KR20100000986A - Non-contacting type torque sensor for steering system - Google Patents

Abstract

PURPOSE: A contactless torque sensor for a steering apparatus is provided to detect twist from changes in the magnetic force when a rotational angle difference occurs due to the twist of an output shaft connected to wheels. CONSTITUTION: A contactless torque sensor for a steering apparatus comprises a magnetic force generation part(110) in which N-pole and S-pole magnets(114,115) are arranged alternately, a magnetic flux shield part(120) which is connected to an output shaft(20) and has a plurality of holes(121,122) in which the N-pole and the S-pole magnets are placed, a magnetic flux detecting part(130) which is installed separate from the outer surface of the magnetic flux shield part and detects the magnetic flux passing through the holes, and a magnetic force sensing part(140) which is formed on the outer surface of the magnetic flux shield part and detects changes in relative twisting of the magnetic flux shield part and the magnetic force generation part.

Description

Non-contact torque sensor for steering system {NON-CONTACTING TYPE TORQUE SENSOR FOR STEERING SYSTEM}

The present invention relates to a non-contact torque sensor for a steering apparatus, and more particularly, when the input shaft is rotated by the steering wheel, the output shaft connected to the wheel can be rotated in the same manner as the input shaft to improve steering force. A non-contact torque sensor for an apparatus.

In general, as the steering wheel is rotated when the vehicle is driven or stopped, the wheels in contact with the road surface are also rotated. That is, when the steering wheel is rotated in the left direction or the right direction, the wheel rotates in the same direction. However, since the wheels are in contact with the road surface, the rotation ratios of the steering wheel and the wheels are different from each other by the friction force between the wheels and the road surface, so that the driver needs a large force to operate the steering wheel. do.

Accordingly, a torque sensor is provided to measure a rotation angle deviation between the steering wheel and the wheel and compensate for the deviation. That is, the torque sensor may measure the angle of rotation of the steering wheel and the wheel, and may safely and accurately steer the vehicle in the desired direction by rotating the wheel by using a separate power means by the measured deviation. It is a device for enhancing steering convenience.

The torque sensor is largely classified into a contact method and a non-contact method, and the contact method has recently adopted a non-contact torque sensor due to noise and deterioration of durability. In addition, the non-contact torque sensor is largely divided into a magnetoresistance detection method, a magnetostriction detection method, a capacitance detection method, and an optical detection method.

On the other hand, the torque sensor of the magnetoresistive detection method provided in the conventional electric power steering device, the steering wheel handled by the driver is coupled to the upper end of the input shaft, the lower end of the input shaft to the torsion bar (Torsion bar) Is connected to the top of the output shaft. The lower end of the output shaft is connected to a wheel, and the lower end of the input shaft including the torsion bar and the upper end of the output shaft are protected by a housing. In addition, the aforementioned torque sensor and power means are installed in the housing.

Here, the input shaft is provided with a permanent magnet having a polarity crossing at regular intervals.

The detection ring of the gear structure corresponding to the number of poles of the permanent magnet is installed on the output shaft as a ferromagnetic material capable of generating magnetic induction by the permanent magnet provided on the input shaft. The detection ring has a structure in which a sensor for detecting magnetism is connected.

Therefore, when the driver manipulates the steering wheel, the rotational force is transmitted to the input shaft, and the torsion bar is rotated by the rotation of the input shaft. In addition, since the torsion bar is also connected to the output shaft, the torsion bar transmits rotational force to the output shaft, and the wheel is turned in the direction in which the steering wheel is operated.

At this time, the area corresponding to each other is changed by the relative twist between the permanent magnet installed on the input shaft and the detection ring of the gear structure provided on the output shaft. Accordingly, a change in magnetic force is generated in the detection ring, and the sensor detects the change in the magnetic force so that the output shaft detects an angle in which a twist occurs with respect to the input shaft.

However, the conventional torque sensor made as described above has a structure in which the detection ring continuously rotates around the sensor, and the magnetic force formed from the permanent magnet is severely changed, and the rotation of the detection ring and the magnetic detection element There was a problem that a fixed detection ring must be additionally installed to avoid interference.

However, when the fixed detection ring is additionally installed, the magnetic force generated in the permanent magnet is first induced through the detection ring and then magnetically induced through the fixed detection ring. As the magnetic force decreases while passing through, there is a problem that it is impossible to detect an accurate twist of the input shaft and the output shaft.

An object of the present invention for solving the above problems is to provide a non-contact torque sensor for a steering apparatus that can detect the torsion angle of the output shaft by only one magnetic induction without undergoing a secondary induction process.

The present invention provides a non-contact torque sensor for a steering apparatus that detects a torsion by a change in magnetic force when a difference in a rotation angle due to a torsion of an output shaft connected to a wheel is generated according to a change in rotation of an input shaft rotated by a handle.

The non-contact torque sensor for a steering apparatus of the present invention for achieving the above object is provided between the input shaft connected to the handle of the vehicle and the output shaft connected to the wheel of the vehicle to detect the torsion generated by the rotation operation of the handle. A non-contact torque sensor for steering apparatus, comprising: a magnetic force generating unit coupled to the input shaft and having a plurality of N pole magnets and S pole magnets alternately disposed along an outer circumferential surface thereof so as to have the same radius at a center thereof; A magnetic shield having a cylindrical shape and connected to the output shaft and having a plurality of holes formed in the plurality of N-pole and S-pole magnets, respectively; A magnetic detection unit provided to be spaced apart from an outer circumferential surface of the magnetic shield and detecting a magnetic force passing through the plurality of holes; And a magnetic detection sensor unit disposed on an outer circumferential surface of the magnetic detection unit to sense a relative torsional change in the magnetic force generating unit and the magnetic shielding unit.

In the non-contact torque sensor for steering device of the present invention, the magnetic force generating portion is coupled to the lower end of the input shaft; And a magnet fixing part having a cylindrical shape located below the coupling part, wherein a plurality of the N pole magnets and the S pole magnets are coupled to an outer circumferential surface of the magnet fixing part.

In the non-contact torque sensor for a steering apparatus of the present invention, the magnetic shield includes: a first magnetic shield including a plurality of first holes formed at regular intervals on the upper outer circumferential surface; And a second magnetic shield formed on the lower outer circumferential surface of the first magnetic shield at regular intervals, the second magnetic shield including a second through hole that is alternately disposed with the first through hole.

In the non-contact torque sensor for steering apparatus of the present invention, when the output shaft is rotated in the same manner as the input shaft so that the twist angle is "0", the boundary between the N pole magnet and the S magnet is located at the vertical center of the hole.

In the non-contact torque sensor for a steering apparatus according to the present invention, when the output shaft has a maximum torsion in a left or right direction with respect to the input shaft, any one of the S and N pole magnets is provided through a plurality of the first through holes. The magnet is exposed, and another magnet is exposed through the plurality of second through holes.

In the non-contact torque sensor for steering apparatus of the present invention, the plurality of first through holes and the second through holes each have a shape having an area of the same hole.

In the non-contact torque sensor for steering apparatus of the present invention, the top height of the N-S pole magnet and the magnetic detection part is the same as the top height of the first through hole, and the bottom height of the N-S pole magnet and the magnetic detection part is It is located at the same height as the bottom of the second through-hole.

In the non-contact torque sensor for a steering apparatus according to the present invention, the top heights of the N-S pole magnets and the magnetic detection portion are located differently from the top heights of the first through-holes, and the lower ends of the N-S pole magnets and the magnetic detection portions. The height is different from the bottom height of the second through hole.

A non-contact torque sensor for a steering apparatus according to the present invention, the magnetic detection unit comprising: a first magnetic detection member for detecting a magnetic force passing through the first through hole; And a second magnetic detection member positioned to be spaced below the first magnetic detection member and detecting a magnetic force passing through the second through hole.

In the non-contact torque sensor for a steering apparatus of the present invention, the magnetic detection unit includes: a first collector ring provided on an outer circumferential surface of the first magnetic detection member to maximize the magnetic force induced from the magnetic force generation unit; And a second dust collector ring provided on an outer circumferential surface of the second magnetic detection member.

In the non-contact torque sensor for a steering apparatus of the present invention, at least one magnetic detection sensor unit is connected to each of the first and second collector rings.

In the non-contact torque sensor for a steering apparatus of the present invention, the magnetic detection unit includes: a first protruding member protruding outward from an outer circumferential surface of the first dust collecting ring; And a second protrusion member protruding outward from an outer circumferential surface of the second dust collecting ring and positioned in the same vertical position as the first protrusion member, wherein the magnetic detection sensor unit includes the first protrusion member and the second protrusion. It is located between the members.

In the non-contact torque sensor for a steering apparatus of the present invention, the first protrusion member is provided in plural on the outer circumferential surface of the first collector ring, the second protrusion member is provided in plural on the outer circumferential surface of the second collector ring, Magnetic detection sensor units are respectively located between the plurality of first second protruding members.

In the non-contact torque sensor for a steering apparatus of the present invention, the magnetic shield part is manufactured in one piece with the first magnetic shield part and the second magnetic shield part.

In the non-contact torque sensor for a steering apparatus of the present invention, the N-pole and S-pole magnets are alternately arranged along an upper outer circumferential surface, and another S-pole magnet is disposed below the N-pole magnet, and disposed on an upper outer circumferential surface thereof. Another N pole magnet is disposed below the S pole magnet.

In the non-contact torque sensor for steering device of the present invention, the magnetic shield is disposed in the boundary between the N pole magnet and the S pole magnet disposed on the upper outer peripheral surface, and the N pole magnet and the S magnet disposed on the lower outer peripheral surface.

In the non-contact torque sensor for a steering apparatus according to the present invention having the above characteristics, the N-pole and S-pole magnets are alternately arranged on the outer circumferential surface of the input shaft, and the output shaft includes a magnetic shield having a plurality of holes. Therefore, when the output shaft is twisted with respect to the input shaft, the magnetic force of the N pole magnet and the S pole magnet passes through a plurality of holes formed in the magnetic shield, and the relative twist change is transmitted to the magnetic detection unit, thereby changing the magnetic force in the magnetic detection sensor unit. Torsion can be detected.

That is, the strength of the magnetic force of the N pole magnet and the S pole magnet through the plurality of holes varies according to the torsion angles of the input shaft and the output shaft. The strength of the magnetic force according to the torsion angle in the magnetic detection sensor unit is transferred to the magnetic detection unit. Will be detected.

In addition, the magnetic force induced through the first through holes provided on the upper side of the magnetic shield has polarity of the N pole magnet or the S pole magnet in the first magnetic detection member, and the second through holes provided below the magnetic shield. The induced magnetic force has a different polarity in the second magnetic detection member. Therefore, the left torsion and the right torsional change of the output shaft are sensed through the magnetic detection sensor unit.

In addition, it is possible to reduce the number of parts by improving the overall structure of the non-contact torque sensor for the steering device to reduce the manufacturing cost, it is also possible to shorten the manufacturing time by reducing the number of manufacturing processes.

Hereinafter, with reference to the accompanying drawings to explain the configuration and operation of the non-contact torque sensor 100 for the steering apparatus of the present invention.

As shown in FIGS. 1 to 3, the non-contact torque sensor 100 for the steering apparatus is largely composed of a magnetic force generating unit 110, a magnetic shielding unit 120, a magnetic detecting unit 130, and a magnetic detecting sensor unit 140. Is done. Here, the magnetic force generator 110 is connected to the input shaft 10 connected to the handle of the vehicle, the magnetic shield 120 is connected to the output shaft 20 connected to the wheel of the vehicle. In addition, the input shaft 10 and the output shaft 20 are connected by the torsion bar 30.

First, the insertion shaft 11 is formed at the lower end of the input shaft 10, and a connection groove 12 into which the upper end of the torsion bar 30 is inserted is formed in the insertion portion 11. In addition, the coupling hole 13 which is positioned above the insertion portion 11 and penetrates in the transverse direction is formed on the outer circumferential surface of the input shaft 10.

Here, the insertion part 11 provided in the input shaft 10 may vary depending on the shape of the magnetic force generating part 110 to be described later. That is, in the accompanying drawings, but the lower end of the input shaft 10 is inserted into the magnetic force generating unit 110, the upper end of the torsion bar 30 is inserted into the connecting groove 12 is shown as a structure coupled to the pin (40a). However, this structure is for explaining the preferred embodiment of the present invention, the connection state with the input shaft 10 may vary depending on the shape of the magnetic force generating unit (110).

The magnetic force generating unit 110 is composed of a coupling portion 112 and a magnet fixing portion 113 formed with a through hole 111 in the center, and a plurality of N pole magnets 114 and S pole magnets 115.

First, the coupling part 112 has a through hole 111 formed at the center of the coupling part 112 inserted into the insertion part 11 provided at the lower end of the input shaft 10. At this time, the insertion portion 11 and the coupling portion 112 may be coupled due to a plurality of fastening members (not shown), and the outer circumferential surface of the insertion portion 11 and the inner circumferential surface of the coupling portion 112 may be fastened with screws. .

And, the magnet fixing part 113 is located below the coupling part 112, the magnet fixing part 113 and the coupling part 112 may be formed integrally, the magnet fixing part 113 is in the center It is made in the shape of a cylinder to have the same radius.

In addition, the N-pole magnet 114 and the S-pole magnet 115 are each formed in plural and are located on the outer circumferential surface of the magnet fixing part 113. The N pole magnets 114 and the S pole magnets 115 are arranged to be staggered with each other, and the sum of the two magnets is necessarily an even number.

That is, when the number of N pole magnets 114 is eight, the number of S pole magnets 115 is also eight, and when there are nine N pole magnets 114, the number of S pole magnets 115 is also nine. In addition, the N pole magnet 114 and the S pole magnet 115 may be attached to the outer circumferential surface of the magnet fixing part 113 in a separated state, respectively, but the ferromagnetic material having no polarity may be attached to the magnet fixing part 113. After attaching to the magnets, the N-pole magnets 114 and the S-pole magnets 115 may be configured by dividing the regions so as to have the magnetic force of the N-pole and the S-pole when magnetized.

In the accompanying drawings, the number of N-pole magnets 114 and S-pole magnets 115 is illustrated as eight. However, the number of the N pole magnets 114 and the S pole magnets 115 may vary. The N pole magnets 114 and the S pole magnets 115 are provided such that the inner circumferential surface and the outer circumferential surface have the same thickness.

On the other hand, the magnetic shield 120 is located outside the magnetic force generating unit 110, it is divided into a first magnetic shield 120a and a second magnetic shield 120b. However, the first magnetic shield 120a and the second magnetic shield 120b are formed in a cylindrical shape integrally.

That is, the magnetic shield 120 is positioned to be spaced apart from the outer portions of the N pole magnet 114 and the S pole magnet 115 provided in the magnetic force generating unit 110, the lower end is connected to the output shaft 20 to be described later do. In the accompanying drawings, a separate connection member 150 is coupled to the lower side of the magnetic shield 120, and the output shaft 20 is coupled to the connection member 150.

In addition, a plurality of holes 121 and 122 are formed in the magnetic shield 120. The plurality of holes 121 and 122 may include a plurality of first through holes 121 and second through holes 122 so as to be located in the N pole magnets 114 and the S pole magnets 115, respectively. Hereinafter, the plurality of first through holes 121 are referred to as “first through holes 121” and the plurality of second through holes 122 as “second through holes 122”.

The first through holes 121 are located at an upper side of the magnetic shield 120, and the second through holes 122 are located at a lower side of the magnetic shield 120. That is, the first through holes 121 are positioned at regular intervals on the outer circumferential surface of the first magnetic shield 120a, and the second through holes 122 at regular intervals on the outer circumferential surface of the second magnetic shield 120b. Are respectively located.

Here, the first through holes 121 and the second through holes 122 are provided to have the same number as the number of N pole magnets 114 or S pole magnets 115 having the same number as described above. do. If the N pole magnet 114 is provided with eight, the first through-hole 121 is also made of eight numbers.

In addition, the second through holes 122 are positioned to alternate with the first through holes 121. That is, the second through the reference between the first one of the first through hole 121, which is a reference between the first through hole 121 and the first through hole 121 provided at a position adjacent thereto The hole 122 is formed.

In addition, the first through holes 121 and the second through holes 122 all have a shape having the same hole area. In the accompanying drawings, all of the first through holes 121 and the second through holes 122 are illustrated in a rectangular shape.

However, the first through holes 121 and the second through holes 122 may be formed in shapes such as "○", "□", "△", "▽", and "◇". And, as well as the above shapes, it may be made of a variety of shapes such as ellipses, holes, trapezoids.

However, the above shapes should be provided in a shape that is symmetrical in the left and right directions from the center of each hole (121, 122) region. In addition, it is preferable that all two or more of the shapes of the holes 121 and 122 are formed as the same, but the holes 121 and 122 having the same shape are all formed.

Here, the magnetic shield 120 is provided to have the same height as the height of the N pole magnet 114 and the S pole magnet 115, and the magnetic detection unit 130 to be described later.

That is, the top heights of the N pole magnets 114 and the S pole magnets 115 and the top height of the magnetic detection unit 130 are the same as the top heights of the first through holes 121 formed in the magnetic shield 120. do. The lower heights of the N pole magnets 114 and the S pole magnets 115 and the lower heights of the magnetic detection unit 130 are the same as the lower heights of the second through holes 122 formed in the magnetic shield 120. do.

However, this has described the most preferred embodiment, the top height of the N · S pole magnet 115 and the magnetic detector 130 is located differently from the top height of the first through hole 121, the N · S The bottom height of the pole magnet 115 and the magnetic detection unit 130 may be located differently from the bottom height of the second through hole 122.

As described above, the magnetic shield 120 having the above configuration has a connection member 150 coupled to a lower side thereof, and the connection member 150 has a central portion protruding downward and the output shaft 20 is inserted therein. Combined into a state. The coupling of the connection member 150 and the output shaft 20 can be coupled using a plurality of fastening members (not shown).

In addition, the output shaft 20 is provided with an insertion portion 21 at an upper end thereof, and is inserted into the connection member 150, and a connection groove 22 into which the lower end of the torsion bar 30 is inserted in the center of the insertion portion 21. ) Is formed. In addition, the torsion bar 30 is coupled to the output shaft 20 by pins 40b formed at the outer circumferential surface of the output shaft 20 with coupling holes 23 passing through the connection grooves 22.

On the other hand, the magnetic detector 130 is provided to be spaced apart from the outer peripheral surface of the magnetic shield 120, and serves to detect the magnetic force passing through the plurality of first through holes 121 and the second through holes 122. do.

The magnetic detection unit 130 is provided with a first magnetic detection member 131a and a second magnetic detection member 131b formed in the shape of a ring having a ferromagnetic material. The first magnetic detection member 131a includes a first collection. The magnetic ring 132a is connected, and the second magnetic collecting ring 132b is connected to the second magnetic detection member 131b.

The first magnetic detection member 131a and the second magnetic detection member 131b are positioned to be spaced apart from each other, and the top height of the first magnetic detection member 131a and the bottom height of the second magnetic detection member 131b are It may be provided to be the same as the height of the above-described N pole magnet 114 and S pole magnet 115, or to have a height smaller than this height.

In the latter case, that is, provided with a height lower than the height of the N-pole magnet 114 and the S-pole magnet 115, the upper end of the first magnetic detection member 131a defines the upper height region of the first through hole 121. It should not be removed, the lower end of the second magnetic detection member 131b is provided so as not to leave the lower height area of the second through hole 122.

Therefore, the magnetic force passing through the first through holes 121 is detected by the first magnetic detection member 131a, and the magnetic force passing through the second through holes 122 is detected by the second magnetic detection member 131b. Done.

The first collector ring 132a is coupled to the outer circumferential surface of the first magnetic detection member 131a, and the second collector ring 132b is coupled to the outer circumferential surface of the second magnetic detection member 131b. The first collector ring 132a and the second collector ring 132b are for maximizing the magnetic force induced from the magnetic force generating unit 110 around the magnetic detection sensor unit 140.

In addition, the outer circumferential surface of the first collector ring 132a is provided with a first protrusion member 132a 'protruding outward, and the outer circumferential surface of the second collector ring 132b is the same as the first protrusion member 132a'. The second protrusion member 132b 'positioned on the protrusion is provided to protrude in an outward direction.

The first protruding member 132a 'and the second protruding member 132b' may be provided in plural numbers so as to be positioned on the same vertical plane.

On the other hand, the magnetic detection sensor unit 140 is located on the outer circumferential surface of the magnetic detection unit 130 serves to detect the relative torsional change according to the area change of the magnetic force generating unit 110 and the magnetic shield 120. In the accompanying drawings, the magnetic detection sensor unit 140 is illustrated as one. However, the magnetic detection sensor unit 140 depends on the number of the first protrusion member 132a 'and the second protrusion member 132b' provided in the first collector ring 132a and the second collector ring 132b. .

That is, since the magnetic detection sensor unit 140 is provided between the first protrusion member 132a 'and the second protrusion member 132b', the magnetic detection sensor unit according to the number of the first and second protrusion members. The number of 140 will also vary.

In addition, since the magnetic detection sensor unit 140 for detecting magnetic force is a sensor widely used in the mechanical industry, detailed description thereof will be omitted.

The operation of the non-contact torque sensor 100 for a steering apparatus of the present invention made as described above will be described.

5 is a diagram illustrating a two-dimensional plan view of the torque sensor 100 having a circular structure in order to explain the operation and detection principle of the non-contact torque sensor 100 for a steering apparatus according to the present invention. 6A is an exploded view of the state of FIG. 5 in an overlapping state, FIG. 6B is a cross-sectional view of the B-B part shown in FIG. 6A, and FIG. 6C is a cross-sectional view of the C-C part shown in FIG. 6A.

As shown in the drawings, the height of the magnetic shield 120 is located in the height region of the magnetic force generating unit 110, the first magnetic detection member 131a provided in the magnetic detection unit 130 is the first through hole Located in the height region of the field 121. In addition, the second magnetic detection member 131b provided in the magnetic detection unit 130 is positioned in the height region of the second through holes 122. In addition, the horizontal length of the first through holes 121 is located in the horizontal length area of the N pole magnet 114, the horizontal length of the second through holes 122 is the horizontal length area of the S pole magnet 115 Is located within.

Here, the horizontal length of the first through holes 121 may be located in the horizontal length area of the S-pole magnet 115. In this case, the horizontal length of the second through holes 122 is located in the horizontal length area of the N pole magnet 114.

7A is an exploded view showing a state where the twist of the input shaft 10 and the output shaft 20 is not generated, that is, the neutral state of the torque sensor 100. As shown in the figure, the handle shaft and the wheel shaft is rotated at the same angle, or the state in which the torsion of the input shaft 10 and the output shaft 20 in the stationary state is "0".

More specifically, when the driver manipulates the steering wheel, the input shaft 10 connected thereto rotates, and the output shaft 20 connected to the torsion bar 30 rotates to change the wheel in the traveling direction.

At this time, when the output shaft 20 is rotated in the same manner as the input shaft 10 and the torsion angle is "0", the boundary between the N pole magnet 114 and the S pole magnet 115 is formed in the first through hole 121 and the first pole. It will be located in the center of the two through-holes 122.

That is, since the N pole magnet 114 and the S pole magnet 115 provided in the magnetic force generating unit 110 rotate while being exposed to the same area of the first through hole 121 and the second through hole 122, respectively. In the magnetic detection unit 130, the magnetic force of the two polarities is canceled out so that there is no polarity.

More specifically, each of the first through holes 121 and the second through holes 122 has 50% of the surface where the magnetic force of the N pole is exposed, and 50 is the surface of the magnetic pole of the S pole that is exposed to each of the holes. %to be. Therefore, the polarity detected by the magnetic detection unit 130 through one hole is in a state of "0".

7B is an exploded view showing a case in which the output shaft 20 is distorted in the left direction with respect to the input shaft 10, and FIG. 7C is a maximum twist in the left direction with respect to the input shaft 10 in the output shaft 20. It is a developed view showing the case where this occurred.

As shown in the figure, the left torsion is a state where the torsion occurs between the input shaft 10 and the output shaft 20 by friction between the wheel and the road surface when the driver turns the steering wheel to the left.

That is, a torsion is generated in the torsion bar 30 connecting the input shaft 10 and the output shaft 20. When the torsion is gradually increased, the first through holes 121 are S-pole magnets for each hole. The exposed surface of 115 increases, and the N-pole magnet 114 gradually decreases as the exposed surface of the S-pole magnet 115 increases.

The second through holes 122 have larger exposed surfaces of the N pole magnets 114 for each hole, and the S pole magnets 115 gradually increase as the exposed surfaces of the N pole magnets 114 increase. To decrease.

Accordingly, a difference in magnetic force induced by the N pole magnet 114 and the S pole magnet 115 is generated in the first magnetic detection member 131a provided in the magnetic detection unit 130 to have the polarity of the N pole. The second magnetic detection member 131b has a polarity of the S pole which is a magnetic force of an amount opposite to the magnetic force induced by the first magnetic detection member 131a.

That is, as shown in FIG. 7C, when the torsion in the left direction is maximum, the first magnetic detection member 131a has the polarity of the N pole, and the second magnetic detection member 131b has the polarity of the S pole. Will have

Therefore, the polarity of the N pole induced by the first magnetic detection member 131a induces the N pole from the upper end of the magnetic detection sensor unit 140 by the first magnetic ring 132a, and the second magnetic detection member 131b. The polarity of the S pole induced in the) is induced by the second collector ring 132b to induce the S pole at the lower end of the magnetic detection sensor unit 140. Then, a magnetic field is formed around the magnetic detection sensor unit 140 so that the magnetic flux density at this time is detected by the magnetic detection sensor unit 140.

As described above, the process in which the torsion occurs in the input shaft 10 and the output shaft 20 is linearly increased from the beginning of the torsion until the maximum torsion occurs. This serves to increase or decrease the area change of the magnetic detection unit 130 and the magnetic force generating unit 110 by the first through holes 121 and the second through holes 122 provided in the magnetic shield 120. Therefore, the amount of change in the magnetic flux density formed around the magnetic detection sensor unit 140 increases and decreases linearly.

In the above, the description has been made based on the time when the leftward twist occurs between the input shaft 10 and the output shaft 20. However, since the polarity is changed depending on the position at which the N-pole magnet 114 and the S-pole magnet 115 are inserted, the leftward twist described above may be a condition of the rightward twist.

In addition, since the above-described leftward twist described above is based on a specific direction using the accompanying drawings as an example, the rightward twist may be generated.

On the other hand, when torsion in the right direction opposite to the left direction in the above-described direction occurs, since the polarity of the magnetic field formed around the magnetic detection sensor unit 140 is reversed, the output value also changes the phase of 180 degrees. It will be given a value that will be omitted and this detailed description will be omitted and refer to the accompanying Figures 8a and 8b.

First, FIG. 8A is an exploded view showing a case in which the output shaft 20 is twisted in a right direction with respect to the input shaft 10, and FIG. 8B is a maximum in the right direction with respect to the input shaft 10. It is a developed view showing the case where torsion occurs.

Meanwhile, as shown in FIG. 9, the magnetic force generating unit 110 ′ provided in the non-contact torque sensor for the steering apparatus according to the present invention described above includes an N pole magnet 114 ′ and an S pole magnet 115 ′. The magnets are staggered along the outer circumferential surface of the upper part of the magnet, and another S pole magnet 115 ″ is disposed below the N magnet 114 ′, and further below the S pole magnet 115 ′. Another N pole magnet 114 ″ is disposed.

In this case, one through hole 121 'is formed at the boundary between the magnets 114', 114 ", 115 ', and 115 " in the magnetic shield 120', and each boundary has the same shape. The through hole 121 'is formed.

Therefore, when torsion occurs in the left direction, for each through hole 121 ', the S-pole magnet 115' located at the upper right side as shown in the drawing, and the N-pole magnet 114 'located at the lower right side The exposed surface of ') becomes gradually larger.

On the contrary, for each through hole 121 ', the exposed surface of the N pole magnet 114 " located at the top of the left side and the S pole magnet 115 " located at the bottom of the left side as shown in the drawing are gradually formed. It becomes small.

Accordingly, a difference in magnetic force induced through the through holes 121 ′ occurs between the first magnetic detection member 131 a and the second magnetic detection member 131 b provided in the magnetic detection unit 130. 140).

1 is a perspective perspective view of a non-contact torque sensor for a steering apparatus according to the present invention;

2 is an exploded perspective view of a non-contact torque sensor for a steering apparatus according to the present invention;

3 is a cross-sectional view of the A-A portion shown in Figure 1 of the non-contact torque sensor for a steering apparatus of the present invention;

4 is a plan view of a non-contact torque sensor for a steering apparatus of the present invention;

5 is a development view showing a non-contact torque sensor for a steering apparatus of the present invention in a two-dimensional plane,

6A is an exploded view showing the state of FIG. 5 in an overlapping state;

6B is a cross-sectional view of the B-B portion shown in FIG. 6A;

6C is a cross-sectional view of the C-C portion shown in FIG. 6A;

7A is an exploded view showing a neutral state of a non-contact torque sensor for a steering apparatus of the present invention;

Figure 7b is an exploded view showing a state in which the output shaft connected to the non-contact torque sensor for the steering apparatus of the present invention is torsion in the left direction,

7C is an exploded view showing a state in which an output shaft connected to a non-contact torque sensor for a steering apparatus of the present invention has a maximum twist in a left direction;

8A is an exploded view illustrating a state in which an output shaft connected to a non-contact torque sensor for a steering apparatus of the present invention is twisted in a right direction;

8B is an exploded view showing a state in which an output shaft connected to a non-contact torque sensor for a steering apparatus of the present invention has a maximum twist in a right direction;

9 is an exploded view of another embodiment showing a neutral state of the magnetic force generating portion and the magnetic shielding portion provided in the non-contact torque sensor for the steering apparatus of the present invention.

Explanation of symbols on the main parts of the drawings

100: torque sensor 110,110 ': magnetic force generating unit

111: through hole 112: coupling portion

113: Magnet fixing part 114,114 ', 114' ': N pole magnet

115,115 ', 115' ': S pole magnet 120,120': Magnetic shield

121: first through hole 122: second through hole

130: magnetic detection unit 131a: first magnetic detection member

131b: second magnetic detection member 132a: first magnetic ring

132a ': first protruding member 132b: second collecting ring

132b ': second protruding member 140: magnetic detection sensor

Claims (16)

In the non-contact torque sensor for steering apparatus is installed between the input shaft connected to the steering wheel of the vehicle and the output shaft connected to the wheel of the vehicle to detect the torsion generated by the rotation operation of the steering wheel, A magnetic force generating unit coupled to the input shaft and having a plurality of N pole magnets and S pole magnets alternately arranged along an outer circumferential surface of the center to have the same radius; A magnetic shield having a cylindrical shape and connected to the output shaft and having a plurality of holes formed in the plurality of N-pole and S-pole magnets, respectively; A magnetic detection unit provided to be spaced apart from an outer circumferential surface of the magnetic shield and detecting a magnetic force passing through the plurality of holes; And And a magnetic detection sensor unit positioned on an outer circumferential surface of the magnetic detection unit to sense a relative torsional change in the magnetic force generating unit and the magnetic shield. The method of claim 1, The magnetic force generation unit, A coupling part fixed to a lower end of the input shaft; And Including the lower portion of the coupling portion is a cylindrical magnet fixing; including, The non-contact torque sensor for steering apparatus, characterized in that the plurality of the N pole magnet and the S pole magnet is coupled to the outer peripheral surface of the magnet fixing part. The method of claim 1, The magnetic shield, A first magnetic shield including a plurality of first holes formed in the upper outer circumferential surface at regular intervals; And A non-contact torque sensor for a steering apparatus, comprising: a second magnetic shield formed at a predetermined interval on a lower outer circumferential surface of the first magnetic shield and including a second through hole arranged to be alternate with the first through hole; . The method of claim 3, wherein And the output shaft is rotated in the same manner as the input shaft so that the torsion angle is "0", wherein the boundary between the N pole magnet and the S magnet is located at the vertical center of the hole. The method of claim 3, wherein When the output shaft has a maximum twist in a left or right direction with respect to the input shaft, a magnet of any one of the S-N pole magnets is exposed through a plurality of first through holes, and a plurality of second through holes are exposed. Non-contact torque sensor for steering apparatus, characterized in that the other one through the magnet is exposed. The method according to any one of claims 3 to 5, A plurality of the first through hole and the second through hole, Non-contact torque sensor for steering apparatus, characterized in that each of the shape having a region of the same hole. The method of claim 6, An upper end height of the N-S pole magnet and the magnetic detection unit is equal to an upper end height of the first through hole, And the lower end heights of the N-S pole magnets and the magnetic detection unit are located at the same height as the lower end heights of the second through holes. The method of claim 6, The upper end height of the N-S pole magnet and the magnetic detection unit are located differently from the upper end height of the first through hole, And the lower heights of the N-S pole magnets and the magnetic detection portion are different from the lower heights of the second through holes. The method of claim 3, wherein The magnetic detection unit, A first magnetic detecting member detecting a magnetic force passing through the first through hole; And And a second magnetic detection member positioned to be spaced apart from the lower side of the first magnetic detection member, the second magnetic detection member detecting a magnetic force passing through the second through hole. The method of claim 9, The magnetic detection unit, A first confining ring provided on an outer circumferential surface of the first magnetic detecting member to maximize the magnetic force induced from the magnetic generating unit; And And a second dust collector ring provided on an outer circumferential surface of the second magnetic detection member. The method of claim 10, Non-contact torque sensor for a steering apparatus, characterized in that at least one of the magnetic detection sensor unit is connected to the first and the second collector ring. The method of claim 11, The magnetic detection unit, A first protruding member protruding outward from an outer circumferential surface of the first dust collecting ring; And And a second protrusion member protruding outward from an outer circumferential surface of the second dust collecting ring and positioned on the same vertical position as the first protrusion member. And said magnetic detection sensor portion is located between said first projection member and said second projection member. The method of claim 12, The first protrusion member is provided in plural on the outer circumferential surface of the first collector ring, the second protrusion member is provided in plural on the outer circumferential surface of the second collector ring, the magnetic between the plurality of first second protrusion member Non-contact torque sensor for steering apparatus, characterized in that the detection sensor unit is located respectively. The method of claim 3, wherein The magnetic shield, The first magnetic shield part and the second magnetic shield part is a non-contact torque sensor for a steering apparatus, characterized in that the one-piece manufacturing. The method of claim 1, The magnetic force generating unit, The N-pole and S-pole magnets are alternately arranged along an upper outer circumferential surface, and another S-pole magnet is disposed below the N-pole magnet, and another N-pole is disposed below the S-pole magnet disposed on the upper outer circumferential surface. Non-contact torque sensor for steering apparatus, characterized in that the magnet is disposed. The method of claim 15, The magnetic shield, The non-contact torque sensor for a steering system, characterized in that the hole is disposed at the boundary between the N pole magnet and the S pole magnet disposed on the upper outer circumferential surface, and the N pole magnet and the S magnet disposed on the lower outer circumferential surface.

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