JP2010230348A - Work hardness measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a work hardness measuring instrument capable of measuring specific location of a work, such as a gear. <P>SOLUTION: The work hardness measuring instrument 10 is constituted of: a rotary mechanism 16, provided on a base plate 13 and equipped with the rotary shaft 15 rotated around the axis of the work 14; a work support mechanism 17 provided on the rotary shaft 15 to support the work 14; a sensor part 18 provided so as to face the work 14 supported by the work support mechanism 17 to detect the hardness in the vicinity of the surface of the work 14; a displaying and recording part 22 for displaying and recording the data detected by the sensor part 18; and a sensor advancing and retracting mechanism 24 for advancing and retracting the sensor part 18, provided to the base plate 13 with respect to the work 14. Since the work is rotated and makes the sensor part advance for it to be allowed to approach a measurement location, the hardness of the specific location of the work can be measured. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hardness measuring device that measures the hardness near the surface of a workpiece.

  2. Description of the Related Art Conventionally, a technique for measuring the hardness in the vicinity of the surface of a workpiece subjected to surface treatment in a nondestructive manner (see, for example, Patent Document 1 (FIGS. 2 and 3)).

The technique of patent document 1 is demonstrated below based on drawing.
As shown in FIG. 12A, an excitation coil 102 and a detection coil 103 are disposed adjacent to a cylindrical workpiece 101 that has been subjected to surface treatment. Next, an AC voltage (excitation voltage) is applied from the AC power source 104 to the excitation coil 102. Then, an eddy current is generated on the surface layer of the cylindrical workpiece 101. This eddy current generates an alternating current in the detection coil 103. The voltage (detection voltage) of the generated alternating current is measured by the measuring device 105. The correlation between the excitation voltage and the detection voltage will be described with reference to (c).

(C) is a graph in which the horizontal axis is the time axis and the vertical axis is the voltage. When the sine wave V1 is an excitation voltage curve, the detected voltage is represented by the sine wave V2. The phase difference between the sine wave V1 and the sine wave V2 is defined as Φ.
In (b), the X value represented by cosΦ has a good correlation with the carburization depth, and the Y value represented by sinΦ has a good correlation with the surface hardness.

  As the carburization depth and surface hardness change, the size of Φ and the height of V2 change. Therefore, by determining cosΦ and sinΦ by measurement, the carburization depth and surface hardness at that time can be specified.

Incidentally, a gear that is one of the mechanical elements is required to have high strength. As a technique for increasing the strength, a carburizing method is widely adopted. In the gear, the hardness in the vicinity of the surface is important, and it is necessary to measure the hardness of an important part of the gear, for example, the bottom of the gear, and it is particularly convenient if the total tooth bottom of the gear can be measured.
However, although the principle of measuring the outer peripheral surface of the cylindrical workpiece 101 is disclosed in Patent Document 1, it does not have a specific configuration for measuring a specific part of the workpiece such as a tooth bottom of a gear. That is, there is a need for a workpiece hardness measuring device that can measure a specific part of a workpiece such as a gear.

JP 2004-108873 A

  This invention makes it a subject to provide the workpiece hardness measuring apparatus which can measure the specific location of workpiece | works, such as a gearwheel.

  According to a first aspect of the present invention, there is provided a rotating mechanism provided on a base plate and provided with a rotating shaft that rotates around a workpiece axis, a workpiece supporting mechanism that is provided on the rotating shaft and supports the workpiece, and the workpiece supporting mechanism. A sensor unit that is provided so as to face a supported workpiece, detects the hardness near the surface of the workpiece, a display recording unit that displays and records information detected by the sensor unit, and a sensor unit that is provided on the base plate. And a sensor advance / retreat mechanism for advancing / retreating the workpiece.

  In the invention according to claim 2, the sensor unit includes a substantially U-shaped iron core facing the workpiece, a detection coil support provided on the iron core, extending toward the workpiece, and having a wedge-shaped cross-section at the tip. It is characterized by comprising a detection coil provided at the tip of this detection coil support for detecting a change in magnetic field due to eddy current generated in the work, and an excitation coil provided on the iron core for exciting the work.

  The invention according to claim 3 is characterized in that the workpiece is a helical gear.

  The invention according to claim 4 is characterized in that a sensor rotation mechanism that rotates about an axis orthogonal to the axis of the workpiece is interposed between the sensor portion and the sensor advance / retreat mechanism.

  According to a fifth aspect of the present invention, the rotation mechanism is provided via two slide mechanisms including a first slide mechanism that moves the workpiece along the workpiece axis and a second slide mechanism that moves the workpiece toward the sensor unit. It is provided on the base plate.

  The invention according to claim 6 is characterized in that the base plate is supported on the floor, and the second slide mechanism is provided on the floor via a shock absorber that absorbs an impact in the vertical direction.

  The invention according to claim 7 is characterized in that the first slide mechanism is provided with a scale for displaying height in the vertical direction and an indicating member pointing to the scale.

  The invention according to claim 8 is characterized in that the work has a through hole, and the work support mechanism includes a plurality of clamp claws that support the work by pressing the peripheral surface of the through hole.

  The invention according to claim 9 is characterized in that a plurality of sensor portions are formed.

  In the invention according to claim 1, the workpiece hardness measuring device includes a rotation mechanism provided with a rotation shaft, a workpiece support mechanism provided on the rotation shaft for supporting the workpiece, and a sensor unit for detecting hardness in the vicinity of the surface of the workpiece. And a sensor advance / retreat mechanism for advancing / retreating the sensor unit to / from the workpiece. Since the workpiece is rotated and the sensor unit is advanced to approach the measurement location, the hardness of the specific location of the workpiece can be measured.

In the invention according to claim 2, the sensor unit includes a substantially U-shaped iron core facing the workpiece, a detection coil support whose tip has a wedge-shaped cross-section, and a workpiece provided at the tip of the detection coil support. The detection coil includes a detection coil that detects a change in magnetic field due to the generated eddy current, and an excitation coil that is provided on the iron core and excites the workpiece. Since the excitation coil and the detection coil are integrated via the iron core, the measuring device can be miniaturized.
In addition, since the detection coil support having a wedge-shaped cross section penetrates to the vicinity of the tooth bottom of the gear, the hardness of the tooth bottom can be measured.

  In the invention which concerns on Claim 3, a workpiece | work is a helical gear. Although it is said that it is difficult to measure the hardness of a helical gear, according to the present invention, the hardness of a helical gear can be measured by nondestructive inspection.

In a fourth aspect of the invention, a sensor rotation mechanism that rotates about an axis orthogonal to the workpiece axis is interposed between the sensor unit and the sensor advance / retreat mechanism. Even if the measurement location is tilted around the axis perpendicular to the workpiece axis, the sensor unit is rotated in accordance with this tilt, so the sensor unit must be brought close to the measurement location and measurements can be taken to obtain accurate measurement values. Can do.
In addition, even if the workpiece is a helical gear, the sensor unit is rotated in accordance with the inclination of the tooth trace, so that the sensor unit can be reliably moved close to the tooth bottom to obtain an accurate measurement value. it can.

In the invention which concerns on Claim 5, the rotation mechanism is provided in the baseplate via the 1st slide mechanism which moves a workpiece | work along the axis | shaft of a workpiece | work, and the 2nd slide mechanism which moves a workpiece | work toward a sensor part. . Since the workpiece can be moved with reference to the sensor unit, it is possible to measure even workpieces of different sizes.
In addition, when the workpiece is a gear, the position is adjusted in accordance with the respective tooth width and gear diameter, so even gears of different sizes can be measured.

  In the invention which concerns on Claim 6, the 2nd slide mechanism is provided in the floor via the shock absorber which absorbs the impact of an up-down direction. For example, when the lock of the second slide mechanism is released, the second slide mechanism may be rapidly lowered by its own weight. In this case, if the shock is absorbed by the shock absorber, the lowering operation can be eased.

  In the invention which concerns on Claim 7, the scale for a height display in the up-down direction and the indicating member which points to this scale are provided in the 1st slide mechanism. By aligning the scales, manual position adjustment of the workpiece can be performed accurately and easily.

  In the invention which concerns on Claim 8, a workpiece | work has a through-hole and the workpiece | work support mechanism is provided with the some clamp nail | claw which supports a workpiece | work by pushing the surrounding surface of a through-hole. Since the inside of the workpiece is supported, measurement outside the workpiece can be performed quickly.

  In the invention which concerns on Claim 9, the sensor part is comprised with two or more. Since a plurality of workpieces are measured in one operation, the inspection efficiency can be improved.

It is a block diagram of the workpiece hardness measuring apparatus which concerns on this invention. FIG. 2 is a view taken in the direction of arrow 2 in FIG. 1. FIG. 3 is a sectional view taken along line 3-3 in FIG. 2. It is a figure explaining a shock absorber. It is a figure explaining a workpiece support mechanism. It is a figure explaining a sensor rotation mechanism. It is an enlarged view of a sensor part. FIG. 8 is a sectional view taken along line 8 in FIG. 7. FIG. 9 is a sectional view taken along line 9 of FIG. 7. It is operation | movement explanatory drawing of a workpiece hardness measuring apparatus. It is a block diagram of the workpiece hardness measuring apparatus which concerns on another Example of this invention. It is a figure explaining the basic principle of the prior art.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

First, Embodiment 1 of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the workpiece hardness measuring apparatus 10 includes a floor 11, a base plate 13 supported on the floor 11 via an insulating rubber 12, and a shaft 14 provided on the base plate 13 and rotated around the axis of the workpiece 14. A rotating mechanism 16 having a rotating shaft 15, a workpiece supporting mechanism 17 provided on the rotating shaft 15 for supporting the workpiece 14, and a workpiece 14 provided to face the workpiece 14 supported by the workpiece supporting mechanism 17. A sensor unit 18 that detects the hardness in the vicinity of the surface; a hardness conversion unit 21 that acquires information detected by the sensor unit 18 and converts it into hardness; a display recording unit 22 that displays and records the converted information; A sensor advance / retreat mechanism 24 is provided on the base plate 13 via an L-shaped support member 23 and advances / retreats the sensor unit 18 with respect to the work 14.

  As shown in FIG. 2, two slide mechanisms including a first slide mechanism 25 that moves the workpiece 14 along the axis of the workpiece 14 and a second slide mechanism 26 that moves the workpiece 14 toward the sensor unit 18. A rotation mechanism 16 is provided on the base plate 13 via the.

  The first slide mechanism 25 is slidably provided on the vertical plate 27 provided on the base plate 13, the two vertical rails 28 and 28 provided on the vertical plate 27, and the vertical rails 28 and 28. Vertical sliders 29 and 29, and a vertical movement plate 31 provided on the vertical sliders 29 and 29-.

  The second slide mechanism 26 is slidable on the horizontal plate 32 provided on the vertical movement plate 31, the two horizontal rails 33, 33 provided on the horizontal plate 32, and the horizontal rails 33, 33. It comprises horizontal sliders 34 and 34 provided, and a horizontal movement plate 35 provided on these horizontal sliders 34 and 34.

Returning to FIG. 1, the second slide mechanism 26 is provided on the floor 11 via a shock absorber 36 that absorbs a vertical impact.
A sensor rotating mechanism 41 that rotates about an axis orthogonal to the axis of the workpiece 14 is interposed between the sensor unit 18 and the sensor advance / retreat mechanism 24. A fixed member 43 is provided on the advance / retreat slider 42 of the sensor advance / retreat mechanism 24, and a sensor rotation mechanism 41 is provided on the fixed member 43.

  Reference numeral 44 denotes an AC power source. An exciting coil (detailed later) is applied by an AC power supply 44. Reference numeral 45 denotes a control unit that controls the rotation mechanism 16, the work support mechanism 17, and the sensor advance / retreat mechanism 24.

  Returning to FIG. 2, a scale 46 for height display is provided in the vertical direction on the base plate 13 to which the vertical plate 27 of the first slide mechanism 25 is fixed. An indication member 47 that points to the scale 46 is provided on the horizontal plate 32.

  The second slider 26 is provided with a lateral lock lever 48 that locks the movement of the lateral movement plate 35. A rotation mechanism 16 is provided on the lateral movement plate 35 via bolts 49.

As shown in FIG. 3, the first slide mechanism 25 includes support plates 51, 51 provided on the vertical plate 27, a handle support member 52 provided on the upper ends of the support plates 51, 51, A handle 53 rotatably supported by the handle support member, a long screw 54 connected to the handle 53, a nut portion 55 provided on the longitudinal movement plate 31 and meshing with the long screw 54, and the handle 53 A handle lock lever 56 for locking is provided.
By opening the handle lock lever 56, the handle 53 can be turned to move the vertical movement plate 31 up and down. By closing the handle lock lever 56, the bundle 53 can be locked and the longitudinally moving plate 31 can be fixed.

  As shown in FIG. 4, the shock absorber 36 includes a fixed plate 58 fixed to the lateral plate 32 via bolts 57, 57, and a swinging member 61 provided on the upper portion of the fixed plate 58, A rod 62 connected to the swinging member 61, a piston 63 connected to the rod 62, a hole 64 provided in the piston 63, and the piston 63 fixed to the floor 11 via a bolt 65. It comprises a cylinder 66 that is slidably housed, and an oil 67 in the cylinder 66.

  The shock absorber 36 is not limited to the above-described configuration, and cannot support the vertical movement of the work (FIG. 1, reference numeral 14) by supporting the second slide mechanism (FIG. 1, reference numeral 26) and the like, such as a structure supported by a compression spring. Other configurations may be used as long as they are implemented without any problems.

  As shown in FIG. 5A, the gear 14 as a work has a through hole 68. The work support mechanism 17 includes a housing 71, rails 72, 72 provided inside the housing 71, and is slidably provided on these rails 72, 72, and presses the peripheral surface of the through hole 68 to rotate the gear 14. A plurality of clamp claws 73, 73 to be supported, compression springs 74, 74 provided on the housing 71 urging the clamp claws 73, 73 toward the inside of the housing 71, and rising inside the clamp claws 73, 73. It comprises a cone 75 that pushes the clamp pawls 73 and 73 and an elevating cylinder 76 that moves the cone 75 up and down.

(B) is the bb sectional view taken on the line (a), and three clamp claws 73 are provided. The gear 14 can be reliably supported by the three clamp claws 73.
Note that the number of the clamp claws 73 is not limited to three, and an appropriate number of clamp claws 73 may be provided according to the workpiece 14 such as four. Moreover, the workpiece | work support mechanism 17 is not limited to the above-mentioned structure, If the workpiece | work 14 can be supported by pushing the surrounding surface of the through-hole 68, another common clamp mechanism may be used.

As shown in FIG. 6, the work 14 is a helical car.
The sensor rotation mechanism 41 is provided with an angle scale 77 that can know the rotation angle. The sensor rotation mechanism 41 is rotated as indicated by an arrow (1) in accordance with the inclination of the tooth trace of the helical wheel 14 to set the angle. It can be done easily.
An impact absorbing mechanism 78 is provided between the sensor unit 18 and the sensor rotation mechanism 41 to absorb an impact when the sensor unit 18 contacts the helical gear 14.

As shown in FIG. 7, the sensor unit 18 includes a folder 81 provided at the tip of the shock absorbing mechanism (FIG. 6, reference numeral 78), and a substantially square attached to the folder 81 with bolts 82 and 82. A character-shaped iron core 83, a detection coil support 85 provided on the iron core 83, extending toward the gear 14 as a workpiece and slidably fixed by screws 84, and provided at the tip of the detection coil support 85 A detection coil 86 for detecting a change in magnetic field due to an eddy current generated in the gear 14, an excitation coil 87 provided on the iron core 83 for exciting the gear 14, and a steel provided at the tip of the iron core 83 and in contact with the tooth surface of the gear 14. It consists of spheres 88 and 89.

  As shown in FIG. 8, the detection coil 86 is supported by the detection coil support 85 via a resin body 91 such as nylon having a wedge-shaped cross section having a high insulating property. Since the resin body 91 has a wedge-shaped cross-sectional shape, the detection coil 86 can be brought close to the tooth bottom 92 of the gear 14.

  As shown in FIG. 9, the ball diameter of the steel ball 88 is set to an outer diameter that passes between the adjacent tooth tips 93 and the tooth tips 93 but touches the tooth surface before reaching the tooth bottom 92. That is, since the contact points 94 and 94 are in contact, the positions of the steel balls 88 in the left-right direction and the up-down direction are defined. In addition, the center of the steel ball 88 matches the center of the tooth bottom 92. As a result, the distance of the detection coil (FIG. 8, reference numeral 86) from the tooth bottom 92 and the distance of the excitation coils 87, 87 can be made constant. As a result, measurement reliability can be increased.

The operation of the workpiece hardness measuring apparatus described above will be described next.
In FIG. 10, as shown to (a), the detection coil 86 is advanced to the gear 14 as a workpiece | work in a stationary state like the arrow (2). As shown in (b), an arbitrary tooth bottom 92 is made to face the detection coil 86, and the hardness of the tooth bottom 92 is measured. When finished, the detection coil 86 is moved backward as indicated by the arrow (3).

  Next, as shown in (c), the gear 14 is turned by one pitch (one tooth) (arrow (4)). Then, as shown in (d), the adjacent tooth bottom 92 faces the detection coil 86. Thereafter, the process returns to (a) and continues.

Next, a second embodiment of the present invention will be described with reference to the drawings.
In FIG. 11, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.
In the workpiece hardness measuring apparatus 10, a plurality of sensor units 18 are configured.

  The workpiece support mechanism 17 includes a base jig 95 that is provided on the rotary shaft 15 and supports the lower workpiece 14, an intermediate jig 96 that is provided on the lower workpiece 14 and supports the upper workpiece 14, and an upper workpiece. 14 and a holding jig 98 that holds the workpieces 14 and 14 through bolts 97 from above.

The operation of the workpiece hardness measuring apparatus of the second embodiment described above will be described next.
The two workpieces 14 and 14 are set on the workpiece support mechanism 17, and the two workpieces 14 and 14 are simultaneously measured by the two sensor units 18 and 18.
As a result, the measurement time per work can be shortened, and work efficiency can be improved.

  Although the workpiece hardness measuring device of the present invention is applied to a gear in the embodiment, it can also be applied to a shaft and can be applied to general machine parts as long as it is a surface-treated member. Absent.

  The workpiece hardness measuring device of the present invention is suitable for a gear.

  DESCRIPTION OF SYMBOLS 10 ... Work hardness measuring apparatus, 11 ... Floor, 13 ... Base plate, 14 ... Workpiece (gear, helical gear), 15 ... Rotating shaft, 16 ... Rotation mechanism, 17 ... Work support mechanism, 18 ... Sensor part, 22 ... Display recording unit, 24 ... sensor advance / retreat mechanism, 25 ... first slide mechanism, 26 ... second slide mechanism, 36 ... shock absorber, 41 ... sensor rotation mechanism, 46 ... scale, 47 ... indicating member, 63 ... through hole, 73 ... Clamp claw, 83 ... Iron core, 85 ... Detection coil support, 86 ... Detection coil, 87 ... Excitation coil.

Claims (9)

A rotation mechanism provided on the base plate and provided with a rotation shaft that rotates around the workpiece axis;
A workpiece support mechanism provided on the rotating shaft and supporting the workpiece;
A sensor unit that is provided to face the workpiece supported by the workpiece support mechanism and detects the hardness in the vicinity of the surface of the workpiece;
A display recording unit for displaying and recording information detected by the sensor unit;
A workpiece hardness measuring apparatus, comprising: a sensor advance / retreat mechanism provided on the base plate for advancing / retreating the sensor portion with respect to the workpiece. The sensor unit is a substantially U-shaped iron core facing the workpiece;
A detection coil support provided on the iron core, extending toward the workpiece and having a wedge-shaped cross-section at the tip;
A detection coil provided at the tip of the detection coil support for detecting a change in magnetic field due to an eddy current generated in the workpiece;
The work hardness measuring apparatus according to claim 1, further comprising an exciting coil provided on the iron core and exciting the work.   The workpiece hardness measuring apparatus according to claim 2, wherein the workpiece is a helical gear.   2. The workpiece hardness measuring apparatus according to claim 1, wherein a sensor rotation mechanism that rotates about an axis orthogonal to the axis of the workpiece is interposed between the sensor unit and the sensor advance / retreat mechanism.   The rotation mechanism is attached to the base plate via two slide mechanisms including a first slide mechanism that moves the workpiece along the axis of the workpiece and a second slide mechanism that moves the workpiece toward the sensor unit. The workpiece hardness measuring device according to claim 1, wherein the workpiece hardness measuring device is provided.   6. The workpiece hardness measuring apparatus according to claim 5, wherein the base plate is supported by a floor, and the second slide mechanism is provided via a shock absorber that absorbs an impact in the vertical direction on the floor. .   The workpiece hardness measuring apparatus according to claim 5 or 6, wherein a scale for displaying height in the vertical direction and an indicating member pointing to the scale are provided on the first slide mechanism.   The workpiece hardness according to claim 1, wherein the workpiece has a through hole, and the workpiece support mechanism includes a plurality of clamp claws that support the workpiece by pressing a peripheral surface of the through hole. Measuring device.   The workpiece hardness measuring apparatus according to claim 1, wherein the sensor unit includes a plurality of sensors.

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