KR101932820B1 - Torque detecting device - Google Patents

Abstract

The torque detection device 200 is adapted to be mounted on the torque transmission device 8. The torque transmission device 200 includes a rotatable input and an output shaft 81,82. The torque detection device 200 includes input and output gears 2 and 3 for respective sleeve connection on input and output shafts 81 and 82 and input and output gears 2 and 3 respectively connected to the input gear 2 and the ring gear 41 And a planetary gear unit 4 including a plurality of planetary gears 44. The planetary gear unit 4 includes a plurality of planetary gears 42, a carrier gear 43 that meshes with the output gear 3, The planetary gear 44 is rotatably engaged with the carrier gear 43 and is arranged between the sun gear 42 and the ring gear 41 and engaged with the ring gear 41 and the sun gear 42, 2 is rotated by a certain angle with respect to the output gear 3, the sun gear 42 is driven to rotate in the reverse direction by a larger angle.

Description

[0001] TORQUE DETECTING DEVICE [0002]

The present invention relates to a torque detection device, and more particularly, to a torque detection device capable of linearly amplifying the rotation angle of a torsion bar.

Referring to FIG. 1, a power assistance function is provided in a vehicle steering system so that the driver can more easily control the vehicle. In existing markets, an ordinary vehicle is typically provided with an electric power steering system 91 (abbreviated EPS system).

The main function of the torque detector 92, which is a key component of the EPS system, is to detect the steering torque applied by the driver when the steering wheel 93 is rotated. Such an object is achieved by mounting a torque detector 92 on a torsion shaft (not shown) to detect an angle change of the torsion bar to produce an output signal corresponding to the angle change.

Torque detection devices available on the market today usually operate under the Hall effect principle. 2, a conventional torque detection device is provided with a hole induction system and includes a rotor 95, a pair of stator 96, and a hole element 97. The rotor 95 has an outer ring fitted with a plurality of magnets having N-S poles fixed to the end of a torque transfer device (not shown) in which the torsion bars are arranged and arranged back and forth. Each of the stator 96 has a plurality of claws, is fixed to the other end of the torque transfer device, and is made of a material having a magnetic permeability. The Hall element 97 is fixed to the housing of a conventional torque detecting device to sense magnetic flux. When the input shaft rotates with respect to the output shaft, the rotor 95 moves relative to the stator 96, resulting in a change in magnetic flux. In this way, the Hall element 97 can sense a change in magnetic flux and can determine the torque value.

The Hall element 97 can be used to determine the torque value according to the relative angle created between the output shaft of the torque transfer device and the input shaft. However, since the rotation of the input shaft relative to the output shaft is relatively small, high precision is required for the structure of the hole element 97 and other related elements.

Chinese patent CN101825425B discloses another conventional torque detection device that senses the rotation angle of the shaft relative to other shafts. A conventional torque detection device includes two planetary gear units. Each planetary gear unit has a sun gear coupled to each one of the shafts and a detection gear coupled to the sun gear. Rotation of the shaft relative to the other shaft results in relative movement between the sun gears of the two planetary gear units. Since the number of teeth of the detection gears of the two planetary gear units is different, the detection gears of the two planetary gear units rotate at different rotation angles. As described above, the steering torque can be calculated using the data of the number of teeth and the rotation angle of the detection gears of the two planetary gear units.

However, the configuration in which two planetary gear units are used leads to a relatively complicated structure and high cost associated with the above-mentioned conventional torque detection device. In addition, the calculation method for obtaining the steering torque is quite complicated.

It is therefore an object of the present invention to provide a torque detection device that can operate conveniently and enable linear amplification of the detection range to increase detection accuracy.

Thus, the torque detection device is mounted on the torque transmission device. The torque transfer device includes a rotatable input and output shaft. The torque detection device includes an input gear to be sleeved on an input shaft, an output gear to be sleeved on an output shaft, and a planetary gear unit.

The planetary gear unit includes a ring gear meshing with the input gear, a sun gear arranged on the ring gear, a conveying gear meshing with the output gear, and a plurality of planetary gears. The planetary gear is rotatably coupled to the carrier gear, and is disposed between the sun gear and the ring gear. The planetary gear meshes with the ring gear and the sun gear, and when the input gear rotates in the rotational direction with respect to the output gear by the first angle, Is driven to rotate in the opposite rotational direction by a second angle larger than the first angle.

Thanks to the presence of the planetary gear unit and the arrangement between the ring gear, the sun gear, the planetary gear, the carrier gear, the input gear and the internal teeth of the output gear, the additional rotation angle between the input shaft and the output shaft is magnified through the sun gear So that torque calculation can be facilitated and linear amplification of the detection range is possible, which can increase the detection accuracy.

Other features and advantages of the present disclosure will become apparent from the following detailed description of embodiments with reference to the accompanying drawings.
1 is a perspective view of an EPS system.
2 is an exploded perspective view of a conventional torque detection device with a hole guidance system.
3 is a cross-sectional view of an embodiment of a torque detection device according to the present invention mounted on a torque transfer device.
4 is a perspective view of this embodiment.
5 is an exploded perspective view of this embodiment.
Figure 6 is a partial plan view of this embodiment.
7 is a cross-sectional view of this embodiment.
8 is a schematic view illustrating the structural relationship between the first gear, the second gear, the output gear, and the conveying gear of this embodiment.

3, 4 and 5, an embodiment of the torque detection device 200 according to the present invention is mounted on the torque transfer device 8. [ The torque transfer device 8 includes a rotatable input shaft 81, an output shaft 82 rotatable relative to the input shaft 81 and a torsion bar 82 connected between the input shaft 81 and the output shaft 82 83). The input shaft 81 has a first shaft main body 811 formed with pairs of first guide grooves 812. The output shaft 82 has a second shaft body 821 having a pair of second guide grooves 822 formed thereon.

The torsion bar 83 has the same physical characteristics as the torsion spring. That is, the torsion of the torsion bar 83 is equal to the product of the strength of the torsion bar 83 and the twist angle received by the torsion bar 83. A stopper mechanism (not shown) is arranged between the input shaft 81 and the output shaft 82 to limit the twist angle of the torsion bar 83 to a range generally between +/- 5 degrees.

When the output shaft 82 is unloaded, the output shaft 82 is rotatable together with the input shaft 81. That is, rotation of the input shaft 81 does not cause deformation of the torsion bar 83 when the steering force is applied.

When the output shaft 82 is restricted, rotation of the input shaft 81 when the steering force is applied causes deformation of the torsion bar 83 and causes the additional rotation angle of the input shaft 81 and the rotation angle of the output shaft 82 The torque of the input shaft 81 is linearly proportional.

The torque detection device 200 includes an input gear 2, an output gear 3, a planetary gear unit 4, a first angle sensing unit 5, a calculation unit 6 and a second angle sensing unit 7 .

The input gear 2 is sleeve-connected to the input shaft 81 and has a first extending hole 21 for extending the first shaft main body 811 of the input shaft 81 through the first shaft main body 811, And a pair of first protrusions 22 which are respectively coupled to the first guide grooves 812 and which are fastened to the first guide grooves 812.

The output gear 3 is sleeve-connected on the output shaft 82 and has a second extending hole 31 for extending the second shaft body 821 of the input shaft 81 and a second extending hole 31 and a second projection 32 which is to be fastened to the second guide groove 822, respectively.

5, 6 and 7, the planetary gear unit 4 includes a ring gear 41 meshing with the input gear 2, a sun gear 42 arranged on the ring gear 41, 3 and a ring gear 41 and a sun gear 42 which are rotatably coupled by a carrier gear 43 and are arranged between the sun gear 42 and the ring gear 41, And a plurality of planetary gears 44 engaged with the planetary gears 44. [

The ring gear 41 has a plurality of outer teeth 411 engaged with the input gear 2 and a plurality of inner teeth 412 engaged with the planetary gears 44.

The number of outer teeth 411 of the ring gear 41 is equal to the number of tooth teeth of the input gear 2. That is, it satisfies the relationship T _(E) = T _(I), where, T _(E) represents the number of the external tooth 411 of the ring gear (41), T _(I) is the input gear 2 The number of teeth of the tooth. In this embodiment, the outer teeth 411 of the ring gear 41 and the number of teeth of the input gear 2 are 62, respectively.

The number of internal teeth 412 of the ring gear 41 is the number of teeth of the predetermined constant times the number of sun gears 42 greater than one. That is, T _(R) = T _(S) satisfies the relationship × K, where T _(R) represents the number of the internal tooth 412 of the ring gear (41), T _(S) is the sun gear (42 ), And (K) represents a predetermined constant. In this embodiment, the number of teeth of the sun gear 42 is 6, the predetermined constant is 15, and the number of internal teeth 412 of the ring gear 41 is 90 pieces.

Outside of the transfer gear 43 has a plurality of external _{tooth, T (P) × K =} T (O) × (K + 1) and satisfies the relation, where, T _(P) of the conveying gear 43 And T _(O) represents the number of teeth of the output gear 3. [0035] In this embodiment, the number of external teeth of the conveying gear 43 is 64, and the number of teeth of the output gear 3 is 60.

The first angle sensing unit 5 comprises a first magnet 51 arranged on the sun gear 42 and a second magnet 51 arranged on the first gear 51 for sensing the angle at which the first magnet 51 rotates during rotation of the sun gear 42 And a first magnetic induction module (52).

The calculation unit 6 is electrically connected to the first angle detection unit 5 and detects the torque of the input shaft 81 with respect to the output shaft 82 with reference to the angle detected by the first angle detection unit 5 / RTI >

5, 6 and 8, the second angle sensing unit 7 includes first and second gears 71 and 72 engaged with the conveying gear 43, A third magnet 74 arranged on the second gear 72 and a second magnet 73 electrically connected to the calculation unit 6 and rotated during rotation of the first gear 71, And a second magnetic induction module 75 electrically connected to the calculation unit 6 and configured to detect an angle at which the third magnet 74 rotates during the rotation of the second gear 72 And a third magnetic induction module 76 arranged for sensing.

The number of teeth of the first gear 71 is different from the number of teeth of the second gear 72. In this example, the number of teeth of the first gear 71 is 19, and the number of teeth of the second gear 72 is 17.

5, 6 and 7, the calculation unit 6 includes an angle-second magnetic induction module 75 in which the second and third magnets 73 and 74 rotate respectively, (Not shown) of the torque transmission device 8, respectively.

3, 5 and 6, when the torque transfer device 8 is in use, the input shaft 81 is normally connected to the steering wheel (not shown) of the vehicle and the output shaft 82 is connected to the steering wheel And is usually connected to a steering box (not shown). When the output shaft 82 is unloaded, the rotation of the steering wheel will cause the input shaft 81 and the output shaft 82 to rotate together, and the relative rotation angle between the input shaft 81 and the output shaft 82 It will not exist. When an additional rotation angle of the input shaft 81 with respect to the output shaft 82, which is the twist angle of the torsion bar 83, is sensed, the output shaft 82 is restricted, The torque of the bar 83 can be calculated under the relationship that the torsion of the torsion bar 83 is equal to the product of the torsion angle of the torsion bar 83 and the strength of the torsion bar 83. [

With the engagement between the input gear 2 and the input shaft 81 and the engagement between the output gear 3 and the output shaft 82 the input and output gears 2 and 3 are connected to the input and output shafts 81 and 82 ). ≪ / RTI > In addition, the manufacturing cost of the input and output gears 2 and 3 is reduced due to the simple structure of the first projecting portion 22 of the input gear 2 and the second projecting portion 32 of the output gear 3.

The ring gear 41 and the conveying gear 43 are respectively driven to rotate by the input shaft 81 and the output shaft 82 to rotate the input shaft 81 and the output shaft 82, 44 to drive the rotation of the sun gear 42.

According to the first equation for the planetary gear unit 4:

_{ψ (S) = ((T} (R) / T (s)) + 1) ψ (P) - (T (R) / T (s)) ψ (R)

Here, T _(s) is a solar number of tooth of the gear 42. As mentioned previously, T _(R) is the number of the internal tooth 412 of the ring gear 41. As previously mentioned, ψ _{( S} is the rotation angle of the sun gear 42 and _P is the rotation angle of the carrier gear 43 and _R is the rotation angle of the ring gear 41.

When the output shaft 82 is rotatable together with the input shaft 81, the number of teeth of the sun gear 42 is 6 and the number of internal teeth 412 of the ring gear 41 is 90, _(S) = 16? _(P) - 15? _(R) .

The rotational angle of the carrier gear 43 and the rotational angle of the ring gear 41 are designed so as to satisfy the third equation of? _(P) /? _(R) = 15/16. Therefore, when replacing the relationship with the second equation, the rotation angle of the sun gear 42 can be induced to 0 DEG, which means that the sun gear 42 does not rotate, The first magnet 51 arranged on the first magnet 42 does not rotate. The torque of the input shaft 81 with respect to the output shaft 82, which is sensed by the first magnetic induction module 52 in accordance with the angle at which the first magnet 51 rotates, .

When the output shaft 82 is restricted and the steering force is applied to the input shaft 81 and is rotated by an additional rotation angle C with respect to the output shaft 82, And the ring gear 41 rotates by an additional rotation angle C with respect to the conveying gear 43 so that ψ _(S) = 16ψ _(P) - 15 (? _(R) + C). By replacing the third equation with the fourth equation, a fifth equation of? _(S) = -15C can be obtained, which means that the rotation angle of the sun gear 42 is the additional rotation angle C And the rotational direction of the sun gear 42 is opposite to the rotational direction of the input shaft 81. [ The relative rotation angle C between the input shaft 81 and the output shaft 82 is enlarged through the rotation angle of the sun gear 42. [ At this moment, the first magnet 51 rotates during the rotation of the sun gear 42, and when the first magnetic induction module 52 detects the rotation angle of the first magnet 51, The torque of the input shaft 81 relative to the input shaft 81 can be calculated by the calculation unit 6. In this embodiment, the rotation range of the sun gear 42 is designed to be +/- 120 °, which means that the range of the additional rotation angle C is +/- 8 °. The aforementioned twist angle of the torsion bar 83 is limited to between +/- 5 degrees, so that it does not exceed the range limit of the further rotation angle C.

In addition, during the above-mentioned movement of the torque transfer device 8, since the rotation of the conveying gear 43 drives the rotation of the first gear 71 and the second gear 72, The rotation angles of the second magnet 73 and the third magnet 74 are not the same because the number of teeth between the second gears 72 is not the same. The rotation angles of the second magnet 73 and the third magnet 74 are sensed by the second magnetic induction module 75 and the third magnetic induction module 76 respectively and the calculation unit 6 calculates the rotation angle The angle at which the torque transfer device 8 rotates is determined by referring to the angle sensed by the first and second gears 73 and 74 and the number of teeth between the first gear 71 and the second gear 72 Can be calculated.

Briefly, when the number of teeth of the first gear 71 is 19 and the number of teeth of the second gear 72 is 17, when the first gear 71 rotates for seventeen turns, (72) is rotated during the 19th rotation. At this moment, the first gear 71 and the second gear 72 move to their original positions, respectively. Therefore, by sensing the difference in rotational angle between the second magnet 73 and the third magnet 74, the angle at which the torque transmitting device 8 rotates can be calculated.

In this embodiment, since the ratio of the number of teeth between the conveying gear 43 and the output gear 3 is 64/60, the ratio of the rotational speed is 60/64, that is, 0.9375. The output gear 3 is in the range of at least 800 ° to -800 ° (that is, the range of the rotation angle of the output gear 3 is at least 1600 °) (1900 x 0.9375) ° and (3000 x 0.9375) degrees, that is, 1781 (3000 x 0.9375) degrees, when the rotation angle of the conveying gear 43 is set to be exemplified as having a range of rotation angles between 1900 ° and 3000 °. ° and 2812 °, which is again expressed in terms of the number of revolutions, the rotation in which the conveying gear 43 rotates is in the range of 1781/360 and 2812/360, that is, 4.9 to 7.8.

As such, the least common multiple of the number of teeth of the first gear 71 and the second gear 72 should be between (4.9 x 64) and (7.8 x 64), that is, between 314 and 499. 323, the number of teeth of the first gear 71 is set to 17, and the number of teeth of the second gear 72 is set to 19.

The integration between the input gear 2 and the ring gear 41 and the integration between the output gear 3 and the planetary gear 44 can be realized by pulleys and belts or by means of a chain saw It should be noted in this specification that wheel and chain could be realized, and these realizations can produce similar effects.

In addition, apart from those disclosed in this embodiment for the number of teeth assigned to the integrated gear pair, a different number of sets can be assigned as long as a similar effect is achieved. Further, in this embodiment, all gears are made of plastic material, but what is disclosed herein should not be imposed as a limitation of implementation.

In practical applications, the torque detection device can be applied to various electric powered vehicles such as electric bicycles, electric wheelchairs, and the like.

From the foregoing, the torque detection device according to the present invention provides the following advantages:

(1) The torque detection device can magnify the additional rotation angle (C) sensed by a factor of 15, so that the detection range is enlarged, and the sensing accuracy is improved compared to the conventional Hall element type torque detection device disclosed in the prior art It is significantly improved.

(2) The torque detection device enlarges the additional rotation angle C through the mechanical mechanism, thereby avoiding the possibility that the conventional Hall element type torque detection device malfunctions due to external electrical interference.

(3) Since the additional rotation angle of the detected conventional Hall element type torque detection device is very small, the requirements of the precision and structural configuration of the Hall element are higher. In addition, the design of the claw-shaped stator requires magnetic circuit analysis and therefore results in a high degree of difficulty associated with the manufacturing process. In addition, the production of the claw-shaped stator is easily deformed during assembly. In contrast, the operation of the present invention is performed by plastic gears, and since the manufacture of plastic gears is a very mature technology, the design and manufacture of the torque sensing device of the present invention is relatively easy.

(4) In comparison with other conventional torque detecting devices provided with two planetary gear units, the torque detecting device of the present invention having a single planetary gear unit has a simpler structure and can operate more easily. In addition, the calculation method for obtaining the steering torque is relatively easy.

In summary, the presence of the planetary gear unit 4 and the relationship between the presence of the internal tooth 412, the sun gear 42, the planetary gear 44, the conveying gear 43, the input gear 2, and the output gear 3 The additional rotation angle C between the input shaft 81 and the output shaft 82 can be enlarged through the sun gear 42 to facilitate torque calculation, It is possible to avoid the disadvantages of high cost due to the high precision of the hall element and the high requirement of the structural constitution associated with the conventional torque detecting device. In addition, compared with other conventional torque detection devices provided with two planetary gear units, the torque detection device of the present invention having a single planetary gear unit has a simpler structure and can operate more easily.

Although the present disclosure has been described in connection with what is considered to be an exemplary embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but covers all such variations and equivalent arrangements, You must understand that you want to.

Claims (10)

A torque detecting device to be mounted on a torque transmitting device including a rotatable input shaft and an output shaft, the torque detecting device comprising:
An input gear that is sleeved on the input shaft;
An output gear which is sleeved on the output shaft; And
Wherein the planetary gear unit comprises a planetary gear unit,
A ring gear engaged with the input gear,
A sun gear arranged on the ring gear,
A conveying gear engaged with the output gear, and
A plurality of planetary gears rotatably coupled to the carrier gear and arranged between the sun gear and the ring gear and meshing with the ring gear and the sun gear, The sun gear being driven to rotate in a direction opposite to the first direction by a second angle larger than the first angle,
The second angle being a predetermined constant greater than one, the first angle being multiplied;
The ring gear having a plurality of outer teeth for engaging the input gear and a plurality of inner teeth for engaging the planetary gears;
T satisfy the relation of _{(E) = T (I)} , T (R) = T (S) × K, and _{T (P) × K = T} (O) × (K + 1) , where, T _{( E)} denotes the number of the outer tooth of the ring gear, T _(I) denotes the number of tooth of the input gear, T _(R) represents a number of the internal tooth of the ring gear, T _{(S )} denotes the number of tooth of the sun gear, (K) denotes a predetermined constant, T _(P) denotes the number of tooth of the transfer gear, T _(O) is the number of tooth of the output gear And,
The input gear includes a first elongated hole for extending the first shaft body of the input shaft and a first elongated hole projecting inward into the first elongated hole and fastened to a first guide groove formed in the first shaft body. 1 protrusion;
Wherein the output gear includes a second extension hole for extending the second shaft body of the input shaft and a second guide hole projecting inward into the second extension hole and fastened to a second guide groove formed in the second shaft body, 2 protrusions. delete A first magnetic sensing module having a first magnet arranged on the sun gear and a first magnetic induction module arranged to sense an angle at which the first magnet rotates during rotation of the sun gear, ; And
Further comprising a calculation unit electrically connected to the first angle sensing unit and arranged to calculate a torque of the input shaft relative to the output shaft with reference to an angle sensed by the first angle sensing unit, Detection device. 4. The apparatus according to claim 3, further comprising a second angle sensing unit including first and second gears meshing with the conveying gear, the number of teeth of the first gear being different from the number of teeth of the second gear, Torque detection device. 5. The apparatus of claim 4, wherein the second angle sensing unit comprises:
A second magnet arranged on the first gear;
A third magnet arranged on the second gear;
A second magnetic induction module electrically connected to the calculation unit and arranged to sense an angle at which the second magnet rotates during rotation of the first gear; And
And a third magnetic induction module electrically connected to the calculation unit and arranged to sense an angle at which the third magnet rotates during rotation of the second gear,
Wherein the calculation unit is arranged to calculate an angle at which the output shaft rotates with reference to an angle sensed by the second and third magnetic induction modules. 5. The planetary gear set according to claim 4, wherein the number of teeth of the first gear is 19;
And the number of teeth of the second gear is 17. The torque detection device of claim 1, wherein the predetermined constant is 15. 4. The planetary gearset of claim 1, wherein the number of external threads and the number of threads of the input gear of the ring gear are 62, respectively;
The number of teeth of the sun gear is 6;
The number of the internal teeth of the ring gear is 90;
The number of teeth of the conveying gear is 64;
And the number of teeth of the output gear is 60. The torque detection device of claim 1, delete The torque detecting device according to claim 1, wherein the throwing of the conveying gear is formed on an outer peripheral surface of the conveying gear.

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