A kind of external hall displacement transducer
Technical field
The invention belongs to displacement transducer technology fields, more particularly, to a kind of external hall displacement transducer.
Background technique
When there is the magnetic field perpendicular to electric current, then Hall effect occurs.In this case, magnetic field is perpendicular to magnetic field
The potential difference for being referred to as Hall voltage is generated on direction and the direction extended perpendicular to current direction, the measurement of Hall voltage makes
It must can determine the size of each component in magnetic field.When magnet and Hall chip relative motion, chip perceives position magnetic field
The variation in direction switchs to required electric signal by Hall chip and PCB assembly circuit, corresponds with relative displacement, thus
Know displacement.
Currently, in automobile brake system, in the electric control brake system that especially industry is competitively developed at this stage, brake system
System controller perceives brake pedal displacement by sensor, and the brake for specifying driver is intended to, and further combined with vehicle
Other operating parameters, comprehensive descision, control brake.Since touch sensor contact is prone to wear, and working environment adaptability
Poor, abrasion, vibration, dust and oxidation etc. may cause poor contact, influence the function of sensor.Hall displacement transducer
As a kind of contactless sensor, not only working environment adaptability is strong, while having the characteristics that high precision and fast response, often
For detecting brake pedal displacement in brake system.
Since existing hall displacement transducer is to realize position detection by the magnetic line of force angle of detection variation mostly
, thus there are problems that detection accuracy and measurement stroke mutually restrict-as shown in Figure 1, if it is desired to stroke extension measure model
It encloses, then must lengthen magnet or pulls open spacing, then for the magnetic line of force angle change of segment section just than more gentle, angle change is gentle,
The corresponding magnetic line of force angle change of Hall chip detection is little, and detection accuracy is then lower;If it is desired to allowing magnetic line of force variation fastly it is necessary to contracting
Small magnet spacing, detection accuracy can then improve, but can be reduced therewith with displacement detecting stroke;Simultaneously because stopping in brake system
Vehicle internal system space is small, and structure is complicated, and magnet and Hall chip arrangement difficulty are high, brake system interior section part material
Belong to permeability magnetic material, be affected to magnetic field of magnets, and then causes built-in Hall displacement sensor detection accuracy not high.Cause
This, currently used for the Hall sensor that detects brake pedal displacement, that there are detection accuracy is lower, sensor arrangement difficulty is high
Problem, is badly in need of researching and developing a kind of detection accuracy that can promote sensor and amplitude peak promotion sensor effectively measures stroke,
Facilitate the external hall displacement transducer of arrangement.
Summary of the invention
In view of the above-mentioned problems existing in the prior art, the task of the present invention is propose a kind of external Hall displacement sensing
Device, external hall displacement transducer of the invention, had not only improved the detection accuracy of sensor, but also significantly expand sensor
Effectively measurement stroke;Sensor is integrally external simultaneously, and installation is simple, and sensor self structure is simple, easy to maintain, and reduces
Magnet dosage, significantly reduces hall displacement transducer manufacturing cost.
To achieve the goals above, a kind of external hall displacement transducer provided by the invention, specific technical solution
It is as follows:
A kind of external hall displacement transducer, including magnetic group, magnetic group retainer, the PCB component with Hall chip and
Ontology, the magnetic group are made of 3 pieces of square magnets, and the magnetic group retainer both ends are provided with guiding deck, and upper end is provided with three
A magnet mounting groove, the retainer are made of non-magnet material;The body interior is provided with and magnetic group retainer guide card
The guide channel of seat cooperation, top are provided with the groove cooperated with the PCB component with Hall chip;The magnetic group retainer with
It can mutually be slided between ontology, the magnetic group square magnet upper surface and the Hall core on the PCB component with Hall chip
Piece end face is parallel, and keeps face, the magnetic group magnetic pole side vertically Hall chip, and the adjacent side of magnetic group in vertical direction
Shape magnet poles reversed arrangement.
External hall displacement transducer of the present invention, as shown in Fig. 2, being tested through 3D magnetic field simulation, by muti-piece side
The magnetic group of shape magnet composition, when magnetic group adjacent prismatic magnet poles reversed arrangement, magnetic field magnetic line angle change is fast, and magnetic field
Magnetic line of force angle change right above magnetic pole is most obvious, therefore, this side up arrangement Hall chip, sensor detection accuracy is most
It is high.Meanwhile being tested through 3D magnetic field simulation, under conditions of guaranteeing that effective travel is constant, when magnetic group internal magnet quantity is two pieces,
Hall displacement transducer detection accuracy is without being obviously improved;When magnetic group internal magnet quantity is 3 pieces, hall displacement transducer detection essence
Degree is substantially improved, but other than the magnetic blow out centre position of both ends, since magnetic direction is identical, which is measurement blind area, therefore
Stroke is effectively to measure stroke, and effective measurement stroke has fully met brake system check bit between the both ends magnetic blow out centre
Move measurement demand.It when magnetic group internal magnet quantity is greater than three pieces, is tested through 3D magnetic field simulation, effectively measures stroke and three pieces
It when magnet, effectively measures stroke and is consistent, therefore magnetic group continues growing magnet quantity, can not increase effectively measurement stroke.
External hall displacement transducer of the present invention, sensor is integrally external, by magnetic group retainer and needs
The moving component for measuring displacement is connected, and moving component moves left and right in ontology guide groove with magnetic group retainer and magnetic group,
Hall chip on PCB component with Hall chip perceives point changing magnetic field angle, on Hall chip and PCB component
Changing magnetic field angular transition can be corresponding electric signal by other electronic components, to obtain the relative displacement of moving component
Amount.External hall displacement transducer is lower to brake system internal space requirements, and arrangement is more flexible, meanwhile, Hall displacement
Sensor has a style of one's own, and Hall sensor internal magnetic field not will receive brake system inner body Effect of Materials, in brake system
The components material type selecting such as portion's push rod is more flexible.
Further, in order to reduce influence of the temperature to magnetic field strength, detection accuracy is promoted, it is described with Hall chip
Hall chip on PCB component is three axis Hall chips.
Further, it in order to increase the functional reliability of hall displacement transducer, prevents because of hall sensing component in PCB
Damage, cause sensor function to fail, the Hall chip on the PCB component with Hall chip be two-way Hall core
Piece.
Further, in order to reach maximum effective measurement stroke, the magnetic group square magnet shape is rectangle.
Further, in order to reduce cost, hall displacement transducer is more easily assembled, the magnetic group retainer is by moulding
Material is made, and the magnetic group square magnet is moulded in magnetic group retainer.
Further, the magnetic group retainer shape is cylindrical body, and the magnetic group retainer cylindrical body outer circumference surface is to lead
To deck, the body interior is provided with cylindrical hole, and the cylindrical hole of the body interior setting is and magnetic group retainer guide card
The guide channel of seat cooperation.
Compared with prior art, the beneficial effects of the present invention are:
1, a kind of external hall displacement transducer of the invention, had not only improved the detection accuracy of sensor, but also significantly
It expands sensor and effectively measures stroke;Structure is simple simultaneously, easy to maintain, reduces magnet dosage, significantly reduces Hall
Displacement sensor cost;
2, a kind of external hall displacement transducer of the invention, hall displacement transducer has a style of one's own, to brake system
Internal space requirements are lower, and installation is more flexible, meanwhile, Hall sensor internal magnetic field not will receive brake system inner body
Effect of Materials, the components material type selecting such as brake system inside push rod are more flexible;
3, a kind of external hall displacement transducer of the invention, magnetic group square magnet upper surface with Hall chip
Hall chip end face on PCB component is parallel, and keeps face up and down;Meanwhile magnetic group magnetic pole side vertically Hall chip,
And adjacent prismatic magnet poles reversed arrangement, the detection accuracy of sensor is improved to greatest extent.
Detailed description of the invention
Fig. 1 is two pieces of magnet Hall benefit magnetic field magnetic line schematic diagrames;
Fig. 2 is a kind of external hall displacement transducer magnetic field magnetic line schematic diagram of the invention;
Fig. 3 is a kind of external hall displacement transducer schematic diagram of the invention;
Fig. 4 is the top view of Fig. 3;
Fig. 5 is cross-sectional view of the Fig. 3 along line A-A;
Fig. 6 is cross-sectional view of the Fig. 5 along line B-B;
Fig. 7 is a kind of external hall displacement transducer axis side structure schematic diagram of the invention.
PCB component, 4- ontology, 5- groove, 6- installation with Hall chip of 1- magnetic group, 2- magnetic group retainer, 3- in figure
Slot, 7- circumferential apertures, 8- deck.
Specific embodiment
Any feature disclosed in this specification unless specifically stated can be equivalent or with similar purpose by other
Alternative features are replaced;That is, unless specifically stated, each feature is an example in a series of equivalent or similar characteristics
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Specific embodiments of the present invention will be described in detail with reference to the accompanying drawings and embodiments.
Embodiment 1
As illustrated in figs. 2-7, a kind of external hall displacement transducer of the present embodiment, including magnetic group 1, magnetic group retainer 2,
PCB component 3 and ontology 4 with Hall chip, the magnetic group 1 are made of 3 blocks of rectangle magnet, 2 shape of magnetic group retainer
Shape is cylindrical body, and 2 cylindrical body excircle of magnetic group retainer is guiding deck 8, and middle part is provided with through slot, and through slot bottom surface is provided with three
A rectangle magnet mounting groove 6, the retainer are made of plastics;The ontology 4 is internally provided with to be oriented to magnetic group retainer 2
The cylindrical hole 7 that deck 8 cooperates, top are provided with the groove 5 cooperated with the PCB component 3 with Hall chip;It is described to have Hall
Hall chip on the PCB component 3 of chip is three axis two-way Hall chips;It being capable of phase between the magnetic group retainer 2 and ontology 4
Mutually sliding, the 1 rectangle magnet upper surface of magnetic group is parallel with the Hall chip end face on the PCB component 3 with Hall chip,
And face is kept in the vertical direction, the 1 magnetic pole side of magnetic group vertically Hall chip, and the adjacent rectangle magnetic of magnetic group 1
Magnetic pole iron reversed arrangement.
Embodiment 2
As illustrated in figs. 2-7, a kind of external hall displacement transducer of the present embodiment, including magnetic group 1, magnetic group retainer 2,
PCB component 3 and ontology 4 with Hall chip, the magnetic group 1 are made of 3 blocks of rectangle magnet, 2 shape of magnetic group retainer
Shape is cylindrical body, and 2 cylindrical body excircle of magnetic group retainer is guiding deck 8, is provided in the middle part of 2 cylindrical body of magnetic group retainer logical
Slot, the retainer are made of plastic injection, and 3 blocks of rectangle magnet of the magnetic group are moulded in through slot bottom surface in magnetic group retainer;
The ontology 4, which is internally provided with, is oriented to the cylindrical hole 7 that deck 8 cooperates with magnetic group retainer 2, and top is provided with and has Hall core
The groove 5 that the PCB component 3 of piece cooperates;Hall chip on the PCB component 3 with Hall chip is three axis two-way Halls
Chip;Can mutually be slided between the magnetic group retainer 2 and ontology 4, the 1 rectangle magnet upper surface of magnetic group with suddenly
Hall chip end face on the PCB component 3 of your chip is parallel, and keeps face in vertical direction, and the 1 magnetic pole side of magnetic group is hung down
Directly towards Hall chip, and the adjacent rectangle magnet poles reversed arrangement of magnetic group 1.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention
Made any modifications, equivalent replacements, and improvements etc., should all be included in the protection scope of the present invention within mind and principle.