KR101949432B1

KR101949432B1 - Torque sensor unit

Info

Publication number: KR101949432B1
Application number: KR1020140119318A
Authority: KR
Inventors: 전창남
Original assignee: 엘에스오토모티브테크놀로지스 주식회사
Priority date: 2014-09-05
Filing date: 2014-09-05
Publication date: 2019-02-19
Also published as: KR20160029987A

Abstract

A torque sensor of the present invention is disposed between an input shaft and an output shaft and senses a torque between an input shaft and an output shaft through a relative rotational displacement between an input shaft and an output shaft. The torque sensor device includes an input shaft and an output shaft, A housing capable of rotating relative to an input shaft and an output shaft: a magnet unit connected to one end of an input shaft and an output shaft, and including a magnet ring accommodated in the housing so as to be rotatable within the housing; A collector unit connected to one end of the other one of the input shaft and the output shaft and rotatably arranged in the housing to form a magnetic circuit with the magnet unit; And a sensing unit disposed on an outer circumferential side of the collector unit and sensing a magnetic field focused through the collector unit, wherein the collector unit includes: an upper collector disposed on one side of the input shaft and the output shaft, A lower collector disposed to be spaced apart from the upper collector, a picking collector spaced apart from the outer periphery of the upper collector and the lower collector, fixedly disposed in the housing, and each having one end disposed with the torque sensor interposed therebetween The upper collector includes: a ring-shaped upper collector ring disposed on one end of the other of the input shaft and the output shaft on a radially outer circumference; and a plurality of upper collector teeth extending from the end of the upper collector ring , The lower collector includes: an input shaft and a radially outer periphery of the output shaft And a plurality of lower collector teeth spaced apart from ends of the lower collector ring, wherein one of the upper collector teeth and the lower collector teeth is disposed in the axial direction of the input shaft and the output shaft And the other of the upper collector teeth and the lower collector teeth is formed in a radial direction of the input shaft and the output shaft.

Description

TORQUE SENSOR UNIT

The present invention relates to a torque sensor, and more particularly, to a torque sensor for sensing an applied torque to a shaft having an input shaft and an output shaft.

Generally, as the steering steering wheel is rotated when the vehicle is running or stopped, the wheel in contact with the road surface also rotates. That is, when the steering wheel is rotated leftward or rightward, the wheel rotates in the same direction. Since the wheel is in contact with the road surface, the steering ratio between the steering steering wheel and the wheel is different from each other due to the friction between the wheel and the road surface, so that the driver needs a large force to operate the steering steering wheel. .

A power steering system (PS) is provided as a device for assisting the steering force, and an EPS system using an electric motor among power steering systems is expanding its application range in passenger vehicles used in real life.

In order to assist the power assist in such a power steering system, a torque sensor for measuring the rotational angle deviation between the input shaft side connected to the steering steering wheel and the output shaft side interlocked with the wheel side Respectively.

The torque sensor is largely classified into a contact type and a non-contact type. Recently, a non-contact type torque sensor is adopted as a contact type due to a problem of reduction in noise and durability. The non-contact type torque sensor is classified into a magnetoresistance detection method, a magnetostriction detection method, a capacitance detection method, and an optical detection method.

On the other hand, in the conventional torque sensor of the magnetic resistance detection system provided in the electric power steering apparatus, the steering steering wheel to be operated by the driver is coupled to the upper end of the input shaft, and the lower end of the input shaft is connected to a torsion bar bar 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 on the outside thereof. In addition, the above-mentioned torque sensor and power means are installed inside the housing. Here, the input shaft is provided with a permanent magnet having a polarity crossing at a constant interval. A detection ring of the gear structure corresponding to the number of poles of the permanent magnet is provided on the output shaft as a ferromagnetic substance which can be magnetically induced by the permanent magnet provided on the input shaft. The detection ring is connected to a sensor for detecting magnetism. At this time, a change in the area corresponding to each other is caused by the relative torsion between the permanent magnet installed on the input shaft and the detection ring of the gear structure provided on the output shaft. Therefore, a change in the magnetic force is generated in the detection ring, and the sensor detects the change in the magnetic force, so that the output shaft senses the angle at which the twist occurs with respect to the input shaft.

However, the non-contact type torque sensor according to the related art has a problem that the malfunction is increased, the manufacturing cost is increased, and the durability problem due to the excessive component is exposed because the components are excessive and the assembly is complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a torque sensor which can be manufactured with a simple structure, increases sensitivity, increases sensing reliability, and reduces manufacturing cost.

In order to achieve the above object, a torque sensor according to the present invention is disposed between an input shaft and an output shaft and detects a torque between an input shaft and an output shaft through a relative rotational displacement between an input shaft and an output shaft. And a magnet ring which is connected to one end of the input shaft and the output shaft and is accommodated in the housing so as to be rotatable inside the housing, Unit; A collector unit connected to one end of the other one of the input shaft and the output shaft and rotatably arranged in the housing to form a magnetic circuit with the magnet unit; And a sensing unit disposed on an outer circumferential side of the collector unit and sensing a magnetic field focused through the collector unit, wherein the collector unit includes: an upper collector disposed on one side of the input shaft and the output shaft, A lower collector disposed to be spaced apart from the upper collector, a picking collector spaced apart from the outer periphery of the upper collector and the lower collector, fixedly disposed in the housing, and each having one end disposed with the torque sensor interposed therebetween And the upper collector includes: a ring-shaped upper collector ring arranged on a radially outer periphery at one end of the other of the input shaft and the output shaft; and a plurality of upper collector teeth extending from the end of the upper collector ring , The lower collector includes: an input shaft and an output shaft And a plurality of lower collector teeth spaced apart from ends of the lower collector ring, wherein one of the upper collector tooth and the lower collector tooth is connected to the input shaft and the lower collector collector ring, And the other one of the upper collector tooth and the lower collector tooth is formed in a radial direction of the input shaft and the output shaft.

In the torque sensor device, the upper collector teeth may be formed along the longitudinal direction of the output shaft on the output shaft side.

In the torque sensor device, two magnet rings are provided, and the lengths of the input shaft and the output shaft of the magnet ring in the axial direction may be different from each other.

In the torque sensor device, a magnet ring having a large length in the axial direction of the input shaft and the output shaft of the magnet ring of the magnet ring is disposed on the upper collector tooth side, and the length in the longitudinal direction of the output shaft of the upper collector tooth, The length in the axial direction of the input shaft and the output shaft of the magnet ring in the ring may be larger than the axial length of the magnet ring having a larger length.

In the torque sensor device, the magnet ring having a small length in the axial direction of the input shaft and the output shaft of the magnet ring is disposed on the lower collector side, and the output shaft radial length of the lower collector tooth is smaller than the length The length of the radial echoes of the input shaft and the output shaft of the magnet ring in the ring may be larger than the radial length of the magnet ring having a small length.

In the torque sensor device, the magnet ring may include: an upper magnet ring disposed corresponding to the upper collector; and a lower magnet ring arranged to face the lower collector, wherein the upper magnet ring and the lower magnet ring The aspect ratio ARu of the upper magnet ring may be less than the aspect ratio AB1 of the lower magnet ring with respect to the cross section formed in the longitudinal direction of the input shaft and the output shaft.

The magnetic force lines of the upper magnet ring are formed in a circumferential direction on a circumferential surface parallel to the longitudinal direction of the input shaft and the output shaft of the upper magnet ring and the magnetic force lines of the lower magnet ring are formed on the input shaft of the lower magnet ring, And a longitudinal direction of the input shaft and the output shaft on a circumferential surface perpendicular to the output shaft.

The torque sensor device according to the present invention having the above-described configuration has the following effects.

The torque sensor device of the present invention has a structure in which the collector of the collector unit is arranged vertically and minimizes the amount of leakage of magnetic flux through each collector and increases the amount of magnetic flux transmitted to the torque sensor, .

1 is a schematic exploded perspective view of a torque sensor device according to an embodiment of the present invention.
2 is another partial exploded perspective view of a torque sensor device according to an embodiment of the present invention.
3 is a partial cross-sectional view of the collector unit.

Hereinafter, the configuration and operation of the torque sensor device 10 of the present invention will be described with reference to the accompanying drawings.

The torque sensor device 10 of the present invention includes a housing 100, a magnet unit 200, a collector unit 300 and a sensing unit 400. The torque sensor device 10 of the present invention includes an input shaft 2, And the output shaft 3 to sense the torque between the input shaft 2 and the output shaft 3 through the relative rotational displacement of the input shaft 2 and the output shaft 3.

The housing 100 accommodates the end portions of the input shaft 2 and the output shaft 3 and is positionally fixed and movable relative to the input shaft 2 and the output shaft 3.

The housing 100 includes a housing cover 110 and a housing base 120. The housing cover 110 is fastened to the housing base 120 to form an interior space for receiving other components.

The housing cover 110 is disposed on the input shaft side and the housing base 120 is disposed on the output shaft 3 side facing the housing cover 110. A housing cover mounting portion (not shown) is provided on the outer periphery of the housing cover 110, and a housing base mounting portion (not shown) is disposed on the outer periphery of the housing base 120 to form a structure in which they are engaged with each other.

The housing cover 110 and the housing base 120 each have a housing cover through-hole 113 and a housing base through-hole (not shown) respectively at the center thereof to receive the input shaft 2 and the output shaft 3, So that the torsion bar 5, which directly connects the output shaft 3, can be arranged to be inserted therethrough.

The magnet unit 200 includes a magnet ring 220 connected to one end of the input shaft 2 and the output shaft 3 and rotatably received in the housing 100.

That is, the magnet unit 200 is connected to either the input shaft or the output shaft, that is, to the input shaft 2 side in the present embodiment and rotates together with the input shaft 2, so that the magnet unit 200 is accommodated in the housing 100 so as to be rotatable relative to the housing 100 .

The magnet unit 200 may have various configurations. However, in this embodiment, the magnet unit 200 includes the magnet ring 220.

Although not shown in this embodiment, the magnet unit may further include a magnet holder so that the magnet holder supports the magnet ring 220 on the input shaft side. The magnet ring 220 of the present invention has a structure in which different polarities are arranged in the circumferential direction of the input shaft 2 and the output shaft 3, that is, a structure in which N, S or S and N poles are arranged or magnetized in the circumferential direction do.

In this embodiment, a plurality of magnet rings are provided. More specifically, two magnet rings are provided, and the magnet ring 220 includes an upper magnet ring 2210 and a lower magnet ring 2220. The upper magnet ring 2210 is disposed in correspondence with the upper collector 310 of the collector unit described below and the lower magnet ring 2220 is disposed to face the lower collector 320. The upper magnet ring 2210 includes the upper magnet ring 2210, The aspect ratio ARu of the upper magnet ring 2210 with respect to the cross section formed in the longitudinal direction of the input shaft 2 and the output shaft 3 is smaller than the aspect ratio ARu of the lower magnet ring 2210, (ARl) of the second lens 2220. [

3, the aspect ratio ARu = d1 / t1 of the upper magnet ring 2210 has a smaller value than the aspect ratio ARl = d2 / t2 of the lower magnet ring 2220. In other words,

3, the magnetic force lines of the upper magnet 2210 are formed on the circumferential surface of the upper magnet 2210, more specifically, on the circumferential surface of the upper magnet 2210. More specifically, the magnetic force lines of the upper magnet 2210 and the lower magnet 2210, Magnetic lines of force are formed on circumferential surfaces of the input shaft 2 and the output shaft 3 in the circumferential direction on the main surface in the circumferential direction and adjacent to the circumferentially adjacent ones of the polarities and the lines of magnetic force of the lower magnets 2220 are adjacent to each other in the circumferential direction And are formed in the longitudinal direction of the input shaft 2 and the output shaft 3 on the circumferential surface perpendicular to the input shaft 2 and the output shaft 3,

That is, the magnetic field is mainly formed between the adjacent polarities on the outer side and the inner side on the upper magnet 2210, and the magnetic field is mainly formed on the surface of the lower magnet 2220 toward the input shaft and the output shaft.

At least a part of the collector unit 300 is fixedly mounted on the other of the input shaft and the output shaft side, that is, on the output shaft 3 side in this embodiment, and is accommodated so as to be rotatable relative to the housing 100.

At least a part of the collector unit 300 is disposed outside the magnet ring 220 in the radial direction of the input shaft 3 and the output shaft 4 so that the magnetic field generated by the magnet ring 220 of the magnet unit 200 And transmits the signal to the sensor unit 400 which forms a magnetic path or focuses the magnetic field, thereby realizing a more accurate sensing function.

The sensing unit 400 is implemented as a torque sensor that is disposed on the outer circumferential side of the collector unit 300 and senses a magnetic field to be focused through the collector unit 300. The sensing unit may further include a separate sensor as the case may be.

In this embodiment, the sensing unit is implemented by one torque sensor, but it may include two torque sensors depending on the case, thereby improving the sensitivity accuracy and implementing a fail-safe function by outputting other signals in any one of failures .

The collector unit 300 of the present invention includes an upper collector 310, a lower collector 320, and a picking collector 330.

The upper collector 310 is disposed toward one of the input shaft and the output shaft and the lower collector 320 is disposed apart from the upper collector 310. The upper collector 310 and the lower collector 320, which are positioned and fixed to the housing 100 and are disposed with a sensing unit 400 having one end implemented as a torque sensor.

The upper collector 310 includes an upper collector ring 311 and an upper collector tooth 313.

The upper collector ring 311 has a predetermined ring shape formed on the other side of the input shaft 2 and the output shaft, that is, on the radial outer periphery of the output shaft 3 in this embodiment. A plurality of upper collector teeth 313 are provided and are formed in the longitudinal direction of the output shaft 2 from the end of the upper collector ring 311 and spaced apart in the circumferential direction.

Further, the lower collector 320 is connected to the output shaft side and rotates together with the output shaft.

A lower collector sleeve (not shown) and a lower collector holder (not shown) may further be provided between the lower collector 320 and the output shaft 3, which may have the same configuration in the above-described upper collector. The lower collector sleeve is connected to the output shaft 3 at one end. The connection between the lower collector sleeve and the output shaft 3 can be variously combined to prevent relative rotation between welding, plastic snap fit, and caulking. Do.

Further, the lower collector sleeve may be a steel structure or a synthetic resin structure, and various modifications are possible according to design specifications.

Further, a lower collector holder is connected to the outer periphery of the lower collector sleeve. The lower collector holder is a component for connecting the lower collector sleeve to the lower collector and ultimately implements a coupling function to prevent relative rotation between the input shaft and the lower collector 320.

The lower collector 320 includes a lower collector ring 321 and a lower collector column 323.

The lower collector ring 321 has a predetermined ring shape formed and arranged in the rotating direction of the output shaft 3. A plurality of lower collector teeth 323 are formed and spaced along the circumference from the end of the lower collector ring 321 in the inner radial direction on a plane perpendicular to the output shaft 3.

That is, the upper collector teeth and the lower collector teeth form a vertical arrangement relationship.

On the other hand, in this embodiment, a plurality of magnet rings are provided. More specifically, two magnet rings are provided, and the magnet ring 220 includes an upper magnet ring 2210 and a lower magnet ring 2220. The lengths of the upper magnet ring 2210 and the lower magnet ring 2220 in the longitudinal direction of the input shaft and the output shaft are different from each other. That is, the length t1 of the input shaft and the output shaft of the upper magnet ring 2210 in the longitudinal direction has a larger value than the length t2 of the input shaft and output shaft of the lower magnet ring 2220 in the longitudinal direction.

The length 12 in the length direction perpendicular to the input shaft and the output shaft of the lower collector tooth 323 is greater than the length d2 in the direction perpendicular to the input shaft and the output shaft of the lower magnet ring 2210, So as to facilitate collection of the magnetic field from the lower magnet ring 2210.

The picking collector 330 is positioned and fixed to the housing 100 by being spaced apart from the outer periphery of the upper collector 310 and the lower collector 320 and each end of the picking collector 330 is disposed with the torque sensor 400 interposed therebetween.

The picking collector 330 includes an upper picking collector 340 and a lower picking collector 350.

The upper picking collector 340 includes an upper picking plate 341 and an upper picking terminal 343.

The upper fixing plate 341 is disposed on the outer peripheral side of the upper collector 310 and the upper fixing terminal 343 is disposed on the outer periphery of the upper fixing plate 341 toward the torque sensor 400. The upper fixing plate 341 is arranged such that the upper fixing plate 341 overlaps the upper collecting ring 311 of the upper collector 310 when viewed on a plane perpendicular to the input shaft and the output shaft, The gap between the inner side and the outer side of the upper collector ring 311 is larger than the gap between the inner diameter and the outer diameter of the uppercylar lettering 311 to minimize the magnetic flux leakage from the upper collector ring.

The upper picking terminal 343 is provided with a predetermined bending shape so that the end portion thereof is brought close to the torque sensor 400 to reduce the air gap, thereby increasing the transfer of the magnetic flux to the torque sensor 400 side, .

The upper fixing plate 341 and the upper fixing terminal 343 are integrally formed. One end of the upper picking plate 341 is arranged close to the upper collector 310 and an end of the upper picking terminal 343 is arranged close to the torque sensor 400 on the opposite side of the upper collector 310.

The lower picking collector 350 includes a lower picking plate 351 and a lower picking terminal 353. The overall structure is the same as that of the above-described upper picking collector 340, but may take a somewhat different configuration depending on the case.

The lower fixing plate 351 is disposed on the outer periphery of the lower collector 310,

The lowering plate 351 is arranged so that the lowering plate 351 overlaps the lower collector ring 321 of the lower collector 310 when viewed on a plane perpendicular to the input shaft and the output shaft, The gap between the inner side and the outer side of the lower collector ring 321 is larger than the gap between the inner diameter and the outer diameter of the lower collector ring 321 to minimize the magnetic flux leaking from the lower collector ring.

The lowering terminal 353 is disposed toward the torque sensor 400 on the outer periphery of the lower fixing plate 351. The lowering terminal 353 has a predetermined bending shape so that the end portion thereof is brought close to the torque sensor 400 to reduce the air gap, thereby increasing the magnetic flux attracted to the torque sensor 400 side for more accurate detection .

The lower fixing plate 351 and the lower fixing terminal 353 are integrally formed. One end of the lower picking plate 351 is arranged close to the lower collector 310 and an end of the lower picking terminal 353 is arranged close to the torque sensor 400 on the opposite side of the lower collector 310.

As described above, according to the present invention, the torque applied to the shaft can be variously changed within a range of sensing through a non-contact type method.

100 ... housing 110 ... housing cover
120 ... housing base 200 ... magnet unit
300 ... collector unit 400 ... sensing unit

Claims

A torque sensor device disposed between an input shaft and an output shaft for detecting a torque between an input shaft and an output shaft through a relative rotational displacement between an input shaft and an output shaft, A magnet unit including a magnet ring which is connected to one end of an input shaft and an output shaft and is accommodated in the housing so as to be rotatable inside the housing; At least a part of which is connected to one end of the other of the input shaft and the output shaft, and which is rotatably disposed inside the housing to form a magnetic circuit with the magnet unit; And a sensing unit disposed on an outer circumferential side of the collector unit and sensing a magnetic field focused through the collector unit, wherein the collector unit includes: an upper collector disposed on one side of the input shaft and the output shaft, A lower collector disposed to be spaced apart from the upper collector, a picking collector spaced apart from the outer periphery of the upper collector and the lower collector, fixedly disposed in the housing, and each having one end disposed with the torque sensor interposed therebetween The upper collector includes: a ring-shaped upper collector ring disposed on one end of the other of the input shaft and the output shaft on a radially outer circumference; and a plurality of upper collector teeth extending from the end of the upper collector ring , The lower collector includes: an input shaft and an output shaft And a plurality of lower collector teeth spaced apart from ends of the lower collector ring, wherein one of the upper collector tooth and the lower collector tooth is connected to the input shaft and the lower collector collector ring, And the other of the upper collector teeth and the lower collector teeth is formed in the radial direction of the input shaft and the output shaft,
The upper collector tooth is formed along the longitudinal direction of the output shaft on the output shaft side,
Wherein two magnet rings are provided, the lengths of the input shaft and the output shaft of the magnet ring in the axial direction are different from each other,
A magnet ring having a large length in the axial direction of the input shaft and the output shaft of the magnet ring among the magnet rings is disposed on the upper collector tooth side,
The length of the upper collector teeth in the longitudinal direction of the output shaft is larger than the axial length of the magnet ring having a larger length in the axial direction of the input shaft and the output shaft of the magnet ring,
Wherein the magnet ring includes: an upper magnet ring arranged corresponding to the upper collector; and a lower magnet ring arranged to face the lower collector, wherein the upper magnet ring and the lower magnet ring are arranged in a circumferential direction with N pole and S The aspect ratio ARu of the upper magnet ring is less than the aspect ratio AB1 of the lower magnet ring with respect to the cross section formed in the longitudinal direction of the input shaft and the output shaft,
Wherein a magnetic line of force of the upper magnet ring is formed in a circumferential direction on a circumferential surface parallel to a longitudinal direction of an input shaft and an output shaft of the upper magnet ring and a magnetic force line of the lower magnet ring is formed on a circumferential surface perpendicular to an input shaft and an output shaft of the lower magnet ring Is formed in the longitudinal direction of the input shaft and the output shaft.

delete

The method according to claim 1,
The magnet ring having a small length in the axial direction of the input shaft and the output shaft of the magnet ring is disposed on the lower collector side,
Wherein an output shaft radial length of the lower collector tooth is larger than a radial length of a magnet ring having a smaller radial echo length of the input shaft and the output shaft of the magnet ring.

delete