JP2022034835A - Manufacturing method of torque measuring device and torque load member - Google Patents

Abstract

To realize a configuration of a torque measuring device capable of measuring not only the torque applied to a torque load member but also rotation speed of the torque load member.SOLUTION: The torque measuring device includes a rotation center axis X, a rotation axis 1 having an annular surface to be detected 5 centered on the rotation center axis X, and a magnetostrictive torque sensor 3 having a detection unit 14 composed of a coil facing the surface to be detected 5. The surface to be detected 5 has a shot peening processing unit 26 only at one or a plurality of locations in the circumferential direction. The detection unit 14 is arranged only in a part of the circumferential direction range about the rotation center axis X.SELECTED DRAWING: Figure 2

Description

The present invention relates to a torque measuring device used for measuring torque and a method for manufacturing a torque load member to which torque is applied.

In recent years, in the field of automobiles, the torque transmitted by the rotating shaft that constitutes the power train (power transmission mechanism) is measured, and the measurement results are used to control the output of the engine or electric motor that is the power source. Development of a system for executing shift control of a transmission is in progress.

Further, conventionally, as a device for measuring torque transmitted by a torque load member such as a rotating shaft, a magnetic strain type torque measuring device is known (for example, Japanese Patent Application Laid-Open No. 2017-96825 (Patent Document 1). See Japanese Patent Application Laid-Open No. 2017-96826 (Patent Document 2), Japanese Patent Application Laid-Open No. 7-10011 (Patent Document 3), and Japanese Patent Application Laid-Open No. 2018-112451 (Patent Document 4). In the magnetostriction type torque measuring device, the torque is measured by utilizing a phenomenon (reverse magnetostriction effect) in which the magnetic permeability of the torque load member changes according to the applied torque. Specifically, a coil facing the detected surface of the torque load member is AC-excited, and the magnetic flux generated around the coil is passed through the surface layer portion of the detected surface. Then, the torque applied to the torque load member is measured as a change in the magnetic permeability of the surface layer portion of the detected surface, that is, a change in the self-inductance of the coil. A torque sensor provided with such a coil is called a magnetostrictive torque sensor.

JP-A-2017-96825 Japanese Unexamined Patent Publication No. 2017-96826 Special Fair 7-10011 Gazette Japanese Unexamined Patent Publication No. 2018-114251

By the way, in the field of automobiles, it is generally practiced to measure the rotation speed of a rotating shaft or the like constituting a power train and utilize the measurement result for vehicle control. Therefore, if not only the torque but also the rotation speed can be measured by the magnetostriction type torque measuring device as described above, the number of measuring devices mounted on the vehicle can be reduced. However, in the conventional magnetic strain type torque measuring device, the self-inductance of the coil does not change only by changing the rotation speed of the torque load member such as the rotating shaft, so that the rotation speed of the torque load member cannot be measured.

In view of the above circumstances, it is an object of the present invention to realize a structure capable of measuring not only the torque applied to the torque load member but also the rotation speed of the torque load member.

The torque measuring device of the present invention has a torque load member having a rotation center axis and an annular (for example, cylindrical surface or annular surface) detected surface centered on the rotation center axis, and the detected surface. It is provided with a magnetic distortion type torque sensor having a coil facing the center.
The surface to be detected has shot peening processing units only at one or a plurality of locations in the circumferential direction. The shot peening processing unit is a portion to which shot peening processing has been performed.
The coil is arranged only in a part of the circumferential direction centered on the rotation center axis.

In one aspect of the torque measuring device of the present invention, the shot peening processing units are arranged at a plurality of locations at equal intervals in the circumferential direction.

In one aspect of the torque measuring device of the present invention, the shot peening processing unit covers the area to be detected in a circumferential direction of 30% or more (more preferably 50% or more, still more preferably 70% or more) with respect to the entire circumference. Exists.

In one aspect of the torque measuring device of the present invention, a rolling bearing that rotatably supports the torque load member is further provided, and the torque sensor is supported by the rolling bearing.
In this case, the torque sensor can be directly or indirectly supported by another member such as a sensor holder with respect to the stationary wheel provided in the rolling bearing which does not rotate even when used.

The torque load member to be manufactured according to the present invention includes a rotation center axis and an annular detected surface centered on the rotation center axis, and the detected surface is located at one or a plurality of locations in the circumferential direction. Only has a shot peening processing unit.

The first aspect of the method for manufacturing a torque load member of the present invention is to expose only one or a plurality of points in the circumferential direction in a portion of the intermediate material of the torque load member on which the surface to be detected is to be formed. A step of forming the shot peening processing unit only at the one or a plurality of locations by performing the shot peening processing with the remaining portions masked is provided.

A second aspect of the method for manufacturing a torque load member of the present invention relates to the circumferential direction after shot peening treatment is applied to the portion of the intermediate material of the torque load member to which the surface to be detected is to be formed. The present invention comprises a step of removing only the surface layer portion of a portion deviated from the one or a plurality of locations to use only the one or a plurality of locations as the shot peening processing portion.

According to the torque measuring device of the present invention, not only the torque applied to the torque load member but also the rotation speed of the torque load member can be measured.

FIG. 1 is a partially cut side view of a torque measuring device according to the first example of the embodiment. 2A is a side view showing only the rotation shaft and the torque sensor taken out from the torque measuring device shown in FIG. 1, and FIG. 2B is a sectional view taken along the line AA of FIG. 2A. be. FIG. 3 is a developed view of the first to fourth coil layers constituting the detection unit of the torque sensor as viewed from the outside in the radial direction. 4 (a) to 4 (d) are development views of the first to fourth coil layers constituting the detection unit of the torque sensor as a single unit as viewed from the outside in the radial direction. FIG. 5 is a diagram showing a bridge circuit including the first to fourth coil layers constituting the detection unit of the torque sensor. 6 (a) and 6 (b) are views regarding the first example of the embodiment, and specifically, FIG. 6 (a) shows a shot pinning process of the detection unit of the torque sensor and the surface to be detected. 2A is a cross-sectional view taken along the line AA of FIG. 2A showing a positional relationship in which the portions face each other in the radial direction. FIG. 2A is a cross-sectional view taken along the line AA of FIG. 2A showing a positional relationship in which and do not face each other in the radial direction. FIG. 7 (a) is a diagram showing a time change of the sensor output of the first example of the embodiment, and FIG. 7 (b) is a diagram showing a time change of the sensor output of the comparative example. 8 (a) is a diagram corresponding to FIG. 2 (a) showing a second example of the embodiment, and FIG. 8 (b) is a sectional view taken along the line BB of FIG. 8 (a). 9 (a) and 9 (b) are views regarding the second example of the embodiment, and specifically, FIG. 9 (a) shows the circumferential direction of the detection unit of the torque sensor and the surface to be detected. FIG. 9B is a cross-sectional view taken along the line BB of FIG. 8A showing the positional relationship in which the five shot peening processing portions face each other in the radial direction, and FIG. 9B shows the detection portion of the torque sensor and the detected portion. FIG. 8B is a cross-sectional view taken along the line BB of FIG. 8A showing a positional relationship in which four shot peening processing portions in the circumferential direction of the surface face each other in the radial direction.

[First example of the embodiment]
The first example of the embodiment will be described with reference to FIGS. 1 to 7.
FIG. 1 shows a torque measuring device. This torque measuring device includes a rotating shaft 1 corresponding to a torque load member, a rolling bearing 2, and a magnetostrictive torque sensor 3.

In the following description of this example, regarding the torque measuring device, one side in the axial direction is the right side in FIG. 1, and the other side in the axial direction is the left side in FIG.

The rotary shaft 1 is a torque transmission shaft such as a rotary shaft of a transmission, a rotary shaft of a differential gear, a propeller shaft, and a drive shaft, which constitutes a power train of an automobile, and has a rotation center shaft X. The rotation axis 1 is formed in a columnar shape centered on the rotation center axis X. The rotation axis may be configured in a cylindrical shape centered on the rotation center axis X, for example. The rotary shaft 1 is made of a material having magnetic strain characteristics, and in this example, it is made of steel (iron alloy) such as SCr420 (chrome steel), SCM420 (chrome molybdenum steel), and SNCM420 (nickel chrome molybdenum steel).

The rotation axis 1 has a cylindrical inner ring track 4 centered on the rotation center axis X on a partial outer peripheral surface in the axial direction. The rotating shaft 1 rotates on a portion of the outer peripheral surface adjacent to one side of the inner ring track 4 in the axial direction (a portion sandwiched between the two chain lines α in FIGS. 1 and 2A). It has a cylindrical surface to be detected 5 centered on the central axis X.

The surface to be detected 5 is provided with a diagonal grid in the shot peening processing unit 26 (FIGS. 1, FIG. 2 (a), and FIG. 2 (b)), which is a portion to which the shot peening process is applied only at one position in the circumferential direction. A portion), and a shot peening non-processed portion 27 which is a portion not subjected to the shot peening process is provided at the remaining circumferential direction portion. In this example, on the surface to be detected 5, the shot peening processing unit 26 exists in a circumferential direction range of 50% of the entire circumference (circumferential direction range with a central angle of 180 degrees), and is a shot peening non-processing unit. 27 exists in the circumferential range of the remaining 50% of the entire circumference. However, when the present invention is carried out, the shot peening processing unit 26 may be present in a smaller or larger circumferential range than in the case of this example. However, from the viewpoint of ensuring a large level of output V, which will be described later, the shot peening processing unit has a circumference of 30% or more (more preferably 50% or more, still more preferably 70% or more) with respect to the entire circumference on the detected surface. It is better to be in the directional range.

The rotating shaft 1 is rotatably supported by a rolling bearing 2 with respect to a stationary member that does not rotate when used, such as a housing constituting a power train of an automobile, about a rotation center axis X.

The rolling bearing 2 is a needle bearing and includes an outer ring 6, which is a stationary ring that does not rotate even when used, a plurality of needles 7, and a cage 8.

The outer ring 6 is made of steel such as bearing steel and has a cylindrical shape. The outer ring 6 has an inward flange portion 9 bent inward in the radial direction at both ends in the axial direction. The outer ring 6 has a cylindrical outer ring track 10 on the inner peripheral surface of the axial intermediate portion sandwiched between the pair of inward flange portions 9. Such an outer ring 6 is fitted inside a stationary member such as a housing constituting the power train of an automobile, and does not rotate even during use. Each of the plurality of needles 7 is made of steel such as bearing steel and is formed in a columnar shape. These needles 7 are rotatably arranged between the outer ring track 10 and the inner ring track 4. The cage 8 is made of steel or synthetic resin and has a cylindrical shape. The cage 8 has pockets at a plurality of positions in the circumferential direction, and the needles 7 are rotatably held one by one in these pockets.

The torque sensor 3 is supported by the outer ring 6 via the sensor holder 11. The sensor holder 11 is formed of a metal, a synthetic resin, or the like in a cylindrical shape, and is attached to the outer ring 6 in a state of being adjacent to one side in the axial direction of the outer ring 6. For this purpose, specifically, the fitting cylinder portion 12 provided on the other end in the axial direction of the sensor holder 11 is internally fitted and fixed to the inward flange 9 on the one side in the axial direction of the outer ring 6. The sensor holder can also be integrally formed with the outer ring 6.

The torque sensor 3 includes a cylindrical back yoke 13 made of a magnetic material, and a detection unit 14 held and fixed to the inside of the back yoke 13 in the radial direction by an appropriate fixing means such as adhesion. Such a torque sensor 3 is arranged coaxially with the detected surface 5 around the detected surface 5 of the rotation shaft 1, that is, a state in which the detected unit 14 is radially opposed to the detected surface 5. Therefore, it is internally fitted and held in the sensor holder 11.

The detection unit 14 is configured to include a large number of coils (first to fourth detection coils 19 to 22), and is arranged only in a part of the circumferential direction range centered on the rotation center axis X of the rotation axis 1. There is. That is, the detection unit 14 is configured in a partially cylindrical shape. In particular, in this example, the detection unit 14 is configured in a semi-cylindrical shape, and is arranged in a circumferential direction range in which the central angle of the rotation axis 1 about the rotation center axis X is 180 degrees. However, when the present invention is carried out, the detection unit 14 may be arranged in a smaller or larger circumferential range than in the case of this example. Further, in this example, the back yoke 13 is formed in a cylindrical shape, but in the case of carrying out the present invention, the back yoke is made into a partial cylindrical shape existing only in the same circumferential range as the detection unit 14. It can also be configured.

As shown in FIG. 2B, the detection unit 14 includes first to fourth coil layers 15 to 18, each of which is four coil layers configured in a cylindrical shape. The first to fourth coil layers 15 to 18 are arranged in the order of the first coil layer 15, the second coil layer 16, the third coil layer 17, and the fourth coil layer 18 from the inside in the radial direction in the radial direction. It is arranged in layers. The first coil layer 15 and the second coil layer 16 are formed separately on one side surface and the other side surface of a strip-shaped flexible substrate (not shown), and the flexible substrate is curved into a semi-cylindrical shape to form a semi-cylindrical shape. It is structured like a cylinder. The third coil layer 17 and the fourth coil layer 18 are formed separately from one side surface and the other side surface of another strip-shaped flexible substrate (not shown), and the flexible substrate is curved into a semi-cylindrical shape. It is configured in a semi-cylindrical shape. An insulating layer is provided between the second coil layer 16 and the third coil layer 17.

FIG. 3 shows a developed view of the detection unit 14 as viewed from the outside in the radial direction. 4 (a) to 4 (d) show development views of the first to fourth coil layers 15 to 18 constituting the detection unit 14 individually viewed from the outside in the radial direction.

As shown in FIG. 4A, the first coil layer 15 includes a plurality of first detection coils 19. These first detection coils 19 are arranged side by side at equal pitches in the circumferential direction. In these first detection coils 19, adjacent ones in the circumferential direction are connected in series.

As shown in FIG. 4B, the second coil layer 16 includes a plurality of second detection coils 20. These second detection coils 20 are arranged side by side at equal pitches in the circumferential direction. In these second detection coils 20, adjacent ones in the circumferential direction are connected in series.

As shown in FIG. 4C, the third coil layer 17 includes a plurality of third detection coils 21. These third detection coils 21 are arranged side by side at equal pitches in the circumferential direction. These third detection coils 21 are connected in series to each other adjacent to each other in the circumferential direction.

As shown in FIG. 4D, the fourth coil layer 18 includes a plurality of fourth detection coils 22. These fourth detection coils 22 are arranged side by side at equal pitches in the circumferential direction. These fourth detection coils 22 are connected in series to each other adjacent to each other in the circumferential direction.

Each of the first detection coil 19 and the fourth detection coil 22 is configured to include wiring inclined by + 45 ° with respect to the axial direction of the rotating shaft 1 on both sides in the circumferential direction. On the other hand, each of the second detection coil 20 and the third detection coil 21 is configured to include wiring inclined by −45 ° with respect to the axial direction of the rotating shaft 1 on both sides in the circumferential direction.

In this example, each of the first to fourth coil layers 15 to 18 is formed on the side surface of the flexible substrate, but each of the first to fourth coil layers has a conducting wire connected to a support member such as a bobbin. It can also be configured by wrapping.

The first to fourth coil layers 15 to 18 constitute a bridge circuit 23 as shown in FIG. The bridge circuit 23 includes the first to fourth coil layers 15 to 18, the oscillator 24 for applying an AC voltage between points A and B, and the potential difference between points C and D (middle). It is configured to include a lock-in amplifier 25 for detecting and amplifying (point voltage, differential voltage).

In the method of manufacturing the rotating shaft 1 constituting the torque measuring device of this example as described above, the surface to be detected 5 is formed as follows. That is, one of a portion of the outer peripheral surface of the intermediate material obtained when the rotating shaft 1 is manufactured, a portion on which the detected surface 5 should be formed, and a portion around the portion on which the detected surface 5 should be formed. The shot peening process is performed with only the circumferential portion of the portion exposed and the remaining portion masked. As a result, the shot peening processing unit 26 is formed only in the circumferential direction portion of the portion where the detected surface 5 should be formed, and the remaining circumferential direction portion is designated as the shot peening non-processing portion 27. As a result, the surface to be detected 5 is formed.

In addition, when carrying out this invention, the detected surface 5 can also be formed as follows. That is, the shot peening process is applied to the entire portion of the outer peripheral surface of the intermediate material obtained when the rotating shaft 1 is manufactured, where the surface to be detected 5 should be formed. After that, the surface layer portion (for example, the portion from the surface to 100 to 200 μm) of the circumferential direction portion deviated from the circumferential direction portion of the portion where the detected surface 5 should be formed is removed by cutting or the like. The surface to be detected 5 is formed by using only a part of the circumferential direction portion as the shot peening processing unit 26 and the portion where the surface layer portion is removed as the shot peening non-processing portion 27.

When using the torque measuring device of this example, an AC voltage is applied between points A and B of the bridge circuit 23 by the oscillator 24, and an AC current is passed through the first to fourth coil layers 15 to 18. Then, in the first to fourth coil layers 15 to 18, the detection coils 19 to adjacent to each other in the circumferential direction are shown by arrows a, b, c, and d in FIGS. 4 (a) to 4 (d). Currents in opposite directions flow between the 22s. In other words, each detection coil 19 to 22 is wound so that a current in such a direction flows. As a result, an AC magnetic field is generated around the first to fourth coil layers 15 to 18, and the magnetic flux of the AC magnetic field passes through the surface layer portion of the detected surface 5 of the rotating shaft 1.

In this state, when the torque T in the direction shown in FIG. 2A is applied to the rotating shaft 1, the rotating shaft 1 has a tensile stress (+ σ) in the + 45 ° direction with respect to the axial direction and a tensile stress (+ σ) with respect to the axial direction. The compressive stress (-σ) in the -45 ° direction acts. Then, due to the inverse magnetostrictive effect, the magnetic permeability of the rotating shaft 1 increases in the + 45 ° direction in which the tensile stress (+ σ) acts, and in the −45 ° direction in which the compressive stress (−σ) acts. , The magnetic permeability of the rotating shaft 1 decreases.

On the other hand, the first coil layer 15 and the fourth coil layer 18 are configured to include a wiring inclined by + 45 ° with respect to the axial direction of the rotating shaft 1, and one of the magnetic fluxes of the AC magnetic field generated around the wiring. The portion passes through the surface layer portion of the surface to be detected 5 of the rotating shaft 1 in the −45 ° direction in which the magnetic permeability decreases. Therefore, the self-inductances of the first coil layer 15 and the fourth coil layer 18 are reduced, respectively. The second coil layer 16 and the third coil layer 17 are configured to include a wiring inclined by −45 ° with respect to the axial direction of the rotating shaft 1, and are a part of the magnetic flux of the AC magnetic field generated around the wiring. Passes through the surface layer portion of the detected surface 5 of the rotating shaft 1 in the + 45 ° direction in which the magnetic permeability increases. Therefore, the self-inductance of the second coil layer 16 and the third coil layer 17 increases, respectively.

On the other hand, when the torque T in the direction opposite to the direction shown in FIG. 2A is applied to the rotation shaft 1, the first coil layer 15 and the fourth coil layer 18 have the opposite action to the above-mentioned case. The self-inductance increases, and the self-inductance of the second coil layer 16 and the third coil layer 17 decreases.

In any case, in the bridge circuit 23, the potential difference (midpoint voltage, differential voltage) between the points C and D is detected and amplified by the lock-in amplifier 25, so that the rotation shaft 1 is loaded. An output V corresponding to the direction and magnitude of the torque T can be obtained.

Further, in the structure of this example, when the rotation shaft 1 is rotating, the output V (sensor output) of the bridge circuit 23 is, for example, even if the torque T loaded on the rotation shaft 1 is constant. It changes periodically as shown in FIG. 7 (a). Next, the reason for this will be described.

In the structure of this example, the detected surface 5 of the rotating shaft 1 has a shot peening processing unit 26 at only one location in the circumferential direction, and a shot peening non-processing unit 27 at the remaining circumferential direction. Further, the detection unit 14 of the torque sensor 3 is arranged only in a part of the circumferential direction range centered on the rotation center axis X of the rotation axis 1. Therefore, in the structure of this example, the shot peening processing unit 26 and the shot peening non-processing unit 27 alternately pass through the portion facing the detection unit 14 as the rotation shaft 1 rotates.

On the other hand, on the surface to be detected 5, the shot peening processing unit 26 has improved magnetostrictive characteristics as compared with the shot peening non-processing unit 27, and when the detection unit 14 faces the shot peening processing unit 26, Compared with the case where the detection unit 14 faces the shot peening non-processing unit 27, the output V of the bridge circuit 23 becomes larger and the torque detection sensitivity is improved. There are various reasons for obtaining such an effect, as described in, for example, Japanese Patent Application Laid-Open No. 7-10011 and JP-A-2018-112541, but the reason itself is the present invention. Since it is not a feature, the description is omitted.

In any case, in the structure of this example, when the detection unit 14 of the torque sensor 3 faces the shot peening processing unit 26, the detection unit 14 of the torque sensor 3 faces the shot peening non-processing unit 27. The output V of the bridge circuit 23 becomes larger than that of the case where the bridge circuit 23 is used. Therefore, when the shot peening processing unit 26 and the shot peening non-processing unit 27 alternately pass through the portion facing the detection unit 14 as the rotation shaft 1 rotates, the output V of the bridge circuit 23 becomes. For example, it changes periodically as shown in FIG. 7 (a).

In the output V shown in FIG. 7A, the maximum value (peak value) V _max is, as shown in FIG. 6A, in the portion of the surface to be detected 5 where the detection unit 14 faces. , The value in the state where the ratio of the shot peening processing unit 26 is the maximum (100% in this example). On the other hand, as shown in FIG. 6B, the minimum value V _min is the minimum ratio of the shot peening processing unit 26 in the portion of the detected surface 5 facing the detection unit 14 (this example). Then, it is the value in the state where it becomes 0%).

In the structure of this example, the level of the output V (for example, the maximum value V _max , the average value, etc.) increases as the torque T loaded on the rotation shaft 1 increases. Therefore, the magnitude of the torque T can be measured based on the level of the output V. Further, the polarity (±) of the output V changes depending on the direction of the torque T. Therefore, the direction of the torque T can be grasped based on the polarity (±) of the output V.

Further, in the structure of this example, the frequency (period) of the output V changes depending on the rotation speed of the rotation axis 1. Therefore, the rotation speed can be measured based on the frequency (period) of the output V.

In the structure of the comparative example in which the entire circumference of the detected surface is a shot peening processing unit (or a shot peening non-processing unit), when the torque T is constant, the output of the torque sensor is output even if the rotation shaft rotates. V becomes a constant value as shown in FIG. 7 (b). Therefore, it is not possible to measure the rotation speed of the rotating shaft based on the output V.

If the torque measuring device of this example as described above is mounted on the vehicle, the measured torque T and the rotational speed can be utilized for vehicle control. Further, according to the torque measuring device of this example, not only the torque T but also the rotation speed can be measured, so that the number of measuring devices mounted on the vehicle can be reduced.

[Second example of the embodiment]
A second example of the embodiment will be described with reference to FIGS. 8 and 9.

In the structure of this example, the detected surface 5a of the rotating shaft 1 is provided with shot peening processing units 26 at a plurality of locations (8 locations in the illustrated example) at equal intervals in the circumferential direction. In other words, the detected surface 5a includes a plurality of shot peening processing units 26 and shot peening non-processing units 27 (eight in the illustrated example), and the shot peening processing unit 26 and the shot peening non-processing unit 27. And are arranged alternately and at equal pitches in the circumferential direction. Further, even in the structure of this example, the detection unit 14a of the torque sensor 3 is arranged only in a part of the circumferential direction range (in the illustrated example, the circumferential direction range having a central angle of about 205 degrees). When the present invention is carried out, the number of shot peening processing units 26 (shot peening non-processing units 27) included in the detected surface 5a can be smaller or larger than in the case of this example. Further, when the present invention is carried out, the detection unit 14a may be arranged in a smaller or larger circumferential direction range than in the case of this example.

Even in the structure of this example as described above, the ratio of the shot peening processing unit 26 in the portion of the detected surface 5a facing the detection unit 14a changes periodically with the rotation of the rotation shaft 1. .. Specifically, as shown in FIG. 9A, as the rotation axis 1 rotates, the shot peening processing units 26 at five locations face the detection unit 14a, and as shown in FIG. 9B. In addition, the state in which the four shot peening processing units 26 face the detection unit 14a is alternately repeated. Along with this, the output V of the bridge circuit 23 changes periodically. Therefore, the rotation speed of the rotation shaft 1 can be measured based on the frequency (period) of the output V.

In particular, in the structure of this example, since the shot peening processing portions 26 of the surface to be detected 5a are present at a plurality of locations in the circumferential direction, the shot peening processing unit 26 is detected as in the structure of the first example of the embodiment (see, for example, FIG. 2). Compared with the case where the shot peening processing unit 26 on the surface 5 exists only at one position in the circumferential direction, the frequency of the output V when the rotation shaft 1 rotates can be increased (period is shortened). Therefore, in the structure of this example, the change in the rotation speed of the rotation axis 1 can be detected at a shorter time interval than the structure of the first example of the embodiment.
Other configurations and effects are the same as in the first embodiment.

When the present invention is carried out, the coils constituting the magnetostrictive torque sensor may be arranged at a plurality of locations in the circumferential direction (for example, two locations on opposite sides in the radial direction).

The torque load member that is the subject of the present invention is not limited to the rotation shaft, and may be, for example, a sleeve that is externally fitted and fixed to the rotation shaft and to which torque is applied together with the rotation shaft.

The torque load member is not limited to a member having a detected surface on the peripheral surface, and the detected surface is provided on an axial side surface as described in, for example, JP-A-2017-96825 and JP-A-2017-96828. It can also be a member to have.

When the torque load member of the present invention is incorporated into a power train of an automobile and used, the target device is not particularly limited. For example, manual transmission (MT), automatic transmission (AT), belt type continuously variable transmission, toroidal type continuously variable transmission, automatic manual transmission (AMT), dual clutch transmission (DCT), etc. It can be targeted for transmissions or transfers to be performed. The drive system (FF, FR, MR, RR, 4WD, etc.) of the target vehicle is also not particularly limited.

The torque load member that is the object of the present invention is not limited to the rotary shaft constituting the power train of the automobile, for example, the rotary shaft of the wind turbine (main shaft, the rotary shaft of the speed increaser), the roll neck of the rolling mill, and the railway vehicle. Rotating shafts of various mechanical devices such as rotating shafts (axles, rotating shafts of speed reducers), rotating shafts of machine tools (main shafts, rotating shafts of feed systems), rotating shafts of construction machinery, agricultural machinery, household electric appliances, motors, etc. Etc. can be adopted.

When implementing the torque measuring device of the present invention, the torque sensor may be supported not only by a rolling bearing but also by another member such as a housing.

In the case of implementing the torque measuring device of the present invention, when the configuration in which the torque sensor is supported by the rolling bearing is adopted, the rolling bearing is not limited to the needle bearing, but also a ball bearing, a roller bearing, and a tapered roller bearing. Other types of rolling bearings such as may be used.

1 Rotating shaft 2 Rolling bearing 3 Torque sensor 4 Inner ring track 5 Detected surface 6 Outer ring 7 Needle 8 Cage 9 Inward flange 10 Outer ring track 11 Sensor holder 12 Fitting cylinder 13 Back yoke 14 Detection 15 First coil layer 16 2nd coil layer 17 3rd coil layer 18 4th coil layer 19 1st detection coil 20 2nd detection coil 21 3rd detection coil 22 4th detection coil 23 Bridge circuit 24 Oscillator 25 Lock-in amplifier 26 Shot pinning processing unit 27 Shot Peaning non-processing part

Claims (6)

A torque load member having a rotation center axis and an annular detected surface centered on the rotation center axis,
A magnetostrictive torque sensor having a coil facing the surface to be detected is provided.
The surface to be detected has shot peening processing units only at one or a plurality of locations in the circumferential direction.
The coil is arranged only in a partial circumferential range centered on the rotation center axis.
Torque measuring device. The shot peening processing units are arranged at a plurality of locations at equal intervals in the circumferential direction.
The torque measuring device according to claim 1. On the surface to be detected, the shot peening processing unit exists in a circumferential direction range of 30% or more with respect to the entire circumference.
The torque measuring device according to claim 1 or 2. Further provided with a rolling bearing that rotatably supports the torque load member,
The torque sensor is supported by the rolling bearing,
The torque measuring device according to any one of claims 1 to 3. Manufacture of a torque load member having a rotation center axis and an annular detected surface centered on the rotation center axis, and the detected surface has shot peening processing portions only at one or a plurality of locations in the circumferential direction. It ’s a method,
In the intermediate material of the torque load member, in the portion where the surface to be detected is to be formed, the shot peening process is performed with only one or a plurality of locations in the circumferential direction exposed and the remaining portions masked. A step of forming the shot peening processing unit only at the one or a plurality of locations is provided.
Manufacturing method of torque load member. Manufacture of a torque load member having a rotation center axis and an annular detected surface centered on the rotation center axis, and the detected surface has shot peening processing portions only at one or a plurality of locations in the circumferential direction. It ’s a method,
In the intermediate material of the torque load member, the portion where the surface to be detected is to be formed is subjected to shot peening treatment as a whole, and then the surface layer portion is removed from one or a plurality of locations in the circumferential direction. A step of using only the one or a plurality of locations as the shot peening processing unit is provided.
Manufacturing method of torque load member.

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