20 for a physical quantity comprises a casing 100 and a cover 200 that is attached to the casing 100.

[0024] For example, housing 100 is formed by injection molding a synthetic resin material. Examples of cover 200 include a plate-like element made of a metal material and a plate-like element made of a synthetic resin material.

[0025] The housing 100 has a flange 111 for attaching the detection device 20 for a physical quantity to the intake body, which is the main passage 22, a connector 112 which projects from the flange 111 and is exposed to the outside from the intake body for electrical connection with an external device, and a measuring unit 113 which extends from the flange 111 so that it projects towards the center of the main passage 22.

[0026] The measuring unit 113 has a thin and elongated shape extending straight from the flange 111, and it has a wide front surface 121, a rear surface 122, and a pair of narrow side surfaces 123 and 124. The measuring unit 113 is arranged so that it projects from the inner wall of the main passage 22 towards the center of the main passage 22 in a state in which the detection device 20 for a physical quantity is attached to the main passage 22. Furthermore, the front surface 121 and the rear surface 122 are arranged parallel to each other along the central axis of the main passage 22.Beneath the narrow side surfaces 123 and 124 of the measuring unit 113, side surface 123 is arranged on one side in the longitudinal direction of the measuring unit 113, so that it faces the upstream side of the main passage 22, and side surface 124 is arranged on the other side in the lateral direction of the measuring unit 113, so that it faces the downstream side of the main passage 22. In a state in which the detection device 20 for a physical quantity is attached to the main passage 22, the section of the distal end of the measuring unit 113 is defined as the lower surface 125.

[0027] In the measuring unit 113, a lower inlet 131 is provided on the side surface 123, and a first outlet 132 and a second outlet 133 are provided on the side surface 124. The lower inlet 131, the first outlet 132, and the second outlet 133 are located on the section of the distal end of the measuring unit 113 that extends from the flange 111 in the direction of the center of the main passage 22. Therefore, gas can be drawn into the lower inlet in the section near the center, away from the inner wall surface of the main passage 22. Thus, the detection device 20 can measure the gas flow rate in the section away from the inner wall surface of the main passage 22 and can compensate for a decrease in measurement accuracy due to the influence of heat or the like.

[0028] The detection device 20 for a physical quantity has a shape in which the measuring unit 113 extends longitudinally along the axis from the outer wall of the main passage 22 towards the center, while the widths of the side surfaces 123 and 124 are narrow, as shown in Fig. 2B and Fig. 2D representation. Consequently, the detection device 20 can suppress the fluid resistance to a small value relative to the target gas 2 for a physical quantity.

[0029] The measuring unit 113 of the detection device 20 for a physical quantity is inserted into the interior through a mounting hole provided in the main passage 22, and the flange 111 of the detection device 20 for a physical quantity rests against the main passage 22 and is fastened to the main passage 22 with a screw. The flange 111 has a substantially rectangular shape in a top view with a predetermined plate thickness and, as shown in Fig. 2E and Fig. As illustrated in Figure 2F, mounting hole sections 141 are provided in pairs at diagonal corners. The mounting hole section 141 has a through hole 142 that penetrates the flange 111.

[0030] The flange 111 is attached to the main passage 22 by inserting a fastening screw (not shown) into the through hole 142 of the fastening hole section 141 and screwing the fastening screw into a screw hole of the main passage 22.

[0031] As in Fig. As illustrated in Figure 2E, four external ports 147 and one correction port 148 are provided inside the connector 112. The external port 147 is a port for outputting a physical quantity, such as a flow rate or temperature, which is a measurement result of the detection device 20 for a physical quantity, and a power source port for supplying direct current to operate the detection device 20 for a physical quantity. The correction port 148 is a port used to measure the manufactured detection device 20 for a physical quantity, to obtain the correction value with respect to each detection device 20 for a physical quantity, and to store the correction value in the memory inside the detection device 20 for a physical quantity.In the subsequent measurement operation of the detection device 20 for a physical quantity, the correction data representing the correction value stored in the memory are used and the correction port 148 is not used.

[0032] Fig. 2G is a cross-sectional view that runs along line IIG-IIG in Fig. 2A is taken from Fig. 2H is a cross-sectional view that follows line IIH-IIH in Fig. 2A is taken from Fig. Figure 3 is a front view of the housing and illustrates a state in which the cover is removed. Fig. 4 is a rear view of the cover, Fig. Figure 5 is a front view of the chip package and Fig. Figure 6 is a cross-sectional view taken along line VI-VI in Fig. 5. It should be noted that in the following description, the longitudinal direction of the measuring unit 113, which is a direction in which the measuring unit 113 extends from the flange 111, can be referred to as the Z-axis, the lateral direction of the measuring unit 113, which is a direction extending from the underpass inlet 131 of the measuring unit 113 towards the first outlet 132, can be referred to as the X-axis, and the thickness direction of the measuring unit 113, which is a direction from the front surface 121 towards the rear surface 122 of the measuring unit 113, can be referred to as the Y-axis.

[0033] The housing 100 is provided with an underpass slot 150 to form the underpass 134 and a circuit chamber 135 to connect a connection terminal of the chip package 310 to the external terminal 147. As shown in Fig. As illustrated in Figure 3, the circuit chamber 135 and the lower passage groove 150 are recessed in front of the measuring unit 113. The circuit chamber 135 is located in a region on one side (side of the side surface 123) in the X-axis direction, which is the upstream side position in the flow direction of the target gas 2 in the main passage 22. The main passage groove 150 is located above a region on the side of the distal end in the Z-axis direction (side of the lower surface 125) of the measuring unit 113 with respect to the circuit chamber 135, and a region on the other side in the X-axis direction (side of the side surface 124), which is the downstream side position in the flow direction of the target gas 2 in the main passage 22 with respect to the circuit chamber 135.

[0034] The underpass groove 150 is covered by the cover 200 to form the underpass 134. The underpass groove 150 has a first underpass groove 151 and a second underpass groove 152 branching off in the middle of the first underpass groove 151. The first underpass groove 151 is formed so that it extends along the X-axis direction of the measuring unit 113 between the underpass inlet 131, which opens to the side surface 123 on one side of the measuring unit 113, and the first outlet 132, which opens to the side surface 124 on the other side of the measuring unit 113. The first underpass groove 151, in conjunction with the cover 200, forms a first underpass A, which draws in the target gas 2 flowing in the main passage 22 from the underpass inlet 131 and returns the drawn-in target gas 2 from the first outlet 132 to the main passage 22.The first subpass A has a flow path that extends from the subpass inlet 131 along the flow direction of the target gas 2 in the main passage 22 and is connected to the first outlet 132.

[0035] The second underpass groove 152 branches off at an intermediate position of the first underpass groove 151 and is bent towards the side of the proximal end (flange side) of the measuring unit 113, extending along the Z-axis direction of the measuring unit 113. Subsequently, the section of the proximal end of the measuring unit 113 is bent towards the other side (side of the side surface 124) in the X-axis direction of the measuring unit 113, turns around towards the section of the distal end of the measuring unit 113, and again extends along the Z-axis direction of the measuring unit 113. The first outlet 132 is bent towards the other side (side of the side surface 124) in the X-axis direction of the measuring unit 113 and is positioned upstream of the first outlet so that it is continuous with the second outlet 133 and opens towards the side surface 124 of the measuring unit 113.The second outlet 133 is arranged so that it faces the main passage 22 towards the downstream side in the flow direction of the target gas 2. The second outlet 133 has an opening area that is essentially the same as or slightly larger than that of the first outlet 132, and it is located adjacent to the measuring unit 113 on the side of the proximal end along the longitudinal axis of the first outlet 132.

[0036] The second underpass groove 152, in conjunction with the cover 200, forms a second underpass B through which the incoming measurement target gas 2, branched off from the first underpass A, flows and is returned from the second outlet 133 to the main passage 22. The second underpass B has a flow path that runs upwards and downwards along the Z-axis direction of the measuring unit 113.This means that the second subpass B has a feed-through passage section B1, which branches off in the middle of the first subpass A and extends towards the side of the proximal end of the measuring unit 113 (direction away from the first subpass A), and a return passage section B2, which is bent back and routed around the side of the proximal end of the measuring unit 113 (end section of the separation passage section) and extends towards the side of the distal end of the measuring unit 113 (direction approaching the first subpass A). The return passage section B2 is connected to the second outlet 133, which opens towards the downstream side in the flow direction of the target gas 2 at a position on the downstream side in the flow direction of the target gas 2 in the main passage 22 towards the subpass inlet 131.

[0037] In the second passage section B, a flow rate sensor (a flow rate detection unit) 311 is arranged at an intermediate position of the incoming passage section B1. Since the second sub-passage B is formed so that it extends along the longitudinal direction of the measuring unit 113 and runs both upwards and downwards, the passage length can be ensured to a greater extent and the influence on the flow rate sensor 311 can be reduced if a pulsation occurs in the main passage.

[0038] The flow rate sensor 311 is provided in a chip package 310. As in Fig. As illustrated in Figure 6, the chip package has a configuration in which the flow rate sensor 311 and the LSI are mounted on the conductor frame 312, and the entire chip package is formed with resin. As shown in Fig. 2H and Fig. As illustrated in Figure 3, the chip package 310 has a section of a proximal end that is attached to the circuit chamber 135 and a section of a distal end that is arranged so that it protrudes into the second underpass groove 152, and the flow rate sensor 311 is provided on the section of the distal end.

[0039] The flow rate sensor 311 is supported by the chip package 310, so that it is exposed to the inlet passage section B1 of the second subpass B. The chip package 310 forms a support body that carries the flow rate sensor 311. The flow rate sensor 311 is positioned so that it faces a groove bottom surface 152a of the second subpass groove 152 at a predetermined distance, and it measures the flow rate of the target gas flowing through the second subpass B. As shown in Fig. 3 and Fig. As illustrated in Figure 5, the chip package 310 is provided with several external conductors 313 at the section of the proximal end and is connected to the external terminal 147 by laser welding in the circuit chamber 135. The external conductor 313 is formed by a portion of the conductor frame 312 projecting from the package body of the chip package 310.

[0040] The housing 100 is equipped with a neutralization plate 340 for neutralizing the target gas flowing through the second lower passage B. As in Fig. As illustrated in Figure 2H, the neutralization plate 340 is positioned so that it projects towards the second underpass groove 152, forming part of the groove bottom surface 152a of the second underpass groove 152. As shown in Fig. As illustrated in Figure 3, the neutralization plate 340 is positioned such that it extends from a position on the side of the first subpass A, located on the upstream side of the chip package 310 in the flow direction of the target gas, through the inlet passage section B1 of the second subpass B, to a position on the side of the second outlet 133, located on the downstream side of the chip package 310 in the flow direction of the target gas, facing the flow rate sensor 311 of the chip package 310. The neutralization plate 340 is electrically connected to the external port 147 and neutralizes the target gas flowing through the second subpass B. Therefore, it is possible to prevent foreign particles contained in the target gas from adhering to the chip package 310 or the flow rate sensor 311 due to charge.

[0041] The housing 100 is provided with a ventilation passage 170, which is capable of directing the target gas from the second sub-passage B into the circuit chamber 135. As in Fig. As illustrated in Figure 7, the ventilation passage 170 has a configuration in which one end is open in the middle of the passage of the second sub-passage B, the other end is open to the circuit chamber 135, and the pressure of the target gas can be controlled from the second sub-passage B into the circuit chamber 135. The ventilation passage 170 is recessed in a groove in the measuring unit 113 and is configured in conjunction with the cover 200. The ventilation passage 170 has an inlet opening 171, which opens at a position offset from the passage wall surface of the second sub-passage B, a linear section 172, which has the shape of a slide and extends linearly from the inlet opening 171, and a curved section 173, which has the shape of a labyrinth and is connected to the circuit chamber 135 while being continuously curved several times with the linear section 172.

[0042] The cover 200 has a flat plate shape which covers the circuit chamber 135 and the underpass groove 150 of the measuring unit 113, and is attached to the front surface 121 of the housing 100. As shown in Fig. As illustrated in Figure 4, the cover 200 is provided with ribs 211 to 217 on the rear surface 201. The ribs 211 to 217 are formed along a section attached to the measuring unit 113 of the housing 100.

[0043] Fig. Figure 7 is a cross-sectional view of the measuring unit of the detection device for a physical quantity taken along line VII-VII in the direction of an arrow pointing in Fig. 2H is marked, Fig. 8 is an enlarged view showing a main part VIII of the design in Fig. 7 illustrates, Fig. Figure 9 is a cross-sectional view taken along line IX-IX in Fig. 7 is taken from, and Fig. Figure 10 is a cross-sectional view along line XX in Fig. 7 is taken from.

[0044] The adhesive groove 160, into which an adhesive for attaching the cover 200 is applied, is formed in the measuring unit 113 of the housing 100. The adhesive groove 160 is formed on the front surface of the measuring unit 113 and along a section attached to the cover 200, and the ribs 211 to 217 of the cover 200 are inserted and attached to the cover 200 with an adhesive in the groove.

[0045] As in Fig. 7 and Fig. As illustrated in Figure 3, the adhesive groove 160 has a first adhesive groove 160A, onto which a first adhesive 401 is applied, and a second adhesive groove 160B, onto which a second adhesive 402 is applied. The first adhesive groove 160A is configured to extend along the proximal end of the housing 100 and to extend from the proximal end of the housing 100 to a position on the side of the distal end of the housing 100 with respect to the chip package 310 along the protruding direction of the housing 100, so that the first adhesive 401 can be applied. The second adhesive groove 160B extends along the underpass 134.

[0046] The first adhesive groove 160A has a groove section 161 extending in the X-axis direction along the base end of the housing 100, and groove sections 162 to 164 extending in the Z-axis direction from the groove section 161. The second adhesive groove 160B has groove sections 165 to 167 extending in the X-axis and Y-axis directions along the underpass grooves 151 and 152, which form the underpass 134.

[0047] As in Fig. As illustrated in Figure 7, the groove section 161 of the first adhesive groove 160A is provided such that it extends linearly between the side surface 123 on one side in the X-axis direction and the side surface 124 on the other side in the X-axis direction at the root section, which is the base end of the measuring unit 113. The groove section 162 is provided such that it extends linearly to a position closer to the side of the distal end of the housing 100 than the chip package 310, along the side surface 123, which is the outer edge of the measuring unit 113 of the housing 100. Similarly, the groove section 163 is provided such that it extends linearly to a position closer to the side of the distal end of the housing 100 than the chip package 310, along the side surface 124, which is the other outer edge of the measuring unit 113 of the housing 100.The groove sections 162 and 163 extend to a position DD on the side of the distal end of the chip package 310. The groove section 164 extends in the X-axis direction from the intermediate position of the groove section 161 towards the side of the distal end of the housing 100. It should be noted that the groove section 161 in the claims corresponds to a groove section of a proximal end, the groove sections 162 and 163 in the claims correspond to a pair of groove sections of an outer edge, and the groove section 164 in the claims corresponds to an intermediate groove section.

[0048] As in Fig. 9 and Fig. As illustrated in Figure 10, the groove sections 161 to 164 of the first adhesive groove 160A have a depth and a groove width such that they can be received in a state in which the ribs 211 to 214 of the cover 200 are inserted and the first adhesive 401 is placed between them.

[0049] As in Fig. As illustrated in Figure 8, the groove sections 161, 162, and 163 have a constant groove width N, and the groove section 164 has a groove width 2N, which is twice the groove width N of the groove sections 161, 162, and 163. In this embodiment, since the groove width of the groove section 164 is fixed at twice the groove width of the groove sections 161, 162, and 163, if, for example, the first adhesive 401 is applied in the direction indicated by the arrow in Figure 8, the groove width N of the groove section 164 can be reduced by 2N. Fig. As indicated in Figure 8, the first adhesive 401 is applied to the entire groove section 164 by moving it back and forth in the direction of the groove section 164. Therefore, the first adhesive 401 can be applied continuously to the groove sections 161 to 164 in a single stroke, simplifying and shortening the application process. Although double the amount has been used as an example, the process can be carried out similarly with an even number of applications. In cases where space is limited, doubling the area is preferred.

[0050] The groove section 165 of the second adhesive groove 160B is designed to extend in the X-axis direction along the underpass 134 at the distal end of the housing 100. More precisely, the first underpass groove 151 extends between the side surface 123 on one side and the side surface 124 on the other side in the X-axis direction along the end section on the distal end of the housing from both sides in the groove width direction of the first underpass groove.

[0051] The groove section 166 is designed to extend in the Z-axis direction along the underpass 134 from the distal end towards the proximal end of the housing. More precisely, the first underpass groove 151 extends from the side surface 123 towards the side surface 124 along the end section on the side of the proximal end of the housing from both sides in the groove width direction of the first underpass groove, curves towards the proximal end of the housing 100 at the intermediate position, and extends from the feed-through section B1 of the second underpass B to the curved section that bends back to the return underpass B2 along the partition separating the second underpass groove 152 and the circuit chamber 135.

[0052] The groove section 167 extends from a section in which the first underpass groove 151 and the second underpass groove 152 branch off towards the side surface 124 on the opposite side in the X-axis direction, and it extends along the Z-axis direction towards the side of the proximal end of the housing. The groove section 167 has a section that extends in the X-axis direction along an end section on the side of the proximal end of the housing from both sides in the groove width direction of the first underpass groove 151, and a section that extends in the Y-axis direction along a partition of the second underpass groove 152 that separates the feed-through section B1 and the return-through section B2.

[0053] The first adhesive 401 is characterized in that it has a higher Young's modulus than the second adhesive 402, and the second adhesive 402 is characterized in that it has a higher thixotropy than the first adhesive 401. In this embodiment, an epoxy adhesive having a linear coefficient of thermal expansion lower than that of the housing 100 is used for the first adhesive 401, and a silicone adhesive is used for the second adhesive 402. The first adhesive 401 can improve the stiffness of the housing 100, and the second adhesive 402 can improve the adhesion of the cover 200.

[0054] In the detection device 20 described above for a physical quantity, the housing 100 and the cover 200 are bonded and attached to each other using two types of adhesive, the first adhesive 401 to improve stiffness and the second adhesive 402 to improve adhesion, and the area on which the respective adhesive is applied is provided separately according to the application, thereby achieving both stiffness and adhesion.

[0055] In the detection device 20 for a physical quantity, the first adhesive 401, which exhibits high adhesive strength (a high Young's modulus), is applied to the proximal end of the measuring unit 113, which is a section requiring strength and extends from the proximal end towards the distal end. A second adhesive 402, which exhibits high thixotropy, is applied to the underpass 134, which requires a sealing structure, and to the perimeter of the chip package 310. That is, the first adhesive, which has higher adhesive strength than the second adhesive, which has high elasticity, is applied in the bonding area so that it extends from the proximal end towards the distal end of the measuring unit 113.

[0056] As previously described, by applying the first adhesive 401, which has a high Young's modulus, to the proximal end of the measuring unit 113 and the section extending from the proximal end, the bond strength between the section on the proximal end of the housing 100 and the cover 200 can be increased, and the stiffness of the entire device can be improved. Furthermore, by applying an adhesive exhibiting high thixotropy along the underpass 134, it is possible to maintain a mold in which a gap is filled at the time of application, thus preventing deformation of the mold before and after curing and ensuring a seal between the circuit chamber 135 and the underpass 314 around the chip package 310.Therefore, both stiffness and adhesion can be achieved, the vibration of the measuring unit 113 at the time of vibration can be suppressed by improving stiffness, the load acting on the measuring unit 113 can be reduced, the thickness of the measuring unit 113 can be reduced, and the pressure loss reduction effect can be achieved.

[0057] In the detection device 20 for a physical quantity of this embodiment, the pair of adhesive grooves 162 and 163 of the first adhesive groove 160A extends from the proximal end of the measuring unit 113 to the side of the distal end of the housing (upstream side with respect to the main flow of the underpass) with respect to the upstream end of the measuring unit (thin film section) of the flow rate sensor element 311. The first adhesive is applied to the first adhesive groove 160A. The distance between the measuring unit of the sensor element 311 and the wall surface facing the measuring unit significantly affects the flow rate detection accuracy.Since the first adhesive is applied so that it extends to the upstream side of the measuring section in the main flow direction of the underpass, it is possible to suppress deformation of the passage shape near the measuring section of the sensor element due to vibration, and thus the measuring accuracy of the flow meter is improved.

[0058] More precisely, the pair of adhesive grooves 162 and 163 extends from the proximal end of the measuring unit 113 to the side of the distal end of the housing (upstream side with respect to the main flow of the underpass) with respect to the section of the upstream end of the chip package 310, which is the carrier of the sensor element 311, and the first adhesive is applied to the first adhesive groove 160A. At the upstream end of the chip package 310, the fluid flows separately to the front surface (side of the measuring unit) and to the rear surface.By applying the first adhesive so that it extends towards the upstream side in the main flow direction of the underpass from the upstream end of the chip package 310, it is possible to suppress deformation of the passage shape near the flow separation section due to vibration, and it is possible to suppress fluctuation of the flow separation ratio, thus further improving the flow rate accuracy.

[0059] Furthermore, in the detection device 20, the groove section 164 of the first adhesive groove 160A is provided for a physical quantity, such that it extends in the X-axis direction from the intermediate position of the groove section 161 towards the side of the distal end of the housing 100. The first adhesive 401, which has a high Young's modulus, is applied to the groove section 164. Therefore, the stiffness of the entire device is further improved, and the influence of vibration and thermal stress can be reduced. It should be noted that in the embodiment described above, the case where the number of groove sections 164 is one was described as an example; however, multiple groove sections can be provided, and the stiffness of the entire device can be further improved by increasing the number of groove sections 164. <Zweite Ausführungsform>

[0060] Next, the detection device 20 for a physical quantity according to a second embodiment of the present invention is described with reference to Fig. 11 described. The same components as those of the first embodiment are designated with the same reference numerals and their detailed description is omitted.

[0061] A characteristic feature of this embodiment is that the circuit board 300 is included in the circuit chamber 135 and the chip package 310 and the pressure sensor 320 are mounted on the circuit board 300.

[0062] Circuit chamber 135 and the second sub-passage B are connected by a pressure control passage 170, and the pressure of the second sub-passage B can be applied to circuit chamber 135. The pressure sensor 320, mounted on the circuit board 300 in circuit chamber 135, can detect the pressure applied to circuit chamber 135 from the second sub-passage B through pressure control passage 170.

[0063] The second adhesive groove 160B is formed at a boundary section between the circuit chamber 135 and the second underpass groove 152, and the second adhesive 402 is applied to the second adhesive groove 160B. Therefore, it is possible to seal the boundary section between the circuit chamber 135 and the second underpass groove 152, preventing the target gas 2 from directly entering the circuit chamber 135 from the second underpass B and protecting the mounting component of the printed circuit board 300 from being exposed to the substance, such as the gas contained in the target gas 2.

[0064] Furthermore, in this embodiment, a circuit component (not shown) is mounted on the circuit board 300 and sealed by a silicone gel, which is a silicone-based sealing element. This prevents these circuit components from being exposed to a substance, such as a gas, in the circuit chamber 135, and protects the mounting components.

[0065] The embodiments of the invention have been described up to this point; however, the invention is not limited to these embodiments. Various modifications can be made that do not depart from the concept of the invention disclosed in the claims. For example, the embodiments of the invention described above have been described in detail in a clearly understandable manner, and they are not limited to those embodiments that exhibit all of the described features. Furthermore, some features of a particular embodiment can be replaced by features of other embodiments, and features of other embodiments can be added to the features of the embodiment in question. Additionally, some features of each embodiment can be omitted, replaced by other features, and added to other embodiments. Reference symbol list 2 Target gas 20 Detection device for a physical quantity 100 cases 135 Circuit chamber (sensor chamber) 160 adhesive groove 160A first adhesive groove 160B second adhesive groove 200 Coverage 310 Chip Package 311 Flow rate sensor (sensor element) 320 pressure sensor 401 first adhesive 402 second adhesive B second sub-pass B1 Approach - Passage Section B2 Return Transit Section

Claims

[1] Detection device (20) for a physical quantity, comprising: a housing (100) which is inserted from one side of a distal end through an insertion hole of a main passage (22) through which a target gas flows and is arranged in the main passage (22); a cover (200) which, in conjunction with the housing (100), forms a lower passage (134, B) which draws in a portion of the target gas flowing through the main passage (22); a carrier body which is received in the housing (100); and a sensor element (311) which is carried through the carrier body and arranged in the underpass (134, B), wherein the housing (100) has: a first adhesive groove (160A) comprising a groove section (161) of a proximal end extending along a proximal end of the housing (100), and a pair of groove sections (162, 163) extending from the groove section (161) of the proximal end to a side of a distal end of the housing (100) with respect to a measuring unit (113) of the sensor element (311), wherein a first adhesive (401) is applied to the first adhesive groove (160A); and a second adhesive groove (160B) extending along the underpass (134, B) and onto which a second adhesive (402) is applied, and the first adhesive (401) has a Young's modulus that is higher than that of the second adhesive (402), and the second adhesive (402) has a thixotropy that is higher than that of the first adhesive (401). [2] Detection device (20) for a physical quantity, comprising: a housing (100) which is inserted from one side of a distal end through an insertion hole of a main passage (22) through which a target gas flows and is arranged in the main passage (22); a cover (200) which, in conjunction with the housing (100), forms a lower passage (134, B) which draws in a portion of the target gas flowing through the main passage (22); a carrier body which is received in the housing (100); a sensor element (311) which is carried by the carrier body and arranged in the underpass (134, B); and a printed circuit board (300) on which the carrier body is mounted, wherein the housing (100) has: a first adhesive groove (160A) comprising a groove section (161) of a proximal end extending along a proximal end of the housing (100) and a pair of groove sections (162, 163) extending from the groove section (161) of the proximal end to a side of a distal end of the housing (100) with respect to a measuring unit (113) of the sensor element (311), wherein the first adhesive groove (160A) is provided with a first adhesive (401); a circuit chamber (135) which accommodates the circuit board (300); and a second adhesive groove (160B) which is provided near the carrier body between the circuit chamber (135) and the underpass (134, B) and is provided with a second adhesive (402), and the first adhesive (401) has a Young's modulus that is higher than that of the second adhesive (402), and the second adhesive (402) has a thixotropy that is higher than that of the first adhesive (401). [3] Detection device (20) for a physical quantity according to claim 1 or 2, wherein the pair of groove sections (162, 163) extends to one side of a distal end of the housing (100) from the carrier body. [4] Detection device (20) for a physical quantity according to claim 3, wherein the first adhesive groove (160A) has an intermediate groove section (164) which extends from an intermediate position in an extension direction of the groove section (161) of the proximal end towards a side of a distal end of the housing (100). [5] Detection device (20) for a physical quantity according to claim 4, wherein the intermediate groove section (164) has a groove width that is an even multiple of the groove widths of the groove section (161) of the proximal end and of the pair of groove sections (162, 163). [6] Detection device (20) for a physical quantity according to claim 4, wherein the intermediate groove section (164) has a groove width which is twice the groove widths of the groove section (161) of the proximal end and of the pair of groove sections (162, 163). [7] Detection device (20) for a physical quantity according to claim 2, wherein a circuit component is mounted on the printed circuit board (300) and sealed with a silicone-based sealing element. [8] Detection device (20) for a physical quantity according to claim 3, wherein the first adhesive (401) is an epoxy-based adhesive and the second adhesive (402) is a silicone-based adhesive.

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