Sensor for detecting position and rotating speed of camshaft

Abstract

The utility model belongs to the technical field of sensors, and particularly relates to a sensor for detecting the position and rotating speed of a camshaft, which comprises a shell and a base, the base is detachably mounted in the shell, and a circuit board and a Hall assembly are arranged on the base; a plurality of positioning ribs are uniformly distributed in the shell in the circumferential direction and are in close fit with the end part of the base; the Hall assembly comprises a permanent magnet, a Hall chip, a plastic package shell and a pin, the permanent magnet and the Hall chip are coated with the plastic package shell through injection molding, a Hall sensing element, a resistor and a capacitor which are electrically connected are arranged in the Hall chip, one end of the pin is electrically connected with the Hall chip, and the other end of the pin penetrates out of the plastic package shell and is electrically connected with the circuit board; the problems that in the prior art, assembling operation is troublesome, errors such as assembling and positioning are prone to occurring, and the signal conversion stability of a sensor is affected are solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of sensors, and in particular relates to a sensor for detecting a camshaft position and a rotation speed. Background Art

[0002] The Hall sensor is a sensor based on the Hall effect. The rotation of the engine cam causes the magnetic field strength at the sensor sensing point to change. When the cam tooth top is in front of the sensor, the magnetic field strength increases; when the cam tooth groove is in front of the sensor, the magnetic field strength decreases, and the magnetic field change is recognized by the Hall element. Through this principle, the mechanical rotation of the camshaft cam can be converted into a corresponding output level voltage signal; the sensor provides the characteristic of signal power-on. When the cam does not rotate after power-on, the sensor can still output a valid signal. Therefore, it can achieve rapid cylinder judgment, thereby effectively reducing emissions at startup.

[0003] The utility model patent with announcement number CN 207850275 U discloses a sensor with stable induction, including a shell, a sensor and a base. The sensor and the base are detachably connected, the base is located inside the shell, at least a part of the sensor is arranged in the shell, a circuit board assembly is installed on the base, a Hall chip is arranged on the circuit board assembly, an opening groove is opened at the opening of the base, a permanent magnet is installed in the opening groove, and a magnetic conductive sheet is arranged between the permanent magnet and the bottom of the shell; the Hall chip, permanent magnet and magnetic conductive sheet of the patent adopt a split structure, which is troublesome to operate during assembly, and is prone to errors such as assembly positioning, resulting in excessive deviation of the phase accuracy of the sensor, thereby affecting the signal conversion stability of the sensor. Utility Model Content

[0004] The utility model aims to provide a sensor for detecting the position and speed of a camshaft, so as to solve the problems of the prior art that the assembly operation is cumbersome, errors such as assembly positioning are prone to occur, and the signal conversion stability of the sensor is affected.

[0005] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0006] A sensor for detecting the position and rotation speed of a camshaft comprises a shell and a base, wherein the base is detachably mounted in the shell, and a circuit board and a Hall assembly are arranged on the base; a plurality of positioning ribs are evenly distributed in the circumferential direction of the shell, and the positioning ribs are tightly matched with the ends of the base; the Hall assembly comprises a permanent magnet, a Hall chip, a plastic package shell and pins, wherein the plastic package shell is injection-molded around the permanent magnet and the Hall chip, wherein an electrically connected Hall sensing element, a resistor and a capacitor are arranged in the Hall chip, wherein one end of the pin is electrically connected to the Hall chip, and the other end of the pin passes through the outside of the plastic package shell and is electrically connected to the circuit board.

[0007] Furthermore, the shell is provided with a mounting hole, and two limiting holes are symmetrically provided on the side wall of the mounting hole; a connecting head is provided at one end of the base, and two limiting spring plates are symmetrically provided at the bottom of the connecting head, and the end of the limiting spring plate is provided with a protrusion that can be inserted into the limiting hole.

[0008] Furthermore, the shell is provided with a guide notch, and the base is provided with a guide plate, and the guide plate can be inserted into the guide notch.

[0009] Furthermore, the shell is provided with a first annular groove, an outer sealing ring is provided in the first annular groove, the base is provided with a second annular groove, and an inner sealing ring is provided in the second annular groove.

[0010] Furthermore, a first vertical groove is provided in the mounting hole of the shell, and a second vertical groove communicating with the second annular groove is provided on the base, and the positions of the first vertical groove and the second vertical groove are correspondingly arranged.

[0011] Furthermore, a connecting hole and a positioning pin are provided on one side of the base away from the connector, and the Hall component is installed in the connecting hole; a positioning hole and a socket are provided on the circuit board, the positioning pin of the base is inserted into the positioning hole, and the pin of the Hall component is inserted into the socket of the circuit board.

[0012] Furthermore, a mounting plate is provided in the middle of the shell, a through hole for connecting screws is provided on the mounting plate, and a metal bushing is provided in the through hole.

[0013] Furthermore, a process hole is provided on the end surface of the mounting plate.

[0014] Compared with the prior art, the utility model has the following beneficial technical effects:

[0015] 1. The utility model integrates the permanent magnet, the Hall chip and the pins into an integrated structure through a plastic package, which can reduce the assembly process of the sensor. The sensor assembly operation is simple and quick, and the Hall component is integrated by injection molding and encapsulation, which avoids positioning errors during the assembly process of the Hall component, making the signal conversion of the sensor stable and reliable.

[0016] 2. The utility model arranges positioning ribs in the mounting hole of the shell so that after the lower end of the base is inserted into the mounting hole, the positioning ribs can automatically clamp the lower end of the base, and the positioning ribs and the lower end of the base fit tightly with no gap, so that the base and the shell are located on the same axis, thereby ensuring the assembly stability of the base and the shell.

[0017] 3. The utility model can ensure the sealing between the sensor and the target mounting hole by arranging an outer sealing ring on the outer shell; can ensure the sealing between the base and the outer shell by arranging an inner sealing ring on the base; and can reduce the internal and external pressure difference of the mounting hole during assembly by arranging the first vertical groove and the second vertical groove, so that the base can be smoothly inserted into the mounting hole of the outer shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the utility model;

[0019] Figure 2 It is the structural explosion diagram of the utility model;

[0020] Figure 3 It is a cross-sectional view of the utility model;

[0021] Figure 4 This is an exploded view of the structure of the Hall component of the utility model;

[0022] Figure 5 It is a cross-sectional view of the Hall assembly of the present utility model;

[0023] Figure 6 It is a top view of the housing of the utility model;

[0024] Figure 7 for Figure 6 Cross-sectional view along the AA direction. DETAILED DESCRIPTION

[0025] The following is further described in detail through specific implementation methods:

[0026] The reference numerals in the drawings of the specification include:

[0027] Shell 1, mounting hole 11, positioning rib 12, limiting hole 13, guide notch 14, first annular groove 15, outer sealing ring 151, first vertical groove 16, mounting plate 17, process hole 171, metal bushing 18;

[0028] Base 2, connector 21, connecting hole 22, limiting spring piece 23, protrusion 231, guide plate 24, second annular groove 25, inner sealing ring 251, second vertical groove 26, positioning pin 27;

[0029] Circuit board 3, positioning hole 31, plug hole 32;

[0030] Hall assembly 4 , permanent magnet 41 , Hall chip 42 , Hall sensing element 421 , resistor 422 , capacitor 423 , plastic package 43 , pin 44 .

[0031] Example

[0032] like Figure 1-3, 6-7, a sensor for detecting the position and speed of a camshaft, comprising a housing 1 and a base 2, the housing 1 being formed with a mounting hole 11, the bottom of the mounting hole 11 being formed with a plurality of positioning ribs 12, in this embodiment, four positioning ribs 12 are provided, and the four positioning ribs 12 are evenly distributed in the mounting hole 11 in the circumferential direction; the base 2 is detachably mounted in the mounting hole 11 of the housing 1, and a connector 21 and a connecting hole 22 are respectively formed at both ends of the base 2, the connector 21 is located outside the mounting hole 11, and a Hall assembly 4 is installed in the connecting hole 22; as shown in FIG. Figure 4-5 As shown, the Hall component 4 includes a permanent magnet 41, a Hall chip 42, a plastic package 43 and three pins 44. The permanent magnet 41 is formed with a large-diameter hole and a small-diameter hole that are interconnected. The Hall chip 42 is installed in the large-diameter hole. The plastic package 43 is injection-molded around the permanent magnet 41 and the Hall chip 42. The Hall chip 42 is provided with an electrically connected Hall sensing element 421, a resistor 422 and a capacitor 423. One end of the three pins 44 is electrically connected to the Hall chip 42, and the other end of the three pins 44 passes through the plastic package 43 and is electrically connected to the circuit board 3.

[0033] The permanent magnet 41, the Hall chip 42 and the pin 44 are integrated into an integrated structure through the plastic package 43, which can reduce the assembly process of the sensor. The sensor assembly operation is simple and quick, and the Hall component 4 is integrated by injection molding to avoid positioning errors during the assembly of the Hall component 4, so that the signal conversion of the sensor is stable and reliable.

[0034] like Figure 2 and 3 As shown, two limiting holes 13 and a guide notch 14 are symmetrically provided on the side wall of the mounting hole 11, and two limiting spring pieces 23 and a guide plate 24 are symmetrically formed at the bottom of the connector 21, and protrusions 231 are formed at the ends of the two limiting spring pieces 23; during installation, the base 2 is inserted into the mounting hole 11, so that the guide plate 24 is inserted into the guide notch 14, and the protrusions 231 on the limiting spring pieces 23 are inserted into the corresponding limiting holes 13.

[0035] By cooperating with the guide plate 24 and the guide notch 14, and the limiting spring piece 23 and the limiting hole 13, a guiding and limiting function can be achieved, and relative rotation between the shell 1 and the base 2 can be prevented, making the assembly process more convenient and efficient. Moreover, after the shell 1 and the base 2 are assembled, the positioning ribs 12 in the mounting hole 11 are tightly matched with the end of the base 2, and the four positioning ribs 12 automatically clamp the end of the base 2, so that the base 2 and the shell 1 are located on the same axis, thereby ensuring the assembly stability of the base 2 and the shell 1.

[0036] like Figure 2-3As shown in 6-7, a first annular groove 15 is formed on the outer shell 1, and an outer sealing ring 151 is clamped in the first annular groove 15; a second annular groove 25 is formed on the base 2, and an inner sealing ring 251 is clamped in the second annular groove 25; four first vertical grooves 16 are formed in the mounting hole 11 of the outer shell 1, and four second vertical grooves 26 are formed on the base 2, the second vertical grooves 26 are connected with the second annular grooves 25, and the number and positions of the first vertical grooves 16 and the second vertical grooves 26 are correspondingly arranged.

[0037] By setting an outer sealing ring 151 on the outer shell 1, the sealing between the sensor and the target mounting hole 11 can be ensured; by setting an inner sealing ring 251 on the base 2, the sealing between the base 2 and the outer shell 1 can be ensured, and by setting the first vertical groove 16 and the second vertical groove 26, the internal and external pressure difference of the mounting hole 11 can be reduced during assembly, so that the base 2 can be smoothly inserted into the mounting hole 11 of the outer shell 1.

[0038] like Figure 2 and 3 As shown, a mounting platform is formed on one side of the base 2 near the connecting hole 22, three positioning pins 27 are fixed on the mounting platform, and three positioning holes 31 and three plug holes 32 are opened on the circuit board 3; during installation, the Hall component 4 is first installed in the connecting hole 22 of the base 2, and then the circuit board 3 is placed above the mounting platform of the base 2, so that the three positioning pins 27 of the base 2 are respectively plugged into the three positioning holes 31 of the circuit board 3, and the three pins 44 of the Hall component 4 are respectively plugged into the three plug holes 32 of the circuit board 3 to achieve electrical connection.

[0039] like Figure 2 As shown, a mounting plate 17 is formed in the middle of the housing 1, and a through hole for connecting screws is formed on the mounting plate 17. A metal bushing 18 is fixed in the through hole. The metal bushing 18 can withstand the pre-tightening force of tightening the screws when installing the sensor to avoid damaging the mounting plate 17; two process holes 171 are formed on the lower end surface of the mounting plate 17. The mounting plate 17 has a large injection shrinkage during injection molding. By setting the process holes 171, the influence of injection shrinkage on the flatness of the end surface of the mounting plate 17 can be reduced, so that the mounting plate 17 can fit more closely with the target installation position during installation.

[0040] The above is only an embodiment of the utility model, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the utility model, several deformations and improvements can be made, which should also be regarded as the protection scope of the utility model, and these will not affect the effect of the implementation of the utility model and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A sensor for detecting a camshaft position and rotation speed, comprising a housing (1) and a base (2), wherein the base (2) is detachably mounted in the housing (1), and a circuit board (3) and a Hall component (4) are arranged on the base (2), characterized in that: A plurality of positioning ribs (12) are evenly distributed in the circumferential direction of the housing (1), and the positioning ribs (12) are tightly matched with the ends of the base (2); the Hall assembly (4) comprises a permanent magnet (41), a Hall chip (42), a plastic package (43) and a pin (44); the plastic package (43) is injection-molded around the permanent magnet (41) and the Hall chip (42); an electrically connected Hall sensing element (421), a resistor (422) and a capacitor (423) are arranged in the Hall chip (42); one end of the pin (44) is electrically connected to the Hall chip (42), and the other end of the pin (44) passes through the outside of the plastic package (43) and is electrically connected to the circuit board (3).

2. A sensor for detecting camshaft position and speed according to claim 1, characterized in that: The housing (1) is provided with a mounting hole (11), and two limiting holes (13) are symmetrically provided on the side wall of the mounting hole (11); a connecting head (21) is provided at one end of the base (2), and two limiting spring sheets (23) are symmetrically provided at the bottom of the connecting head (21), and a protrusion (231) capable of being inserted into the limiting hole (13) is provided at the end of the limiting spring sheet (23).

3. A sensor for detecting camshaft position and speed according to claim 2, characterized in that: The housing (1) is provided with a guide notch (14), and the base (2) is provided with a guide plate (24), and the guide plate (24) can be inserted into the guide notch (14).

4. A sensor for detecting camshaft position and rotation speed according to any one of claims 1 to 3, characterized in that: The housing (1) is provided with a first annular groove (15), an outer sealing ring (151) is provided in the first annular groove (15), and the base (2) is provided with a second annular groove (25), an inner sealing ring (251) is provided in the second annular groove (25).

5. A sensor for detecting camshaft position and rotation speed according to claim 4, characterized in that: A first vertical groove (16) is provided in the mounting hole (11) of the housing (1), and a second vertical groove (26) communicating with the second annular groove (25) is provided on the base (2), and the positions of the first vertical groove (16) and the second vertical groove (26) are correspondingly arranged.

6. A sensor for detecting camshaft position and rotation speed according to any one of claims 2 or 3, characterized in that: A connection hole (22) and a positioning pin (27) are provided on a side of the base (2) away from the connector (21), and the Hall component (4) is installed in the connection hole (22); a positioning hole (31) and a plug hole (32) are provided on the circuit board (3), the positioning pin (27) of the base (2) is plugged into the positioning hole (31), and the pin (44) of the Hall component (4) is plugged into the plug hole (32) of the circuit board (3).

7. A sensor for detecting camshaft position and rotation speed according to any one of claims 1 to 3, characterized in that: A mounting plate (17) is provided in the middle of the housing (1), and a through hole for connecting a screw is provided on the mounting plate (17), and a metal bushing (18) is provided in the through hole.

8. A sensor for detecting camshaft position and rotation speed according to claim 7, characterized in that: A process hole (171) is provided on the end surface of the mounting plate (17).

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