Linear motor Hall switch sensing structure and head-up display motor comprising same

Abstract

The utility model discloses a Hall switch induction structure of a linear motor and a head-up display motor comprising the Hall switch induction structure, which comprises a circuit board arranged on the radial outer side of a motor assembly and induction magnetic steel arranged on a sliding block assembly, the side, close to the motor assembly, of the sliding block assembly is provided with an installation groove extending outwards, and the induction magnetic steel is located in the installation groove. When the induction magnetic steel moves to the induction range of the Hall sensor, the output screw of the motor assembly stops moving. According to the utility model, the Hall sensor is installed on the external circuit board, the installation groove for accommodating the induction magnetic steel is additionally arranged on the slide block assembly, and the motion state of the motor is controlled in a non-contact manner, so that the slide block assembly stops when moving to the lowest end, and compared with a traditional contact switch, a mistaken touch phenomenon does not occur; and the precision reduction caused by long-time use is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of automotive parts, in particular to a linear motor Hall switch induction structure and a head-up display motor including the same. Background Art

[0002] In the design of traditional linear motors, the linear motion stroke limit of the slider is usually controlled by a contact switch, such as a micro switch. A micro switch is a mechanical electronic switch that requires an external force to press down the trigger head of the micro switch to control the switch. It has high requirements for the applied force, and there will be problems such as the switch being in a quasi-connected or non-connected state and secondary triggering. In addition, the contact switch has a wear problem, resulting in a reduction in control accuracy and further a reduction in the service life of the motor.

[0003] In traditional linear motors, non-contact Hall elements are also used to control the movement of the motor. However, the Hall elements are only used for measuring the rotational speed of the motor or precisely controlling the stroke of the motor. The Hall elements are installed at the end of the motor, and multiple magnetic steel pieces cooperating with the Hall elements are directly attached to one end of the motor shaft. This structure can only control the start and stop of the motor when one of the magnetic steel pieces rotates relative to the Hall element. The more the number of magnetic steel pieces, the higher the control accuracy. Usually, it is impossible to accurately control the motor to stop at its stroke limit position.

[0004] Therefore, how to design a linear motor switch structure with high control accuracy and long service life is a technical problem that needs to be solved at present. Summary of the Utility Model

[0005] In order to solve the technical problems that the linear motor in the prior art relies on a contact switch to control the start and stop of the motor at the limit position, resulting in low control accuracy and low service life of the motor, the utility model provides a linear motor Hall switch induction structure and a head-up display motor including the same to solve the above problems.

[0006] The utility model provides a linear motor Hall switch induction structure, which includes a circuit board installed on the radial outer side of the motor assembly and an induction magnetic steel installed on the slider assembly. A Hall sensor is fixed on the circuit board. One side of the slider assembly close to the motor assembly has a mounting groove extending outward. The induction magnetic steel is located in the mounting groove. When the induction magnetic steel moves to the induction range of the Hall sensor, the output screw of the motor assembly stops moving.

[0007] Further, the Hall sensor is a unipolar sensor.

[0008] Further, the mounting groove extends radially out of the slider assembly and is arranged parallel to the circuit board. The minimum distance between the mounting groove and the Hall sensor is greater than the minimum distance between the outer side surface of the slider assembly and the Hall sensor.

[0009] Further, the installation groove includes a first retaining arm and a second retaining arm that are oppositely arranged and parallel to the circuit board, and an upper baffle and a lower baffle that are oppositely arranged and perpendicular to the circuit board. The first retaining arm is arranged on the side close to the Hall sensor, and the length of the first retaining arm is less than that of the second retaining arm. The end of the second retaining arm has a hook for abutting against the induction magnet.

[0010] Further, the induction magnet is a bar magnet with two poles, and the Hall sensor faces the S extreme surface of the induction magnet.

[0011] Further, the two poles of the induction magnet are perpendicularly magnetized on two parallel end faces of the induction magnet.

[0012] Further, after the induction magnet is installed in the installation groove, the surface of the induction magnet facing the motor assembly is in the same plane as the lower surface of the slider assembly.

[0013] Further, the circuit board is fixed to the wire outlet box of the motor assembly by screws.

[0014] The present utility model further provides a head-up display motor, which includes a bracket, a motor assembly installed on the bracket, a slider assembly threadedly engaged with the output screw of the motor assembly, and the linear motor Hall switch induction structure described above. The bracket is provided with guide posts for guiding the up and down movement of the slider assembly.

[0015] Further, limiting posts are provided on both the upper and lower end faces of the slider assembly, and the limiting post of the slider assembly facing the motor assembly protrudes from the lower surface of the installation groove.

[0016] The beneficial effects of the present utility model are as follows:

[0017] (1) In the present utility model, a Hall sensor is installed on an external circuit board, and at the same time, an installation groove for accommodating an induction magnet is added to the slider assembly. The motion state of the motor is controlled in a non-contact manner, so that the slider assembly stops when it moves to the lowermost end. Compared with the traditional contact switch, there will be no mis-touch phenomenon, nor will the accuracy be reduced due to long-term use.

[0018] (2) In the installation groove of the present utility model, a groove for accommodating the induction magnet is surrounded by four plates. The length of the first retaining arm on the side facing the Hall sensor is shorter, so that the induction magnet can be exposed. A hook is provided on the second retaining arm to press the induction magnet, preventing the induction magnet from falling off.

[0019] (3) The present utility model can be applied to the field of servo motor drive and control integration systems. Description of the Drawings

[0020] The present utility model will be further described below in conjunction with the drawings and embodiments.

[0021] Figure 1It is the front view of the specific embodiment of the head-up display motor described in the present utility model;

[0022] Figure 2 It is the exploded view of the head-up display motor described in the present utility model;

[0023] Figure 3 It is the schematic diagram when the Hall switch induction structure of the linear motor described in the present utility model is in the non-inductive position

[0024] Figure 4 It is the schematic diagram when the Hall switch induction structure of the linear motor described in the present utility model is in the inductive position;

[0025] Figure 5 It is the schematic diagram of the front-back direction position of the installation groove on the slider assembly described in the present utility model;

[0026] Figure 6 It is the schematic diagram of the left-right direction position of the installation groove on the slider assembly described in the present utility model;

[0027] Figure 7 It is the three-dimensional view of the slider assembly described in the present utility model;

[0028] Figure 8 It is the schematic diagram of the assembly structure of the circuit board.

[0029] In the figure, 1. Motor assembly, 101. Circuit board, 102. Output screw, 103. Wire outlet box, 2. Slider assembly, 201. Limit post, 3. Hall sensor, 4. Installation groove, 401. First stop arm, 402. Second stop arm, 403. Upper baffle, 404. Lower baffle, 405. Hook, 5. Inductive magnet, 6. Bracket, 601. Guide post, 7. Pressure plate, 8. Spring. Specific embodiment

[0030] The embodiments of the present utility model will be described in detail below. The examples of the embodiments are shown in the drawings, in which the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation of the present utility model.

[0031] Such as Figures 1 - 5As shown in the figure, a Hall switch induction structure for a linear motor includes a circuit board 101 installed on the radial outer side of the motor assembly 1 and an induction magnet 5 installed on the slider assembly 2. A Hall sensor 3 is fixed on the circuit board 101. One side of the slider assembly 2 close to the motor assembly 1 has a mounting groove 4 extending outward. The induction magnet 5 is located in the mounting groove 4. When the induction magnet 5 moves to the induction range of the Hall sensor 3, the output screw 102 of the motor assembly 1 stops moving. The induction range is an induction tolerance set according to problems such as the magnetic force strength of the induction magnet 5 itself. It is a normal phenomenon that the Hall element senses the signal of the induction magnet 5 within the induction range.

[0032] The circuit board 101 of a conventional motor is located at the end of the stator coil inside the motor. In the present invention, the circuit board is arranged outside the motor. The Hall sensor 3 is welded on the circuit board 101 through a professional chip mounter, enabling the Hall sensor 3 to cooperate with the externally moving induction magnet 5. The induction surface of the induction magnet 5 and the Hall sensor 3 is parallel to the moving direction of the slider assembly 2. When the slider assembly 2 moves downward to the induction range of the Hall sensor 3, the induction magnet 5 changes the magnetic field around the Hall sensor 3, and the Hall sensor 3 generates a potential difference. After being amplified and filtered by a capacitance-resistance adjustment circuit, the output electrical signal is recognized by the host computer, and after recognition, the host computer issues an instruction to adjust the motor.

[0033] As shown in Figure 3, at any position on the motor assembly 1 where the Hall sensor 3 on the slider assembly 2 cannot sense, at this time, the Hall sensor 3 does not sense the magnetic field emitted by the induction magnet 5. At this time, the Hall sensor 3 will also output a Hall voltage signal, and this Hall voltage signal is a high level. When the external drive electronic control receives the high-level signal, it will continuously send pulse signals to drive the slider assembly 2 to move downward continuously.

[0034] As shown in Figure 4, when the slider assembly 2 moves downward continuously, since the induction magnet 5 is embedded on the slider assembly 2, the distance from the Hall sensor 3 on the circuit board 101 is getting closer and closer. The Hall sensor 3 begins to sense the magnetic field emitted by the induction magnet 5. When the magnetic field strength reaches a certain level, it activates the sensor on the circuit board 101, and the Hall sensor 3 outputs a Hall voltage signal. At this time, the Hall voltage signal is a low level. When the low-level signal is output to the external drive electronic control through the circuit board 101, after the electronic control receives the signal, it issues a signal instruction to the motor assembly 1, instructing the motor assembly 1 to stop or reverse.

[0035] The Hall induction structure of the present utility model adopts the magnetic induction method. Without the need for external force contact, there is no wear problem, which improves the entire life cycle of the motor. In the operation of a traditional micro switch, it is necessary to rely on external force to press the trigger head of the micro switch, and there will be problems such as the switch being in a state of being seemingly connected or not connected and secondary triggering, while the Hall induction structure will not have such a phenomenon. The reliability is greatly improved, and the operation accuracy is high. Since the Hall sensor 3 is a high-precision induction component, compared with the traditional micro trigger switch, the accuracy will not decrease with the increase of the use time.

[0036] In the present utility model, the induction principle of the Hall sensor 3 is the same as that of the Hall sensor 3 installed at the end of the motor in the prior art, that is, after being amplified and filtered by a capacitance-resistance adjustment circuit, an electrical signal is output. The difference is that after the Hall sensor 3 in the present utility model outputs an electrical signal, it is not used for further counting or calculating the number of rotation cycles, but to send a stop or reverse instruction to the motor. This control program is the prior art. The present utility model proposes a new Hall induction structure, which brings new functions through changes in the installation structure and installation position. Therefore, the control circuit of the Hall sensor 3 is not described in the present utility model.

[0037] Since the Hall sensor 3 in the present utility model only needs to cooperate with one magnetic pole of the induction magnet 5 to achieve the above functions, the Hall sensor 3 can be a unipolar sensor.

[0038] Only one Hall sensor 3 needs to be set on the circuit board 101 to sense the axial distance when the slider assembly 2 operates. The single Hall control is simple and there will be no situation of misjudgment in induction.

[0039] Regarding the design of the induction magnet 5, the induction magnet 5 is preferably a bar magnet with two poles. The bar magnet structure is simple, easy to process, and has high magnetic pole stability. The Hall sensor 3 is opposite to the S extreme surface of the induction magnet 5. In terms of the magnetization method, the induction magnet 5 can be magnetized from any direction to the end surface, but this will cause uneven magnetism on the surface of the magnet or magnetic leakage. Therefore, the present utility model preferably magnetizes the two poles of the induction magnet 5 vertically on the two parallel end surfaces of the induction magnet 5. The effect shown is that the magnetic properties of the two sides of the induction magnet 5 are the strongest, and the polarities do not interfere with each other. One side is the N pole and the other side is the S pole. In this way, the Hall sensor 3 will only sense the required pole during induction and there will be no polarity interference.

[0040] Regarding the position design of the installation groove 4: Since the end surface of the induction magnet 5 needs to be directly opposite to the Hall sensor 3, the installation groove 4 is arranged parallel to the circuit board 101. In addition, to avoid the induction magnet 5 occupying the axial space, the installation groove 4 is selected to extend radially out of the slider assembly 2. Axially, the induction magnet 5 will not protrude from the slider assembly 2, as Figure 7As shown, the slider assembly 2 is a cuboid structure. Let the movement direction of the slider assembly 2 be the up-and-down direction. The left-and-right direction of the slider assembly 2 is parallel to the extending direction of the circuit board 101. The installation groove 4 extends in the front-and-back direction of the slider assembly 2 (as Figure 5 shown).

[0041] To avoid the induction magnet 5 rubbing against and colliding with the Hall sensor 3 on the circuit board 101 during movement, the position of the installation groove 4 in the left-and-right direction of the slider assembly 2 needs to be limited, that is, it is preferably that the minimum distance between the installation groove 4 and the Hall sensor 3 is greater than the minimum distance between the outer side surface of the slider assembly 2 and the Hall sensor 3. The minimum distance described here refers to the minimum value of the distance in the left-and-right direction of the slider assembly 2. As Figure 6 shown, there is a certain distance dimension between the installation groove 4 on the side surface of the slider assembly 2 and the side surface of the slider assembly 2 (the dimension distance is calculated according to the magnetic field strength when the Hall trigger signal is generated). On the one hand, this can ensure that when the motor assembly 1 is running, the installation groove 4 will not hit the Hall sensor 3. Second, this can ensure that when the Hall sensor 3 triggers a signal, the position where the motor assembly 1 stops meets the usage requirements.

[0042] The arrangement position of the installation groove 4 in the up-and-down direction of the slider assembly 2 determines the timing of the motor stop or reverse. Since the induction range of the Hall sensor 3 is small, to avoid the slider assembly 2 colliding with the motor assembly 1, it is preferably that after the induction magnet 5 is installed in the installation groove 4, the surface of the induction magnet 5 facing the motor assembly 1 is in the same plane as the lower surface of the slider assembly 2. That is, the induction magnet 5 is located at the lowest position of the slider assembly 2.

[0043] The installation groove 4 is used to install the induction magnet 5, which can be fixed by welding or by interference fit. The present invention adopts the following structure of the installation groove 4:

[0044] As Figure 5 and Figure 7As shown in the figure, the installation groove 4 includes a first retaining arm 401 and a second retaining arm 402 that are oppositely arranged and parallel to the circuit board 101, and an upper baffle 403 and a lower baffle 404 that are oppositely arranged and perpendicular to the circuit board 101. The first retaining arm 401 is arranged on the side close to the Hall sensor 3, and the length of the first retaining arm 401 is less than that of the second retaining arm 402. The end of the second retaining arm 402 has a hook 405 that abuts against the induction magnet 5. As shown in the figure, the space enclosed by the four plate-like structures of the first retaining arm 401, the second retaining arm 402, the upper baffle 403, and the lower baffle 404 can accommodate the induction magnet 5. These four plate-like structures can be non-connected to each other, facilitating the installation of the induction magnet 5. The first retaining arm 401 is located between the induction magnet 5 and the Hall sensor 3, so its length is shorter, and the induction surface of the induction magnet 5 can be exposed without affecting the induction effect. The hook 405 extends from the end of the second retaining arm 402 into the interior of the installation groove 4. After the induction magnet 5 is installed, the hook 405 can abut against its end to prevent the induction magnet 5 from falling out of the outlet of the space enclosed by the four plates. The distance between the two parallel plates is determined according to the size of the induction magnet 5, and preferably has an interference fit with the induction magnet 5, so as to ensure that the induction magnet 5 will not loosen under external force impact after installation.

[0045] The installation position of the circuit board 101 is as Figure 8 shown, on the wire outlet box 103 of the motor assembly 1. The circuit board 101 and the wire outlet box 103 are preferably fixed by screws, which can well ensure that the circuit board 101 will not be displaced during the use of the motor.

[0046] The present utility model also proposes a head-up display motor, as Figure 1 and Figure 2 shown, including a bracket 6, a motor assembly 1 installed on the bracket 6, a slider assembly 2 threadedly engaged with the output screw 102 of the motor assembly 1, and the linear motor Hall switch induction structure described above. The bracket 6 has a guide post 601 for guiding the up and down movement of the slider assembly 2, which can not only reduce the force on the output screw 102 but also improve the straightness of the movement of the slider assembly 2.

[0047] The upper and lower end faces of the slider assembly 2 are preferably provided with limit posts 201. The limit posts 201 on the slider assembly 2 facing the motor assembly 1 protrude from the lower surface of the installation groove 4. The setting of the limit posts 201 can prevent the functional components on the slider assembly 2 from colliding with external structures. For the limit posts 201 above the slider assembly 2, they are mainly used to Figure 2The pressing plate 7 collides, and under the action of the spring 8 above the pressing plate 7, the slider assembly 2 is driven to move in the reverse direction, which can avoid the collision and damage of the threaded connection structure at the center with the output screw 102. For the limit post 201 below the slider assembly 2, it needs to protrude from the lower surface of the installation groove 4. On the one hand, if there is a problem with the induction signal of the Hall sensor 3, resulting in the slider assembly 2 not stopping in time, then the limit post 201 will play a limiting role to prevent the slider assembly 2 from continuing to move downward. On the other hand, the limit post 201 contacts the bracket 6 first, avoiding the installation groove 4 from abutting against the bracket 6, thereby preventing damage to the structure of the installation groove 4 and the induction magnet 5 inside.

[0048] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", "axial", "radial", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0049] In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0050] In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments.

[0051] Based on the above inspiration from the ideal embodiment of the present invention, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A Hall switch induction structure for a linear motor, characterized in that: It includes a circuit board (101) installed on the radial outer side of the motor assembly (1) and an induction magnet (5) installed on the slider assembly (2). A Hall sensor (3) is fixed on the circuit board (101). On one side of the slider assembly (2) close to the motor assembly (1), there is an installation groove (4) extending outward. The induction magnet (5) is located in the installation groove (4). When the induction magnet (5) moves to the induction range of the Hall sensor (3), the output screw (102) of the motor assembly (1) stops moving.

2. The Hall switch induction structure of the linear motor according to claim 1, wherein: The Hall sensor (3) is a unipolar sensor.

3. The Hall switch induction structure of the linear motor according to claim 1, wherein: The installation groove (4) extends radially out of the slider assembly (2) and is arranged parallel to the circuit board (101). The minimum distance between the installation groove (4) and the Hall sensor (3) is greater than the minimum distance between the outer side surface of the slider assembly (2) and the Hall sensor (3).

4. The Hall switch induction structure of the linear motor according to claim 1, characterized in that: The installation groove (4) includes a first stop arm (401) and a second stop arm (402) arranged oppositely and parallel to the circuit board (101), and an upper baffle (403) and a lower baffle (404) arranged oppositely and perpendicular to the circuit board (101). The first stop arm (401) is arranged on the side close to the Hall sensor (3), and the length of the first stop arm (401) is less than the length of the second stop arm (402). The end of the second stop arm (402) has a hook (405) that abuts against the induction magnet (5).

5. The Hall switch induction structure of the linear motor according to claim 1, characterized in that: The induction magnet (5) is a bar magnet with two poles, and the Hall sensor (3) faces the S-pole end face of the induction magnet (5).

6. The Hall switch induction structure of the linear motor according to claim 5, characterized in that: The two poles of the induction magnet (5) are magnetized perpendicularly on two parallel end faces of the induction magnet (5).

7. The Hall switch induction structure of the linear motor according to claim 1, characterized in that: After the induction magnet (5) is installed in the installation groove (4), the surface of the induction magnet (5) facing the motor assembly (1) is in the same plane as the lower surface of the slider assembly (2).

8. The Hall switch induction structure of the linear motor according to any one of claims 1-7, characterized in that: The circuit board (101) is fixed on the wire outlet box (103) of the motor assembly (1) by screws.

9. A head-up display motor, characterized in that: It includes a bracket (6), a motor assembly (1) installed on the bracket (6), a slider assembly (2) threadedly engaged with the output screw (102) of the motor assembly (1), and the linear motor Hall switch induction structure according to any one of claims 1-8. The bracket (6) has a guide post (601) for guiding the up and down movement of the slider assembly (2).

10. The head-up display motor according to claim 9, wherein: Limit posts (201) are provided on both the upper and lower end faces of the slider assembly (2). The limit post (201) on the slider assembly (2) facing the motor assembly (1) protrudes from the lower surface of the installation groove (4).

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