Ultrasonic sensor device

Abstract

An ultrasonic sensor device includes an outer shell, a piezoelectric component, a plate body and a plurality of fixing parts. The outer shell includes a coupling plate which is a metal plate and a bearing shell which is a plastic part. The coupling plate has an opening. The bearing shell includes a bottom wall which is opposite to the opening and a surrounding side wall which surrounds and is connected to the bottom wall in an integral manner and the outer edge of the coupling plate covers a part of the coupling plate. The piezoelectric component includes a packaging body and a piezoelectric sheet which is at least partially covered by the packaging body. The packaging body is arranged on the bottom wall and surrounded by the surrounding side wall. The piezoelectric sheet has a sensing surface which is exposed to the packaging body and faces the bottom wall. The plate body is arranged on the coupling plate of the outer shell and has a pressing surface which faces the packaging body and the coupling plate. A plurality of fixing parts are used to fix the plate body to the coupling plate of the outer shell.

Description

Technical Field

[0001] The present invention relates to a sensor device, in particular to an ultrasonic sensor device with a piezoelectric component. Background Art

[0002] Diesel engines need to be equipped with a selective catalytic reduction (SCR) system to reduce the emission of toxic nitrogen-hydrogen compounds (NOx). The catalytic reduction system is to add urea to diesel to neutralize the toxic nitrogen-hydrogen compounds, so that the toxic nitrogen-hydrogen compounds are converted into water and nitrogen. When the urea concentration in the diesel is not enough, the diesel engine may emit too much nitrogen-hydrogen compounds.

[0003] Urea used in diesel engines is mixed with water and stored in a storage tank adjacent to the diesel engine. Usually, a plurality of ultrasonic sensors are arranged next to the storage tank to detect the urea concentration or liquid level of the fluid in the storage tank.

[0004] The conventional ultrasonic sensor device mainly includes an outer shell and a piezoelectric sheet placed in the outer shell. In order to make the piezoelectric sheet fit the sensing surface in the outer shell, a packaging colloid must be poured into the outer shell after the piezoelectric sheet is placed in the outer shell.

[0005] However, the adhesive force of the encapsulating colloid is sometimes unable to make the piezoelectric sheet closely adhere to the sensing surface, so that the ultrasonic sensor device in the conventional technology has reliability problems.

[0006] Furthermore, the process of pouring the encapsulating colloid into the outer shell often cannot accurately control the amount of the colloid material, resulting in material waste. In addition, it is also difficult to perform quality control or rework on the piezoelectric sheet and the colloid in the outer shell.

[0007] In addition, the material of the outer shell can be metal or plastic. When the outer shell is made of metal, the resonance effect between the outer shell and the piezoelectric piece is poor. However, if the outer shell is made of plastic, there is a problem of insufficient strength. Summary of the invention

[0008] The invention provides an ultrasonic sensor device with high reliability.

[0009] The invention provides an ultrasonic sensor device having good resonance characteristics.

[0010] The ultrasonic sensing device provided by the present invention includes an outer shell, a piezoelectric component, a plate body and a plurality of fixing parts. The outer shell includes a coupling plate which is a metal plate and a bearing shell which is a plastic part. The coupling plate has an opening. The bearing shell includes a bottom wall which is relatively provided with the opening and a surrounding side wall which surrounds and is connected to the bottom wall in an integral manner and the outer edge of the coupling plate covers a part of the coupling plate. The piezoelectric component includes a packaging body and a piezoelectric sheet which is at least partially covered by the packaging body. The packaging body is arranged on the bottom wall and surrounded by the surrounding side wall. The piezoelectric sheet has a sensing surface which is exposed to the packaging body and faces the bottom wall. The plate body is arranged on the coupling plate of the outer shell and has a pressing surface which faces the packaging body and the coupling plate. The plurality of fixing parts are used to fix the plate body to the coupling plate of the outer shell so that the plate body applies pressure to the packaging body of the piezoelectric component, thereby pressing the sensing surface of the piezoelectric sheet down to the bottom wall.

[0011] The ultrasonic sensing device provided by the present invention includes an outer shell, a bearing shell, a piezoelectric component, a plate body and a plurality of fixing parts. The outer shell is a metal part and includes an integrally formed bonding plate, a bottom wall and a first surrounding side wall, the bonding plate has an opening arranged relative to the bottom wall, and the surrounding side wall is connected between the bottom wall and the inner edge of the surrounding side wall. The bearing shell is a plastic part and includes a second surrounding side wall that covers a part of the bonding plate from the outer edge of the bonding plate, the second surrounding side wall extends in a direction away from the bottom wall, and has an opening at one end away from the bottom wall, wherein the bonding plate is located between the opening and the bottom wall. The piezoelectric component includes a packaging body and a piezoelectric sheet at least partially covered by the packaging body, the packaging body is arranged on the bottom wall and surrounded by the surrounding side wall, and the piezoelectric sheet has a sensing surface exposed to the packaging body and facing the bottom wall. The plate body is arranged on the bonding plate of the outer shell and has a pressing surface facing the packaging body and the bonding plate. A plurality of fixing members are used to fix the plate body to the combining plate of the outer shell cover, so that the plate body applies pressure to the packaging body of the piezoelectric component, thereby pressing the sensing surface of the piezoelectric sheet down to the bottom wall.

[0012] In one embodiment of the present invention, the board is a circuit board.

[0013] In one embodiment of the present invention, the piezoelectric component further includes a positive guide pin having one end connected to the piezoelectric sheet and a negative guide pin having one end connected to the piezoelectric sheet, the positive guide pin and the negative guide pin pass through the packaging body, and the plate body has two openings for the positive guide pin and the negative guide pin to pass through.

[0014] In one embodiment of the present invention, the package body is adhered to the surrounding sidewalls.

[0015] In one embodiment of the present invention, the package body has a surrounding shape conforming to the surrounding sidewall.

[0016] In one embodiment of the present invention, the piezoelectric component further includes a matching layer or a conductive layer disposed on the sensing surface of the piezoelectric sheet and corresponding to the vibration energy of the piezoelectric sheet.

[0017] In an embodiment of the present invention, each fixing member is a screw, the plate body has a plurality of through holes, and the combining plate has a plurality of screw holes.

[0018] In one embodiment of the present invention, the surrounding side wall extends further away from the bottom wall and has an opening at one end away from the bottom wall. The combining plate is located between the opening of the surrounding side wall and the bottom wall. The ultrasonic sensor device further includes a cover body that closes the opening of the surrounding side wall.

[0019] In one embodiment of the present invention, the package body includes a matching layer and / or an absorption layer corresponding to the vibration energy of the piezoelectric piece.

[0020] In one embodiment of the present invention, the outer shell is a metal piece, and the carrying shell is a plastic piece.

[0021] The ultrasonic sensor device in the embodiment of the present invention applies pressure to the packaging body by a plate body, thereby pressing the piezoelectric sheet down to the bottom wall of the outer shell cover. Compared with the piezoelectric sheet in the conventional technology that is only connected to the outer shell cover by a colloid, the piezoelectric sheet in the embodiment of the present invention can be more tightly arranged on the bottom wall of the outer shell cover, thereby having higher reliability.

[0022] The connecting plate for fixing the plate body of the ultrasonic sensor device of the embodiment of the present invention is made of metal and has higher durability, while the bottom wall supporting the piezoelectric component and the surrounding side wall surrounding the piezoelectric component are made of plastic and have better resonance characteristics, so as to solve the problem that the ultrasonic sensor device of the conventional technology is difficult to take into account both structural strength and resonance characteristics.

[0023] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1A FIG. 4 is a schematic diagram of an explosion of an ultrasonic sensor device according to an embodiment of the present invention.

[0025] Figure 1B FIG. 4 is a cross-sectional schematic diagram of an ultrasonic sensor device according to an embodiment of the present invention.

[0026] Figure 1C FIG. 4 is a schematic diagram of a plate according to another embodiment of the present invention.

[0027] Figure 2 FIG. 4 is a cross-sectional schematic diagram of an ultrasonic sensor device according to another embodiment of the present invention.

[0028] Figure 3FIG. 4 is a cross-sectional schematic diagram of an ultrasonic sensor device according to another embodiment of the present invention. DETAILED DESCRIPTION

[0029] Figure 1A is a schematic diagram of an explosion of an ultrasonic sensor device according to an embodiment of the present invention, Figure 1B FIG. 1 is a cross-sectional schematic diagram of an ultrasonic sensor device according to an embodiment of the present invention. Figure 1A and Figure 1B The ultrasonic sensor device 100 of this embodiment includes an outer shell 110, a piezoelectric component 120, a plate 130 and a plurality of fixing members 140. The outer shell 110 includes a coupling plate 111 which is a metal plate and a carrying shell 112 which is a plastic part. The coupling plate 111 has an opening 1110, and the carrying shell 112 includes a bottom wall 1121 which is relatively arranged at the opening 1110 and a surrounding side wall 1122 which surrounds and is connected to the bottom wall 1121 in an integral manner. The surrounding side wall 1122 covers a part of the coupling plate 111 by the outer edge of the coupling plate 111. The piezoelectric component 120 includes a packaging body 121 and a piezoelectric sheet 122 which is at least partially covered by the packaging body 121. The packaging body 121 is disposed on the bottom wall 1121 and surrounded by the surrounding side wall 1122. The piezoelectric sheet 122 has a sensing surface 1221 which is exposed to the packaging body 121 and faces the bottom wall 1121. The plate 130 is disposed on the coupling plate 111 of the outer shell 110 and has a pressing surface 131 facing the package body 121 and the coupling plate 111. A plurality of fixing members 140 are used to fix the plate 130 to the coupling plate 111 of the outer shell 110, so that the plate 130 applies pressure to the package body 121 of the piezoelectric component 120, thereby pressing the sensing surface 1221 of the piezoelectric sheet 122 downwardly against the bottom wall 1121.

[0030] The outer shell cover of the ultrasonic sensor device 100 of the present embodiment can be made, for example, by insert molding. The outer edge of the combining plate 111 can be placed in a plastic molding cavity (not shown) corresponding to the supporting shell 112, and then the fluid plastic is injected into the cavity. After the plastic is cooled and removed from the cavity, the outer shell cover 110 of the ultrasonic sensor device 100 is completed.

[0031] In this embodiment, the material of the connecting wall 111 may be metal such as stainless steel, aluminum alloy or other alloys, but is not limited thereto. The material of the bearing shell 112 may be an insulating material such as polyamide (PA), polyethylene (PE) or polypropylene (PP).

[0032] In the present embodiment, the surrounding side wall 1122 further extends in a direction away from the bottom wall 1121 and has an opening 1123 at one end away from the bottom wall 1121. Specifically, the surrounding side wall 1122 and the bottom wall 1121 form a receiving space S, and the combining plate 111 is located between the opening 1123 of the surrounding side wall 1122 and the bottom wall 1121, and is located in the receiving space S. The ultrasonic sensor device 100 may further include a cover 150 that closes the opening 1123 of the surrounding side wall 1122.

[0033] In this embodiment, the plate 130 may include a plate of a single material or a plate of a composite material. In this embodiment, the plate 130 may be a circuit board. For example, the plate 130 may further have a setting surface 132 opposite to the pressing surface 131. The plate 130 may be provided with a connector 133 on the setting surface 132 to electrically connect to the piezoelectric sheet 122 or to an external device (not shown).

[0034] In this embodiment, the plate body 130 is in the shape of a flat plate, but is not limited thereto. Figure 1C The plate 130a is shown as being bent. One side of the plate 130a has a concave portion 134, and the other side has a corresponding convex portion 135. When the package body 121 protrudes from the opening 1110 of the connecting plate 111, it can abut against the concave portion 134, while when the package body 121 is recessed in the opening 1110 of the connecting plate 111, it can abut against the convex portion 135.

[0035] In this embodiment, the package body 121 of the piezoelectric component 120 has a surrounding shape conforming to the surrounding sidewall 113, for example Figure 1A The package body 121 and the surrounding sidewall 113 may also be in other conformal shapes, such as polygons. The package body 121 may include a matching layer and / or an absorption layer corresponding to the vibration energy of the piezoelectric piece, and the material may include epoxy resin (Epoxy), silicon oxide (SiOx) or other colloids.

[0036] In this embodiment, the piezoelectric component 120 further includes an adhesive layer 125 disposed on the sensing surface 1221 of the piezoelectric sheet 122 and corresponding to the piezoelectric sheet 122 , which may be a matching layer or a conductive layer corresponding to the vibration energy of the piezoelectric sheet 122 .

[0037] In this embodiment, the piezoelectric component 120 further includes a positive electrode guide pin 123 connected to the piezoelectric sheet 122 at one end and a negative electrode guide pin 124 connected to the piezoelectric sheet 122 at one end, the positive electrode guide pin 123 and the negative electrode guide pin 124 pass through the package body 121, and the plate body 130 has a through hole 137 and a through hole 138 for the positive electrode guide pin 123 and the negative electrode guide pin 124 to pass through respectively. The positive electrode guide pin 123 and the negative electrode guide pin 124 can be connected to an external power supply device (not shown).

[0038] In this embodiment, each fixing member 140 is a screw, and the plate 130 has a plurality of through holes 136, and the coupling plate 111 of the outer shell 110 has a plurality of screw holes 1111. By locking these fixing members 140 to the screw holes 1111, the plate 130 is fixed to the coupling plate 111 and pressure is applied to the packaging body 121. The number of fixing members 140 is at least three to balance the downward pressure of the plate 130.

[0039] The ultrasonic sensor device 100 of this embodiment can be placed in liquid, for example, it can be matched with a waveguide (not shown) to sense the height of the liquid, or it can be arranged opposite to a reflector (not shown) to sense the concentration of the liquid.

[0040] Regarding the method for manufacturing the piezoelectric component 120 of the present embodiment, the piezoelectric sheet 122 can be preliminarily combined with the packaging body 121 in a mold (not shown), or the piezoelectric sheet 122 can be placed on the bottom wall 1121 of the supporting shell 112, and then the liquid packaging colloid 121 is poured into it through the opening 1110 set in the combining plate 111, and then solidified in the space formed by the surrounding side walls 1122, the bottom wall 1121 and the combining plate 111.

[0041] The ultrasonic sensor device 100 of this embodiment applies pressure to the packaging body 121 with the plate body 130, so that the piezoelectric sheet 122 can abut against the bottom wall 111 of the outer shell cover 110. Compared with the piezoelectric sheet in the conventional technology that is only connected to the outer shell cover by colloid, the piezoelectric sheet 122 in the embodiment of the present invention can fit more closely to the bottom wall 111 of the outer shell cover 110, thereby having better reliability.

[0042] The connecting plate 111 for fixing the plate body 130 of the ultrasonic sensing device 100 of the present embodiment is made of metal and has higher durability, while the bottom wall 1121 supporting the piezoelectric component 120 and the surrounding side wall 1122 surrounding the piezoelectric component 120 are made of plastic and have better resonance characteristics, thereby solving the problem that the ultrasonic sensing device of the conventional technology is difficult to balance the structural strength and resonance characteristics.

[0043] Figure 2 This is a cross-sectional schematic diagram of an ultrasonic sensor device according to another embodiment of the present invention. Figure 2 The ultrasonic sensor device 100a of this embodiment includes an outer shell 110a, a bearing shell 160, a piezoelectric assembly 120, a plate 130, and a plurality of fixing members 140. The outer shell 110a is a metal member and includes an integrally formed connecting plate 111a, a bottom wall 114, and a first surrounding side wall 115. The connecting plate 111a has an opening 1110 disposed relative to the bottom wall 114, and the first surrounding side wall 115 is connected between the bottom wall 114 and the connecting plate 111a.

[0044] The carrying case 160 is a plastic part and includes a second surrounding side wall 162, which is formed by the outer edge of the connecting plate 111a and covers a part of the connecting plate 111a. The second surrounding side wall 162 extends in a direction away from the bottom wall 114 and has an opening 161 at one end away from the bottom wall 114, wherein the connecting plate 111a is located between the opening 161 and the bottom wall 114. Similar to the above-mentioned embodiment, the connecting plate 111a of the outer shell 110a can be connected to the carrying case 160 by, for example, insert molding.

[0045] The structures and functions of the piezoelectric component 120, the plate 130 and the fixing member 140 of the ultrasonic sensor device 100a of this embodiment are the same as those of Figure 1A The ultrasonic sensor device 100 will not be described here.

[0046] The ultrasonic sensor device 100a of this embodiment is Figure 1A The difference of the ultrasonic sensor device 100 is: Figure 1A In the ultrasonic sensor device 100 of the embodiment, only the connecting wall 111 is made of metal, while the ultrasonic sensor device 100a of this embodiment includes the connecting wall 111a, the bottom wall 114 and the outer shell 110a surrounding the side wall 115, which are made of metal and are integrally formed. Figure 1A The ultrasonic sensor device 100 of this embodiment can have better resonance characteristics, and the ultrasonic sensor device 100a of this embodiment can have better durability. Users can use different ultrasonic sensors according to different usage requirements or environments. Figure 1A The ultrasonic sensing device 100 or the ultrasonic sensing device 100a of the present embodiment.

[0047] Figure 3 This is an exploded schematic diagram of an ultrasonic sensor device according to another embodiment of the present invention. Figure 3 The ultrasonic sensor device 100c of this embodiment is Figure 1A The ultrasonic sensor device 100c of the present embodiment is substantially the same as the ultrasonic sensor device 100 of the present embodiment, except that the ultrasonic sensor device 100c of the present embodiment further includes a reflector 170 and a plurality of connecting rods 180. The reflector 170 is disposed opposite to the carrying shell 112 of the outer shell 110, and the connecting rods 180 are connected between the reflector 170 and the carrying shell 112. The reflector 170 can be used to reflect the vibration signal of the piezoelectric component 120 to detect the concentration of the liquid. On the other hand, the present embodiment can also be applied to Figure 2 Ultrasonic sensing device 100a.

[0048] The ultrasonic sensor device in the embodiment of the present invention applies pressure to the packaging body by a plate body, thereby pressing the piezoelectric sheet down to the bottom wall of the outer shell cover. Compared with the piezoelectric sheet in the conventional technology that is only connected to the outer shell cover by a colloid, the piezoelectric sheet in the embodiment of the present invention can be more tightly arranged on the bottom wall of the outer shell cover, thereby having higher reliability.

[0049] The connecting plate for fixing the plate body of the ultrasonic sensor device of the embodiment of the present invention is made of metal and has higher durability, while the bottom wall supporting the piezoelectric component and the surrounding side wall surrounding the piezoelectric component are made of plastic and have better resonance characteristics, so as to solve the problem that the ultrasonic sensor device of the conventional technology is difficult to take into account both structural strength and resonance characteristics.

[0050] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes by using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. An ultrasonic sensor device, characterized in that: include: An outer shell includes a connecting plate and a bearing shell, the connecting plate has an opening, the bearing shell includes a bottom wall opposite to the opening of the connecting plate and a surrounding side wall integrally formed and connected to the bottom wall, the surrounding side wall covers a part of the connecting plate by the outer edge of the connecting plate; A piezoelectric component, comprising a packaging body and a piezoelectric sheet at least a portion of which is covered by the packaging body, wherein the packaging body is disposed on the bottom wall of the carrying shell and surrounded by the surrounding side wall, and the piezoelectric sheet has a sensing surface exposed from the packaging body and facing the bottom wall; A plate body, disposed on the combining plate and having a pressing surface facing the packaging body and the combining plate; as well as A plurality of fixing members, used for fixing the plate body to the combining plate of the outer shell, so that the plate body applies pressure to the packaging body of the piezoelectric component, thereby pressing the sensing surface of the piezoelectric sheet downward to the bottom wall; The combining plate is a metal plate, and the bearing shell is a plastic part.

2. The ultrasonic sensor device according to claim 1, characterized in that: The board body is a circuit board.

3. The ultrasonic sensor device according to claim 1, characterized in that: The piezoelectric component further includes a positive guide pin with one end connected to the piezoelectric sheet and a negative guide pin with one end connected to the piezoelectric sheet. The positive guide pin and the negative guide pin pass through the packaging body, and the plate body has two openings for the positive guide pin and the negative guide pin to pass through.

4. The ultrasonic sensor device according to claim 1, characterized in that: The package body is adhered to the surrounding side wall.

5. The ultrasonic sensor device according to claim 1, characterized in that: The package body has a surrounding shape conforming to the surrounding sidewall.

6. The ultrasonic sensor device according to claim 1, characterized in that: The piezoelectric component further includes a matching layer or a conductive layer disposed on the sensing surface of the piezoelectric sheet and corresponding to the vibration energy of the piezoelectric sheet.

7. The ultrasonic sensor device according to claim 1, characterized in that: Each of the fixing members is a screw, the plate body has a plurality of through holes, and the combining plate has a plurality of screw holes.

8. The ultrasonic sensor device according to claim 1, characterized in that: The surrounding side wall further extends in a direction away from the bottom wall and has an opening at one end away from the bottom wall. The combining plate is located between the opening of the surrounding side wall and the bottom wall. The ultrasonic sensor device further includes a cover body that closes the opening.

9. The ultrasonic sensor device according to claim 1, characterized in that: The package body includes a matching layer and / or an absorption layer corresponding to the vibration energy of the piezoelectric piece.

10. An ultrasonic sensor device, characterized in that: include: An outer shell, comprising an integrally formed connecting plate, a bottom wall and a first surrounding side wall, wherein the first surrounding side wall is connected between the connecting plate and the bottom wall, and the connecting plate has an opening disposed opposite to the bottom wall; A bearing shell, comprising a second surrounding side wall, which is formed by the outer edge of the connecting plate of the outer shell to cover a part of the connecting plate, and extends in a direction away from the bottom wall, and has an opening at one end away from the bottom wall, and the connecting plate is located between the opening and the bottom wall; A piezoelectric component, comprising a packaging body and a piezoelectric sheet at least a portion of which is covered by the packaging body, wherein the packaging body is disposed on the bottom wall and surrounded by the first surrounding side wall, and the piezoelectric sheet has a sensing surface exposed from the packaging body and facing the bottom wall; A plate body, disposed on the combining plate of the outer shell and having a pressing surface facing the packaging body and the combining plate; as well as A plurality of fixing members, used for fixing the plate body to the combining plate of the outer shell, so that the plate body applies pressure to the packaging body of the piezoelectric component, thereby pressing the sensing surface of the piezoelectric sheet downward to the bottom wall; The outer shell is a metal part, and the supporting shell is a plastic part.

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