JP6884671B2 - Tire pressure detector - Google Patents

Description

The present invention relates to a tire pressure detecting device.

In recent years, a tire pressure monitoring system (Tire Pressure Monitoring System, abbreviated as TPMS) for monitoring the tire pressure of an automobile has become widespread.
As a tire pressure detection device applied as a detection unit of the system, there is one having a structure in which a pressure sensor is arranged in a chamber into which a fluid in the tire is introduced and sealed.
In Patent Document 1, the chamber in which the pressure sensor is arranged is composed of a cylindrical housing having a male screw formed on the outer circumference and a cap having a dome shape and a flange around the lower end opening, and the end surface of the housing. Disclosed is a tire pressure detection device having a structure in which an O-ring is pressed and sealed by aligning the end face of the cap with an O-ring via an O-ring and screwing and fastening a nut that engages with the flange of the cap to the housing. ..

European Patent Application Publication No. 2977234

It is desired to improve the pressure resistance of the tire pressure detection device provided with the sealing structure of the chamber in which the pressure sensor as described above is arranged.
In the invention described in Patent Document 1, when the tire pressure is applied in the chamber, the cap is pushed in the direction away from the housing, the force for pressing the O-ring is reduced, and the airtightness may be broken. Further, the loosening of the nut and the housing increases the risk of breaking the airtightness.

The present invention has been devised in view of the above conventional problems, and an object of the present invention is to improve the pressure resistance of a chamber in which a pressure sensor is arranged in a tire pressure detecting device.

The tire pressure detection device of the present invention has a chamber having both ends of an opening as an inlet for fluid in the tire and an opening at the other end facing the same, and the inside of the chamber communicating with the one end opening. A pressure sensor arranged in a chamber provided in the chamber, a sensor substrate on which the mounting surface on which the pressure sensor is mounted faces the chamber, and a sensor substrate arranged between the chamber and the other end opening, and the sensor substrate. A seal arranged in the internal space of the housing between the other end opening and the inner peripheral surface of the housing surrounding the internal space and adherently bonded to the opposite surface of the mounting surface of the sensor substrate. A stop resin is provided, and the other end opening side of the chamber is sealed by the sealing resin, and further adhered to the peripheral portion of the chamber and the peripheral edge portion of the mounting surface on the inner surface of the housing. A concave curved surface having a bonded resin and having a surface exposed to the chamber of the resin connecting the peripheral portion and the peripheral portion and drawing a concave curve in a cross-sectional view passing through the central portion of the chamber perpendicular to the sensor substrate. characterized in that there.

The tire pressure detecting device of the present invention is preferably characterized in that at least a part of the concave curve traced from the peripheral edge portion is arranged so as to recede in the outer edge direction of the sensor substrate.

The tire pressure detecting device of the present invention is preferably characterized in that the concave curve is arranged so as to uniformly recede in the outer edge direction of the sensor substrate from the peripheral portion to the peripheral portion.

The tire pressure detection device of the present invention is preferably characterized in that a shelf surface facing the mounting surface is formed on the peripheral portion, and the resin is adherently bonded to the shelf surface. To do.

The tire pressure detecting device of the present invention is preferably characterized in that the resin is adherently bonded to the inner edge of the shelf surface.

The tire pressure detecting device of the present invention is preferably characterized in that a peripheral groove is formed on the shelf surface, and a part of the resin is filled in the peripheral groove.

According to the present invention, the pressure resistance of the chamber in which the pressure sensor is arranged in the tire pressure detecting device is improved.

It is a perspective view which shows the tire pressure detection device which concerns on 1st Embodiment of this invention. It is a perspective view which shows the tire pressure detection device which concerns on 1st Embodiment of this invention, and is cut out about 120 about the central axis. It is a partially enlarged view of FIG. It is an exploded perspective view which shows the tire pressure detection device which concerns on 1st Embodiment of this invention. It is a front view which shows the tire pressure detection device which concerns on 1st Embodiment of this invention, and is cut about 120 about the central axis. It is a perspective view which shows the tire pressure detection device which concerns on 1st Embodiment of this invention, and is the figure which shows the housing part which cut out about 90 about the central axis. It is a partial vertical sectional view which shows the model M1 which concerns on a simulation. It is a partial vertical sectional view which shows the model M2 which concerns on a simulation. It is a partial vertical sectional view which shows the model M3 which concerns on a simulation. It is a perspective view which shows the model M3 which concerns on a simulation, and is the figure (a) which shows the housing part cut out about 90 about the central axis, and is the part enlarged view (b). It is a table which described the partial vertical cross-sectional view of 7 models M3-M9 which concerns on simulation. It is the graph which compared the stress about 9 models M1-M9 which concerns on a simulation. It is a vertical sectional view which shows the tire pressure detection device which concerns on 2nd Embodiment of this invention.

An embodiment of the present invention will be described below with reference to the drawings. The following is an embodiment of the present invention and does not limit the present invention.

[First Embodiment]
First, the structure of the tire pressure detecting device according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 6.
1 to 6 show a valve cap type tire pressure detecting device 1A.
The tire pressure detection device 1A includes a housing 10, a pressure sensor 20, a sensor substrate 21, a sealing resin 30, a second substrate 40, a conductor pin 41, a transmission antenna 43, a cap 44, and a valve release. 50, a valve gasket 51, a valve coupler 52, and a reinforcing resin 60 are provided.
The housing 10 is formed in a tubular shape with both ends open. One end opening 11a of the housing 10 is an inlet for fluid in the tire. A chamber 12 is provided in the housing 10 so as to communicate with the opening 11a at one end. A pressure sensor 20 is arranged in the chamber 12. The pressure sensor 20 detects the tire pressure by communicating the inside of the tire with the chamber 12 through the opening 11a at one end.
The sealing resin 30 is arranged in the internal space 13 of the housing between the pressure sensor 20 and the other end opening 11b of the housing 10. Since the sealing resin 30 is adherently bonded to the inner peripheral surface 13a of the housing 10 surrounding the internal space 13 over the entire circumference, the sealing resin 30 seals the other end opening 11b side of the chamber 12. ing.
In addition, in the terms "tire pressure detector" and "tire pressure", the term "air" is used only as a general term, and the present invention is filled in the tire. It is intended to detect the pressure of the gas being used, and is not intended to be limited to those intended only for air.

The surface 31 of the sealing resin 30 facing the other end opening 11b is in contact with the inner peripheral surface 13a of the housing 10 at the peripheral edge. The peripheral edge of the surface 31 forms a fillet 31a. The flat central surface 31b of the surface 31 is recessed inward from the other end opening 11b, and the concave curved surface rising from the central surface 31b toward the peripheral edge is the fillet 31a.

The sensor substrate 21 on which the pressure sensor 20 is mounted is arranged between the internal space 13 in which the sealing resin 30 is arranged and the chamber 12.
The mounting surface 21a on which the pressure sensor 20 of the sensor substrate 21 is mounted faces the chamber 12, and the sealing resin 30 is adherently bonded to the opposite surface 21b of the mounting surface 21a.
It can be manufactured by arranging the sensor substrate 21 so as to partition the internal space 13 in which the sealing resin 30 is arranged and the chamber 12, and filling the sealing resin 30 from the other end opening 11b.

For example, an aluminum alloy is used as the material of the housing. It is preferable that the difference between the coefficient of thermal expansion of the material used for the housing 10 and the coefficient of thermal expansion of the sealing resin 30 and the reinforcing resin 60 is small.
When metal is used as the material of the housing 10, it is preferable that a corrosion-resistant film such as an alumite film is formed.
The openings 11a and 11b of the housing 10 may have the same diameter or different diameters. In the present embodiment, the opening 11a for introducing air is small, and the opening 11b sealed with the sealing resin 30 is large.

According to the tire pressure detection device 1A having the structure shown in FIGS. 1 to 6 above, a sealing resin (epoxy or the like) having higher heat resistance than rubber packing or the like can be selected, and the sealing resin 30 can be selected. Since the thickness of the rubber can be increased, the sealing property can be improved.
Further, the fillet 31a relaxes the thermal stress generated between the sealing resin 30 and the housing 10. Since the fillet 31a is formed, that is, the sealing resin 30 is not fully filled up to the opening 11b of the housing 10, the sealing resin 30 is thin on the central surface 31b, and the whole is thin on average, and the thermal stress is high. It can be kept small.
Even if the sealing resin 30 is thinned on the central surface 31b to reduce the thermal stress, the fillet 31a is formed on the peripheral edge, so that the inner peripheral surface 13a of the housing 10 and the sealing resin 30 are joined. Since the transverse length of the surface from the chamber 12 side to the opening 11b side is lengthened, breakage of the sealing structure at the joint surface can be suppressed.
Since the fillet 31a is formed on the opening 11b side of the housing 10, the housing 10 can be made thinner.

A recess 14b is formed on the inner peripheral surface 13a, and the sealing resin 30 has entered the recess 14b. Instead of the concave portion 14b, a convex portion that penetrates into the sealing resin 30 may be used. The concave portion 14b or the convex portion in place of the concave portion 14b may be formed over one circumference of the inner peripheral surface 13a, or may be formed in a plurality of rows intermittently.
By forming the concave portion 14b or a convex portion in place of the concave portion 14b on the inner peripheral surface 13a, the sealing resin 30 enters the concave portion 14b, or the convex portion enters the sealing resin 30 and seals with the inner peripheral surface 13a of the housing 10. By increasing the bonding area with the stop resin 30, the bonding force between the housing 10 and the sealing resin 30 is further improved by the anchor effect due to the penetration.
Further, since the interface between the sealing resin 30 and the inner peripheral surface 13a is bent, it is difficult for the sealing resin 30 to peel off from the inner peripheral surface 13a. In particular, according to the concave portion 14b or the convex portion which is continuous around the circumference, even if peeling or cracking occurs at any position in the circumferential direction, there is an effect of uniformly suppressing the growth.

Both the concave portion 14b and the convex portion may be formed on the inner peripheral surface 13a. The concave portions and the convex portions that are intermittent in the circumferential direction may be arranged by switching in the circumferential direction, or may be arranged in a plurality of rows apart from each other in the central axis C direction.
A plurality of concave portions 14b or convex portions that are continuous around the circumference may be arranged in the central axis C direction. In the present embodiment, a plurality of recesses 14b that are continuous around the circumference are arranged in the central axis C direction.

A peripheral groove 15 for holding the O-ring is formed on the outer periphery of the housing 10. This is to improve the sealing property inside the cap 44 and protect the internal second substrate 40, the coin battery 42, and the like.

The temperature sensor 22 is mounted on the sensor substrate 21 and arranged in the chamber 12 in the same manner as the pressure sensor 20.
Hereinafter, the other end opening 11b side of the housing 10 will be described as the upper side as appropriate.
The second substrate 40 is connected to the sensor substrate 21 via the conductor pin 41 and is arranged above the sealing resin 30. A coin battery 42 as a power source is held on the second substrate 40, and a transmitting antenna 43 for transmitting the detection signals of the pressure sensor 20 and the temperature sensor 22 is mounted on the second substrate 40.
The cap 44 is screwed and connected to the upper end of the housing 10 to cover the housing 10.
At the lower end of the housing 10, the valve release 50, the valve gasket 51, and the valve coupler 52 are connected to the opening 11a in this order.
The valve coupler 52 is provided with a female screw of the same standard as the valve cap of the tire. By screwing and connecting the valve coupler 52 to the valve of the tire, the valve release 50 pushes and releases the valve core, and the tire pressure is increased. The detection device 1A is connected to the valve of the tire. As a result, the inside of the tire and the chamber 12 communicate with each other, so that the tire pressure can be detected by the pressure sensor 20 and the tire air temperature can be detected by the temperature sensor.

(Reinforcing resin)
As shown in FIG. 3, the reinforcing resin 60 is adherently bonded to the peripheral portion 61 of the chamber 12 on the inner surface of the housing 10 and the peripheral portion 62 of the mounting surface 21a.
Each part of the housing 10 such as the chamber 12 is formed around the central axis C passing through the centers of the openings 11a and 11b at both ends of the housing 10, and parts such as the sensor substrate 21 are installed in the housing 10.
The mounting surface 21a including the peripheral edge portion 62 is perpendicular to the central axis C. The peripheral portion 61 forms a slope (inner tapered surface) obliquely downward from the portion 63 in contact with the peripheral edge portion 62 and toward the central axis C. The peripheral portion 61 and the side surface of the chamber 12 below the reinforcing resin 60 are continuous slopes (inner tapered surfaces).
The reinforcing resin 60 is filled so as to fill the outer peripheral portion of the space below the mounting surface 21a of the sensor substrate 21 in the internal space of the housing 10, and the reinforcing resin 60 is hung from the peripheral portion 61 to the peripheral portion 62. It is continuously adherently joined. The portion 63 in contact between the peripheral portion 61 and the peripheral portion 62 extends around the central axis C. The reinforcing resin 60 is also formed around the central axis C over one circumference, and is adherently bonded to the peripheral portion 61 and the peripheral portion 62 over one circumference.

As shown in FIG. 6, a first shelf surface 16a on which the sensor substrate 21 is placed is formed inside the housing 10. The first shelf surface 16a is a surface perpendicular to the central axis C and facing the other end opening 11b direction. The inner peripheral edge of the first shelf surface 16a corresponds to a portion 63 where the peripheral portion 61 and the peripheral edge portion 62 are in contact with each other.

(simulation)
Here, a simulation for comparing and verifying the effect of the reinforcing resin 60 on improving the pressure resistance is disclosed.
In the simulation, the structure forming the chamber 12 consisting of the housing 10 of the tire pressure detection device 1A, the sensor substrate 21, and the sealing resin 30 was used as the basic model for calculation, and the stress and deformation were calculated by setting the inside of the chamber 12 to a high pressure. It is a thing. The following nine models M1-M9 were used as specific calculation targets having different structures with respect to the reinforcing resin 60. Differences in the structure of models M1-M3 and simulation results are as shown in FIGS. 7 to 9.

The model M1 shown in FIG. 7 is a model to which the reinforcing resin 60 is not applied, and as shown in FIG. 7, the sensor substrate 21 and the sealing resin 30 are greatly bent.
The model M2 shown in FIG. 8 is provided with the reinforcing resin 60 and is the same as that shown in FIG. In the model M2, as shown in FIG. 8, the bending of the sensor substrate 21 and the sealing resin 30 was reduced by the action of the reinforcing resin 60.
In the model M3 shown in FIGS. 9 and 10, the reinforcing resin 60 is applied, and the peripheral portion 61 is formed with the second shelf surface 16b facing the mounting surface 21a, and further, the second shelf surface 16b is formed. A peripheral groove 17 is formed on the shelf surface 16b.
The reinforcing resin 60 is adherently bonded to the second shelf surface 16b, a part of which is filled in the peripheral groove 17, and is adhered to the inner edge 18 of the second shelf surface 16b.
In the model M3, as shown in FIG. 9, the bending of the sensor substrate 21 and the sealing resin 30 was effectively suppressed by the action of the reinforcing resin 60, and the bending was almost eliminated.

The table shown in FIG. 11 shows a schematic cross-sectional view centered on the reinforcing resin 60 of the models M3-M9.
In the model M4-M9, the structure of the housing 10 is the same as that of the model M3, and only the shape of the reinforcing resin 60 is different.
In each of the models M4-M9, the bending of the sensor substrate 21 and the sealing resin 30 was effectively suppressed to the same level as that of the model M3 (FIG. 9), and the bending was almost eliminated.

What is common to the models M3-M9 is that the surface exposed to the chamber 12 of the reinforcing resin 60 connecting the peripheral portion 61 and the peripheral portion 62 is a concave curved surface that draws a concave curve 60a in the cross-sectional view shown in FIG. That is.
What is common to models M3 and M7-M9, which does not hold for models M4-M6, is that at least a part of the concave curve 60a traced from the peripheral edge 62 is arranged so as to recede toward the outer edge of the sensor substrate 21. That is what has been done. In the models M4-M6, the concave curve 60a is a uniform change that approaches the center of the chamber 12 when traced from the peripheral edge 62.

The fact that only the model M3 is established is that the concave curve 60a is arranged so as to uniformly recede in the outer edge direction of the sensor substrate 21 from the peripheral portion 62 (mounting surface 21a) to the peripheral portion 61 (second shelf surface 16b). That is what you are doing. "Uniformly retreating" means that the change is never changed as it approaches the center of the chamber 12. When the concave curve 60a of the model M3 is traced from the peripheral portion 61 (second shelf surface 16b), it uniformly approaches the center of the chamber 12, that is, the reinforcing resin 60 uniformly extends to the central portion of the sensor substrate 21. I will go.
On the other hand, in the model M7-M9, when the concave curve 60a is traced from the peripheral portion 62 (mounting surface 21a) to the peripheral portion 61 (second shelf surface 16b), it approaches the center of the chamber 12 from the retreat. Turn to change. It is the same even if it traces from the peripheral part 61.
In the model M3, the position where the concave curve 60a is in contact with the peripheral portion 61 (second shelf surface 16b) is closer to the central axis C than the position where the concave curve 60a is in contact with the peripheral portion 62 (mounting surface 21a).
In comparison with this, in the model M7-M9, the position where the concave curve 60a is in contact with the peripheral portion 61 (second shelf surface 16b) and the position where the concave curve 60a is in contact with the peripheral portion 62 (mounting surface 21a) are in the radial direction (center). There is not much change in the direction perpendicular to the axis C). Therefore, the radius of curvature of the concave curve 60a is smaller than that of the model M3.

FIG. 12 shows a graph comparing stresses for models M1-M9. The stress generated for the model M1 was set to 100%.
The stress in the model M2 is smaller than the stress in the model M1, and the stress in the model M3 is smaller than the stress in the model M2. Consistent with the reduction in deformation described above. In the model M1, the sealing resin 30 and the sensor substrate 21 are greatly bent, and relatively high stress is generated not only in the sealing resin 30 and the sensor substrate 21 but also in the housing 10, and the housing 10 and the sealing resin 30 Stress concentration occurred at the joint of. On the other hand, in the model M2-M3, the stress was reduced as a whole, and the stress concentration portion was also moved to the inner edge of the joint between the reinforcing resin 60 and the sensor substrate, and the stress was significantly reduced especially in the model M3.
The stress in the model M4-M6 was smaller than the stress in the model M1, but was comparable to the stress in the model M2. It is considered that the cause is that the mounting surface 21a of the reinforcing resin 60 does not extend toward the central portion.
On the other hand, the stress in the model M7-M9 in which the mounting surface 21a of the reinforcing resin 60 was extended toward the central portion was larger than the stress in the model M3 in which the same elongation was larger, but was reduced by the stress in the model M2.

From the above simulation results, it was confirmed that by providing the reinforcing resin 60, deformation and stress generated in the member are reduced, and stress concentration in the joint portion between the housing 10 and the sealing resin 30 can be avoided. As a result, the airtight destruction of the chamber 12 due to peeling or breakage of the sealing resin 30 can be withstood up to a higher pressure. That is, the pressure resistance of the chamber in which the pressure sensor is arranged in the tire pressure detecting device is improved.
Even when the reinforcing resin 60 is provided, the concave curve 60a described above is formed, and in particular, a part traced from at least the peripheral edge 62 of the concave curve 60a as in the models M3 and M7-M9 is the outer edge of the sensor substrate 21. The pressure resistance can be improved by arranging so as to recede in the direction.
Further, as in the model M3, the concave curve 60a is arranged so as to uniformly recede in the outer edge direction of the sensor substrate 21 from the peripheral portion 62 (mounting surface 21a) to the peripheral portion 61 (second shelf surface 16b). As a result, the radius of curvature of the concave curve 60a becomes large, so that the withstand voltage can be further improved.
Further, by providing the second shelf surface 16b, it is easy to hold a necessary and sufficient amount of resin at a position appropriately close to the mounting surface 21a, and it is easy to form a concave curve 60a having the above-mentioned advantageous configuration. At this time, when the reinforcing resin 60 is adherently bonded to the inner edge 18 of the second shelf surface 16b, the amount of resin bonded to the peripheral edge portion 62 of the mounting surface 21a can be increased, thereby reducing stress. You can also do it. Further, by providing the peripheral groove 17, it becomes easy to hold the resin. In the present embodiment, the number of peripheral grooves 17 is one, but it may be provided in double or triple or more.

(Production method)
Next, the manufacturing method will be described.
The method of assembling the tire pressure detection device 1A is not particularly limited, but the following two examples can be mentioned.

(Assembly example 1)
Each component is mounted on the sensor board 21 and the second board 40. At that time, the conductor pin 41 is mounted on the sensor substrate 21.
On the other hand, the resin constituting the reinforcing resin 60 is applied to the inside of the housing 10. If the amount of resin applied is small, the concave curve 60a is drawn toward the outer edge of the sensor substrate 21. The same applies to the case where the applied resin flows and the amount of resin in the portion constituting the reinforcing resin 60 is reduced. If there is a second shelf surface 16b, resin is applied on the second shelf surface 16b. Due to the presence of the second shelf surface 16b, it is difficult for the resin to flow. Further, the peripheral groove 17 is provided on the second shelf surface 16b, and it is difficult for the resin to flow from the second shelf surface 16b.
Next, the sensor board 21 is installed in the housing 10. At this time, the resin constituting the reinforcing resin 60 adheres to the mounting surface 21a. When there is a second shelf surface 16b, the resin sufficiently held on the second shelf surface 16b adheres to the mounting surface 21a, and the above-mentioned concave curve 60a is formed. In order to increase the elongation of the mounting surface 21a of the reinforcing resin 60 toward the central portion, the wettability of the resin with respect to the mounting surface 21a is selected in advance. It is also effective to install the sensor substrate 21 in the housing 10 and then hold the sensor substrate 21 with the other end opening 11b side down for a predetermined time. Before the next step, the resin constituting the reinforcing resin 60 may be semi-cured or completely cured. It is also possible to take a method of semi-curing or completely curing the resin constituting the reinforcing resin 60 as it is after holding the other end opening 11b side down for a predetermined time.

Next, the resin constituting the sealing resin 30 is injected into the internal space 13 of the housing 10.
Next, the resin constituting the reinforcing resin 60 and the resin constituting the sealing resin 30 are cured. When an epoxy resin is applied, it is cured by performing a heat treatment at 80 ° C. to 180 ° C.
The second substrate 40 is arranged above the sealing resin 30, and the conductor pin 41 protruding from the surface 31 of the sealing resin 30 and the electrode on the second substrate 40 are soldered.
Next, the coin battery 42 is inserted, and finally the cap 44 is attached.

(Assembly example 2)
A hole for resin injection is formed in the second substrate 40. Each component is mounted on the sensor board 21 and the second board 40, and both boards 20 and 40 are connected by conductor pins 41 for modularization.
On the other hand, the resin constituting the reinforcing resin 60 is applied to the inside of the housing 10. If the amount of resin applied is small, the concave curve 60a is drawn toward the outer edge of the sensor substrate 21. The same applies to the case where the applied resin flows and the amount of resin in the portion constituting the reinforcing resin 60 is reduced. If there is a second shelf surface 16b, resin is applied on the second shelf surface 16b. Due to the presence of the second shelf surface 16b, it is difficult for the resin to flow. Further, the peripheral groove 17 is provided on the second shelf surface 16b, and it is difficult for the resin to flow from the second shelf surface 16b.
Next, the modules of both boards 20 and 40 are installed in the housing 10. At this time, the resin constituting the reinforcing resin 60 adheres to the mounting surface 21a. When there is a second shelf surface 16b, the resin sufficiently held on the second shelf surface 16b adheres to the mounting surface 21a, and the above-mentioned concave curve 60a is formed. In order to increase the elongation of the mounting surface 21a of the reinforcing resin 60 toward the central portion, the wettability of the resin with respect to the mounting surface 21a is selected in advance. It is also effective to install the sensor substrate 21 in the housing 10 and then hold the sensor substrate 21 with the other end opening 11b side down for a predetermined time. Before the next step, the resin constituting the reinforcing resin 60 may be semi-cured or completely cured. It is also possible to take a method of semi-curing or completely curing the resin constituting the reinforcing resin 60 as it is after holding the other end opening 11b side down for a predetermined time.

Next, the resin constituting the sealing resin 30 is injected into the internal space 13 of the housing 10 through the resin injection hole. For example, the needle of the injector is inserted into the hole for injecting the resin to inject the resin.
Next, the resin constituting the reinforcing resin 60 and the resin constituting the sealing resin 30 are cured. When an epoxy resin is applied, it is cured by performing a heat treatment at 80 ° C. to 180 ° C. Since the second substrate 40 has already been installed, it is possible to fill the periphery of the second substrate 40 with resin and cure it at the same time as the reinforcing resin 60 and the sealing resin 30.
Next, the coin battery 42 is inserted, and finally the cap 44 is attached.

[Second Embodiment]
In the first embodiment, the opening 11a for introducing air is small and the opening 11b sealed with the sealing resin 30 is large. However, as shown in FIG. 13, the housing 10B having the same diameter as the opening 11a and the opening 11b is provided. It is also possible to adopt it.
Even in this case, the second shelf surface 16b can be formed by providing the flange 19 facing inward in the housing 10B, and the peripheral groove 17 can be formed on the second shelf surface 16b.

As described above, the tire pressure detection device of the present embodiment has high pressure resistance so that the chamber in which the pressure sensor is arranged can withstand high pressure.

1A, 1B Tire pressure detection device 10 Housing 11a One end opening (air introduction port)
11b Another end opening 12 Chamber 13 Internal space 13a Inner peripheral surface 20 Pressure sensor 21 Sensor substrate 30 Encapsulating resin 60 Reinforcing resin

Claims (6)

A housing with both ends having an opening at one end, which is used as an inlet for fluid in the tire, and an opening at the other end facing the opening.
A pressure sensor that communicates with the one-end opening and is arranged in a chamber provided in the housing.
A mounting surface on which the pressure sensor is mounted faces the chamber, and a sensor substrate arranged between the chamber and the other end opening,
It is arranged in the internal space of the housing between the sensor board and the other end opening, and adheres to the inner peripheral surface of the housing surrounding the internal space and the opposite surface of the mounting surface of the sensor board. Equipped with a bonded sealing resin,
The sealing resin seals the other end opening side of the chamber.
Further, a resin adherently bonded to the peripheral portion of the chamber on the inner surface of the housing and the peripheral portion of the mounting surface is provided .
The surface of the resin that connects the peripheral portion and the peripheral portion and is exposed to the chamber is a concave curved surface that is perpendicular to the sensor substrate and draws a concave curve in a cross-sectional view passing through the central portion of the chamber. Tire pressure detector. The part traced from at least the peripheral portion of the concave curves, the tire air pressure detecting device according to claim 1, characterized in that it is arranged to retract the outer direction of the sensor substrate. The tire pressure detecting device according to claim 1 , wherein the concave curve is arranged so as to uniformly retract from the peripheral portion to the peripheral portion in the outer edge direction of the sensor substrate. A shelf surface facing the mounting surface is formed on the peripheral portion.
The tire pressure detecting device according to any one of claims 1 to 3 , wherein the resin is adherently bonded to the shelf surface. The tire pressure detecting device according to claim 4 , wherein the resin is adherently bonded to the inner edge of the shelf surface. A peripheral groove is formed on the shelf surface.
The tire pressure detecting device according to claim 4 or 5 , wherein a part of the resin is filled in the peripheral groove.

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