Ultrasonic sensor structure

Abstract

The utility model discloses an ultrasonic sensor structure, which comprises a shell and an end cover, an accommodating cavity is arranged in the shell and the end cover, a circuit board is mounted in the accommodating cavity, and one side of the circuit board is connected with a transducer assembly and a thermistor in a soldering manner. According to the utility model, the combined structure of the transducer assembly, the thermistor and the circuit board is embedded into the shell, the wiring harness assembly is matched with the sealing kit and the gland to be tightly pressed on the joint pipe, so that the sealing performance between the structures is realized, the circuit board and the shell are locked by the locking bolt, the stability of the structure is improved, and the shell and the end cover are combined and mounted, so that the sealing performance is improved. According to the utility model, the sealing assembly positions of the device adopt multiple sealing structures, so that the device has the advantages of high temperature resistance and corrosion resistance, the problem of sealing failure of the sensor in the long-time use process in a high-temperature urea environment is effectively prevented, and the service life of the sensor is prolonged. The service life of the device is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to sensor technical field especially an ultrasonic sensor structure. BACKGROUND

[0002] In the SCR aftertreatment system, the urea sensor is a link in the urea supply system, and the sensor urea concentration value is mainly calculated by the echo time of the ultrasonic sensor to obtain the corresponding urea solution concentration. Since urea is weakly alkaline, the sealing components of the ultrasonic sensor gradually leak due to aging in a long-time high-temperature environment; therefore, the ultrasonic sensor of the urea sensor needs to meet the use in a long-time high-temperature urea environment.

[0003] The conventional scheme adopts a sealing ring sealing structure, and the existing sealing ring will be aged and damaged in a long-time high-temperature urea soaking, thereby causing leakage failure. This leads to a short service life of the urea sensor and a safety hazard.

[0004] Therefore, it is necessary to develop an ultrasonic sensor structure. CONTENT OF THE UTILITY MODEL

[0005] The utility model solves the technical problem in the prior art, and provides an ultrasonic sensor structure. Through a new ultrasonic sensor structure design, the risk of leakage of the ultrasonic sensor in a long-time high-temperature urea environment is effectively solved. The ultrasonic sensor adopts various sealing structures, which effectively avoids the influence of urea on the service life of the ultrasonic sensor.

[0006] To solve the above technical problem, the utility model adopts the technical scheme of:

[0007] An ultrasonic sensor structure comprises a shell and an end cover, the shell and the end cover are internally provided with a containing cavity, a circuit board is installed in the containing cavity, a transducer assembly and a thermistor are tin soldered on one side of the circuit board, a joint pipe penetrating through the containing cavity is integrally arranged at the top of the shell, a sealing sleeve is detachably installed on the outer side of the joint pipe, a wire harness assembly is combined and installed at the connection end of the circuit board, the wire harness assembly is interference-fitted with the sealing sleeve on the outer side of the end portion, the outer diameter of the sealing sleeve is consistent with the inner diameter of the joint pipe, a gland is arranged on the outer side of the wire harness assembly and located at the top of the sealing sleeve, and the gland is detachably installed with the joint pipe.

[0008] Preferably, the access port of the circuit board is arranged opposite to the joint pipe, at least two limit grooves in annular array are arranged on the outer side of the circuit board, limit pegs corresponding to the limit grooves are integrally arranged on the inner wall of the shell, the circuit board is slidably connected with the limit pegs through the limit grooves, a threaded hole is arranged at the end portion of the limit peg, and a locking bolt for fixedly connecting the circuit board with the shell is screw-connected in the threaded hole.

[0009] Preferably, a recess is formed on the circuit board, a resistance mounting groove is mounted on the inner wall of the shell, and the power line of the thermistor is pressed into the recess and extends into the resistance mounting groove, and the resistance mounting groove is filled with heat-conducting glue.

[0010] Preferably, an annular groove is formed at one end of the shell, an annular platform is integrally arranged on one side of the end cover, and the annular platform is embedded and fitted inside the annular groove, and a polyurethane rubber ring is arranged inside the annular groove for bonding the shell and the end cover into an integrated structure.

[0011] Preferably, an annular platform is integrally arranged on one side of the end cover, and the annular platform is embedded and fitted in the shell, and the outer side wall of the connection between the shell and the end cover is welded, and the shell and the end cover are filled with a polyurethane glue layer between the inner wall of the end cover and the circuit board after being combined.

[0012] Preferably, positioning protrusions are fixedly connected to both sides of the end of the shell away from the end cover, clamping grooves are reserved between the two positioning protrusions, and a reflection support is clamped between the two clamping grooves for reflecting ultrasonic signals, and anti-bubble rubber sleeves are buckled to the outer sides of the two positioning protrusions, and the shell and the anti-bubble rubber sleeves are fixedly combined by straight rod bolts.

[0013] Preferably, the cross-sectional shape of the reflection support is U-shaped, the bottom plate of the reflection support is fitted to the inner wall of the anti-bubble rubber sleeve, the legs of the reflection support match the outer diameter of the clamping groove, the reflection support is nested inside the anti-bubble rubber sleeve, and the leg ends of the reflection support are sleeved on the straight rod bolts.

[0014] Preferably, oppositely arranged inner flow channel holes are pre-set between the two legs of the reflection support, and a plurality of symmetrically distributed outer flow channel holes are penetrated through the anti-bubble rubber sleeve for guiding fluid passing and bubble discharging.

[0015] Preferably, the side of the shell close to the positioning protrusion is provided with a transmitting / receiving plate, the bottom plate of the reflection support is arranged opposite to the transmitting / receiving plate, and the reflection support and the transmitting / receiving plate enclose a detection area.

[0016] Preferably, the wire harness assembly comprises a silica gel wire harness and a heat shrinkable sleeve, and the heat shrinkable sleeve is sleeved on the outside of the silica gel wire harness in a fitted manner.

[0017] The utility model has the following beneficial effects:

[0018] By embedding the combination structure of the transducer assembly, the thermistor and the circuit board into the shell, welding the wire harness assembly bottom end at the connecting end of the circuit board, pressing the sealing sleeve and the gland on the joint pipe, realizing the sealing between the structures, locking the circuit board and the shell with the locking bolt, improving the stability of the structure, combining and installing the shell and the end cover, and buffering and protecting the structures by the polyurethane rubber ring or the polyurethane rubber layer, the high sealing performance of the internal components is realized, the multiple sealing structures are used in the sealing assembly positions of the device, the advantages of high temperature resistance and corrosion resistance are achieved, the sealing failure problem of the sensor in the high temperature urea environment during long time use is effectively prevented, and the service life of the device is prolonged.

[0019] By installing the anti-bubble rubber sleeve at the rear end of the shell, cooperating with the internally installed reflection support, the reflection support and the transmitting / receiving plate surround the detection area, the transducer assembly transmits ultrasonic signals, passes through the fluid and is reflected back to the transmitting / receiving plate by the reflection support, the fluid is detected, the problem that bubbles enter the detection area to affect the urea concentration detection is solved, and the installation of the thermistor is designed to be bent at the groove and the probe end is immersed in the heat-conducting glue, and the sensing accuracy of the thermistor is improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The utility model provides an ultrasonic sensor structure perspective view is provided for the utility model;

[0021] Figure 2 The utility model provides an ultrasonic sensor structure first view angle explosion map is provided for the utility model;

[0022] Figure 3 The utility model provides an ultrasonic sensor structure second view angle explosion map is provided for the utility model;

[0023] Figure 4 The utility model provides an ultrasonic sensor structure's containing cavity internal structure display graph is provided for the utility model;

[0024] Figure 5 The utility model provides an ultrasonic sensor structure perspective view is provided for the utility model; Figure 4 The utility model provides an ultrasonic sensor structure perspective view is provided for the utility model;

[0025] Figure 6 The utility model provides another embodiment structure diagram of the shell and end cover connecting structure.

[0026] Among them:

[0027] Housing-1; end cover-2; circuit board-3; transducer assembly-4; thermistor-5; joint pipe-6; sealing kit-7; wiring harness assembly-8; gland-9; limiting groove-10; limiting pile-11; locking bolt-12; groove-13; resistance installation groove-14; annular groove-15; annular platform-16; polyurethane rubber ring-17; positioning protrusion-18; anti-bubble rubber sleeve-19; straight rod bolt-20; reflecting support-21; polyurethane adhesive layer-22. DETAILED DESCRIPTION

[0028] The utility model will be described in further detail below in combination with the drawings and specific preferred embodiments.

[0029] In the description of the utility model, it needs to be understood that the orientation or position relationship indicated by the terms "left side", "right side", "upper part", "lower part" and the like is the orientation or position relationship shown based on the drawings, and is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and "first", "second" and the like do not represent the importance of the parts, so it cannot be understood as a limitation on the utility model. The specific size adopted in the embodiment is only for the purpose of illustrating the technical scheme, and does not limit the protection scope of the utility model.

[0030] As shown in Figures 1-5 An ultrasonic sensor structure, comprising a housing 1 and an end cover 2, the housing 1 and the sensor end cover 2 are both made of high-temperature-resistant nylon material;

[0031] The housing 1 and the end cover 2 are internally provided with a containing cavity, the containing cavity is internally provided with a circuit board 3, one side of the circuit board 3 is tin soldered and connected with a transducer assembly 4 and a thermistor 5, the housing 1 is integrally provided with a joint pipe 6 penetrating through the containing cavity, the joint pipe 6 is externally detachably provided with a sealing kit 7, the circuit board 3 is combinationally provided with a wiring harness assembly 8 at the connection end, the internal circuit adopts a sealing structure, the wiring harness assembly comprises a silica gel wiring harness and a heat shrink sleeve, the heat shrink sleeve is in a form of a fitted sleeve externally provided on the silica gel wiring harness, so as to prevent the silica gel wiring harness from being scratched and damaged, and a high-temperature-resistant and corrosion-resistant silica gel material is selected for the external insulating layer of the silica gel wiring harness; the wiring harness assembly 8 is externally and tightly fitted with the sealing kit 7 at the end, the sealing kit 7 is provided in a form of a multiple-sealing rubber plug vulcanization structure, the outer diameter of the sealing kit 7 is consistent with the inner diameter of the joint pipe 6, the wiring harness assembly 8 is externally provided with a gland 9 at the top of the sealing kit 7, and the gland 9 is detachably connected with the joint pipe 6, such as threaded connection, or assembled by using a clamping structure.

[0032] The access port of the circuit board 3 is arranged opposite to the joint pipe 6, and at least two limit grooves 10 in annular array are arranged on the outer side of the circuit board 3, limit stakes 11 corresponding to the limit grooves 10 are arranged on the inner wall of the shell 1, and the circuit board 3 is slidably connected with the limit stakes 11 through the limit grooves 10, so that the circuit board 3 can be quickly positioned and installed, a threaded hole is arranged at the end of the limit stake 11, and a locking bolt 12 for fixing the circuit board 3 to the shell 1 is screwed in the threaded hole, so that the circuit board 3 is stable after installation and is not easy to be damaged.

[0033] Specifically, a groove 13 is arranged on the circuit board 3, a resistance mounting groove 14 is arranged on the inner wall of the shell 1, the power line of the thermistor 5 is pressed into the groove 13 and extends into the resistance mounting groove 14, and the resistance mounting groove 14 is filled with heat-conducting glue, so that the heat can be uniformly transmitted to the resistance mounting groove 14, and the sensing accuracy of the thermistor 5 is improved.

[0034] Specifically, a ring-shaped groove 15 is arranged at one end of the shell 1, a ring-shaped table plate 16 is integrally arranged on one side of the end cover 2, the ring-shaped table plate 16 is embedded in and fitted in the inside of the ring-shaped groove 15, and a polyurethane rubber ring 17 is arranged in the inside of the ring-shaped groove 15, so as to bond the shell 1 and the end cover 2 into an integrated structure, thereby facilitating quick butt joint installation, and the structure has high sealing performance, so as to ensure that the sensor works in a sealed environment and improve the safety of the equipment.

[0035] Specifically, positioning protrusions 18 are fixedly connected to both sides of the end of the shell 1 away from the end cover 2, and an anti-bubble rubber sleeve 19 is buckled and connected to the outer sides of the two positioning protrusions 18, the probe of the thermistor 5 extends into the resistance mounting groove 14 and is located on the inner side of the anti-bubble rubber sleeve 19, so as to improve the temperature detection accuracy, and the shell 1 and the anti-bubble rubber sleeve 19 are fixedly connected by a straight rod bolt 20.

[0036] Specifically, positioning protrusions 18 are fixedly connected to both sides of the end of the shell 1 away from the end cover 2, and a clamping groove is reserved between the two positioning protrusions 18, a reflection bracket 21 is clamped between the two clamping grooves, and the reflection bracket 21 is used for reflecting ultrasonic signals, an anti-bubble rubber sleeve 19 is buckled on the outer sides of the two positioning protrusions 18, and the shell 1 and the anti-bubble rubber sleeve 19 are fixedly connected by a straight rod bolt 20.

[0037] Specifically, opposite inner flow holes are arranged between the two legs of the reflection bracket 21, and a plurality of outer flow holes are arranged on the anti-bubble rubber sleeve 19, the outer flow holes are symmetrically arranged, and are used for guiding fluid to pass through and bubbles to be discharged.

[0038] Specifically, the side of the shell 1 close to the positioning protrusion 18 is provided as a transmitting / receiving plate, the bottom plate of the reflection bracket 21 is arranged opposite to the transmitting / receiving plate, and the reflection bracket 21 and the transmitting / receiving plate enclose a detection area.

[0039] As another connecting embodiment of the shell 1 and the end cover 2:

[0040] In order to improve the connecting strength of the shell 1 and the end cover 2, and improve the sealing effect of the accommodating cavity, as shown in the drawings, Figure 6 An annular table plate 16 is integrally arranged on one side of the end cover 2, and the annular table plate 16 is embedded and attached to the shell 1, the outer side wall of the connecting part of the shell 1 and the end cover 2 is welded, and the shell 1 and the end cover 2 are combined and located between the inner wall of the end cover 2 and the circuit board 3. A polyurethane glue layer 22 is filled.

[0041] The utility model discloses when assembling, transducer assembly 4 and thermistor 5 are soldered on circuit board 3, and the limiting groove 10 of this combined structure corresponds and inserts into the inside of shell 1, and fills the heat-conducting glue in resistance installation groove 14, and the probe end of thermistor 5 is immersed in the heat-conducting glue, improves the sensing accuracy of thermistor 5, and the wire harness assembly 8 is inserted into the inside of shell 1 from the joint pipe 6, and the bottom end is welded in the connecting end of circuit board 3, further cooperates sealing sleeve 7 and gland 9 and is pressed on joint pipe 6, realizes the sealing of structure between, then uses locking bolt 12 and locks circuit board 3 with shell 1, improves the stability of the structure, and shell 1 is combined and installed with end cover 2, and utilizes polyurethane rubber ring 17 or polyurethane glue layer 22 and carries out the buffer protection between structures, installs anti-bubble rubber sleeve 19 and reflection support 21 at the rear end of shell 1;

[0042] When using, the device is immersed in fluid, due to the good sealing effect of the accommodating cavity, the internal structure of the shell 1 is prevented from being damaged, the fluid flows into the detection area through the outer flow channel hole and the inner flow channel hole, and through the position distribution relationship of the outer flow channel hole and the inner flow channel hole, the external protection is provided in cooperation with the anti-bubble rubber sleeve 19, the urea solution is effectively filtered, and the bubbles in the filling process are discharged, the transducer assembly 4 emits ultrasonic signals, passes through the fluid and is reflected back to the emission / receiving plate by the reflection support 21, detects the fluid, and solves the problem that the bubbles enter the detection area and affect the urea concentration detection.

[0043] The embodiments of the utility model are described in detail in combination with the drawings, but the utility model is not limited to the described embodiments. For those skilled in the art, various changes, modifications, replacements and modifications can be made to these embodiments without departing from the principles and spirits of the utility model, and still fall within the protection scope of the utility model.

Claims

1. An ultrasonic sensor structure, comprising a housing (1) and an end cap (2), characterized in that: The housing (1) and the end cover (2) are provided with a receiving cavity inside, a circuit board (3) is installed in the receiving cavity, and a transducer assembly (4) and a thermistor (5) are soldered to one side of the circuit board (3), a connector tube (6) penetrating the receiving cavity is integrally provided at the top of the housing (1), a sealing kit (7) is detachably installed on the outside of the connector tube (6), a wiring harness assembly (8) is assembled and installed at the connecting end of the circuit board (3), and the sealing kit (7) is interference-fitted on the outside of the end of the wiring harness assembly (8), and the outer diameter of the sealing kit (7) matches the inner diameter of the connector tube (6), a pressure cover (9) is provided on the outside of the wiring harness assembly (8) and located on the top of the sealing kit (7), and the pressure cover (9) and the connector tube (6) are detachably installed.

2. The ultrasonic sensor structure according to claim 1, characterized in that: The access port of the circuit board (3) is arranged opposite to the connector tube (6), and at least two limiting grooves (10) distributed in a ring array are provided on the outside of the circuit board (3), and limiting piles (11) distributed in a one-to-one correspondence with the plurality of limiting grooves (10) are integrally provided on the inner wall of the shell (1), and the circuit board (3) is slidably connected to the limiting piles (11) through the limiting grooves (10), and a threaded hole is provided at the end of the limiting pile (11), and a locking bolt (12) is threadedly connected in the threaded hole to fix the circuit board (3) and the shell (1).

3. The ultrasonic sensor structure according to claim 1, wherein: The circuit board (3) is provided with a groove (13), the inner wall of the housing (1) is provided with a resistor installation groove (14), and the power line of the thermistor (5) is pressed into the groove (13) and extends into the resistor installation groove (14), and the resistor installation groove (14) is filled with thermal conductive glue.

4. The ultrasonic sensor structure according to claim 1, wherein: An annular groove (15) is provided at one end of the shell (1), and an annular platform (16) is integrally provided on the end cover (2), and the annular platform (16) is embedded in and fits into the annular groove (15). A polyurethane rubber ring (17) is provided inside the annular groove (15) for bonding the shell (1) and the end cover (2) into an integrated structure.

5. The ultrasonic sensor structure according to claim 1, characterized in that: An annular platform (16) is integrally provided on the end cover (2), and the annular platform (16) is embedded in and fits the shell (1). The outer wall of the connection between the shell (1) and the end cover (2) is welded, and after the shell (1) and the end cover (2) are combined, a polyurethane adhesive layer (22) is filled between the inner wall of the end cover (2) and the circuit board (3).

6. The ultrasonic sensor structure according to claim 1, characterized in that: Positioning protrusions (18) are fixedly connected to both sides of one end of the shell (1) away from the end cover (2), a slot is reserved between the two positioning protrusions (18), a reflection bracket (21) is clamped between the two slots for reflecting ultrasonic signals, and anti-bubble rubber sleeves (19) are fastened to the outside of the two positioning protrusions (18), and the shell (1) and the anti-bubble rubber sleeve (19) are fixed together by a straight rod bolt (20).

7. The ultrasonic sensor structure according to claim 6, characterized in that: The cross-sectional shape of the reflective bracket (21) is set to be U-shaped, and the bottom plate of the reflective bracket (21) is attached to the inner wall of the anti-bubble rubber sleeve (19), the legs of the reflective bracket (21) match the outer diameter of the card slot, the reflective bracket (21) is nested inside the anti-bubble rubber sleeve (19), and the ends of the legs of the reflective bracket (21) are sleeved on the straight rod bolt (20).

8. The ultrasonic sensor structure according to claim 7, characterized in that: Internal flow channel holes arranged opposite to each other are preset between the two legs of the reflective bracket (21), and a plurality of symmetrically distributed external flow channel holes are passed through the anti-bubble rubber sleeve (19) for guiding the passage of fluid and the discharge of bubbles.

9. The ultrasonic sensor structure according to claim 8, characterized in that: A side of the housing (1) close to the positioning protrusion (18) is provided as a transmitting / receiving plate, a bottom plate of the reflective bracket (21) is provided facing the transmitting / receiving plate, and the reflective bracket (21) and the transmitting / receiving plate form a detection area.

10. The ultrasonic sensor structure according to claim 1, characterized in that: The wiring harness assembly (8) comprises a silicone wiring harness and a heat shrink tubing, and the heat shrink tubing is fitted onto the outside of the silicone wiring harness.

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