CN102353488A

CN102353488A - Torque sensor

Info

Publication number: CN102353488A
Application number: CN2011101566291A
Authority: CN
Inventors: 王成
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-06-10
Filing date: 2011-06-10
Publication date: 2012-02-15

Abstract

The invention discloses a torque sensor, so that a defect of low measuring precision of a torque sensor in the prior art can be overcome. The torque sensor is characterized in that: a shell is in a cylinder shape and is hollow inside; two sets of induction coils are parallel mutually and are sleevedly installed in the shell separately; magnetic shields are sleevedly installed at an innermost layer of the shell; two sets of induction ports are respectively arranged at positions where the magnetic shields are corresponded to the two sets of the induction coils; the two sets of the induction ports are formed by a plurality of induction openings that are mutually independent and are paved and arranged with a certain interval along induction surfaces of the induction coils; and the induction openings in the two sets of the induction ports are in staggered arrangements along a longitudinal axial direction of each the magnetic shield. Twisting movements of a twist spindle enable inductances in the corresponded induction coils to be changed through the two sets of the induction ports; and terminals on the shell transmit a differential value of inductances in the two sets of the induction coil to an external controller. According to the invention, the employed shell is manufactured by an iron-based powder metallurgy functional material and thus, the shell is not sensitive to a temperature and an external interference; and the torque sensor has advantages of high reliability as well as a sturdy and durable performance. Meanwhile, a measuring precision is improved and the stability is strengthened.

Description

A kind of torque sensor

Technical field

The present invention relates to a kind of torque sensor, particularly a kind of sensor that the moment of torsion that produces because of twisting force in the motor turning process is carried out sensing.

Background technology

Torque sensor is an ingredient of EPS (Electronic Power Steering) system; Although the structure member of its EPS system of different automobiles is different; But each building block still duplicates substantially; The powered assistance motorist that the EPS system mainly utilizes motor to produce carries out turning to of power; Therefore, torque sensor is exactly wherein requisite parts.

The used torque sensor of EPS system can be divided into contact and contactless, and main utilization is turned round axle torque conversion is become twisting stress or torsion angle, converts the electric signal that becomes certain relation with torque again to, transmits through sensor.The form of turning round axle has solid shaft, tubular shaft, rectangular shaft etc.

The torque sensor major part of existing application on automobile is touch sensor, though simple in structure, easily manufactured, because of using conducting slip ring, vibration frequency is lower, is inappropriate for the high-speed rotary body occasion bigger with turning round shaft vibration and uses; Because the friction between measurement axis and the slip ring also is easy to generate measuring error, measuring accuracy can not effectively be ensured simultaneously.

Summary of the invention

The objective of the invention is to disclose a kind of torque sensor, to solve the not high defective of existing torque sensor measuring accuracy.

In order to realize above purpose; Torque sensor of the present invention; Comprise shell, two groups of induction coils and magnetic shield; Shell is the cylindric of inner hollow; Two groups of induction coils be parallel to each other and the suit of isolating in the enclosure; Magnetic shield is sleeved on the innermost layer of shell; Magnetic shield is respectively arranged with two groups of sensor port with two groups of corresponding positions of induction coil; Two groups of sensor port are arranged along the sensitive surface tiling of induction coil with certain interval by several separate induction mouths; Induction mouth in two groups of sensor port is staggered along longitudinal center's axis direction of magnetic shield; The twisting of turning round axle causes the variation of corresponding induction coil internal electrical sensibility reciprocal by two groups of sensor port; The outer end of shell is provided with the terminal that links to each other with peripheral control unit, and torque sensor is sent to peripheral control unit by terminal with the difference of inductance value in two groups of induction coils.

Preferably, also be provided with two groups of coil racks, two groups of corresponding settings of coil rack with inductive coil, the outside surface that is coated on inductive coil that coil rack is adaptive, in the enclosure nested behind the inductive coil suit coil skeleton.

Preferably, the skin of inductive coil also is coated with the insulation gummed paper, and the insulation gummed paper is encapsulated in coil rack inside with inductive coil insulation.

Preferably, shell adopts the ferrous based powder metallurgical functional material to process.

Torque inductor of the present invention, shell adopt the ferrous based powder metallurgical functional material to process, and be insensitive to temperature and external interference, and reliability is high, and is sturdy and durable, improved measuring accuracy simultaneously, and stability is stronger.

Description of drawings

Fig. 1 is the stereographic map of torque inductor of the present invention;

Fig. 2 is first longitdinal cross-section diagram of torque inductor of the present invention;

Fig. 3 is second longitdinal cross-section diagram of torque inductor of the present invention;

Fig. 4 is the cut-open view of torque inductor of the present invention.

In conjunction with the accompanying drawing following Reference numeral of mark thereon:

The 1-shell, the 2-magnetic shield, 3-first inductive coil, the 4-coil rack, the 5-terminal, 6-turns round axle, 7-second sensor port, 8-first sensor port, 9-ferrous based powder metallurgical functional material, the 10-gummed paper that insulate, 11-second inductive coil, 12-is protruding.

Embodiment

Below in conjunction with accompanying drawing, specific embodiments of the invention is described in detail.

A kind of torque sensor is disclosed like Fig. 1-shown in Figure 4; Comprise shell 1, two groups of induction coils and magnetic shields 2; Shell 1 is the cylindric of inner hollow; Two groups of induction coils comprise first induction coil 3 and second induction coil 11; First induction coil 3 and second induction coil 11 are parallel to each other is coated on shell 1 inside; First induction coil 3 and second induction coil, 11 inner coils all have electric current to insert; Thereby can produce certain inductance; First induction coil 3 and second induction coil 11 are mutually insulateds; The innermost layer of shell 1 is set with magnetic shield 2; The magnetic shield 2 general aluminium that adopt are made; The internal sleeve of magnetic shield 2 is equipped with the axle 6 of turning round to be detected; Magnetic shield 2 be provided with two groups of sensor port with two groups of corresponding positions of induction coil; Promptly be respectively arranged with first sensor port 8 and second sensor port 7 with first induction coil 3 and second induction coil, 11 corresponding positions; First sensor port 8 and second sensor port 7 are by several inductions mouthful composition of isolating each other; Spacing between the induction mouth of every group of sensor port inside is fixed; Simultaneously; Each induction mouth of first sensor port 8 is to arrange along the sensitive surface tiling of first induction coil 3; Second sensor port 7 is to be arranged in a combination by each induction mouthful sensitive surface tiling along second induction coil 11; The induction mouth of the induction mouth of first sensor port 8 and second sensor port 7 is interlaced settings in longitudinal center's axis direction of magnetic shield 2; In brief, the induction mouth in first sensor port 8 and second sensor port 7 is can not be on the same longitudinal axis.Like this; When turning round axle 6 and be subjected to twisting force to produce deflection; This deflection causes the variation that first induction coil 3 and second induction coil, 11 two ends produce inductance value by first sensor port 8 on the magnetic shield 2 and second sensor port 7 respectively; The difference of the inductance value between first induction coil 3 and second induction coil 11 will directly reflect the size of the moment of torsion of turning round axle 6; Because the outer surface of shell 1 also is connected with terminal 5; Terminal 5 links to each other with peripheral control unit again; Therefore; The inductance difference of reaction torque size is just passed to peripheral control unit by terminal 5, and peripheral control unit is further judged the power-assisted of reversing of correspondence that needs provide according to torque.

Because of turn round the axle 6 in operation process often temperature can change; And variation of temperature can have influence on the variation of the inductance value of inductive coil; The size that receives the moment of torsion that inductive coil reacted after the external interference also has bigger error certainly, and measuring also can be as sensitive originally.For addressing this problem, like Fig. 2-shown in Figure 4, the present invention adopts ferrous based powder metallurgical functional material 9 to process shell 1, and this material has reduced the influence of extraneous factors such as temperature to test result accordingly to temperature-insensitive, and test result is more accurate.

Simultaneously; For better insulating and the protection coil; The present invention also is provided with insulation gummed paper 10 and coil rack 4; Insulation gummed paper 10 is coated on the skin of first inductive coil 3 and second inductive coil 11; First inductive coil 3 and second inductive coil 11 are isolated with exterior insulation; First inductive coil 3 and second inductive coil 11 that are coated with insulation gummed paper 10 are set in two coil rack 4 inside again; Coil rack 4 can better be coated and fixed first inductive coil 3 and second inductive coil 11; Make itself and external isolation; Increase the service life, increase the sensitivity of test.

The application's concrete principle of work and process are such: turn round on axle 6 the axial end and be respectively equipped with a plurality of protruding 12 with first sensor port 8 and second sensor port, 7 corresponding positions; Protruding 12 are generally all processed by metal material; When protruding 12 aim at sensor port; The inductance value at inductive coil two ends is maximum; Accordingly; When protruding 12 departed from sensor port, the inductance value at inductive coil two ends will reduce.Because the position of first sensor port 8 and second sensor port 7 is interlaced; When turning round axle 6 when reversing; The protruding 12 position distances with respect to first sensor port 8 are different with the protruding 12 position distances with respect to second sensor port 7; That is to say that protruding 12 electromagnetic induction that cause through first sensor port 8 and second sensor port 7 there are differences; The inductance value at such first inductive coil 3 and second inductive coil, 11 two ends will there are differences, and the difference of two groups of inductive coil two ends inductance values is just reacted the torque of turning round axle 6.

Torque inductor of the present invention, shell adopt the ferrous based powder metallurgical functional material to process, and be insensitive to temperature and external interference, and reliability is high, and is sturdy and durable, improved measuring accuracy simultaneously, and stability is stronger; Inductive coil is sleeved on again in the coil rack after being covered by the insulating gel paper bag, the insulation degree is higher, has not only increased the levels of precision of test, can also effectively protect inductive coil, thereby prolong serviceable life of torque inductor.

More than disclosed only be several specific embodiment of the present invention, still, the present invention is not limited thereto, any those skilled in the art can think variation all should fall into protection scope of the present invention.

Claims

1. torque sensor; It is characterized in that; Comprise shell, two groups of induction coils and magnetic shield; Said shell is the cylindric of inner hollow; What two groups of said induction coils were parallel to each other and isolated is sleeved in the said shell; Said magnetic shield is sleeved on the innermost layer of said shell; Said magnetic shield is respectively arranged with two groups of sensor port with two groups of corresponding positions of induction coil; Two groups of said sensor port are arranged along the sensitive surface tiling of said induction coil with certain interval by several separate induction mouths; Induction mouth in two groups of said sensor port is staggered along longitudinal center's axis direction of said magnetic shield; The twisting of turning round axle causes the variation of corresponding induction coil internal electrical sensibility reciprocal by two groups of said sensor port; The outer end of said shell is provided with the terminal that links to each other with peripheral control unit, and said torque sensor is sent to peripheral control unit by said terminal with the difference of inductance value in two groups of induction coils.

2. torque sensor according to claim 1; It is characterized in that; Also be provided with two groups of coil racks; Two groups of corresponding settings of said coil rack with inductive coil; The outside surface that is coated on said inductive coil that said coil rack is adaptive is nested in the said shell behind the said coil rack of said inductive coil suit.

3. torque sensor according to claim 2 is characterized in that the skin of said inductive coil also is coated with the insulation gummed paper, and said insulation gummed paper is with the said coil rack of being encapsulated in of said inductive coil insulation inside.

4. according to any described torque sensor among the claim 1-3, it is characterized in that said shell adopts the ferrous based powder metallurgical functional material to process.