High-integration miniaturized magnetoelectric encoder

Abstract

The utility model discloses a high-integration miniaturized magnetoelectric encoder, which relates to the encoder technical field, and comprises a rear cover and a housing buckled with each other, the rear cover is internally provided with a PCBA circuit board, the surface of the PCBA circuit board is provided with a chip in an integrated manner, the interior of the housing is rotatably connected with a shaft body, and the shaft body is internally provided with a rotating shaft. According to the magnetoelectric encoder, through the structural design that a rear cover screw and the like are canceled, detailed explanation of a structural diagram is shown, the problem that more components can be placed in a smaller PCB of a miniature encoder is solved, and it is verified that in addition to a traditional magnet with radial magnetic distribution 2, the magnetic field of the miniature encoder is increased, and the magnetic field of the miniature encoder is increased. The miniature encoder can also adopt a radial magnet with magnetic distribution 1, and higher precision can be achieved by matching with the structural design.

Description

Technical Field

[0001] The utility model relates to the technical field of encoders, in particular to a highly integrated and miniaturized magnetoelectric encoder. Background Technique

[0002] The mainstream encoders on the market now, including optical encoders and magnetic encoders, still have an outer diameter of 38 mm and a shaft diameter of 6 mm (hereinafter referred to as 3806 encoders); due to comprehensive reasons of circuit board components and structures, miniaturization cannot be achieved.

[0003] Most of the existing encoders that are smaller and more miniaturized than 3806 encoders are magnetic encoders, and there is a problem that only one magnetic sensor chip can be arranged on the circuit board, and more components cannot be placed.

[0004] Most of the current magnetoelectric encoders use magnets with a radial magnetic distribution (hereinafter referred to as magnetic distribution 2), because this kind of magnet is easier to match the magnetic sensor chip in the design of magnetoelectric encoders. While the radial magnet (hereinafter referred to as magnetic distribution 1) used in this application is less used in similar products in the past. This encoder verifies that the radial magnet of magnetic distribution 1 can also be applied in miniaturized magnetoelectric encoders, and higher precision can be achieved with a suitable structural design. Content of the Utility Model

[0005] Aiming at the deficiencies of the prior art, the utility model provides a highly integrated and miniaturized magnetoelectric encoder, which solves the problems raised in the above background technique.

[0006] To achieve the above purposes, the utility model is realized through the following technical solutions: a highly integrated and miniaturized magnetoelectric encoder, including a rear cover and a housing that are buckled with each other. A PCBA circuit board is installed inside the rear cover, and chips are integrally arranged on the surface of the PCBA circuit board. A shaft body is rotatably connected inside the housing, and a magnet is embedded at the bottom end of the shaft body.

[0007] Further, the housing and the shaft body are rotatably connected through a first bearing and a second bearing.

[0008] Further, a clamping groove is reserved in the middle of the shaft body, the clamping groove is located above the second bearing, and a snap ring is clamped inside the clamping groove.

[0009] Further, a cavity body is reserved between the PCBA circuit board and the bottom end of the rear cover.

[0010] Further, the chip is a TMR magnetic sensitive chip or GMR or AMR or Hall chip.

[0011] Further, step grooves I and II are respectively reserved on the side walls of the rear cover and the housing. Step groove I can support the PCBA circuit board, and step groove II can limit the axial movement of the PCBA circuit board.

[0012] Further, screw hole positions for installing the entire encoder are reserved at the top of the housing.

[0013] Further, a wire outlet groove is jointly reserved at the bottoms of the rear cover and the housing.

[0014] Further, a shaft sleeve is arranged at the lower part of the shaft body. A magnet is arranged inside the shaft sleeve. The inner diameter of the shaft sleeve is adapted to the outer diameter of the magnet. The shaft body and the magnet are fixed by adhesive.

[0015] The utility model provides a highly integrated and miniaturized magnetoelectric encoder. Compared with the prior art, it has the following beneficial effects:

[0016] Through structural designs such as canceling the rear cover screws (see the explanation in the structure diagram), this magnetoelectric encoder solves the problem that more components can be placed on a smaller PCB board in a miniaturized encoder. It is verified that in addition to the magnets with the traditional radial magnetic distribution 2, the miniaturized encoder can also adopt radial magnets with magnetic distribution 1, and higher precision can be achieved through the cooperation of structural designs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a disassembled schematic diagram of the utility model;

[0018] Figure 2 is an assembly schematic diagram of the utility model;

[0019] Figure 3 is a half-sectional view after the assembly of the utility model;

[0020] Figure 4 is an exploded schematic diagram of the shaft sleeve of the utility model.

[0021] In the figure: 1. Rear cover; 2. Housing; 3. PCBA circuit board; 4. Chip; 5. Shaft body; 6. Magnet; 7. First bearing; 8. Second bearing; 9. Snap ring; 10. Card slot; 11. Cavity body; 12. Wire outlet groove; 13. Shaft sleeve. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0023] Please refer to Figures 1-3 Figures 1-3 , the present utility model provides a technical solution: a highly integrated and miniaturized magnetoelectric encoder, which includes a rear cover 1 and a housing 2 fixed together by a snap structure. A PCBA circuit board 3 is installed inside the rear cover 1. A chip 4 (the chip 4 is any one of a TMR magnetic sensitive chip, GMR, AMR, and Hall chip) is integrally arranged on the surface of the PCBA circuit board 3. A shaft body 5 is rotatably connected inside the housing 2. A magnet 6 is embedded at the bottom end of the shaft body 5. The housing 2 and the shaft body 5 are rotatably connected by a first bearing 7 and a second bearing 8. A card slot 10 is reserved in the middle of the shaft body 5. The card slot 10 is located above the second bearing 8. A snap spring 9 is snap-fitted inside the card slot 10. After the snap spring 9 is stuck inside the card slot 10, the shaft body 5 will not move towards the inside of the housing 2. A cavity 11 is reserved between the PCBA circuit board 3 and the bottom end of the rear cover 1 (other functional chips except the magnetic sensitive chip are integrally arranged at the bottom end of the PCBA circuit board 3. The setting of the cavity 11 is to be able to accommodate more types of the above-mentioned other functional chips. A step groove one and a step groove two are respectively reserved on the side walls of the rear cover 1 and the housing 2. The step groove one can support the PCBA circuit board 3. The step groove two can limit the axial movement of the PCBA circuit board 3. A screw hole position for installing the entire encoder is reserved at the top of the housing 2, which is convenient for installing the entire encoder in the working environment. An outwire groove 12 is jointly reserved at the bottom of the rear cover 1 and the housing 2. The outwire groove 12 can be set to correspond to the shape of different wire materials.

[0024] Please read Figure 4 As shown, a bushing 13 is arranged at the lower part of the shaft body 5. The bushing 13 is made of copper material or other metal materials and non-metal materials. A magnet 6 is arranged inside the bushing 13. The inner diameter of the bushing 13 is adapted to the outer diameter of the magnet 6. The shaft body 5 and the magnet 6 are fixed by an adhesive method. The bushing 13 and the lower part of the shaft body 5 can also be fixed by hard force extrusion or by an adhesive method, or can be fixed by hard force extrusion of the magnet 6 and the bushing 13. Then the bushing 13 is inserted into the lower part of the shaft body 5 and fixed by an adhesive method (the outer diameter of the shaft body 5 is smaller than the inner diameter of the bushing 13), that is, there are 2 ways to fix. To achieve extrusion fixation, the inner diameter and outer diameter dimensions are made into appropriate interference fit dimensions. Copper is non-magnetic. By this method, the distance between the magnet and the bearing can be increased, and the magnetic material of the bearing's interference with the working magnetic field can be reduced, thereby improving the detection accuracy of the encoder. At the same time, the holes for fixing the magnet by the copper sleeve can be made into different diameters to achieve the compatibility of the same encoder shaft with magnets of different diameters.

[0025] It should be noted that:

[0026] 1. The encoder contains a shaft (shaft body 5) or a magnet sleeve that can fix the radial magnets of magnetic distribution 1 and magnetic distribution 2 (the magnetic distribution can be observed with a magnetic display film). The shaft with the radial magnets having the magnetic distribution listed in this application is fixed to the inner rings of two bearings (bearing one 7 and bearing two 8). The bearings connected to the radial magnet shaft with the magnetic distribution listed in this application are respectively fixed in two bearing holes of the encoder housing. The magnetic sensitive chip (especially the TMR chip, also including HALL, AMR, and GMR) is directly below the radial magnet, and the PCB board of the magnetic sensitive chip is connected to the rear cover. The rear cover and the PCB board are fixed to the housing with the rotating shaft having the radial magnet by interference fit or gluing, etc.;

[0027] 2. The encoder contains a shaft with fixed radial magnets. The shaft can be integral or in the form of a magnet sleeve spliced with a shaft;

[0028] 3. The shaft with the radial magnets is fixed to the inner rings of two bearings and is fixed to the encoder housing together with the bearings. The shaft with the radial magnets can rotate 360° with the radial magnets;

[0029] 4. The magnetic sensitive chip is below the shaft with the radial magnets and is directly opposite to the radial magnet.

[0030] 5. The PCBA of the magnetic sensitive chip is fixed between the rear cover and the housing.

[0031] 6. The connection between the rear cover and the housing adopts a connection method without opening holes, including but not limited to gluing and interference fit;

[0032] 7. The height from the inner surface of the rear cover to the PCBA of the magnetic sensitive chip is greater than 0.5 mm to accommodate chips with a wider range of heights;

[0033] 8. There are limit rear covers on the housing and steps for clamping the encoder PCBA;

[0034] 9. The rear cover has steps for cooperating with the housing to clamp the encoder PCBA;

[0035] 10. Enough gaps are designed between the rear cover and the encoder PCBA to be compatible with more types of chips, so as to achieve high integration of the micro encoder.

Claims

1. A highly integrated miniaturized magnetoelectric encoder, comprising a back cover (1) and a housing (2) that are interlocked, characterized in that: A PCBA circuit board (3) is installed inside the rear cover (1), a chip (4) is integrated on the surface of the PCBA circuit board (3), a shaft (5) is rotatably connected inside the housing (2), and a magnet (6) is embedded at the bottom end of the shaft (5); A shaft sleeve (13) is arranged at the lower part of the shaft body (5), a magnet (6) is arranged inside the shaft sleeve (13), the inner diameter of the shaft sleeve (13) is matched with the outer diameter of the magnet (6), and the shaft body (5) and the magnet (6) are fixed by adhesive.

2. The highly integrated miniaturized magnetoelectric encoder according to claim 1, characterized in that: The housing (2) and the shaft (5) are rotatably connected via a first bearing (7) and a second bearing (8).

3. The highly integrated miniaturized magnetoelectric encoder according to claim 1, characterized in that: A retaining groove (10) is reserved in the middle of the shaft body (5), the retaining groove (10) is located above the second bearing (8), and a retaining spring (9) is provided inside the retaining groove (10) for engagement.

4. The highly integrated miniaturized magnetoelectric encoder according to claim 1, characterized in that: A cavity (11) is reserved between the PCBA circuit board (3) and the bottom end of the back cover (1).

5. The highly integrated miniaturized magnetoelectric encoder according to claim 1, characterized in that: The chip (4) is a TMR magnetic sensor chip or a GMR or an AMR or a Hall chip.

6. The highly integrated miniaturized magnetoelectric encoder according to claim 1, characterized in that: The side walls of the rear cover (1) and the housing (2) are respectively provided with a step groove one and a step groove two, wherein the step groove one can support the PCBA circuit board (3), and the step groove two can limit the axial movement of the PCBA circuit board (3).

7. The highly integrated miniaturized magnetoelectric encoder according to claim 1, characterized in that: The top of the housing (2) is reserved with screw holes for installing the entire encoder.

8. The highly integrated miniaturized magnetoelectric encoder according to claim 1, characterized in that: The rear cover (1) and the bottom of the housing (2) are jointly provided with a wire outlet groove (12).

Images