CN102393208A

CN102393208A - Mile detection device

Info

Publication number: CN102393208A
Application number: CN2011103219869A
Authority: CN
Inventors: 何友国; 周勇
Original assignee: SAIC Chery Automobile Co Ltd
Current assignee: Chery Automobile Co Ltd
Priority date: 2011-10-20
Filing date: 2011-10-20
Publication date: 2012-03-28

Abstract

The invention relates to metering detection of vehicle driving miles, and provides a detection device. The detection device comprises two Hall sensors; the Hall sensors correspond to adjacent two addendums; when a gear ring rotates, at least one addendum is in the measuring range of the combination comprising the Hall sensors; and the Hall sensors conduct metering by collecting and outputting pulse signals to control a circuit. Through the Hall sensors calculating the vehicle driving miles, irregular pulse signals generated when a vehicle is parked in a critical detection position of the Hall sensors are eliminated; possible error of driving mile calculation is avoided; and the accuracy of the vehicle driving mile calculation is improved.

Description

The mileage pick-up unit

Technical field

The present invention relates to the Measuring and testing of VMT Vehicle-Miles of Travel.

Background technology

In the prior art; VMT Vehicle-Miles of Travel can detect through wheel speed sensors, and is concrete, gear ring is fixed on the wheel hub rotates synchronously with wheel; Wheel speed sensors is installed in the wheel relevant position and wheel speed sensors does not rotate with wheel, and wheel speed sensors and gear ring are non-contact detection; Wheel speed sensors comprises electromagnetic type speed probe and Hall wheel speed sensors, is that example describes with the Hall wheel speed sensors below.

As shown in Figure 1; In the process of gear ring with wheel; The tooth top of gear ring and backlash replace the Hall element through wheel speed sensors; The magnetic line of force power of passing Hall element changes with the rotation of gear ring, in the gear ring rotation process, has caused the variation of Hall voltage and the voltage signal that the output quasi sine distributes like this, converts the pulse voltage that high-low level replaces to through electronic circuit; , can carry out the calculating of operating range according to predetermined strategy and show operating range as the motion of output drive stepping motor with this pulse voltage.

Concrete, when the position is through Hall element near tooth top, passes the magnetic line of force of Hall element and concentrate, its magnetic field intensity is stronger relatively, the high level signal in the voltage pulse output, promptly near the position of tooth top is within the sensing range of Hall element; When near the position backlash when the Hall element, the magnetic line of force that passes Hall element disperses, its magnetic field intensity relatively a little less than, the low level signal in the voltage pulse output, promptly the position exceeds the sensing range of Hall element near the backlash.It is understandable that, on gear ring, have critical localisation with respect to the Hall element sensing range, within the scope of this critical localisation near tooth top, Hall element output high level signal; In the scope of this critical localisation near backlash, Hall element output low level signal.

As depicted in figs. 1 and 2, dotted line is represented the detection distance of Hall element 100 among the figure.Concrete, as shown in Figure 1 when the tooth top 210 of gear ring 200 turns to the correspondence position with the Hall element of Hall wheel speed sensors 100, in the sensing range of Hall element 100, export high level signal; When the backlash 220 of gear ring 200 turns to the correspondence position with the Hall element of Hall element 100, as shown in Figure 2, backlash 220 this moment output low level signal in the sensing range of Hall element 100 not; Thereby, the pulse voltage signal of wheel speed sensors 100 output high-low level alternate in gear ring 200 rotation processes.

In the vehicle parking process; The path of parking that needs the control vehicle with steering wheel angle so that vehicle parking arrives corresponding parking place; If the critical localisation of its gear ring 200 is over against Hall element 100 during vehicle parking; As shown in Figure 3, promptly vehicle parking is at the detection critical localisation point of Hall element 100 on gear ring 200; At this moment, the pulse signal of Hall element output is irregular, and with respect in normal pulse signal, having clutter, this pulse signal possibly cause mistake to be calculated in vehicle driving mileage computation process, thereby it is inaccurate that VMT Vehicle-Miles of Travel is calculated.

VMT Vehicle-Miles of Travel calculates the degree of accuracy that influences calculating of vehicle parking path simulation and steering wheel angle signal controlling, can cause vehicle not have like this and moor corresponding parking place; And in the prior art, can't eliminate to the irregular pulse signal that vehicle parking produces when Hall element detects critical localisation.

Summary of the invention

The object of the invention just provides a kind of mileage pick-up unit, is used to eliminate the irregular pulse signal that vehicle parking produces when Hall element detects critical localisation, avoids erroneous calculations, improves the accuracy that VMT Vehicle-Miles of Travel calculates.

For realizing above-mentioned purpose; The present invention adopts following technical scheme: a kind of mileage pick-up unit; It is characterized in that: pick-up unit comprises two Hall elements; Arranging of said two Hall elements corresponding to adjacent two tooth tops, and gear ring when rotating at least one tooth top be positioned at the multiple measurement scope that two Hall elements constitute, described Hall element collection and output pulse signal control circuit measure.

The present invention calculates VMT Vehicle-Miles of Travel through two Hall elements are installed; Eliminated the irregular pulse signal that vehicle parking produces when Hall element detects critical localisation; Avoid distance travelled to calculate issuable mistake, improved the accuracy that VMT Vehicle-Miles of Travel calculates.

Summary of drawings

Fig. 1,2, the 3rd, the measurement mechanism structural representation of prior art;

Fig. 4 is a structural representation of the present invention.

Embodiment

In conjunction with shown in Figure 4; The mileage pick-up unit comprises two Hall elements 10,20; Said two Hall elements 10,20 are arranged corresponding to adjacent two tooth tops 31,32; And at least one tooth top was positioned at the multiple measurement scope that two Hall elements 10,20 constitute when gear ring 30 rotated, and described Hall element collection and output pulse signal control circuit measure.In other words; Each Hall element has certain measurement orientation; The measured zone of two Hall elements should UNICOM and situation about leaving mutually occurs; Guarantee that measurement range is not interrupted, more specifically say preferred scheme be exactly the multiple measurement scope that constitutes of described two Hall elements 10,20 for occuring simultaneously, can guarantee that like this phenomenon of meter does not appear leaking in mileage.

As preferred version; Described two Hall elements are same model; Disposed at equal distance is convenient to fitting operation like this at the gear ring side, saves the installing space of Hall element simultaneously and arranges; And the sensor of same model can obtain the identical detection distance and the consistance of sampled signal, makes things convenient for the post-processed of control circuit.

The detection distance of described sensor and the intersection point of adjacent tooth top the horizontal range M of backlash side less than, equal the horizontal range N between the Hall element, practical implementation can be selected following scheme for use: the detection distance of described sensor and the intersection point of adjacent tooth top the horizontal range M of backlash side less than and near the horizontal range N between the Hall element.So both guarantee the reliability of signals collecting, be beneficial to spatial placement simultaneously.

Core concept of the present invention is; Two Hall elements are installed in the pick-up unit in system, and the Hall element of said two Hall elements is corresponding to gear ring, at gear ring during with wheel; Two sensors detect and output pulse signal simultaneously; The irregular pulse signal of having avoided when a sensor correspondence and gear ring critical localisation, producing is exported, and avoids erroneous calculations, improves the accuracy that VMT Vehicle-Miles of Travel calculates.

As shown in Figure 4; The structural representation of the anti-error computing system of a kind of mileage that proposes for the embodiment of the invention; Dotted line L representes the detection distance of two sensors among the figure, sensor near tooth top near in the distance of position, two sensors output high level signal; Sensor near backlash near in the distance of position, two sensors output low level signal.

Whether a little error of mileage metering does not generally have adverse effect to vehicle ', and for the state of parking, will influence vehicle can realize parking, and the present invention can realize accurately measuring distance travelled, guarantees that the vehicle pool stops to corresponding position.

During practical implementation, have following two kinds of schemes available, the center position of described two the Hall element search coverages of the first points to gear ring center; It two is parallel sensing gear ring center one sides of center position of described two Hall element search coverages and equates with gear ring center distance.The arrangement of these two kinds of sensors can guarantee each sensor acquisition to signal have consistance, be convenient to the identification and the processing of processing unit, guarantee the accuracy and the reliability of mileage metering.

Claims

1. mileage pick-up unit; It is characterized in that: pick-up unit comprises two Hall elements; Said two Hall elements are arranged corresponding to adjacent two tooth tops; And at least one tooth top was positioned at the multiple measurement scope that two Hall elements constitute when gear ring rotated, and described Hall element collection and output pulse signal control circuit measure.

2. mileage pick-up unit according to claim 1 is characterized in that: described two Hall elements are same model, and disposed at equal distance is at the gear ring side.

3. mileage pick-up unit according to claim 1 is characterized in that: the multiple measurement scope that described two Hall elements constitute is for occuring simultaneously.

4. according to claim 1 or 2 or 3 described mileage pick-up units, it is characterized in that: the detection distance of described sensor and the intersection point of adjacent tooth top the horizontal range M of backlash side less than, equal the horizontal range N between the Hall element.

5. mileage pick-up unit according to claim 2 is characterized in that: the center position of described two Hall element search coverages points to gear ring center.

6. mileage pick-up unit according to claim 2 is characterized in that: parallel sensing gear ring center one side of the center position of described two Hall element search coverages and equate with gear ring center distance.

7. mileage pick-up unit according to claim 4 is characterized in that: the detection distance of described sensor and the intersection point of adjacent tooth top the horizontal range M of backlash side less than and near the horizontal range N between the Hall element.