JP6332932B2 - Manufacturing method of thermal flow rate / flow rate sensor and thermal flow rate / flow rate sensor - Google Patents

Description

  The present invention relates to a flow velocity / flow rate sensor manufacturing method and a flow velocity / flow rate sensor for measuring a flow velocity and a flow rate of a fluid, and more particularly, to a heater element that generates heat by a supply current and a temperature from the heater element that changes according to the flow velocity. The present invention relates to a method of manufacturing a thermal flow rate / flow rate sensor and a flow rate / flow rate sensor for manufacturing a flow rate detection unit having a temperature measuring element to be detected and an air temperature measurement element for measuring an air temperature by using mounting parts.

  In general, when a heater element such as a heating wire is placed in a fluid, a thermal flow rate / flow rate sensor utilizes the fact that the amount of heat from the heater element deprived by the fluid changes depending on the fluid flow rate. The flow rate is measured and the flow rate of the fluid is calculated from the result. The flow rate / flow rate sensor generally includes a temperature compensation element so that the influence of the change in temperature on the output (heat amount) from the flow rate detection unit can be compensated when the temperature of the fluid to be detected for the flow rate changes. ing.

Here, the operation principle of a general thermal flow rate / flow rate sensor will be described.
First, when a heating element having a constant heat source is present in the fluid, a physical phenomenon is used in which the heat of the heating element moves to the fluid according to the flow velocity. This physical phenomenon is generally known as the King equation, as shown in the following equation (1).

Q = (a + bu) (T−Ta) Formula (1)
Here, Q is the amount of heat generated by the heating element, u is the flow velocity, T is the temperature of the heating element, Ta is the temperature of the surrounding fluid, and a and b are constants, which depend on the material and structure of the heating element.

  From the above equation (1), in order to measure the flow velocity, when the calorific value Q is constant, the temperature of the heating element temperature T and the temperature Ta of the surrounding fluid must be measured. Further, when the heat generation amount Q is indefinite, the heat generation amount Q, the heating element temperature T, and the temperature Ta of the surrounding fluid must be measured and obtained. In addition, since a and b are values depending on the material and structure of the heating element, if the material and structure are the same, in principle, a and b are also determined values.

  FIG. 12 shows Conventional Example 1. In order to cause the wind speed detection sensor to self-heat, a booster circuit 60, a constant current circuit 61, a current-voltage conversion circuit 62, and the like are required as a control circuit for the wind speed detection element 63. is there. The wind speed detecting element 63 is not necessarily required when the platinum resistor is used. Further, in the case of the wind speed detecting element 63 of the conventional example 1, it is converted into a voltage value by using a bridge circuit, this voltage value is amplified, and the flow velocity value is calculated by the wind speed value converting section 64 of the computer processing unit. Yes. The reference resistor 65 and the air temperature detection element 66 measure the temperature of the surrounding fluid.

  At this time, high-precision and relatively expensive parts are used for the bridge circuit, and the bridge circuit needs to be adjusted at the time of shipment or installation. Further, for the constant current circuit 61 and the current-voltage conversion circuit 62, it is necessary to perform operations such as adjustment of individual differences in circuit characteristics and recording to a computer.

  Also, elements suitable as elements for detecting the wind speed are limited parts or custom-made products. In particular, when a platinum resistor is used, the characteristics are standardized, but most of them are provided by custom-made products, which causes high costs. Furthermore, the temperature measuring element for detecting the heating element temperature T and the heater as the heat source are composed of the same element, which is also one of the causes of high cost.

  Therefore, as a means for solving the high cost by configuring the temperature measuring element for detecting the heating element temperature T and the heater as the heat generation source with the same element, as shown in FIG. A circuit configuration separated into the heater 71 has been proposed. 75 is a reference resistance, 76 is an air temperature detecting element, and 74 is a wind speed value conversion (such as a microcomputer).

  In the case of the circuit configuration of FIG. 13, the wind speed detecting element 73 for detecting the heating element temperature T and the heater 71 are thermally connected directly. That is, they are physically joined. When the circuit configuration shown in FIG. 13 is compared with the circuit configuration shown in FIG. 12, the circuit configuration shown in FIG. 13 is simplified. Therefore, the cost can be reduced correspondingly.

  On the other hand, the thing of the prior art example 2 shown in FIG. 14 is a prototype in which the inventor constituted the flow velocity detection part by the element (the heater element 80 and the temperature measuring element 81) with a lead wire, and the heater element 80 and the temperature measuring element 81 is a flow velocity / flow rate sensor having a structure separated from 81. In this prototype, a heater element 80 connected to a heater power supply 82 for heating and a temperature measuring element 81 for measuring the temperature of heat transmitted from the heater element 80 are connected via a lead wire 83. ing.

  Therefore, the heat conduction speed of heat conducted from the heater element 80 to the temperature measuring element 81 via the lead wire 83 is poor, and it takes time to increase the temperature of the temperature measuring element 81 once the heat is deprived. In addition, there is a problem that the heat conduction speed fluctuates depending on the connection position of the lead wire 83 and the amount of solder at the time of soldering for connection, which is far from cost reduction and practical use.

  Therefore, as a means for solving the problems of the prototype of the inventor (conventional example 3), a method of forming a heater and a temperature measuring element for detecting a flow rate on a thin plate-like material of 1 mm or less has been put into practical use. ing. This is a method in which an element is directly formed on a surface of a plate-like substrate by chemical treatment such as vapor deposition or etching.

  In this thermal flow rate / flow rate sensor, a flow rate detection unit and an air temperature measurement unit are provided on a single substrate such as a silicon substrate or other electronic substrate, and the flow rate detection unit must be heated by a heater. . Therefore, when the flow velocity detection unit and the temperature measurement unit are provided on a single substrate, the temperature measurement unit is affected by the heat from the flow velocity detection unit that travels through the substrate and cannot accurately measure the temperature. There is a problem.

  Therefore, in the conventional example 4 shown in FIGS. 15A and 15B, a ceramic substrate 90 having low thermal conductivity is used as a substrate member of the thermal wind speed sensor, and one end side of the ceramic substrate 90 is used. The wind speed detecting sensor RH and the temperature measuring sensor RT, which is a temperature compensating sensor, are directly formed on the other end side by printing or vapor deposition of a platinum material. In this way, by arranging the wind speed detection sensor RH and the temperature measurement sensor RT on both ends of the same ceramic substrate 90 via the gap, the temperature measurement sensor RT is separated from the wind speed detection sensor RH transmitted through the ceramic substrate 90. It is configured so as not to be affected by the heat of as much as possible. Reference numeral 91 denotes a hybrid IC.

  In the case of the conventional example 5 shown in FIG. 16, the thermistor (fluid temperature detecting element) 102 and the flow rate detecting portion of the thermal flow rate / flow rate sensor 100 may be damaged by an external impact, The protector 101 that protects the thermistor 102 is integrated as a unit. Thus, the thing of the structure integrated as a unit is already integrated as a unit at the time of pipe attachment, and is not manufactured by integral molding. Also, in order to prevent burns due to heat generation in the flow rate detection unit, a protective guard such as the protector 101 is necessary, and this protective guard is generally manufactured as a separate part and must be combined. Reference numeral 103 denotes a detection passage, 104 denotes a circuit case, and 105 denotes a structure.

JP-A-10-274552 JP 2008-241318 A JP-A-6-249864 Japanese Patent No. 3553422

  The element for detecting the flow velocity described in the conventional example 1 shown in FIG. 12 has a size of several millimeters to several tens of millimeters. It is necessary to extend and fix the lead wire, and it is not possible to use an automatic assembly machine (automatic mounting machine) such as an electronic component automatic mounting machine that is generally used. For this reason, there is only a method for manually assembling or creating a new automatic assembly machine as a custom-made product and using it, which also causes high costs.

  Furthermore, the wind speed detecting element 63 of the conventional example 1 uses a temperature measuring element such as a platinum resistor or a thermistor in the wind speed detecting section, and is supported by a thin copper wire attached to the temperature measuring element. However, the structure supported by the copper wire is weak against mechanical impacts, and moreover, because it is a metal, it is not suitable for long-term continuous use due to damage caused by rust or corrosion. Therefore, in order to improve the durability, there is an option of thickening the wind speed detecting element 63 and the attached copper wire, but in this case, the response is poor and the performance deteriorates, so it is not realistic. There's a problem.

  Further, as shown in FIG. 13, the circuit configuration for detecting the heating element temperature T is simplified, compared with the circuit configuration shown in FIG. 12, and the cost is reduced. However, there is a problem of physical joining when the wind speed detecting element 73 for detecting the heating element temperature T and the heater 71 are directly connected thermally. That is, if the physical connection between the wind speed detection element 73 and the heater 71 is not constant to some extent, the difference in solids increases, and the labor for fixing adjustment as a flow velocity / flow rate sensor increases. When the individual difference is large, the constant a and the constant b must be obtained for each individual, as is apparent from the King equation shown in the above equation (1). Therefore, there is a problem that the labor for product adjustment increases and the compatibility of the detection unit is also poor.

  Further, when the distance between the heat conducting surfaces of the heater 71 and the wind speed detecting element 73 is increased, there is a problem that the responsiveness is deteriorated.

  In addition, there is a flow velocity detecting element manufactured using MEMS (Micro Electric Mechanical System: hereinafter referred to as MEMS) which is a method of manufacturing a device using a semiconductor manufacturing process. By using this MEMS, manufacturing of the element is possible. Some are automated in the process. However, in general, in MEMS, the higher the production quantity, the lower the unit manufacturing cost of an element. However, the plate cost of MEMS is very expensive, especially compared to the plate cost in a general plate-shaped electronic substrate manufacturing method. In the case of a product with a small production quantity, there is a problem that the unit sales price of the element becomes high. In addition, since the plate cost is very expensive as described above, there is a problem that there is a cost limitation when customizing elements or developing variations.

  Further, as described in the conventional example 2, the heater element 80 and the temperature measuring element 81 are separated and the heater element 80 and the temperature measuring element 81 are connected via the lead wire 83. There is a problem that the heat conduction speed when heat is conducted from the heater element 80 to the temperature measuring element 81 through 83 is poor, and it takes time to increase the temperature of the temperature measuring element 81 once the heat is deprived. In addition, there is a problem that the heat conduction speed varies depending on the connection position of the lead wire 83 and the amount of solder at the time of soldering for connection.

  In addition to the elements described in the conventional example 2, in general, when increasing the temperature of the flow velocity detection unit for detecting the flow velocity, in order to secure a heat generation amount with a small amount of electric energy, a lead wire is preferably used. Although it is necessary to reduce the amount of heat dissipated through the lead wire by making it thin, there is a problem that if the lead wire is made thin, it becomes weak against mechanical shock.

  In addition, as described in the conventional example 3, in the method of directly forming an element on the surface of a plate-like substrate by chemical treatment such as vapor deposition or etching, chemical treatment such as vapor deposition or etching is performed. Equipment and equipment, microfabrication technology, and technical fields that require accumulation of know-how to improve accuracy, manufacturing technology is not easy, and it is far from cost reduction unless mass production is performed. There is.

  The thing of the prior art example 4 shown in FIG. 15 presupposes measuring the wind speed in a duct, and there exists a problem that it can be used only when an airflow is unidirectional. Further, since a distance is provided between the wind speed detection sensor RH and the temperature measurement sensor RT, the air in which the wind speed detection sensor RH and the temperature measurement sensor RT are in contact particularly in the case of a slight wind speed. The effect on measurement accuracy due to different conditions must be taken into account. Further, since it is assumed that the hybrid IC 91 is arranged at the center of the ceramic substrate 90, there is a problem that it is necessary to consider the influence of the turbulence of the air flow by the hybrid IC 91 on the measurement value. In addition, if the distance between RH and RT is shortened, the influence of heat conduction cannot be ignored, so there is a problem that there is a limit to downsizing.

  In the case of the conventional example 5 shown in FIG. 16, when there is a possibility that the flow rate detection part of the thermal flow rate / flow rate sensor is damaged by an external impact, the flow rate detection part is protected by a protective guard or the like. In addition, in order to prevent burns due to heat generation in the flow velocity detection unit, a protective guard is necessary, and this protective guard is a probe-shaped protective guard, but is generally manufactured and combined as a separate part. Therefore, there is a problem that manufacturing costs and assembly costs occur.

  In view of the many problems described above, the present invention provides a method of manufacturing a thermal flow rate / flow rate sensor and a thermal flow rate / flow rate sensor, and a heat generation part (heater element) for detecting a flow rate and the temperature of heat from the heat generation unit. A single plate-like substrate is used as the substrate for the flow velocity detection unit for measuring the flow rate, and a general-purpose substrate manufacturing apparatus is used, and further, electronic components mounted on the flow velocity detection unit use a general-purpose automatic mounting machine. The first object is to form a flow velocity detection unit by mounting general-purpose surface mount components, and by providing a space between the flow velocity detection unit and the air temperature measurement unit, the flow velocity detection unit The second object is to reduce heat conduction from the heat generating part to the temperature measuring part. In addition, by providing a space around the temperature measurement unit to further reduce the heat conduction from the heat generation unit of the flow rate detection unit, the third effect is to reduce the influence of the heat from the flow rate detection unit on the temperature measurement unit. The purpose is. In addition, by providing a guard that protects the flow velocity detector that has a structure protruding from the substrate, it is possible to prevent damage to the thermal flow velocity / flow sensor due to external impact and to prevent burns due to erroneous contact of the flow velocity detector. The purpose of 4 is.

The invention according to claim 1 is a fluid flow velocity comprising a heater element that generates heat by a supply current, and a flow velocity detector having a temperature measuring element that detects the temperature of the heat from the heater element that changes according to the flow velocity. And a method of manufacturing a thermal flow rate / flow rate sensor for measuring the flow rate,
The heater element and the temperature measuring element are general-purpose surface-mount components, and from a single substrate of the thermal flow rate / flow rate sensor, the belt-shaped outer peripheral portion constituting the main part of the substrate, which is the main part of the substrate, A pair of elongated flow velocity detecting portion support portions integrally formed with the substrate and extending integrally from the main portion of the substrate constituting the belt-shaped outer peripheral portion toward the center, and the pair of flow velocity detection portion support portions A substrate portion on which the flow velocity detection unit supported at the tip is mounted integrally with the main portion of the substrate, a circuit pattern for the flow velocity detection portion is formed on the substrate portion on which the flow velocity detection portion is mounted, and the flow velocity detection portion is A heater element is mounted on one surface of the surface mounting part of the board part to be mounted, and the temperature measuring element is placed opposite to the surface mounting part of the heater element, and the surface mounting part of the board part on which the flow velocity detector is mounted. Mounted on the other side of the heater element and temperature sensor Is installed on both surfaces of the surface mounting part of the board part where the flow rate detection unit is mounted, and the heater element and the temperature measuring element are thermally connected directly via the board part at the surface mounting part. A surface mounting portion of the substrate portion on which the detection portion is formed and the flow velocity detection portion is mounted, a pair of flow velocity detection portion support portions extending integrally from the surface mounting portion to the main portion of the substrate, and a belt-shaped outer peripheral portion. By leaving the peripheral part of the substrate, the main part of the substrate constituting the belt-shaped outer peripheral part is used as a guard part for protecting the flow rate detection part, and a space is provided around the flow rate detection part. And a method of manufacturing a thermal flow rate / flow rate sensor formed using a general-purpose substrate manufacturing apparatus.

According to a second aspect of the present invention, a flow rate detector having a heater element that generates heat by a supply current, and a temperature measuring element that detects the temperature of the heat from the heater element that changes in accordance with the flow rate, and measures the temperature. In the manufacturing method of the thermal flow rate / flow rate sensor for measuring the flow rate and flow rate of the fluid comprising the temperature measurement unit having the temperature measurement element,
The heater element, temperature measuring element, and air temperature measuring element are general-purpose surface-mount components, and a belt-shaped structure that forms the main part of this board from a single plate-like board of the thermal flow rate / flow rate sensor The outer peripheral part is formed integrally with the substrate, and a slender flow rate detection part support part integrally extending from the main part of the substrate is formed integrally with the substrate at the central part of one end of the substrate. At the tip of the support part for the part, the substrate part for mounting the flow velocity detection part is formed so as to be positioned at the center part of the belt-like outer peripheral part, and the circuit pattern for the flow velocity detection part is formed on this substrate part, A circuit pattern for the air temperature measurement unit is formed on the surface, and the heater element and the temperature measurement element are mounted adjacent to each other on the surface mounting portion of the board portion on which the flow velocity detection unit is mounted. Thermally connected directly to the temperature element A speed detector is formed, an air temperature measuring unit is formed by mounting an air temperature measuring element on the surface mounting part of the belt-shaped outer periphery, and the surface mounting part of the substrate part on which the flow velocity detecting part is mounted and the surface mounting part The flow rate detection unit formed at the surface mounting location is cut for the flow rate detection unit by cutting the peripheral part of the substrate, leaving the support for the flow rate detection unit extending integrally to the main part of the substrate and the belt-shaped outer periphery. It is formed in a structure that is supported by the main part of the substrate by the support part, and the main part of the substrate constituting the belt-shaped outer peripheral part is used as a guard part that protects the flow rate detection part, and a space is provided around the flow rate detection part and the temperature measurement element. A thermal flow velocity / flow rate formed using a general-purpose substrate manufacturing device so that a space is provided between the flow velocity detection unit and the air temperature measurement element, and a plate-shaped substrate main part is provided. It is a manufacturing method of a sensor.

According to a third aspect of the present invention, there is provided a fluid flow velocity comprising a heater element that generates heat by a supply current, and a flow velocity detection unit that includes a temperature measuring element that detects the temperature of heat from the heater element that varies according to the flow velocity. And in the thermal flow rate / flow rate sensor that measures the flow rate,
A single plate-like substrate of the thermal flow rate / flow rate sensor, a belt-like outer peripheral portion constituting the main portion of the substrate integrally formed from this substrate, and a main substrate constituting this belt-like outer peripheral portion A pair of elongated flow velocity detecting portion support portions integrally extending from the first portion toward the center, and a pair of flow velocity detection portion support portions that are supported at the distal ends of the pair of flow velocity detection portion support portions and integrally formed with the main portion of the substrate. A circuit board portion for mounting the flow velocity detection unit, a circuit pattern for the flow velocity detection unit formed on the substrate part,
A heater element that is a general-purpose surface-mounted component mounted on one surface of a surface mounting portion of a substrate portion on which a flow velocity detection unit is mounted, and a substrate portion that mounts a flow velocity detection portion facing the surface mounting portion of the heater element. Mount the temperature sensor, which is a general-purpose surface-mounted component mounted on the other surface of the surface-mounted part, and the heater element and the temperature sensor on both surface-mounted parts of the board part where the flow velocity detector is mounted. From the flow rate detection unit in which the heater element and the temperature measuring element are thermally connected directly via the substrate part in the surface mounting location, the surface mounting location of the substrate portion on which the flow rate detection unit is mounted, The main substrate constituting the belt-shaped outer peripheral portion is formed by cutting the peripheral portion of the substrate while leaving a pair of flow velocity detecting portion supporting portions integrally extending from the surface mounting portion to the main substrate portion and the belt-shaped outer peripheral portion. Part, flow With a guard portion for protecting the detector, so that a structure in which a space around the flow rate detecting unit, a thermal type flow rate-flow sensor formed by using a general-purpose substrate manufacturing apparatus.

According to a fourth aspect of the present invention, a flow rate detector having a heater element that generates heat by a supply current, and a temperature measuring element that detects a temperature of heat from the heater element that changes in accordance with the flow rate, and measures the temperature. In a thermal flow rate / flow rate sensor that measures the flow rate and flow rate of a fluid consisting of an air temperature measurement unit having an air temperature measurement element,
A single plate-like substrate of the thermal flow rate / flow rate sensor, a belt-shaped outer peripheral portion constituting the main portion of the substrate, which is the main portion of the substrate integrally formed from this substrate, and a substrate at one central portion of this substrate And a flow rate detecting portion supporting portion formed in an elongated shape integrally extending from the main portion of the substrate, and formed at the tip portion of the flow velocity detecting portion supporting portion, and at the center portion of the belt-shaped outer peripheral portion A circuit board part for mounting a flow velocity detection unit formed so as to be located on the substrate, a circuit pattern for the flow velocity detection unit formed on the substrate part, a circuit pattern for the air temperature measurement unit formed on the belt-shaped outer periphery, and a flow rate A heater element formed by mounting a heater element, which is a general-purpose surface-mounted component, and a temperature-measuring element, which is a general-purpose surface-mounted component, arranged adjacent to each other and mounted on a surface-mounted portion of a substrate portion on which the detection unit is mounted And temperature sensor A flow rate detection unit that is directly connected thermally, a temperature measurement element that is a general-purpose surface-mounted component mounted on a surface-mounted location on the outer periphery of the belt, and a surface-mounted location on the board portion on which the flow rate detection unit is mounted, The flow velocity detector formed at the surface mount location is cut by cutting the peripheral portion of the substrate, leaving the support portion for the flow velocity detection portion extending integrally from the surface mount location to the main part of the substrate and the belt-shaped outer peripheral portion. The substrate main part that forms the belt-shaped outer peripheral part is formed as a guard part that protects the flow rate detecting part, and the flow rate detecting part and the temperature measuring element In addition, a space is provided between the flow velocity detection unit and the temperature measurement element, and a general substrate manufacturing apparatus is used so that a plate-like substrate main part is provided. Thermal flow rate / flow rate sensor It is.

Since the invention according to claim 1 and claim 3 is configured as described above, when the flow velocity detecting portion support portion 9 is formed of the same member as the substrate portion 1a, it is necessary to make it thin like a conventional lead wire. And there is an effect that the mechanical strength becomes higher. Further, the flow velocity detection unit 5 uses a heater element 4 which is a general-purpose electronic component for surface mounting and a temperature measuring element 3 which measures the temperature of heat from the heater, and a method for manufacturing a plate-shaped electronic substrate. Since each electronic component can be mounted on a board by an automatic mounting machine generally used in the above, the assembly process can be automated easily, and the assembly cost is very low.

  Moreover, since the heater element 4 and the temperature measuring element 3 have a structure in which they are thermally connected directly via the board portion 1a of the mounting location, a flow rate detection unit 5 with good responsiveness can be obtained, and an individual Since the flow velocity detection unit 5 with little difference is obtained, adjustment as a sensor is not required, and the cost is reduced. Moreover, since the heater element 4 and the temperature measuring element 3 have a structure in which they are thermally connected directly via the board portion 1a of the mounting location, a flow rate detection unit 5 with good responsiveness can be obtained, and an individual Since the flow velocity detection unit 5 with little difference is obtained, adjustment as a sensor is not required, and the cost is reduced.

  In addition, a flow rate detecting element manufactured using MEMS (Micro Electric Mechanical System), which is a device manufacturing method using a general semiconductor manufacturing process, is not suitable for a small number of production because the plate cost is expensive. At the same time, there are restrictions on customization and variation development. However, in the case of the present invention, a plate-shaped electronic substrate is manufactured using a general-purpose substrate manufacturing apparatus and a commonly used automatic mounting machine can be used. The cost of the initial cost on the manufacturing unit price is negligible compared with MEMS because the cost is the same as for the electronic substrate. Furthermore, since there are currently automatic assembly machines that can handle products with a small production quantity, even a product with a small production quantity will not be extremely expensive. In addition, since the initial cost can be kept low, customization and variation development are easy.

In addition, general-purpose electronic components with stable accuracy can be used, and a commonly used automatic mounting machine can be used, so a low-cost thermal flow rate / flow rate sensor with little individual difference can be obtained.

  Furthermore, the flow velocity detection portion support portion 22 can be formed in its shape (width, length, etc.) according to the desired thermal conductivity, and the flow velocity detection portion 20 is supported by the flow velocity detection portion support portion 22. The substrate material of the substrate 21 and the flow velocity detection unit support portion 22 is a member having a low thermal conductivity similar to that of the substrate portion 1a of the first embodiment (FR-4 substrate: thermal conductivity is 0.45 W). / M / K) is used. In addition, by forming the flow velocity detection portion support portion 22 to be elongated, heat conduction from the flow velocity detection portion 20 to the substrate main portion 21 b of the substrate 21 can be suppressed, and further, the flow velocity detection portion support portion 22 is fixed through the mounting hole 23. It is also possible to suppress heat conduction to other devices.

Since the inventions according to claims 2 and 4 are configured as described above, the same effects as the inventions according to claims 1 and 3 are obtained, and the flow velocity detection unit 40 to the substrate main part 41b is provided. Heat conduction can be reduced. Furthermore, the heat conduction can be further reduced by forming the support portion 42 for the flow velocity detection portion to be thin. A space 47 is formed between the flow velocity detection unit 40 and the air temperature measurement unit 44, and a space 46 is also formed around the flow velocity detection unit 40 and the air temperature measurement unit 44. In addition, by forming the temperature measurement unit support 43 of the temperature measurement unit 44 to be thin, the heat conduction to the temperature measurement unit 44 can be further reduced, and the heat from the flow velocity detection unit 40 is measured by the temperature measurement. The influence on the portion 44 can be reduced as much as possible.

Further, even when the temperature of the temperature measuring element 3 is lowered, the temperature of the temperature measuring element 3 can be recovered more quickly by the heater element 4 which is arranged so as to sandwich the temperature measuring element 3 and the number thereof is increased. Responsiveness as a thermal flow rate / flow rate sensor can be improved.

Furthermore, the guard part 56 can protect the flow velocity detection part 50 in a state of protruding from the substrate main part 51 b via the flow velocity detection part support part 52. Furthermore, the guard part 56 can also prevent burns caused by erroneous contact with the heater element 4 that generates heat in the flow velocity detection part 50. The guard 56 can be integrally formed with the substrate by a numerically controlled machine (hereinafter referred to as NCM) or the like in the substrate manufacturing stage, thereby greatly reducing manufacturing and assembly costs. I can do it.

It is a principal part schematic diagram which shows the 1st Example of this invention. It is a principal part schematic diagram which shows the 2nd Example of this invention. It is a principal part schematic diagram which shows the 3rd Example of this invention. It is a principal part schematic diagram which shows the 4th Example of this invention. The 4th Example of this invention is shown and it is a principal part schematic diagram which shows a modification. It is the heat distribution curve which shows the top view of the prototype A for the comparative experiment with the prototype of this invention, and the result of a heat conduction experiment. It is the heat distribution curve which shows the result of the top view of the prototype B of this invention, and a heat conduction experiment. It is a heat distribution curve which shows the result of the top view of the prototype C of this invention, and a heat conduction experiment. It is a heat distribution curve which shows the result of the top view of the prototype D of this invention, and a heat conduction experiment. It is a heat distribution curve which shows the result of the top view of the prototype E of this invention, and a heat conduction experiment. It is a principal part schematic diagram which shows the 5th Example of this invention. It is a block diagram at the time of comprising the temperature measuring element for detecting the heat generating body temperature T, and the heater element used as a heat-generation source by the same element, showing the prior art example 1. It is a block diagram at the time of comprising the temperature measuring element for detecting the heat generating body temperature Th, and the heater element used as a heat-generation source by a separate element which shows the prior art example 2. FIG. It is a principal part block diagram of the flow velocity and the flow sensor which showed the prior art example 3, and was invented as a trial. It is a principal part block diagram of the flow velocity and flow volume sensor which shows the prior art example 4. FIG. It is a principal part block diagram of the flow velocity and flow volume sensor which shows the prior art example 5. FIG.

  A flow rate of fluid comprising a heater element, which is a general-purpose surface-mounted component that generates heat by a supply current, and a temperature measuring element that detects the temperature of heat from the heater element that changes according to the flow rate; and In the manufacturing method of the thermal flow rate / flow rate sensor that measures the flow rate, the heater element and the temperature measuring element are general-purpose surface-mount components, and on both sides of one end of the plate-like single substrate of the thermal flow rate / flow rate sensor, The elongated flow velocity detecting portion support portion and the temperature measuring portion support portion that are integrally extended from the substrate main portion, which is the main portion of the substrate, are formed integrally with the substrate so as to be separated from each other. Further, a substrate portion on which the flow velocity detection unit is mounted is formed at the tip of the flow velocity detection portion support portion, and a circuit pattern for the flow velocity detection portion is formed on the substrate portion. A substrate part for mounting the temperature measurement unit is formed at the tip of the temperature measurement unit support part, and a circuit pattern for the temperature measurement unit is formed on the substrate part. A flow rate in which a heater element and a temperature measuring element are directly connected to each other by mounting the heater element and the temperature measuring element adjacent to each other on the surface mounting portion of the substrate portion on which the flow rate detecting unit is mounted. A detection unit is formed. An air temperature measurement unit formed by mounting an air temperature measurement element is formed on the surface mounting portion of the substrate portion on which the air temperature measurement unit is mounted.

  Next, the surface mounting portion of the substrate portion on which the flow velocity detection portion is mounted, the support portion for the flow velocity detection portion extending integrally from the surface mounting portion to the main portion of the substrate, and the surface mounting portion of the substrate portion on which the air temperature measurement portion is mounted And a flow rate detector formed at each surface mount location by cutting the peripheral portion of the substrate, leaving the temperature measurement element support portion extending integrally from the surface mount location to the main part of the substrate. The temperature measuring element is formed in a structure that is supported by the main part of the substrate by the flow velocity detection unit support and the temperature measurement element support, respectively, and a space is provided around the flow rate detection unit and the temperature measurement element. In addition, a space is provided between the flow rate detection unit and the air temperature measurement element, and a general substrate manufacturing apparatus and a general-purpose automatic mounting machine are used so as to have a structure in which a plate-like substrate main part is provided. .

  The general conditions required for a practical thermal flow rate / flow rate sensor are good measurement accuracy and responsiveness, low power consumption, and low cost. In general, electronic components such as surface-mounted components mounted on the surface of a substrate are becoming smaller, more accurate, and lower in cost. Such electronic components are generally used as distribution products. In particular, electronic components having an error accuracy of about ± 1% due to individual differences among electronic components are available as general distribution products. An automatic mounting machine for mounting these electronic components on a substrate has also been generalized, and automation has been established for a method for mounting electronic components such as surface mounting components using the automatic mounting machine. If these general-purpose electronic components and automatic mounting machines can be used, a thermal flow rate / flow rate sensor with good measurement accuracy and low cost can be realized.

  On the other hand, in order to realize a thermal flow rate / flow rate sensor with low power consumption and good responsiveness, the heat generated by the heat generation part of the thermal flow rate / flow rate sensor is transferred through the copper wire etc. It is important to suppress. In the thermal type flow velocity / flow rate sensor, the heat generating part has the highest power consumption, and the heat generated by the heat generating part escapes to other devices, that is, not only the power consumption increases, This is because it means that the responsiveness of the sensor itself is deteriorated.

  Here, as a substrate material for a substrate on which an electronic component is mounted, a member having a low thermal conductivity is generally used. For example, FR-4 (FRAME RETARDANT TYPE 4), which is often used as a substrate material, is a commonly used printed circuit board, and its strength (elastic modulus) is 55% compared to copper wire. Although it does not reach the mechanical strength of the wire, the thermal conductivity is as low as 0.1% with respect to the copper wire.

  On the other hand, in general, the heat conduction through an object depends on the cross-sectional area and temperature difference of the structure of the object. The thermal conductivity of air is 0.0241 W / m · K, and the thermal conductivity of the FR-4 substrate is 0.45 W / m · K. These thermal conductivities are lower than the thermal conductivities of copper, 403 W / m · K. Therefore, in the present invention, the thermal flow velocity / flow rate sensor is structurally provided with a portion having a low thermal conductivity that becomes a bottleneck, and a method of suppressing thermal conduction is used.

A first embodiment of the present invention will be described in detail with reference to FIG.
FIG. 1 is a schematic view of a main part showing a first embodiment of the present invention. A single plate-like substrate 1 is formed on a substrate portion 1a that forms a flow velocity detecting portion of a flow velocity / flow rate sensor and the substrate portion 1a. It is comprised by the board | substrate main part (not shown) extended. In FIG. 1, a temperature measuring unit described later is omitted.

  The plate-like single substrate 1 is not limited to this embodiment, and FR-4 made of glass epoxy, which is generally widely sold as a printed circuit board, is used in all embodiments described later. The substrate 1 may be a polyamide substrate, or a substrate formed of a member having low thermal conductivity such as a glass epoxy substrate such as FR-4 or a ceramic substrate. Yes. In this embodiment, only the substrate portion 1a on which the flow velocity detection unit 5 is formed is described, and the substrate main portion (not shown) is omitted.

  Reference numeral 2 denotes a circuit pattern for the flow velocity detection unit formed on the surface of the substrate portion 1a. General-purpose electronic components (the heater element 4 and the temperature measuring element 3) are mounted on the mounting portion of the substrate portion 1a of the flow velocity detection unit 5, respectively. Is implemented. Since the circuit pattern 2 is formed of a copper thin film, the amount of current flowing through the circuit pattern 2 is made as small as possible in order to reduce heat conduction. For that purpose, it is desirable to narrow the width of the circuit pattern 2 of the substrate portion 1a of the flow velocity detector 5 within a range allowed by the manufacturing technology of the substrate 1. When the width of the circuit pattern 2 of the substrate portion 1a is narrowed, the environmental resistance is deteriorated. Therefore, it is desirable to protect the circuit pattern 2 by forming a protective film (not shown) such as a resist film. Further, the substrate portion 1 a around the mounting location of the heater element 4 and the temperature measuring element 3 constituting the flow velocity detection unit 5 constitutes a flow velocity detection unit support 9 that supports the flow velocity detection unit 5.

  The temperature measuring element 3 is a general-purpose electronic component. In the case of this embodiment, the terminal of the temperature measuring element 3 is soldered to a corresponding portion of the circuit pattern for the flow velocity detecting portion formed on the surface of the substrate portion 1a. Fixed and implemented. Similarly, the heater element 4 is a general-purpose electronic component, and is located opposite to a corresponding portion of the circuit pattern for the flow velocity detection portion formed on the back surface of the substrate portion 1a (a mounting portion where the temperature measuring element 3 is mounted). ), The terminal of the heater element 4 is fixed by soldering and mounted. Therefore, the heater element 4 and the temperature measuring element 3 have a structure in which both sides (front surface and back surface) of the substrate portion 1a are thermally connected directly via the mounting portion of the substrate portion 1a. Reference numeral 6 denotes a pad, which is an output terminal for taking out a signal from the flow velocity detector 5.

  Since it is configured in this way, the substrate portion around the flow velocity detection unit 5 constituted by the heater element 4 and the temperature measuring element 3 acts as a flow velocity detection unit support unit 9 that supports and supports the flow velocity detection unit 5. doing. Furthermore, the board | substrate part 1a has a structure extended in the board | substrate main part (not shown).

  Next, the manufacturing method and operation of the flow rate detection unit of the flow rate / flow rate sensor will be described with reference to FIG. First, the manufacturing method of the flow velocity detection unit 5 will be described. The plate-shaped substrate is manufactured using a general-purpose substrate manufacturing apparatus and an automatic mounting machine used in a general manufacturing process of a plate-shaped electronic device substrate. A solder paste is applied to a mounting portion of the plate-like substrate portion 1a on which the circuit pattern 2 of the flow velocity detection unit 5 is formed by a solder paste printer. Next, the temperature measuring element 3 is mounted on the front surface of the substrate portion 1a by the automatic mounting machine, and the heater element 4 is the same as the back surface of the substrate portion 1a, and the mounting location opposite to the mounting location of the temperature measuring device 3. To be mounted.

  Next, the temperature measuring element 3 and the heater element 4 are soldered and fixed by a reflow furnace or a flow device. Since the heater element 4 and the temperature measuring element 3 are soldered to the mounting portions on the front and back surfaces of the substrate portion 1a, both the elements 3 and 4 are thermally directly connected via the substrate portion of the mounting portion. It has a structure. The substrate portion 1 a around the flow velocity detection unit 5 constitutes a flow velocity detection unit support 9 that supports the flow velocity detection unit 5. The substrate portion 1a extends integrally with the main portion of the substrate.

  Here, in the conventional method, when the heater element 4 is heated, a method of thinning the lead wire of the heater element 4 is generally used in order to secure a heat generation amount with a small supply power. Since metal wires such as copper and stainless steel, which are the main components of the lead wire, have high thermal conductivity, make the lead wire as thin as possible and lead it from the heater element 4 of the flow velocity detection unit 5 to the main part of the substrate or other devices. This is because it was necessary to suppress the amount of heat that escapes along the wire. On the other hand, however, when the lead wire is made thin, it becomes weak against mechanical shock, and there is a problem that the flow velocity detection unit 5 is easily damaged.

  On the other hand, as described above, the substrate material of the plate-like substrate portion 1a does not reach copper in terms of mechanical strength, but has a lower thermal conductivity than that of copper (FR-4 substrate: thermal conductivity is 0.45 W). / M / K) is used. Therefore, from the viewpoint of heat radiation from the heater element 4 of the flow velocity detection unit 5 to the main part of the substrate and other devices, the flow velocity detection unit support portion 9 is formed of the same member as the substrate portion 1a as in this embodiment. In such a case, there is no need to make it thinner as in the case of a conventional lead wire, and there is an effect that the mechanical strength becomes higher.

  Next, the operation of the flow velocity detector 5 will be described. First, the heater element 4 is heated by a current supplied from an internal power supply (not shown) of the substrate portion 1a. When the thermal flow rate / flow rate sensor is disposed in the fluid, the heat of the heater element 4 changes according to the flow rate of the fluid, and this heat is measured by the temperature measuring element 3 via the substrate at the mounting portion of the substrate portion 1a. Direct thermal conduction to The temperature of the conducted heat is measured by the temperature measuring element 3, and the flow velocity is calculated from the measured value based on the operating principle of the thermal flow velocity / flow rate sensor described above.

  Thus, the flow rate detector 5 of the thermal flow rate / flow rate sensor according to the present invention includes a heater element 4 which is a general-purpose electronic component for surface mounting, and a temperature measuring element 3 for measuring the temperature of heat from the heater, Since each electronic component can be mounted on the board by an automatic mounting machine generally used in the manufacturing method of a plate-shaped electronic board, the assembly process can be automated easily and the assembling cost is very low. .

  Moreover, since the heater element 4 and the temperature measuring element 3 have a structure in which they are thermally connected directly via the board portion 1a of the mounting location, a flow rate detection unit 5 with good responsiveness can be obtained, and an individual Since the flow velocity detection unit 5 with little difference is obtained, adjustment as a sensor is not required, and the cost is reduced.

  In addition, as described above, the flow rate detecting element manufactured using MEMS (Micro Electric Mechanical System), which is a device manufacturing method using a general semiconductor manufacturing process, is expensive because the plate cost is expensive. In addition to being unsuitable, there are restrictions on customization and variations.

  However, in the case of the present invention, a plate-shaped electronic substrate is manufactured using a general-purpose substrate manufacturing apparatus and a commonly used automatic mounting machine can be used. The cost of the initial cost on the manufacturing unit price is negligible compared with MEMS because the cost is the same as for the electronic substrate. Furthermore, since there are currently automatic assembly machines that can handle products with a small production quantity, even a product with a small production quantity will not be extremely expensive. In addition, since the initial cost can be kept low, customization and variation development are easy.

  A second embodiment of the present invention will be described in detail with reference to FIG. FIG. 2 is a schematic diagram showing the main part of a second embodiment of the present invention. The same parts as those in the first embodiment are denoted by the same names and the same numbers, and the description thereof is omitted. Also, the temperature measuring element for measuring the temperature is omitted.

As shown in FIG. 2, a flow velocity detection unit 20 supported by an elongated flow velocity detection unit support 22 extending integrally from the substrate main portion 21 b is formed at the center of one end of the plate-like substrate 21. ing. A circuit pattern (not shown) for the flow velocity detection unit is formed on the surface of the plate-like substrate portion 21a on which the flow velocity detection unit 20 is mounted, and the temperature measuring element 3 and the heater are formed on the surface mounting portion. Each element 4 is mounted by soldering to constitute a flow velocity detection unit 20. Therefore, the temperature measuring element 3 and the heater element 4 are surface-mounted on the substrate portion 1a, and the elements 3 and 4 are arranged and mounted adjacent to each other so as to be thermally connected directly. It has become.
Instead of arranging and mounting the temperature measuring element 3 and the heater element 4 adjacent to each other, as described in the first embodiment, the temperature measuring element 3 and the heater element 4 are respectively mounted on the front surface and the back surface of the substrate portion 21a. It may be made to be a structure directly connected through the heat.

The flow velocity detection portion support portion 22 that supports the flow velocity detection portion 20 is provided with the substrate main portion 21b, the temperature measuring element 3 and the heater element 4, where the substrate portion 21a is left, and the surrounding substrate is made of NCM or the like. It is formed by cutting. Accordingly, the substrate portion 21a on which the flow velocity detection unit 20 composed of the temperature measuring element 3 and the heater element 4 is formed is integrally supported by the substrate main portion 21b by the flow velocity detection unit support portion 22 having an elongated structure. It has a structure. Reference numeral 23 denotes a mounting hole for fixing the thermal flow rate / flow rate sensor to another device or the like.
Note that even if the temperature measuring element has a circuit configuration that also serves as a heater element, the temperature measuring element having such a circuit configuration is mounted on the flow velocity detection unit 20, and similarly, the flow rate detection unit support unit 22 having an elongated structure is used. If supported, the same effect can be obtained.

  Since it is configured in this manner, as in the case of the first embodiment, general-purpose electronic components with stable accuracy can be used, and automatically using a commonly used automatic mounting machine. Since it can be manufactured, a low-cost thermal flow rate / flow rate sensor with little individual difference can be obtained.

  Furthermore, the flow velocity detection unit support portion 22 can be formed in its shape (width, length, etc.) in accordance with the desired thermal conductivity, and the flow velocity detection portion 20 is supported by the flow velocity detection portion support portion 22. The substrate material of the substrate 21 and the flow velocity detecting portion support portion 22 is a member having a low thermal conductivity similar to that of the substrate portion 1a of the first embodiment (FR-4 substrate: the thermal conductivity is 0. 0). 45 W / m / K) is used. In addition, by forming the flow velocity detection portion support portion 22 to be elongated, heat conduction from the flow velocity detection portion 20 to the substrate main portion 21 b of the substrate 21 can be suppressed, and further, the flow velocity detection portion support portion 22 is fixed through the mounting hole 23. It is also possible to suppress heat conduction to other devices.

  A third embodiment of the present invention will be described in detail with reference to FIG. FIG. 3 is a schematic view showing the main part of a third embodiment of the present invention. In addition, about the same part as the 1st Example and the 2nd Example, the same name and the same number are used and the description is abbreviate | omitted. Also, the temperature measuring element for measuring the temperature is omitted.

  As shown in FIG. 3, the substrate main portion 31b of the plate-like substrate 31 is formed in a shape having a circular belt-shaped outer peripheral portion, and a pair of flow velocity detection portions extending integrally from the belt-shaped outer peripheral portion toward the center. A support portion 32 is formed. Further, a substrate portion 31 a that forms the flow velocity detection unit 30 is integrally formed at the distal ends of the pair of flow velocity detection unit support portions 32. Therefore, the substrate portion 31a has a structure supported by the pair of flow velocity detecting portion support portions 32 at the central portion of the substrate main portion 31b. In order to form such a structure, it is formed by cutting a plate-like substrate with NCM or the like as in the case of the second embodiment.

In this embodiment, the shape of the substrate main portion 31b is formed in the shape of a circular belt-shaped outer peripheral portion. However, the shape of the belt-shaped outer peripheral portion constituting the substrate main portion 31b is not limited to this. The substrate portion 31a may be formed on the inner portion of the belt-shaped outer peripheral portion constituting the substrate main portion 31b or in the center portion, and may be in a polygonal shape. Any structure supported by 32 may be used.
In this embodiment, there are two flow velocity detection unit instruction units, but one may be used if strength is obtained, and three or more may be used if there is no problem in performance.

A circuit pattern (not shown) for the flow velocity detection unit is formed at the mounting location of the flow velocity detection unit 30 of the substrate portion 31a, and the heater element 4 is mounted on one surface by soldering. The temperature measuring element 3 is mounted by soldering on the other surface of the substrate portion 31a so as to face the portion. Therefore, the heater element 4 and the temperature measuring element 3 have a structure in which both sides (front surface and back surface) of the substrate portion 31a are thermally connected directly via the mounting portion of the substrate portion 31a.
Instead of mounting the temperature measuring element 3 and the heater element 4 on both surfaces (front surface and back surface) of the substrate portion 31a, both elements 3 and 4 are disposed on one surface of the substrate portion 31a as described in the second embodiment. You may make it become the structure directly connected thermally by arrange | positioning adjacent and mutually mounting.

  Further, the flow velocity detection unit 30 has a structure that is supported by a pair of flow velocity detection unit support portions 32 integrally extending from the substrate main portion 31b at the central portion of the belt-shaped outer peripheral portion. A space 33 is formed around the periphery. Reference numeral 34 denotes a through hole to which a signal line for supplying power to the heater element 4 and outputting temperature measurement value data of the temperature measuring element 3 is connected. Since it is configured in this manner, the same effects as those of the first and second embodiments are obtained.

  A fourth embodiment of the present invention will be described in detail with reference to FIGS. FIG. 4 is a schematic view of the essential portions showing a fourth embodiment of the present invention. In addition, about the same part as the 1st-3rd Example, the same name and the same number are used and the description is abbreviate | omitted.

  In this embodiment, the purpose is to reduce the conduction of heat from the flow velocity detection unit 40 that affects the air temperature measurement unit 44. As shown in FIG. An elongated flow velocity detection portion support portion 42 and an air temperature measurement portion support portion 43 that are integrally extended from the substrate main portion 41b are formed apart from each other. A substrate portion 41a for mounting the flow velocity detection unit 40 supported by the flow velocity detection unit support portion 42 is formed at the distal end portion of the flow velocity detection portion support portion 42, and the distal end of the temperature measurement portion support portion 43 is formed. The board portion 41c on which the temperature measuring unit 44 supported by the temperature measuring unit support unit 43 is mounted is formed using NCM or the like, as in the second embodiment.

  A circuit pattern (not shown) for a flow velocity detection unit (not shown) and a circuit pattern for temperature measurement (not shown) are respectively provided on the surfaces of the substrate portion 41a on which the flow velocity detection unit 40 is mounted and the substrate portion 41c on which the temperature measurement unit 44 is mounted. ) Is formed. A temperature measuring element 3 that is a general-purpose surface-mounting component and a heater element 4 that is a general-purpose surface-mounting component are each mounted by soldering on a surface-mounted portion of the substrate portion 41a to constitute a flow velocity detection unit 40. A temperature measuring element 45, which is a general-purpose surface-mounted component, is mounted by soldering on the surface mounting portion of the portion 41c to constitute the temperature measuring unit 44.

Accordingly, the flow velocity detection unit 40 has a structure that is integrally supported by the substrate main portion 41b by the flow velocity detection portion support portion 42, and the air temperature measurement portion 44 has the substrate main portion 41b by the air temperature measurement portion support portion 43. It is a structure that is supported in a single piece. Further, the temperature measuring element 3 and the heater element 4 are mounted on the surface of the substrate portion 41a, and the elements 3 and 4 are disposed adjacent to each other and mounted so as to be thermally connected directly. It has become.
Instead of arranging and mounting the temperature measuring element 3 and the heater element 4 adjacent to each other, as described in the first embodiment, the temperature measuring element 3 and the heater element 4 are respectively mounted on the front surface and the back surface of the substrate portion 41a. It may be made to be a structure directly connected through the heat.

  Furthermore, a space 46 is provided around each of the flow velocity detection unit 40 and the air temperature measurement unit 44, and a space 47 is also provided between the flow velocity detection unit 40 and the air temperature measurement unit 44. And it has the structure which provided the plate-shaped board | substrate principal part. Reference numeral 48 denotes an attachment hole for attaching the thermal flow rate / flow rate sensor to another device.

  Since it is configured in this way, the same effects as in the first to third embodiments can be obtained, and the heat conduction from the flow velocity detection unit 40 to the substrate main part 41c can be reduced. Furthermore, the heat conduction can be further reduced by forming the support portion 42 for the flow velocity detection portion to be thin. A space 47 is formed between the flow velocity detection unit 40 and the air temperature measurement unit 44, and a space 46 is also formed around the flow velocity detection unit 40 and the air temperature measurement unit 44. The main part of the substrate is provided. In addition, by forming the temperature measurement unit support 43 of the temperature measurement unit 44 to be thin, the heat conduction to the temperature measurement unit 44 can be further reduced, and the heat from the flow velocity detection unit 40 is measured by the temperature measurement. The influence on the portion 44 can be reduced as much as possible.

  FIG. 5 shows a modified example of the thermal flow rate / flow rate sensor shown in FIG. 4. The flow rate detection unit 40 ′ is disposed so as to sandwich the temperature measuring element 3 and the temperature measuring element 3. The two heater elements 4 are provided. Since it is configured in this manner, even when the temperature of the temperature measuring element 3 is lowered, the temperature of the temperature measuring element 3 is more quickly arranged by the heater elements 4 arranged so as to sandwich the temperature measuring element 3 and the number of the temperature measuring elements 3 is increased. Therefore, the responsiveness as a thermal flow rate / flow rate sensor can be improved. Further, by mounting a heater element on the opposite surface of the substrate, characteristics such as responsiveness can be further improved.

  In general, in a thermal flow rate / flow rate sensor, a flow rate detection unit in which a temperature measuring element and a heater element are mounted and an air temperature measurement unit in which an air temperature measurement element for measuring temperature is mounted are arranged on the same substrate. In this case, the influence of the heat conduction from the heater element of the flow velocity detection unit on the temperature measurement unit becomes a problem. Therefore, in order to see this effect, the inventor, as shown in FIG. 6, the flow velocity detection unit 40A and the temperature measurement on the same substrate (the substrate main part 41b has a rectangular belt-shaped outer periphery). A prototype A having a structure in which the portion 44A is arranged was created.

  Next, in Example 4 described above, the thermal flow velocity / flow rate sensor having the structure shown in FIG. 4 is used as a basic structure, the shape of the substrate portion 41a for detecting the flow velocity, the flow velocity detection portion support portion 42, and the temperature measurement portion support portion 43. Prototypes (prototypes B, C, D, and E) with various lengths and the like were created and compared with prototype A. The results are shown in FIGS.

  The results of the heat conduction comparison experiments shown in FIGS. 6 to 10 show that the ambient temperature of the thermal flow rate / flow rate sensor is 0 [° C.] and the heat at the time of 120 [s] has elapsed since the thermal flow rate / flow rate sensor was turned on. This shows the temperature distribution in the flow velocity / flow rate sensor. In these results, in particular, the higher the temperature in the air temperature measurement unit, that is, the larger the temperature difference from the air temperature measurement unit with respect to the ambient temperature 0 [° C.], the more the temperature measurement unit due to heat conduction from the heater element of the flow velocity detection unit. It shows that the influence of.

  First, in the case of the prototype A shown in FIG. 6, the influence on the temperature measurement unit 44 </ b> A due to heat conduction from the heater element of the flow velocity detection unit 40 </ b> A was measured. As a result, as shown in FIG. 6, there is an influence of heat conduction of air temperature +15 [° C.] or more, and in a low wind speed or no wind state, after several minutes, it corresponds to several [m / s] even though there is no wind. Measurement error occurred, which was a practical problem.

  Next, in the case of the prototype B shown in FIG. 7, as apparent from the temperature distribution shown in FIG. 7, there is almost no influence on the temperature measuring unit 44B due to the heat conduction from the heater element of the flow velocity detecting unit 40B. As a result, there was no problem in practical use. Reference numeral 42B denotes a flow velocity detection unit support, and 43B denotes an air temperature measurement unit support.

  The prototype C shown in FIG. 8 has a structure in which the interval (space 47C) between the flow velocity detection unit support 42C and the temperature measurement unit support 43C is wider than that of the prototype B. As is apparent from the temperature distribution shown in FIG. 8, it has been found that the space 47C between the flow velocity detection portion support portion 42C and the temperature measurement portion support portion 43C does not affect the heat conduction.

  The prototype D shown in FIG. 9 has a structure in which the area of the substrate main part 41cD is reduced compared to the prototype B. As is clear from the temperature distribution shown in FIG. 9, it has been found that the effect of heat conduction increases when the area of the substrate main portion 41cD is reduced. In addition, 40D is a flow velocity detection unit, 42D is a flow velocity detection unit support unit, 43D is an air temperature measurement unit support unit, and 44D is an air temperature measurement unit.

  In the prototype E shown in FIG. 10, when the lengths of the flow rate detection unit support 42E and the temperature measurement unit support 43E are shortened, in particular, when the length of the flow rate detection unit support 42E is shortened, The impact was found to be significant. In addition, 41cE is a board | substrate main part, 40E is a flow velocity detection part, 44E is an air temperature measurement part.

  From the above experimental results, the prototype B and the prototype C described in Example 4 have almost no influence on the temperature measurement unit 44B due to the heat conduction from the heater element of the flow velocity detection unit 40B, and there is no problem in practical use. The result was obtained.

  A fifth embodiment of the present invention will be described in detail with reference to FIG. FIG. 11 is a schematic view of the essential portions showing a fifth embodiment of the present invention. In addition, about the same part as 1st Example-4th Example, the same name and the same number are used and the description is abbreviate | omitted.

  The fifth embodiment aims to lower the heat conduction from the flow velocity detection unit 50 that affects the air temperature measurement unit 54 and to protect the flow velocity detection unit 50.

  As shown in FIG. 11, an arch-shaped strip-shaped outer peripheral portion 51d extending integrally from the substrate main portion 51b of the single plate-like substrate 51 is formed, and the substrate main portion 51b of the plate-like substrate 51 is formed. At the center of one end, an elongated flow velocity detecting portion support portion 52 that is integrally extended from the substrate main portion 51b is formed. A substrate portion 51 a on which the flow velocity detection unit 50 supported by the flow velocity detection portion support 52 is mounted is formed at the tip of the flow velocity detection portion support portion 52. At this time, the length of the flow velocity detecting portion support portion 52 is adjusted so that the substrate portion 51a of the flow velocity detecting portion 50 is positioned at the center portion of the belt-shaped outer peripheral portion 51d. Therefore, the arch-shaped belt-shaped outer peripheral portion 51d serves as a guard portion 56 that protects the flow velocity detection portion 50 having a structure protruding from the substrate main portion 51b.

The heater element 4 and the temperature measuring element 3 are each mounted by soldering at the surface mounting location of the substrate portion 51a to constitute the flow velocity detection unit 50. Therefore, the temperature measuring element 3 and the heater element 4 are surface-mounted on the substrate portion 51a, and the elements 3 and 4 are disposed and mounted adjacent to each other so as to be thermally connected directly. It has become.
Instead of arranging and mounting the temperature measuring element 3 and the heater element 4 adjacent to each other, as described in the first embodiment, the temperature measuring element 3 and the heater element 4 are respectively mounted on the front surface and the back surface of the substrate portion 51a. It may be made to be a structure directly connected through the heat.

  Further, the periphery of the flow velocity detection unit 50 and the flow velocity detection unit support unit 52 is formed using an NCM or the like in a state where the arch-shaped belt-like outer peripheral portion 51d extending from the substrate main portion 51b of the substrate 51 is left. Is formed.

  Accordingly, since the space 57 is formed around the flow velocity detection unit 50 and the flow velocity detection unit support unit 52 that supports the flow velocity detection unit 50, the flow velocity detection unit 50 is supported by the flow velocity detection unit support unit 52. It is in a state of protruding from the substrate main part 51b.

  Reference numeral 54 denotes an air temperature measurement unit, which is provided on an arch-shaped belt-shaped outer peripheral portion 51d formed to extend to the substrate main portion 51b. An air temperature measuring element 55 is mounted on the surface mounting portion of the substrate portion 51c of the air temperature measuring unit 54 by soldering. Reference numeral 48 denotes an attachment hole for attaching the thermal flow rate / flow rate sensor to another device.

  Since it is configured in this way, the same effects as those of the first to fourth embodiments are obtained, and the guard portion 56 protrudes from the substrate main portion 51b via the flow velocity detection portion support portion 52. It is possible to protect the existing flow velocity detection unit 50. Furthermore, the guard part 56 can also prevent burns caused by erroneous contact with the heater element 4 that generates heat in the flow velocity detection part 50. Further, since the guard portion 56 can be integrally formed with the substrate by NCM or the like at the substrate manufacturing stage, manufacturing and assembly costs can be greatly reduced.

  It can be placed in each room in the building and used as part of the comfort sensor. There are PMV (predicted average thermal sensation), ET (effective temperature), OT (working temperature), etc. as comfort evaluation indexes of human living environment, all of which are calculated using the value of wind speed. Temperature sensors and humidity sensors are becoming popular in ordinary households, but fans have been used as a method for maintaining comfort in summer since ancient times, and it is known that the wind is effective in maintaining and improving comfort. ing. This is because by removing the air staying layer and the boundary layer formed on the body surface of the living body by the air flow by the wind, the evaporation of the skin surface is promoted and the skin can obtain a cooling effect.

  However, wind speed sensors have never been used in devices such as air conditioners and electric fans. Since the present invention can provide a flow rate / flow rate sensor with improved cost, durability, ease of manufacture, etc., there is a possibility of introduction into a living environment that has not been introduced in the past.

  Similarly, it can be expected to be applied to the monitoring of human living environment and surrounding environment, such as inspection of ventilation function in buildings, inspection and monitoring of labor environment standards, and inspection and monitoring of smoke distribution based on the Health Promotion Law.

  On the other hand, in medical institutions such as hospitals, it is known that the surrounding environment of patients affects the recovery of treatment for patients, and temperature and humidity have been actively managed from the past. In addition, patients who have undergone surgery, immediately after surgery, or patients who have undergone modulation of the bioregulatory function, need to pay more attention to environmental management than patients in other conditions because the body temperature regulation function is reduced. is there. Furthermore, the post-operative course of a surgical patient is particularly required to minimize environmental stress on the patient during and after surgery. However, the air velocity, which is one of the evaluation factors of comfort, has not been actively used until now. In Japan's medical environment where the number of beds is decreasing, early discharge due to short-term recovery of patients will benefit patients who are burdened with medical institutions and are forced to wait for hospitalization. Therefore, introduction into the medical field can be expected.

  In the industrial field, it can be applied to inspection of wind speed and air volume in a clean air environment. In clean rooms and chambers where only the inside of a box-like structure can be made into a clean air environment, attention must be paid to the mixing and mixing of contaminated air, but conventionally the wind speed and volume could not be monitored. Moreover, in the field of agriculture, especially in the field of horticulture, it has been found that applying a breeze of 0.3 to 0.7 m / s to plants or plant communities is effective in promoting photosynthesis and preventing disease. Therefore, it is expected to be used for monitoring clean air environment and plant production management.

1, 21, 31, 41, 51 Plate-like substrates 1a, 21a, 31a, 41a, 51a forming flow velocity / flow rate sensors Substrate portions 1b, 21b, 31b of the flow velocity detectors 5, 20, 30, 40, 50 41b, 51b Substrate main part 3 Heater element 4 Temperature measuring element 5, 20, 30, 40, 50 Flow rate detection part 9, 22, 32, 42, 52 Flow rate detection part support part 34, 44, 54 Air temperature measurement part 33, 43 Air temperature measuring unit support part 35, 45, 55 Air temperature measuring element 36, 37, 38, 47, 57 Space 41c, 51c Substrate portion of the air temperature measuring part 44, 54 56 Guard part

Claims (4)

A thermal type that measures the flow velocity and flow rate of a fluid comprising a heater element that generates heat by a supply current and a temperature measuring element that detects a temperature of heat from the heater element that changes according to the flow rate. In the manufacturing method of the flow velocity / flow rate sensor,
The heater element and the temperature measuring element are general-purpose surface mount components,
From the plate-like single substrate of the thermal flow rate / flow rate sensor, a belt-like outer peripheral portion constituting the substrate main portion which is the main portion of this substrate is formed integrally with the substrate,
A pair of elongated flow velocity detection portion support portions integrally extending in the center direction from the substrate main portion constituting the belt-shaped outer peripheral portion, and the tip portions of the pair of flow velocity detection portion support portions are supported on the tip portions. A substrate part on which the flow velocity detection unit is mounted is formed integrally with the substrate main part,
Forming a circuit pattern for the flow velocity detection unit on a substrate portion on which the flow velocity detection unit is mounted;
The heater element is mounted on one surface of the surface mounting portion of the substrate portion on which the flow velocity detection unit is mounted,
The temperature measuring element is mounted on the other surface of the surface mounting portion of the substrate portion on which the flow velocity detection unit is mounted, facing the surface mounting portion of the heater element,
The heater element and the temperature measuring element are arranged and mounted on both surfaces of the surface mounting portion of the substrate portion on which the flow velocity detection unit is mounted, so that the heater element and the temperature measuring device are interposed via the substrate portion at the surface mounting location. Forming the flow velocity detection part formed by thermal direct connection with the element;
The surface mounting location of the substrate portion for mounting the flow velocity detection portion, the pair of flow velocity detection portion support portions extending integrally from the surface mounting location to the main portion of the substrate, and the belt-shaped outer peripheral portion, By cutting the periphery of the substrate,
Using a general-purpose substrate manufacturing apparatus so that the substrate main portion constituting the belt-shaped outer peripheral portion is a guard portion that protects the flow velocity detection portion, and a space is provided around the flow velocity detection portion. A method of manufacturing a thermal flow rate / flow rate sensor characterized by being formed. A flow rate detector having a heater element that generates heat by a supply current, a temperature measuring element that detects the temperature of heat from the heater element that changes according to the flow rate, and an air temperature that includes an air temperature measuring element that measures the air temperature In the manufacturing method of the thermal flow rate / flow rate sensor that measures the flow rate and flow rate of the fluid consisting of the measurement unit,
The heater element, the temperature measuring element, and the temperature measuring element are general-purpose surface-mount components,
From the plate-like single substrate of the thermal flow rate / flow rate sensor, a belt-like outer peripheral portion constituting the substrate main portion which is the main portion of this substrate is formed integrally with the substrate,
An elongated flow rate detecting portion supporting portion integrally extending from the main portion of the substrate is integrally formed with the substrate at a central portion of one end of the substrate,
A circuit board portion for mounting the flow velocity detection unit is formed at the distal end of the flow velocity detection unit so that the substrate portion is located at the center of the belt-shaped outer periphery, and the circuit pattern for the flow velocity detection unit is formed on the substrate portion. Form the
Forming a circuit pattern for the air temperature measurement section on the belt-shaped outer periphery;
The heater element and the temperature measuring element are thermally directly connected to each other by mounting the heater element and the temperature measuring element adjacent to each other on the surface mounting portion of the substrate portion on which the flow velocity detection unit is mounted. Forming the flow velocity detection unit connected,
Forming the temperature measuring part formed by mounting the temperature measuring element on the surface mounting location of the belt-shaped outer peripheral part,
The substrate, leaving the surface mounting portion of the substrate portion on which the flow velocity detecting portion is mounted, the flow velocity detecting portion supporting portion integrally extending from the surface mounting portion to the main portion of the substrate, and the belt-shaped outer peripheral portion. By cutting the periphery of
The flow velocity detection part formed at the surface mounting location is formed in a structure that is supported by the substrate main part by the flow rate detection part support part, and the substrate main part constituting the belt-shaped outer peripheral part is formed by the flow velocity detection. And a space around the flow rate detection unit and the temperature measurement element, a space is provided between the flow rate detection unit and the temperature measurement element, and a plate-like shape is provided. A method of manufacturing a thermal flow rate / flow rate sensor, characterized in that it is formed using a general-purpose substrate manufacturing apparatus so as to have a structure in which a main part of the substrate is provided. A thermal type that measures the flow velocity and flow rate of a fluid comprising a heater element that generates heat by a supply current and a temperature measuring element that detects a temperature of heat from the heater element that changes according to the flow rate. In the flow velocity / flow rate sensor,
A plate-like single substrate of the thermal flow rate / flow rate sensor;
A belt-shaped outer peripheral portion constituting a main part of the substrate which is a main part of the substrate integrally formed from the substrate;
A pair of elongated flow velocity detection unit support portions integrally extending in the center direction from the substrate main portion constituting the belt-shaped outer peripheral portion;
A substrate portion for mounting the flow velocity detection portion formed integrally with the substrate main portion while being supported at the tip of the pair of flow velocity detection portion support portions,
A circuit pattern for the flow velocity detection unit formed on the substrate part,
A heater element that is a general-purpose surface-mounted component mounted on one surface of a surface-mounted portion of a substrate portion on which the flow velocity detection unit is mounted;
A temperature measuring element that is a general-purpose surface-mounted component mounted on the other surface of the surface-mounted portion of the substrate portion that mounts the flow velocity detection unit positioned opposite to the surface-mounted portion of the heater element;
The heater element and the temperature measuring element are arranged and mounted on both surfaces of the surface mounting portion of the substrate portion on which the flow velocity detection unit is mounted, so that the heater element and the temperature measuring device are interposed via the substrate portion at the surface mounting location. It consists of the flow velocity detection part formed by thermally connecting the element directly,
The surface mounting location of the substrate portion for mounting the flow velocity detection portion, the pair of flow velocity detection portion support portions extending integrally from the surface mounting location to the main portion of the substrate, and the belt-shaped outer peripheral portion, By cutting the periphery of the substrate,
Using a general-purpose substrate manufacturing apparatus so that the substrate main portion constituting the belt-shaped outer peripheral portion is a guard portion that protects the flow velocity detection portion, and a space is provided around the flow velocity detection portion. A thermal flow rate / flow rate sensor characterized by being formed. A flow rate detector having a heater element that generates heat by a supply current, a temperature measuring element that detects the temperature of heat from the heater element that changes according to the flow rate, and an air temperature that includes an air temperature measuring element that measures the air temperature In the thermal flow rate / flow rate sensor that measures the flow rate and flow rate of the fluid consisting of the measurement unit,
A plate-like single substrate of the thermal flow rate / flow rate sensor;
A belt-shaped outer peripheral portion constituting a main part of the substrate which is a main part of the substrate integrally formed from the substrate;
In the central part of one end of the substrate, the support for the flow rate detection unit formed in an elongated shape integrally formed with the substrate and extending integrally from the main part of the substrate,
A substrate portion for mounting the flow velocity detection portion formed at the front end portion of the flow velocity detection portion support portion and formed so as to be positioned at the center portion of the belt-shaped outer peripheral portion,
A circuit pattern for the flow velocity detection unit formed on the substrate part,
A circuit pattern for the air temperature measurement part formed on the belt-shaped outer peripheral part;
By forming a heater element, which is a general-purpose surface-mounted component, and a temperature-measuring element, which is a general-purpose surface-mounted component, arranged adjacent to each other and mounted on a surface-mounted portion of the substrate portion on which the flow velocity detection unit is mounted The flow rate detection unit formed by thermally connecting the heater element and the temperature measuring element directly;
The temperature measuring element which is a general-purpose surface-mounted component mounted on the surface-mounted portion of the belt-shaped outer peripheral portion,
The substrate, leaving the surface mounting portion of the substrate portion on which the flow velocity detecting portion is mounted, the flow velocity detecting portion supporting portion integrally extending from the surface mounting portion to the main portion of the substrate, and the belt-shaped outer peripheral portion. By cutting the periphery of
The flow velocity detection part formed at the surface mounting location is formed in a structure that is supported by the substrate main part by the flow rate detection part support part, and the substrate main part constituting the belt-shaped outer peripheral part is formed by the flow velocity detection. And a space around the flow rate detection unit and the temperature measurement element, a space is provided between the flow rate detection unit and the temperature measurement element, and a plate-like shape is provided. A thermal flow rate / flow rate sensor formed using a general-purpose substrate manufacturing equipment so as to have a structure in which the main part of the substrate is provided.