WO2011158330A1 - Structure for welding ring gear and differential case - Google Patents

Structure for welding ring gear and differential case Download PDF

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Publication number
WO2011158330A1
WO2011158330A1 PCT/JP2010/060128 JP2010060128W WO2011158330A1 WO 2011158330 A1 WO2011158330 A1 WO 2011158330A1 JP 2010060128 W JP2010060128 W JP 2010060128W WO 2011158330 A1 WO2011158330 A1 WO 2011158330A1
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WO
WIPO (PCT)
Prior art keywords
welded
differential case
gap
probe
weld metal
Prior art date
Application number
PCT/JP2010/060128
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French (fr)
Japanese (ja)
Inventor
雅大 藤本
内田　圭亮
信吾 岩谷
隆人 遠藤
剛 倉本
浩一 恒川
賢 遠藤
Original Assignee
トヨタ自動車株式会社
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Publication date
Application filed by トヨタ自動車株式会社 filed Critical トヨタ自動車株式会社
Priority to PCT/JP2010/060128 priority Critical patent/WO2011158330A1/en
Publication of WO2011158330A1 publication Critical patent/WO2011158330A1/en

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/041—Analysing solids on the surface of the material, e.g. using Lamb, Rayleigh or shear waves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H48/00—Differential gearings
    • F16H48/38—Constructional details
    • F16H48/40—Constructional details characterised by features of the rotating cases
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/07—Analysing solids by measuring propagation velocity or propagation time of acoustic waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G01N29/11—Analysing solids by measuring attenuation of acoustic waves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H48/00—Differential gearings
    • F16H48/38—Constructional details
    • F16H2048/382—Methods for manufacturing differential gearings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H48/00—Differential gearings
    • F16H48/38—Constructional details
    • F16H2048/385—Constructional details of the ring or crown gear
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/04—Wave modes and trajectories
    • G01N2291/044—Internal reflections (echoes), e.g. on walls or defects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/26—Scanned objects
    • G01N2291/267—Welds

Definitions

  • the present invention relates to a welded structure of a ring gear and a differential case.
  • a differential gear used for a driving mechanism of an automobile is one of differential devices that are used for a shaft that connects driving wheels of an automobile and absorbs a speed difference between an inner ring and an outer ring when the automobile turns a curve.
  • FIG. 22 is a cross-sectional view of the differential gear 110 described in Patent Document 1.
  • the differential gear 110 is provided in a ring gear 102 that is held outside the differential case 101, a space 103 in which the differential case 101 is assembled, and a pinion gear 105 that is attached to the differential case 101 via a pinion shaft 104, and meshes with the pinion gear 105.
  • a connecting gear 107 attached to the axle 106 is also included.
  • the driving force generated by the automobile engine or the like is transmitted from the driving force transmission gear 108 to the ring gear 102 joined to the differential case 101, and the differential case 101 and the ring gear 102 rotate integrally.
  • the pinion gear 105 rotates in accordance with the rotation of the differential case 101 and transmits a driving force to the axle 106 via the connecting gear 107.
  • FIG. 23 is a schematic cross-sectional view showing a conventional welding structure 100.
  • the abutting surface 102a of the ring gear 102 is press-fitted into the abutting surface 101a of the differential case 101, and welding wires (not shown) are melted on the upper and lower sides of the abutting surfaces 101a and 102a in pressure contact.
  • the ring gear 102 and the differential case 101 are welded and joined by pouring the welding metal 109.
  • the differential case 101 needs to rotate without shaking after being attached to the automobile. This is because the shake of the differential case 101 affects the quietness and vibration of the automobile, the life of the differential gear, and the like.
  • the welding strength of the butted surface 102a of the ring gear 102 and the butted surface 101a of the differential case 101 is necessary to secure to be higher than the design value.
  • the leg lengths D111 and D112 of the welded portions 111 and 112 of the differential gear 110 are diffracted waves generated by reflection of the ultrasonic wave transmitted by the probe 121 to the end 109a of the weld metal 109, as shown in FIG. (Refer to the one-dot chain line in the figure) is received by the probe 121, and the boundary between the gap S11 formed between the butted surfaces 101a and 102a and the end 109a of the weld metal 109 is detected and inspected. It was.
  • the leg lengths D111 and D112 of the welded portions 111 and 112 can be measured nondestructively.
  • the leg lengths D111 and D112 of the welded portions 111 and 112 cannot be accurately measured.
  • the probe 121 is arranged in one direction with respect to the differential case 101, and the ultrasonic wave transmitted from the probe 121 is reflected on the terminal end 109a of the weld metal 109 to be one point in the figure.
  • the leg lengths D111 and D112 are inspected by generating a diffracted wave indicated by a chain line and causing the probe 121 to receive the diffracted wave.
  • the minimum size that can be detected by the probe 121 is about the same as the wavelength of the ultrasonic wave transmitted from the probe 121. Therefore, in order to detect the boundary between the terminal end 109a of the weld metal 109 and the gap S11, the width W of the gap S11 needs to be at least as large as the wavelength of the ultrasonic wave. However, in the conventional welded structure 100, since the gap S11 is formed between the flat butted surface 101a and the flat butted surface 102a, the width W of the gap S11 is only a few ⁇ m. It was much shorter than the wavelength of the ultrasonic wave transmitted from 121 (for example, 0.30 mm).
  • FIG. 24 is an image diagram of a conventional leg length inspection.
  • the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a ring gear and differential case welding structure in which the length of the welded portion of the ring gear and differential case is accurately inspected.
  • a welding structure is such that the first butted surface of the differential case and the second butted surface of the ring gear are abutted, and the end of the abutted portion is welded by a weld metal.
  • the welding structure in which the welded portion welded with the weld metal is irradiated with ultrasonic waves and the length of the welded portion is inspected by analyzing an echo reflected from a reflection source, the first abutting surface And a gap having a width larger than the wavelength of the ultrasonic wave, and the gap is formed on at least one of the first abutting surface and the second abutting surface. The end of the weld metal is exposed in the gap.
  • the first and second butting surfaces are provided in an annular shape
  • the welding portion includes a first welding portion welded from one end of the first and second butting surfaces, and the first 1 and a second welded portion welded from the other end of the second butting surface, and the first and second welded portions are preferably exposed in the gap.
  • a concave groove is formed in at least one of the first butted surface of the differential case or the second butted surface of the ring gear, and a gap is provided between the first butted surface and the second butted surface. It has been. Since the width of the gap is larger than the wavelength of the ultrasonic wave, when the ultrasonic wave is transmitted and reflected at the end of the weld metal exposed in the gap, the reflected wave is dispersed into the gap and reflected to other parts. Is generated. Therefore, by analyzing the reflected wave of the ultrasonic wave, the boundary between the end of the weld metal and the gap can be detected, and the length of the welded portion can be measured. Therefore, according to the welding structure of the said aspect, the length of a welding part is test
  • the weld structure having the above-described configuration is formed by abutting a first butting surface and a second butting surface provided in an annular shape, and welding is performed from one end of the first and second butting surfaces to form a first welding portion. Welding is performed from the other end of the second butting surface to form a second welded portion. The first and second welded portions are exposed in the gap. Therefore, according to the welding structure having the above-described configuration, the ultrasonic waves are transmitted to the first and second welded portions, and the reflected waves are analyzed, whereby the terminal end of the weld metal forming the first and second welded portions is analyzed. Each position is inspected with high accuracy.
  • FIG. 1 It is an image figure which shows the external appearance of the differential gear which concerns on 1st Embodiment of this invention and applied the welding structure. It is a fragmentary sectional view of the ring gear and differential case before welding. It is the A section expanded sectional view of FIG. It is a schematic block diagram of an ultrasonic flaw detection system. It is a figure which shows the image which test
  • FIG. 2 is a cross-sectional view of a differential gear described in Patent Document 1.
  • FIG. It is a schematic sectional drawing which shows the conventional welding structure. It is an image figure of the conventional leg length test
  • FIG. 1 is an image diagram showing an appearance of a differential gear 4 to which a welded structure 10 of a ring gear 2 and a differential case 1 is applied according to the first embodiment of the present invention.
  • FIG. 2 is a partial cross-sectional view of the ring gear 2 and the differential case 1 before being welded.
  • FIG. 3 is an enlarged cross-sectional view of a portion A in FIG.
  • the differential gear 4 shown in FIG. 1 is used for an automobile as in the prior art. As shown in FIG. 2, the differential gear 4 press-fits the butting surface 2a of the ring gear 2 into the butting surface 1a of the differential case 1, and then, as shown in FIG.
  • the butting surfaces 1a and 2a are placed on the surface side of the differential gear 4 (see FIG.
  • the welding structure 10 welded from the middle upper side and the back side (lower side in the figure) is applied.
  • the welded structure 10 includes a butt surface 2a of the ring gear 2 and a butt surface 1a of the differential case 1.
  • a gap S1 having a width B larger than the wavelength of the ultrasonic wave is provided therebetween.
  • the ring gear 2 is made of a metal such as cast iron.
  • the ring gear 2 is formed in a substantially cylindrical shape.
  • a gear portion 2 b meshed with the driving force transmission gear 108 (see FIG. 22) is formed on the outer peripheral surface of the ring gear 2 so as to be coaxial with the ring gear 2.
  • an annular butting surface 2 a is formed coaxially with the ring gear 2 on the inner peripheral surface of the ring gear 2.
  • the butting surface 2a is formed by a flat surface parallel to the vertical axis of the ring gear 2 in the drawing.
  • the differential case 1 is made of a metal such as cast iron.
  • the differential case 1 is formed in a substantially cylindrical shape.
  • a butt surface 1 a is formed in an annular shape on the outer peripheral surface of one end of the differential case 1.
  • the abutting surface 1 a is formed coaxially with the differential case 1.
  • the abutting surface 1a is formed by a flat surface parallel to the vertical axis of the differential case 1 in the drawing.
  • the abutting surface 1a has an outer diameter dimension X1 larger than the inner diameter dimension X2 of the abutting surface 2a, and is provided with a press-fitting allowance for press-fitting the abutting surface 2a into the abutting surface 1a.
  • the concave groove 1b is formed in an annular shape along the central portion of the abutting surface 1a.
  • the differential case 1 and the ring gear 2 are coaxially positioned by press-fitting the butted surface 2 a of the ring gear 2 into the butted surface 1 a of the differential case 1.
  • the butted surfaces 1a and 2a to be pressed are melted by applying heat to the upper side (surface side) in the figure, and a weld metal 5 in which a welding wire (not shown) is melted is melted into the melted portion.
  • a welding wire not shown
  • the butted surfaces 1a and 2a are welded to the welding metal 6 by a predetermined length (leg length) D2 from the lower side (back side) in the figure to form a welded portion 8.
  • leg length the rotational torque transmitted from the driving force transmission gear 108 (see FIG. 22) to the ring gear 2 acts on the press-fitted portions of the butted surfaces 1a and 2a and the welded portions 7 and 8.
  • the leg lengths D1 and D2 of the weld metals 5 and 6 are set so as to ensure durability against the rotational torque.
  • a gap S1 is formed in an annular shape between the butted surfaces 1a and 2a that are welded in this way, due to the concave groove 1b.
  • the width B of the gap S1 that is, the radial dimension (horizontal direction in the figure) of the differential case 1 from the butted surface 1a of the groove 1b is the minimum detection size that can be detected by the ultrasonic flaw detection system 11 (probe 14). It is set larger.
  • the width B of the gap S1 is set to a size of 95% or more with respect to the wavelength of the ultrasonic wave (ultrasonic wave transmitted from the probe 14) used in the ultrasonic flaw detection system 11. It is preferable to set it to the same level as the wavelength.
  • the ultrasonic wave transmitted from the probe 14 has a wavelength of 0.31 mm when the frequency is 10 MHz and the sound velocity is 3080 m / s.
  • the width B of the gap S1 is set to 0.30 mm or more.
  • the axial length C of the gap S1 that is, the groove width C in the axial direction (vertical direction in the figure) of the differential groove 1b is determined by the design position of the terminal end 5a of the weld metal 5 and the weld metal 6 It is set so as to be wider than the distance from the design position of the end 6a.
  • the melted weld metals 5 and 6 may contain air or dust.
  • a gap S1 is formed between the butted surfaces 1a and 2a, and the welded portions 7 and 8 are so exposed that the terminal ends 5a and 6a of the weld metals 5 and 6 are exposed in the gap S1. Is formed. Therefore, the air, dust, etc. contained in the weld metals 5 and 6 float on the surface of the weld metals 5 and 6 exposed in the space S1 and hardly remain in the weld metals 5 and 6. Therefore, blowholes are not easily generated inside the weld metals 5 and 6.
  • the differential gear 4 can be applied even if the rotational torque transmitted from the driving force transmission gear 108 (see FIG. 22) acts on the press-fitted portions of the butted surfaces 1a and 2a and the welded portions 7 and 8. The stress is not concentrated on the blowhole generating portion, and the durability of the welded portions 7 and 8 is improved.
  • FIG. 4 is a schematic configuration diagram of the ultrasonic flaw detection system 11.
  • the differential gear 4 has many irregularities, and the welded portions 7 and 8 of the abutting surfaces 1 a and 2 a of the differential gear 4 have surplus deposits 5 and 6.
  • the oblique angle flaw detection method using is adopted.
  • the ultrasonic flaw detection system 11 of the present embodiment uses a Flex Scan System FLX-743G (model number) manufactured by SONIX as the system itself, and the water immersion type probe used is Olympus V311 10 MHz (model number). It is configured using M309 5MHz (model number) and a custom-made product (no model number).
  • the ultrasonic flaw detection system 11 mainly includes a water tank 12, a probe 14, a rotating device 15, a pulsar receiver 16, an AD / DA conversion board 17, and a personal computer 18.
  • the water tank 12 is filled with water 13.
  • the probe 14 is held in a state where it is immersed in the water tank 12, and has a built-in transducer for transmitting and receiving ultrasonic waves.
  • a phased array type probe that includes a plurality of transducers and can focus the ultrasonic waves and change the transmission direction of the ultrasonic waves by shifting the excitation timing of the plurality of transducers.
  • the rotating device 15 is arranged at the bottom of the water tank 12 to rotate the differential gear 4 that becomes an object to be inspected.
  • the pulsar receiver 16 is connected to the transducer of the probe 14 and outputs an electrical signal for controlling an ultrasonic wave transmitted from the probe 14 to the differential gear 4 to the transducer, while receiving an echo received by the transducer. It is input and converted into an electrical signal.
  • the AD / DA conversion board 17 mutually converts an analog signal and a digital signal.
  • the personal computer 18 is a known computer including an input device 18a, a display device 18b, and an internal storage device (not shown). Analysis software (not shown) is stored in an internal storage device (not shown). Analysis software (not shown) controls ultrasonic waves transmitted from the probe 14 using parameters input to the input device 18a, analyzes echoes received by the probe 14, and displays the analysis results on the display device 18b. indicate.
  • the tester submerges the differential gear 4 serving as an object to be inspected in water 13 stretched on the water tank 12 and places it on the rotating device 15.
  • analysis software not shown
  • an initial screen is displayed on the input device 18a.
  • the tester gives parameters necessary for the inspection (such as the material of the differential case 1 and the ring gear 2 and the sound velocity of the ultrasonic wave passing through the differential case 1 and the ring gear 2) and a start instruction for starting the leg length inspection of the welded portion 7.
  • the ultrasonic flaw detection system 11 starts the leg length inspection of the welded portion 7.
  • the personal computer 18 outputs a control signal for transmitting ultrasonic waves having a predetermined frequency, a predetermined band, and a predetermined wavelength from the probe 14.
  • the control signal is converted from a digital signal to an analog signal by the AD / DA conversion board 17 and transmitted from the pulsar receiver 16 to the transducer of the probe 14.
  • FIG. 5 is a diagram showing an image for inspecting the leg length D1 of the surface-side welded portion 7 of the differential gear 4.
  • the probe 14 emits ultrasonic waves at a predetermined frequency toward a predetermined range (hereinafter referred to as “first target position”) including a position where the end 5 a of the weld metal 5 exists by design. Send with.
  • first target position a predetermined range
  • the rotating device 15 rotates to rotate the differential gear 4 once. Thereby, the position where the ultrasonic wave is transmitted is shifted in the circumferential direction of the differential gear 4.
  • the ultrasonic wave transmitted from the probe 14 enters the differential case 1 of the differential gear 4 through the water 13.
  • the water 13 is interposed between the probe 14 and the differential case 1 to enhance the propagation efficiency of ultrasonic waves.
  • the ultrasonic waves are refracted when entering the surface of the differential case 1 from the water 13 and propagate in the differential case 1 toward the “first target position”.
  • the end 5a of the weld metal 5 is exposed in the gap S1.
  • the end 5a is solidified so as to flow out to the gap S1.
  • the ultrasonic wave transmitted toward the terminal end 5a propagates from the differential case 1 side to the ring gear 2 side through the gap S1, and generates a diffracted wave as shown by a one-dot chain line in FIG. Since the width of the gap S1 is set to be approximately the same as the wavelength of the ultrasonic wave, the generated diffracted wave is not easily attenuated by interference. Therefore, the diffracted wave generated by reflection at the terminal end 5 a is received by the probe 14.
  • the ultrasonic waves transmitted to the part of the weld metal 5 that contacts the differential case 1 and the abutting surface 2a that forms the gap S1 are reflected without going around the back side. The reflected wave is received by the probe 14.
  • the probe 14 transmits ultrasonic waves toward the “first target position”, a diffracted wave is generated in a predetermined range including a position where the end 5a of the weld metal 5 is designed.
  • the position where it occurs can be inspected. That is, even when the position of the terminal 5a is deviated from the designed position, the terminal 5a can be detected.
  • the probe 14 is held at a fixed position in the water tank 12, but the differential gear 4 is rotated once by the rotating device 15, and therefore, along the entire circumferential direction of the differential gear 4, The position and area where the diffracted wave is generated can be inspected.
  • the pulsar receiver 16 converts the diffracted wave or reflected wave received by the probe 14 into an electric signal and transmits it to the AD / DA conversion board 17.
  • the AD / DA conversion board 17 converts the received electrical signal from an analog signal to a digital signal and transmits it to the personal computer 18.
  • the personal computer 18 analyzes the electrical signal received from the AD / DA conversion board 17 and accumulates and stores the analysis result in an internal storage device (not shown). Then, the personal computer 18 displays the analysis result on the display device 18b for visualization.
  • the display device 18b includes at least an A scope (basic display: displays echo height on the time axis), a B scope (cross section display: displays the position of the probe 14 and the depth position of the terminal ends 5a and 6a), and the C scope.
  • a display screen based on plane display: surface display of terminations 5a and 6a) is displayed. Note that these display screens may be displayed together on one screen, or may be selectively displayed by a tester switching.
  • the personal computer 18 calculates the time from when the probe 14 transmits an ultrasonic wave until it receives a diffracted wave or a reflected wave from the electrical signal received from the AD / DA conversion board 17, and at the calculated time. Then, the propagation time of ultrasonic waves (distance from the probe 14 to the reflection source) is calculated by multiplying the speed (sound speed) of ultrasonic waves passing through the differential case 1. Then, the personal computer 18 displays an A scope in which the echo intensity (waveform) of the diffracted wave or the reflected wave and the propagation time (distance) of the ultrasonic wave are displayed on the rectangular coordinates on the display device 18b.
  • the A scope is easy to handle analysis data. However, in order to determine the positions of the ends 5a and 6a of the weld metals 5 and 6 and the defects and dimensions in the weld metals 5 and 6 from the waveform, skill of the tester is required.
  • the personal computer 18 luminance-modulates (or color-modulates) the A scope waveform and expresses it with a line, and the scanning position of the differential gear 4 of the probe 14 and the ultrasonic wave propagation time (depth (distance)) are expressed in rectangular coordinates.
  • the taken B scope is displayed on the display device 18b.
  • a diffracted wave has a characteristic that the rate of change in echo height is larger than that of a reflected wave. Therefore, the B scope display screen displays the luminance (color) at the position where the diffracted wave is generated different from the luminance (color) at the position where the reflected wave is generated.
  • the position of the terminal end 5a of the weld metal 5 where the diffracted wave is generated (the leg length D1 of the welded portion 7) is visualized from the echo height (luminance or color) displayed on the display screen of the B scope, and is intuitively viewed by the tester. Will be grasped.
  • the personal computer 18 creates a cross-sectional image based on the space between the butted surfaces 1a and 2a from the analysis result and displays it on the display device 18b. Therefore, from the cross-sectional image, the overall shape of the weld metal 5 and internal defects are visualized along the axial direction of the differential gear 4 and intuitively grasped by the tester.
  • the personal computer 18 performs luminance modulation (or color modulation) on the received echo intensity at a certain depth in the probe 14 and displays the C scope displayed at the position on the differential gear 4 on the display device 18b. Similar to the display screen of the B scope, the luminance (or color) at the position where the diffracted wave is generated is displayed on the C scope display screen so as to be different from the luminance (or color) at the position where the reflection occurs. . Therefore, the position (depth) of the terminal end 5a of the weld metal 5 and the range of scratches generated in the weld metal 5 are visualized. As a result, the tester can intuitively grasp the range of scratches generated in the weld metal 5 along the entire circumferential direction of the differential gear 4.
  • luminance modulation or color modulation
  • the leg length D1 of the welded portion 7 of the gear 2 and the differential case 1 is inspected with high accuracy.
  • the ultrasonic flaw detection system 11 performs the leg length inspection of the welded portion 8.
  • the leg length inspection of the welded portion 8 is basically performed on the same principle as the leg length inspection of the welded portion 7 described above. However, since the welded portion 8 is further away from the probe 14 than the welded portion 7, it is difficult for the probe 14 to receive the diffracted wave generated by the reflection from the terminal end 6 a of the weld metal 6.
  • the welded portion 8 is inspected for the leg length D2 using a reflected wave instead of a diffracted wave.
  • a reflected wave instead of a diffracted wave.
  • FIG. 6 is a view showing an image for inspecting the leg length D2 of the back surface side welded portion 8 of the differential gear 4.
  • the probe 14 transmits ultrasonic waves in a pulse shape toward a predetermined range (hereinafter referred to as “second target position”) including the designed position of the end 6 a of the weld metal 6.
  • the ultrasonic wave transmitted in this case is set to have a higher frequency and a shorter wavelength than when the welded part 7 is inspected for the leg length because the welded part 8 is farther from the probe 14 than the welded part 7. Is done.
  • the minimum detection size of the ultrasonic flaw detection system 11 (probe 14) is set smaller than when the leg length D1 of the welded portion 7 is inspected. Simultaneously with the transmission of the ultrasonic wave, the rotating device 15 is driven to rotate, and the differential gear 4 is rotated once in the water tank 12.
  • the end 6a of the weld metal 6 is exposed in the gap S1. Since the gap S1 is sealed with both ends closed by the welded portions 7 and 8, even if the differential gear 4 is submerged, an air layer with low ultrasonic propagation efficiency can be formed.
  • the width of the gap S1 is set larger than the wavelength of the ultrasonic wave. Even if an ultrasonic wave transmitted to the end 6a of the weld metal 6 wraps around the back side of the weld metal 6 via the gap S1 and generates a diffracted wave, the distance from the end 6a to the probe 14 is long and diffracted. The wave attenuates while returning from the differential case 1 toward the probe 14.
  • the reflected wave reflected at the terminal end 6a travels directly toward the probe 14 via the differential case 1, and therefore is less likely to attenuate than the diffracted wave.
  • the ultrasonic wave used for the inspection of the leg length D2 of the welded portion 8 has a higher frequency and a shorter wavelength than the ultrasonic wave used for the inspection of the leg length D1 of the welded portion 7. Therefore, the probe 14 can receive the reflection reflected by the terminal end 6a.
  • the reflected wave generated by the reflection of the ultrasonic wave at the portion of the weld metal 6 in contact with the differential case 1 has a higher reflectance than the reflected wave reflected on the terminal end 6a through the gap S1.
  • the reflected wave generated by the reflection of the ultrasonic wave on the abutting surface 2a via the gap S1 is attenuated by the gap S1, and therefore the reflectance is higher than the reflected wave reflected to the terminal end 6a via the gap S1. Is low.
  • the reflected wave generated in this way is received by the probe 14.
  • the personal computer 18 analyzes the echo height of the reflected wave received by the probe 14 and displays the analysis result on the display device 18b by the A scope, B scope, and C scope.
  • the reflected wave reflected on the terminal end 6a of the weld metal 6 has a lower echo height than the reflected wave reflected at the boundary between the weld metal 6 and the differential case 1, and has a higher echo height than the reflected wave reflected on the butt surface 2a. . Therefore, the lower end of the gap S1, that is, the end 6a of the weld metal 6 is visualized from the echo height and displayed on the display device 18b.
  • a gap S1 having a width B larger than the wavelength of the ultrasonic wave transmitted by the probe 14 is provided between the butted surface 2a of the ring gear 2 and the butted surface 1a of the differential case 1. Since the ultrasonic flaw detection system 11 can clearly detect whether or not the ultrasonic wave transmitted from the probe 14 is reflected by the terminal end 6a of the weld metal 6, the ring gear 2 and the differential case are provided. The leg length D2 of one welded portion 8 is inspected with high accuracy.
  • FIG. 7 is a cross-sectional view of the first embodiment.
  • 8 to 11 are diagrams showing screens for displaying the leg length inspection results of the first embodiment.
  • the ultrasonic flaw detection system 11 When performing the leg length inspection of the welded portion 7, the ultrasonic flaw detection system 11 has a frequency of 5 MHz, a sound velocity of 3080 m / s, and a wavelength of 0 from the probe 14 toward the “first target position” of the first to third embodiments. Transmit 60mm ultrasound. Further, when performing the leg length inspection of the welded portion 8, the flaw detection system 11 has a frequency of 10 MHz, a sound velocity of 3080 m / s, and a wavelength of 0 from the probe 14 toward the “second target position” of the first to third embodiments. .31mm ultrasonic waves are transmitted.
  • the ring gear 2 and the differential case 1 are differential gears having the same shape.
  • a thickness E in the axial direction (upper surface direction in the drawing) of the butting surface 1a of the differential case 1 and the butting surface 2a of the ring gear 2 is 23 mm.
  • the width B of the gap S1 (the radial width dimension B of the concave groove 1b) is set to 0.6 mm, which is larger than the wavelength of the ultrasonic wave.
  • gap part S1 is 20 mm.
  • the designed leg lengths D1 and D2 of the welded portions 7 and 8 are 3.0 mm. In the first to third embodiments, only the actual leg lengths D1 and D2 of the welded portions 7 and 8 are different.
  • the “first target position” is a range of ⁇ 5.0 mm (a range of 0 mm or more and 8.0 mm or less from the surface of the differential case 1) of the design position (3.0 mm from the surface) of the terminal end 5a.
  • the “second target position” is within a range of ⁇ 5.0 mm of the designed position of the terminal end 6a (3.0 mm from the back surface) (15.0 mm or more and 23.0 mm from the surface of the differential case 1). Range).
  • the ultrasonic flaw detection system 11 transmits an ultrasonic wave from the surface of the first embodiment to the “first target position” of the welded portion 7 and performs leg length inspection. As shown by the arrow in FIG. On the display screen, the luminance (color) at a position of a depth of 3.0 mm from the surface of the differential case 1 (position of 0 mm) was displayed separately from other portions. In addition, on the cross-section display screen of FIG. 9, it is displayed that the terminal end 5a of the weld metal 5 indicated by dot hatching protrudes downward into the gap S1 and the weld metal 5 is not damaged. .
  • the ultrasonic flaw detection system 11 transmits ultrasonic waves from the back surface of the first embodiment to the “second target position” of the welded portion 8 to perform leg length inspection.
  • the brightness (color) at a depth of 20.0 mm from the surface of the differential case 1 was displayed separately from other parts.
  • the cross-section display screen of FIG. 11 it is displayed that the terminal end 6a of the weld metal 6 indicated by dot hatching protrudes upward into the gap portion S1 and that the weld metal 6 is not damaged. .
  • the tester cuts the first embodiment along the portion where the ultrasonic wave was transmitted and measured the leg lengths D1 and D2 of the welded portions 7 and 8, respectively. 0.0 mm. Further, the tester did not find any scratches in the weld metals 5 and 6.
  • the ultrasonic flaw detection system 11 transmits an ultrasonic wave from the surface of the second embodiment to the “first target position” of the welded portion 7 and performs leg length inspection. As shown by the arrow in FIG. On the display screen, the luminance (color) at a depth of 2.0 mm from the surface of the differential case 1 was displayed separately from the other portions. In addition, on the cross-section display screen of FIG. 14, it is displayed that the end 5a of the weld metal 5 indicated by dot hatching has a small amount protruding into the gap S1 and that the weld metal 5 is not damaged. It was.
  • the ultrasonic flaw detection system 11 transmits ultrasonic waves from the back surface of the second embodiment to the “second target position” of the welded portion 8 to perform leg length inspection.
  • the brightness (color) at a position 21.0 mm deep from the surface of the differential case 1 was displayed separately from other parts.
  • the cross-section display screen of FIG. 16 it is displayed that the end 6a of the weld metal 6 displayed by dot hatching has a small amount protruding into the gap S1 and that the weld metal 6 is not damaged. It was.
  • the tester cut the second embodiment along the portion where the ultrasonic wave was transmitted and measured the leg lengths D1 and D2 of the welded portions 7 and 8, respectively. 0.0 mm. Further, the tester did not find any scratches inside the weld metals 5 and 6.
  • the ultrasonic flaw detection system 11 transmits an ultrasonic wave from the surface of the third embodiment to the “first target position” of the welded portion 7 and performs a leg length inspection. As shown by an arrow in FIG. On the display screen, the luminance (color) at a depth of 5.0 mm from the surface of the differential case 1 is displayed separately from the other portions. In addition, on the cross-section display screen of FIG. 19, it is displayed that the terminal end 5a of the weld metal 5 indicated by dot hatching protrudes greatly into the gap S1 and the weld metal 5 has a plurality of scratches. .
  • the ultrasonic flaw detection system 11 conducted the leg length inspection by transmitting ultrasonic waves from the back surface of the third embodiment to the “second target position” of the welded portion 8, as shown by the arrow in FIG.
  • the luminance (color) at a position 18.0 mm deep from the surface of the differential case 1 was displayed separately from other parts.
  • the tester cuts the third embodiment along the portion where the ultrasonic wave was transmitted and measured the leg lengths D1 and D2 of the welded portions 7 and 8, respectively. 0.0 mm. Then, the tester found a fine flaw 5 b inside the weld metal 5 and found two flaws 6 b inside the weld metal 6.
  • leg length inspection results displayed on the display device 18b of the first to third embodiments and the actual leg lengths D1 and D2 of the welded portions 7 and 8 formed in the first to third embodiments are as follows.
  • the leg lengths D1 and D2 of the welded portions 7 and 8 can be inspected with high accuracy.
  • scratches such as blow holes generated in the weld metals 5 and 6 could be found.
  • the present invention is not limited to the above embodiment, and various applications are possible.
  • the probe 14 is fixed and the differential gear 4 is rotated.
  • ultrasonic waves may be transmitted to the welded portions 7 and 8 of the differential gear 4 by fixing the differential gear 4 in water and moving the probe 14.
  • the leg length inspection of the welded portions 7 and 8 may be performed by sliding the probe 14 while rotating the differential gear 4.
  • the leg length inspection of the welding parts 7 and 8 was implemented in the state where the differential gear 4 and the probe 14 were submerged.
  • the leg length inspection of the welded portions 7 and 8 may be performed by applying jelly on the surface of the differential gear 4 and moving the probe 14 on the jelly.
  • the gap portion S1 is provided by one concave groove 1b.
  • the concave grooves 1b are provided in the portions corresponding to the design positions of the terminal ends 5a and 6a of the weld metals 5 and 6, respectively, and the two gaps S1 are provided between the butted surfaces 1a and 2a. good.
  • the concave groove 1 b is formed in the abutting surface 1 a of the differential case 1.
  • the gap S1 may be provided by forming a concave groove on the abutting surface 2a of the ring gear 2 and forming the favorite surface 1a of the differential case 1 flat.
  • groove may be formed in both the abutting surfaces 1a and 2a, and the space
  • the ultrasonic flaw detection system 11 can measure the leg lengths D ⁇ b> 1 and D ⁇ b> 2 corresponding to changes in the workpiece dimensions of the ring gear 2 and the differential case 1 by changing the wavelength and incident angle of the probe 14. it can.

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Abstract

A welding structure (10) is configured in such a manner that a first abutting surface (1a) of a differential case (1) and a second abutting surface (2a) of a ring gear (2) are abutted against each other, the ends of the abutted portions are welded by deposited metal (5, 6), an ultrasonic wave is applied to the welded portions (7, 8) which are welded by the deposited metal, and the length of the welded portions (7, 8) are tested by analyzing a reflected echo from a reflection source. A space (S1) having a width greater than the wavelength of the ultrasonic wave is formed between the first abutting surface (1a) and the second abutting surface (2a), and the space is formed by a groove (1b) formed in either the first abutting surface (1a) and/or the second abutting surface (2a). Ends (5a, 6a) of the deposited metal (5, 6) are exposed to the space (S1), and this allows the lengths (D1, D2) of the welded portions (7, 8) to be accurately tested.

Description

リングギアとデフケースの溶接構造Welding structure of ring gear and differential case
　本発明は、リングギアとデフケースの溶接構造に関する。 The present invention relates to a welded structure of a ring gear and a differential case.
　自動車の駆動機構に用いられるデフギアは、自動車の駆動輪を繋ぐシャフトに用いられ、自動車がカーブを曲がるときに内輪と外輪の速度差を吸収する差動装置の１つである。図２２は、特許文献１に記載されるデフギア１１０の断面図である。
　デフギア１１０は、デフケース１０１の外側に保持されるリングギア１０２と、デフケース１０１の組付スペース１０３に設けられ、デフケース１０１にピニオンシャフト１０４を介して取り付けられたピニオンギア１０５と、ピニオンギア１０５と噛み合うと共に車軸１０６に取り付けられる連結ギア１０７よりなる。
　自動車のエンジン等が発生する駆動力は、駆動力伝達ギア１０８から、デフケース１０１に接合されるリングギア１０２に伝達され、デフケース１０１とリングギア１０２が一体的に回転する。ピニオンギア１０５は、デフケース１０１の回転に従って回転し、連結ギア１０７を介して車軸１０６に駆動力を伝達する。 A differential gear used for a driving mechanism of an automobile is one of differential devices that are used for a shaft that connects driving wheels of an automobile and absorbs a speed difference between an inner ring and an outer ring when the automobile turns a curve. FIG. 22 is a cross-sectional view of the differential gear 110 described in Patent Document 1.
The differential gear 110 is provided in a ring gear 102 that is held outside the differential case 101, a space 103 in which the differential case 101 is assembled, and a pinion gear 105 that is attached to the differential case 101 via a pinion shaft 104, and meshes with the pinion gear 105. A connecting gear 107 attached to the axle 106 is also included.
The driving force generated by the automobile engine or the like is transmitted from the driving force transmission gear 108 to the ring gear 102 joined to the differential case 101, and the differential case 101 and the ring gear 102 rotate integrally. The pinion gear 105 rotates in accordance with the rotation of the differential case 101 and transmits a driving force to the axle 106 via the connecting gear 107.
　この他、自動車に用いられる差動装置としては、ＬＳＤと呼ばれる一方の車輪が無負荷状態の時に車軸を空転させてしまうデフギアの欠点を補った物も存在するが、デフケースの外側にリングギアを用いるという点では同じ構造となる。
　そして、この差動装置に備えるデフケース１０１にリングギア１０２を接合する方法は、従来ではボルトを用いて締結する方法が採られてきた。
　しかし、このボルトでの締結方法を用いると、ボルトの重量やボルトで締結するために必要な肉厚等を必要とするので、重量が増加する問題がある。 In addition, as a differential device used in an automobile, there is a thing that compensates for the disadvantage of the differential gear that causes the axle to idle when one wheel called LSD is in an unloaded state, but a ring gear is provided outside the differential case. The structure is the same in terms of use.
As a method of joining the ring gear 102 to the differential case 101 provided in the differential device, a method of fastening using a bolt has been conventionally employed.
However, when this bolt fastening method is used, the weight of the bolt, the thickness necessary for fastening with the bolt, and the like are required, which increases the weight.
　そこで、デフケースとリングギアを溶接接合し、重量を軽くする技術が提案されている。図２３は、従来の溶接構造１００を示す概略断面図である。
　従来の溶接構造１００は、リングギア１０２の突き合わせ面１０２ａをデフケース１０１の突き合わせ面１０１ａに圧入し、圧接された突き合わせ面１０１ａ，１０２ａの図中上側と図中下側に図示しない溶接ワイヤを溶かした溶着金属１０９を流し込むことにより、リングギア１０２とデフケース１０１が溶接接合されている。デフケース１０１は、自動車に取り付けられた後に振れなく回転する必要がある。デフケース１０１の振れは、自動車の静粛性や振動、及び、デフギア等の寿命などに影響するからである。 Therefore, a technique for reducing the weight by welding the differential case and the ring gear has been proposed. FIG. 23 is a schematic cross-sectional view showing a conventional welding structure 100.
In the conventional welding structure 100, the abutting surface 102a of the ring gear 102 is press-fitted into the abutting surface 101a of the differential case 101, and welding wires (not shown) are melted on the upper and lower sides of the abutting surfaces 101a and 102a in pressure contact. The ring gear 102 and the differential case 101 are welded and joined by pouring the welding metal 109. The differential case 101 needs to rotate without shaking after being attached to the automobile. This is because the shake of the differential case 101 affects the quietness and vibration of the automobile, the life of the differential gear, and the like.
　振れを防止するためには、リングギア１０２の突き合わせ面１０２ａとデフケース１０１の突き合わせ面１０１ａの溶接強度を設計値以上に確保する必要がある。溶接強度は、突き合わせ面１０１ａ，１０２ａを図中上面側から溶接した溶接部分１１１の図中上面からの長さ（脚長）Ｄ１１１と、突き合わせ面１０１ａ，１０２ａを図中下面側から溶接した溶接部分１１２の図中下面からの長さ（脚長）Ｄ１１２の影響を受ける。そこで、デフギア１１０は、溶接部分１１１，１１２の脚長Ｄ１１１，Ｄ１１２が設計値を満たしているか否かが、全数チェックされる。 In order to prevent vibration, it is necessary to secure the welding strength of the butted surface 102a of the ring gear 102 and the butted surface 101a of the differential case 101 to be higher than the design value. As for the welding strength, the length (leg length) D111 of the welded portion 111 where the butted surfaces 101a and 102a are welded from the upper surface side in the drawing and the welded portion 112 where the butted surfaces 101a and 102a are welded from the lower surface side in the drawing. It is influenced by the length (leg length) D112 from the lower surface in the figure. Therefore, all the differential gears 110 are checked to check whether or not the leg lengths D111 and D112 of the welded portions 111 and 112 satisfy the design values.
特開２００２－５３３６２７号公報JP 2002-533627 A
　しかしながら、従来、デフギア１１０の溶接部分１１１，１１２の脚長Ｄ１１１，Ｄ１１２は、図２４に示すように、探触子１２１が送信した超音波が溶着金属１０９の終端１０９ａに反射して発生する回折波（図中一点鎖線参照）を、探触子１２１により受信することにより、突き合わせ面１０１ａ，１０２ａの間に形成される隙間Ｓ１１と溶着金属１０９の終端１０９ａとの境界を検出して、検査されていた。この検査方法によれば、溶接部分１１１，１１２の脚長Ｄ１１１，Ｄ１１２を非破壊で測定できるからである。ところが、この検査方法では、隙間Ｓ１１の幅が狭いため、溶接部分１１１，１１２の脚長Ｄ１１１，Ｄ１１２を精度良く測定することができなかった。 Conventionally, however, the leg lengths D111 and D112 of the welded portions 111 and 112 of the differential gear 110 are diffracted waves generated by reflection of the ultrasonic wave transmitted by the probe 121 to the end 109a of the weld metal 109, as shown in FIG. (Refer to the one-dot chain line in the figure) is received by the probe 121, and the boundary between the gap S11 formed between the butted surfaces 101a and 102a and the end 109a of the weld metal 109 is detected and inspected. It was. This is because, according to this inspection method, the leg lengths D111 and D112 of the welded portions 111 and 112 can be measured nondestructively. However, in this inspection method, since the width of the gap S11 is narrow, the leg lengths D111 and D112 of the welded portions 111 and 112 cannot be accurately measured.
　例えば、図２４に示すように、溶接部分１１１の脚長Ｄ１１１を検査する場合、探触子１２１から溶接部分１１１を形成する溶着金属１０９の終端１０９ａへ向けて超音波が送信される。デフケース１０１とリングギア１０２の形状が複雑であるため、デフギア１１０の表面（又は裏面）に対して探触子１２１を配置できる場所は１箇所に限られる。また、溶着金属１０９が余盛を有するため、溶着金属１０９の終端１０９ａと隙間Ｓ１１との境界を検出するためには、探触子１２１が、デフケース１０１の上側（表面）から溶着金属１０９の終端１０９ａに向けて超音波を斜めに送信するようにしなければならない。そのため、溶接部分１１１の脚長検査では、デフケース１０１に対して一方向に探触子１２１を配置し、探触子１２１から送信される超音波を溶着金属１０９の終端１０９ａに反射させて図中一点鎖線に示す回折波を生じさせ、その回折波を探触子１２１に受信させることにより、脚長Ｄ１１１，Ｄ１１２が検査される。 For example, as shown in FIG. 24, when the leg length D111 of the welded portion 111 is inspected, ultrasonic waves are transmitted from the probe 121 toward the end 109a of the weld metal 109 forming the welded portion 111. Since the shapes of the differential case 101 and the ring gear 102 are complicated, the location where the probe 121 can be disposed on the front surface (or the back surface) of the differential gear 110 is limited to one. In addition, since the weld metal 109 has a surplus, in order to detect the boundary between the end 109a of the weld metal 109 and the gap S11, the probe 121 is connected to the end of the weld metal 109 from the upper side (surface) of the differential case 101. It is necessary to transmit ultrasonic waves obliquely toward 109a. Therefore, in the leg length inspection of the welded portion 111, the probe 121 is arranged in one direction with respect to the differential case 101, and the ultrasonic wave transmitted from the probe 121 is reflected on the terminal end 109a of the weld metal 109 to be one point in the figure. The leg lengths D111 and D112 are inspected by generating a diffracted wave indicated by a chain line and causing the probe 121 to receive the diffracted wave.
　探触子１２１が検出可能な最小サイズは、探触子１２１から送信される超音波の波長と同程度の大きさである。そのため、溶着金属１０９の終端１０９ａと隙間Ｓ１１との間の境界を検出するためには、隙間Ｓ１１の幅Ｗが少なくとも超音波の波長と同程度の大きさを有する必要がある。ところが、従来の溶接構造１００は、平坦な突き合わせ面１０１ａと平坦な突き合わせ面１０２ａとの間に隙間Ｓ１１が形成されていたため、隙間Ｓ１１の幅Ｗが、僅かに数μｍあるだけで、探触子１２１から送信される超音波の波長（例えば０．３０ｍｍ）より大幅に短かった。よって、従来の溶接構造１００では、超音波が溶着金属１０９の終端１０９ａに反射しても、微弱な回折波しか発生せず、回折波に基づいて溶接部分１１１の脚長Ｄ１１１を精度良く検出することができなかった。
　尚、図２４は、従来の脚長検査のイメージ図である。 The minimum size that can be detected by the probe 121 is about the same as the wavelength of the ultrasonic wave transmitted from the probe 121. Therefore, in order to detect the boundary between the terminal end 109a of the weld metal 109 and the gap S11, the width W of the gap S11 needs to be at least as large as the wavelength of the ultrasonic wave. However, in the conventional welded structure 100, since the gap S11 is formed between the flat butted surface 101a and the flat butted surface 102a, the width W of the gap S11 is only a few μm. It was much shorter than the wavelength of the ultrasonic wave transmitted from 121 (for example, 0.30 mm). Therefore, in the conventional welding structure 100, even if the ultrasonic wave is reflected on the end 109a of the weld metal 109, only a weak diffracted wave is generated, and the leg length D111 of the welded portion 111 is accurately detected based on the diffracted wave. I could not.
FIG. 24 is an image diagram of a conventional leg length inspection.
　本発明は、上記課題を解決するためになされたものであり、リングギアとデフケースの溶接部分の長さが精度良く検査されるリングギアとデフケースの溶接構造を提供することを目的とする。 The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a ring gear and differential case welding structure in which the length of the welded portion of the ring gear and differential case is accurately inspected.
  上記課題を解決するために、本発明の一態様に係る溶接構造は、デフケースの第１突き合わせ面とリングギアの第２突き合わせ面とが突き合わされ、突き合わされた部分の端部が溶着金属により溶接されており、前記溶着金属により溶接された溶接部分に超音波を照射され、反射源から反射するエコーを解析することにより前記溶接部分の長さが検査される溶接構造において、前記第１突き合わせ面と前記第２突き合わせ面との間に、前記超音波の波長より大きい幅の空隙部が形成されており、前記空隙部は、前記第１突き合わせ面又は前記第２突き合わせ面の少なくとも一方に形成された凹溝により形成され、前記溶着金属の終端が前記空隙部に露出している。 In order to solve the above-described problem, a welding structure according to one aspect of the present invention is such that the first butted surface of the differential case and the second butted surface of the ring gear are abutted, and the end of the abutted portion is welded by a weld metal. In the welding structure in which the welded portion welded with the weld metal is irradiated with ultrasonic waves and the length of the welded portion is inspected by analyzing an echo reflected from a reflection source, the first abutting surface And a gap having a width larger than the wavelength of the ultrasonic wave, and the gap is formed on at least one of the first abutting surface and the second abutting surface. The end of the weld metal is exposed in the gap.
　上記構成の溶接構造は、前記第１及び前記第２突き合わせ面が環状に設けられ、前記溶接部分は、前記第１及び前記第２突き合わせ面の一端から溶接された第１溶接部分と、前記第１及び前記第２突き合わせ面の他端から溶接された第２溶接部とを含み、前記第１及び第２溶接部分が前記空隙部に露出していることが好ましい。 In the welding structure having the above-described configuration, the first and second butting surfaces are provided in an annular shape, and the welding portion includes a first welding portion welded from one end of the first and second butting surfaces, and the first 1 and a second welded portion welded from the other end of the second butting surface, and the first and second welded portions are preferably exposed in the gap.
　上記態様の溶接構造によれば、デフケースの第１突き合わせ面又はリングギアの第２突き合わせ面の少なくとも一方に凹溝が形成され、第１突き合わせ面と第２突き合わせ面との間に空隙部が設けられている。空隙部の幅が超音波の波長より大きいため、超音波は、空隙部に露出する溶着金属の終端に送信されて反射すると、空隙部内へ分散し、他の部分に反射する場合と異なる反射波を発生する。そのため、超音波の反射波を解析することにより、溶着金属の終端と空隙部との境界を検出し、溶接部分の長さを測定できる。よって、上記態様の溶接構造によれば、溶接部分の長さが精度良く検査される。 According to the welded structure of the above aspect, a concave groove is formed in at least one of the first butted surface of the differential case or the second butted surface of the ring gear, and a gap is provided between the first butted surface and the second butted surface. It has been. Since the width of the gap is larger than the wavelength of the ultrasonic wave, when the ultrasonic wave is transmitted and reflected at the end of the weld metal exposed in the gap, the reflected wave is dispersed into the gap and reflected to other parts. Is generated. Therefore, by analyzing the reflected wave of the ultrasonic wave, the boundary between the end of the weld metal and the gap can be detected, and the length of the welded portion can be measured. Therefore, according to the welding structure of the said aspect, the length of a welding part is test | inspected accurately.
　上記構成の溶接構造は、環状に設けられた第１突き合わせ面と第２突き合わせ面を突き合わせ、第１及び第２突き合わせ面の一端から溶接を行って第１溶接部分を形成すると共に、第１及び第２突き合わせ面の他端から溶接を行って第２溶接部分を形成している。第１及び第２溶接部分は、空隙部に露出している。よって、上記構成の溶接構造によれば、第１及び第２溶接部分に超音波を送信してその反射波が解析されることにより、第１及び第２溶接部分を形成する溶着金属の終端の位置がそれぞれ精度良く検査される。 The weld structure having the above-described configuration is formed by abutting a first butting surface and a second butting surface provided in an annular shape, and welding is performed from one end of the first and second butting surfaces to form a first welding portion. Welding is performed from the other end of the second butting surface to form a second welded portion. The first and second welded portions are exposed in the gap. Therefore, according to the welding structure having the above-described configuration, the ultrasonic waves are transmitted to the first and second welded portions, and the reflected waves are analyzed, whereby the terminal end of the weld metal forming the first and second welded portions is analyzed. Each position is inspected with high accuracy.
本発明の第１実施形態に係り、溶接構造を適用したデフギアの外観を示すイメージ図である。It is an image figure which shows the external appearance of the differential gear which concerns on 1st Embodiment of this invention and applied the welding structure. 溶接される前のリングギアとデフケースの部分断面図である。It is a fragmentary sectional view of the ring gear and differential case before welding. 図１のＡ部拡大断面図である。It is the A section expanded sectional view of FIG. 超音波探傷システムの概略構成図である。It is a schematic block diagram of an ultrasonic flaw detection system. デフギアの表面側溶接部分の脚長を検査するイメージを示す図である。It is a figure which shows the image which test | inspects the leg length of the surface side welding part of a differential gear. デフギアの裏面側溶接部分の脚長を検査するイメージを示す図である。It is a figure which shows the image which test | inspects the leg length of the back surface side welding part of a differential gear. 第１実施例の断面図である。It is sectional drawing of 1st Example. 第１実施例の表面側溶接部分の脚長検査結果を示す図であって、Ｂスコープの表示画面を示す。It is a figure which shows the leg length test result of the surface side welding part of 1st Example, Comprising: The display screen of B scope is shown. 第１実施例の表面側溶接部分の脚長検査結果を示す図であって、断面表示画面を示す。It is a figure which shows the leg length test result of the surface side welding part of 1st Example, Comprising: A cross-section display screen is shown. 第１実施例の裏面側溶接部分の脚長検査結果を示す図であって、Ｂスコープの表示画面を示す。It is a figure which shows the leg length test result of the back surface side welding part of 1st Example, Comprising: The display screen of B scope is shown. 第１実施例の裏面側溶接部分の脚長検査結果を示す図であって、断面表示画面を示す。It is a figure which shows the leg length test result of the back surface side weld part of 1st Example, Comprising: A cross-section display screen is shown. 第２実施例の断面図である。It is sectional drawing of 2nd Example. 第２実施例の表面側溶接部分の脚長検査結果を示す図であって、Ｂスコープの表示画面を示す。It is a figure which shows the leg length test result of the surface side welding part of 2nd Example, Comprising: The display screen of B scope is shown. 第２実施例の表面側溶接部分の脚長検査結果を示す図であって、断面表示画面を示す。It is a figure which shows the leg length test result of the surface side welding part of 2nd Example, Comprising: A cross-section display screen is shown. 第２実施例の裏面側溶接部分の脚長検査結果を示す図であって、Ｂスコープの表示画面を示す。It is a figure which shows the leg length test result of the back surface side weld part of 2nd Example, Comprising: The display screen of B scope is shown. 第２実施例の裏面側溶接部分の脚長検査結果を示す図であって、断面表示画面を示す。It is a figure which shows the leg length test result of the back surface side welding part of 2nd Example, Comprising: A cross-section display screen is shown. 第３実施例の断面図である。It is sectional drawing of 3rd Example. 第３実施例の表面側溶接部分の脚長検査結果を示す図であって、Ｂスコープの表示画面を示す。It is a figure which shows the leg length test result of the surface side welding part of 3rd Example, Comprising: The display screen of B scope is shown. 第３実施例の表面側溶接部分の脚長検査結果を示す図であって、断面表示画面を示す。It is a figure which shows the leg length test result of the surface side welding part of 3rd Example, Comprising: A cross-section display screen is shown. 第３実施例の裏面側溶接部分の脚長検査結果を示す図であって、Ｂスコープの表示画面を示す。It is a figure which shows the leg length test result of the back surface side welding part of 3rd Example, Comprising: The display screen of B scope is shown. 第３実施例の裏面側溶接部分の脚長検査結果を示す図であって、断面表示画面を示す。It is a figure which shows the leg length test result of the back surface side weld part of 3rd Example, Comprising: A cross-section display screen is shown. 特許文献１に記載されるデフギアの断面図である。2 is a cross-sectional view of a differential gear described in Patent Document 1. FIG. 従来の溶接構造を示す概略断面図である。It is a schematic sectional drawing which shows the conventional welding structure. 従来の脚長検査のイメージ図である。It is an image figure of the conventional leg length test | inspection.
１　デフケース
１ａ　突き合わせ面
１ｂ　凹溝
２　リングギア
２ａ　突き合わせ面
４　デフギア
５，６　溶着金属
５ａ，６ａ　終端
７，８　溶接部分
１０　溶接構造
Ｓ１　空隙部 DESCRIPTION OF SYMBOLS 1 Differential case 1a Butting surface 1b Groove 2 Ring gear 2a Butting surface 4 Differential gears 5, 6 Weld metal 5a, 6a Termination 7, 8 Welding part 10 Welding structure S1 Gap
　次に、本発明に係る溶接構造の一実施形態について図面を参照して説明する。 Next, an embodiment of a welding structure according to the present invention will be described with reference to the drawings.
＜溶接構造の概略構成＞
　図１は、本発明の第１実施形態に係り、リングギア２とデフケース１の溶接構造１０を適用したデフギア４の外観を示すイメージ図である。図２は、溶接される前のリングギア２とデフケース１の部分断面図である。図３は、図１のＡ部拡大断面図である。
  図１に示すデフギア４は、従来技術と同様、自動車に使用される。デフギア４は、図２に示すように、リングギア２の突き合わせ面２ａをデフケース１の突き合わせ面１ａに圧入した後、図３に示すように、突き合わせ面１ａ，２ａをデフギア４の表面側（図中上側）と裏面側（図中下側）から溶接した溶接構造１０を適用している。溶接構造１０は、超音波探傷システム１１を用いて溶接部分７，８の長さ（脚長）Ｄ１，Ｄ２を精度良く測定するために、リングギア２の突き合わせ面２ａとデフケース１の突き合わせ面１ａの間に、超音波の波長より大きい幅Ｂの空隙部Ｓ１が設けられている。 <Schematic configuration of welded structure>
FIG. 1 is an image diagram showing an appearance of a differential gear 4 to which a welded structure 10 of a ring gear 2 and a differential case 1 is applied according to the first embodiment of the present invention. FIG. 2 is a partial cross-sectional view of the ring gear 2 and the differential case 1 before being welded. FIG. 3 is an enlarged cross-sectional view of a portion A in FIG.
The differential gear 4 shown in FIG. 1 is used for an automobile as in the prior art. As shown in FIG. 2, the differential gear 4 press-fits the butting surface 2a of the ring gear 2 into the butting surface 1a of the differential case 1, and then, as shown in FIG. 3, the butting surfaces 1a and 2a are placed on the surface side of the differential gear 4 (see FIG. The welding structure 10 welded from the middle upper side and the back side (lower side in the figure) is applied. In order to accurately measure the lengths (leg lengths) D1 and D2 of the welded portions 7 and 8 using the ultrasonic flaw detection system 11, the welded structure 10 includes a butt surface 2a of the ring gear 2 and a butt surface 1a of the differential case 1. A gap S1 having a width B larger than the wavelength of the ultrasonic wave is provided therebetween.
　図１及び図２に示すように、リングギア２は、鋳鉄などの金属を材質とする。リングギア２は、略円筒形状に成形されている。リングギア２の外周面には、駆動力伝達ギア１０８（図２２参照）に噛合されるギア部２ｂが、リングギア２と同軸上に形成されている。図２に示すように、リングギア２の内周面には、環状の突き合わせ面２ａがリングギア２と同軸上に形成されている。突き合わせ面２ａは、リングギア２の図中上下方向の軸線に対して平行な平坦面により形成されている。 1 and 2, the ring gear 2 is made of a metal such as cast iron. The ring gear 2 is formed in a substantially cylindrical shape. A gear portion 2 b meshed with the driving force transmission gear 108 (see FIG. 22) is formed on the outer peripheral surface of the ring gear 2 so as to be coaxial with the ring gear 2. As shown in FIG. 2, an annular butting surface 2 a is formed coaxially with the ring gear 2 on the inner peripheral surface of the ring gear 2. The butting surface 2a is formed by a flat surface parallel to the vertical axis of the ring gear 2 in the drawing.
　一方、図１及び図２に示すように、デフケース１は、鋳鉄などの金属を材質とする。デフケース１は、略円筒形状に成形されている。図２に示すように、デフケース１の一端外周面には、突き合わせ面１ａが環状に形成されている。突き合わせ面１ａは、デフケース１と同軸上に形成されている。突き合わせ面１ａは、デフケース１の図中上下方向の軸線に対して平行な平坦面により形成されている。突き合わせ面１ａは、外径寸法Ｘ１が突き合わせ面２ａの内径寸法Ｘ２より大径に設定され、突き合わせ面２ａを突き合わせ面１ａに圧入するための圧入代を設けられている。凹溝１ｂは、突き合わせ面１ａの中央部に沿って、環状に形成されている。 On the other hand, as shown in FIGS. 1 and 2, the differential case 1 is made of a metal such as cast iron. The differential case 1 is formed in a substantially cylindrical shape. As shown in FIG. 2, a butt surface 1 a is formed in an annular shape on the outer peripheral surface of one end of the differential case 1. The abutting surface 1 a is formed coaxially with the differential case 1. The abutting surface 1a is formed by a flat surface parallel to the vertical axis of the differential case 1 in the drawing. The abutting surface 1a has an outer diameter dimension X1 larger than the inner diameter dimension X2 of the abutting surface 2a, and is provided with a press-fitting allowance for press-fitting the abutting surface 2a into the abutting surface 1a. The concave groove 1b is formed in an annular shape along the central portion of the abutting surface 1a.
　図３に示す溶接構造１０は、デフケース１の突き合わせ面１ａにリングギア２の突き合わせ面２ａを圧入することにより、デフケース１とリングギア２が同軸上に位置決めされている。圧接される突き合わせ面１ａ，２ａは、図中上側（表面側）に熱を加えられて溶かされ、その溶かされた部分に図示しない溶接ワイヤを溶かした溶着金属５が溶かし込まれる。これにより、突き合わせ面１ａ，２ａは、表面側から所定の長さ（脚長）Ｄ１だけ溶接され、溶接部分７が形成されている。これと同様に、突き合わせ面１ａ，２ａは、溶着金属６により図中下側（裏面側）から所定の長さ（脚長）Ｄ２だけ溶接され、溶接部分８が形成されている。デフギア４を自動車に組み付けて使用すると、駆動力伝達ギア１０８（図２２参照）からリングギア２に伝達された回転トルクが、突き合わせ面１ａ，２ａの圧入部分と溶接部分７，８に作用する。溶着金属５，６の脚長Ｄ１，Ｄ２は、その回転トルクに対する耐久性が確保されるように、設定される。このように溶接接合された突き合わせ面１ａ，２ａの間には、凹溝１ｂにより、空隙部Ｓ１が環状に形成されている。 3, the differential case 1 and the ring gear 2 are coaxially positioned by press-fitting the butted surface 2 a of the ring gear 2 into the butted surface 1 a of the differential case 1. The butted surfaces 1a and 2a to be pressed are melted by applying heat to the upper side (surface side) in the figure, and a weld metal 5 in which a welding wire (not shown) is melted is melted into the melted portion. As a result, the butted surfaces 1a and 2a are welded by a predetermined length (leg length) D1 from the surface side, and a welded portion 7 is formed. Similarly, the butted surfaces 1a and 2a are welded to the welding metal 6 by a predetermined length (leg length) D2 from the lower side (back side) in the figure to form a welded portion 8. When the differential gear 4 is assembled and used in an automobile, the rotational torque transmitted from the driving force transmission gear 108 (see FIG. 22) to the ring gear 2 acts on the press-fitted portions of the butted surfaces 1a and 2a and the welded portions 7 and 8. The leg lengths D1 and D2 of the weld metals 5 and 6 are set so as to ensure durability against the rotational torque. A gap S1 is formed in an annular shape between the butted surfaces 1a and 2a that are welded in this way, due to the concave groove 1b.
　空隙部Ｓ１の幅Ｂ、すなわち、凹溝１ｂの突き合わせ面１ａからデフケース１の径方向（図中左右方向）幅寸法Ｂは、超音波探傷システム１１（探触子１４）が検出できる最小検出サイズより大きく設定されている。空隙部Ｓ１の幅Ｂは、例えば、超音波探傷システム１１に使用される超音波（探触子１４から送信される超音波）の波長に対して９５％以上の大きさに設定され、超音波の波長と同程度とすることが好ましい。例えば、探触子１４から送信される超音波は、周波数が１０ＭＨｚ、音速が３０８０ｍ／ｓである場合、波長が０．３１ｍｍとなる。この場合、空隙部Ｓ１の幅Ｂは、０．３０ｍｍ以上に設定される。
　また、空隙部Ｓ１の軸方向長さＣ、すなわち、凹溝１ｂのデフケース１の軸方向（図中上下方向）の溝幅Ｃは、溶着金属５の終端５ａの設計上の位置と溶着金属６の終端６ａの設計上の位置との間の距離より広くなるように、設定されている。 The width B of the gap S1, that is, the radial dimension (horizontal direction in the figure) of the differential case 1 from the butted surface 1a of the groove 1b is the minimum detection size that can be detected by the ultrasonic flaw detection system 11 (probe 14). It is set larger. For example, the width B of the gap S1 is set to a size of 95% or more with respect to the wavelength of the ultrasonic wave (ultrasonic wave transmitted from the probe 14) used in the ultrasonic flaw detection system 11. It is preferable to set it to the same level as the wavelength. For example, the ultrasonic wave transmitted from the probe 14 has a wavelength of 0.31 mm when the frequency is 10 MHz and the sound velocity is 3080 m / s. In this case, the width B of the gap S1 is set to 0.30 mm or more.
Further, the axial length C of the gap S1, that is, the groove width C in the axial direction (vertical direction in the figure) of the differential groove 1b is determined by the design position of the terminal end 5a of the weld metal 5 and the weld metal 6 It is set so as to be wider than the distance from the design position of the end 6a.
　溶融した溶着金属５，６は、空気やほこりなどを含むことがある。本実施形態の溶接構造１０は、突き合わせ面１ａ，２ａの間に空隙部Ｓ１が形成され、その空隙部Ｓ１に溶着金属５，６の終端５ａ，６ａを露出させるように、溶接部分７，８が形成される。そのため、溶着金属５，６に含まれる空気やほこり等は、空隙部Ｓ１に露出する溶着金属５，６の表面に浮き出し、溶着金属５，６の内部に残りにくい。よって、溶着金属５，６の内部に、ブローホールが発生しにくい。ブローホールの発生を低減することにより、デフギア４は、駆動力伝達ギア１０８（図２２参照）から伝達される回転トルクが突き合わせ面１ａ，２ａの圧入部分と溶接部分７，８に作用しても、ブローホール発生部分に応力が集中せず、溶接部分７，８の耐久性が向上する。 The melted weld metals 5 and 6 may contain air or dust. In the welded structure 10 of the present embodiment, a gap S1 is formed between the butted surfaces 1a and 2a, and the welded portions 7 and 8 are so exposed that the terminal ends 5a and 6a of the weld metals 5 and 6 are exposed in the gap S1. Is formed. Therefore, the air, dust, etc. contained in the weld metals 5 and 6 float on the surface of the weld metals 5 and 6 exposed in the space S1 and hardly remain in the weld metals 5 and 6. Therefore, blowholes are not easily generated inside the weld metals 5 and 6. By reducing the occurrence of blowholes, the differential gear 4 can be applied even if the rotational torque transmitted from the driving force transmission gear 108 (see FIG. 22) acts on the press-fitted portions of the butted surfaces 1a and 2a and the welded portions 7 and 8. The stress is not concentrated on the blowhole generating portion, and the durability of the welded portions 7 and 8 is improved.
＜超音波探傷システムの概略構成＞
　図４は、超音波探傷システム１１の概略構成図である。
　超音波探傷システム１１は、デフギア４に凹凸が多く、しかも、デフギア４の突き合わせ面１ａ，２ａの溶接部分７，８に溶着金属５，６の余盛があるため、１個の探触子１４を用いた斜角探傷法を採用する。本実施形態の超音波探傷システム１１は、システム自体に、ＳＯＮＩＸ社のＦｌｅｘ　Ｓｃａｎ　Ｓｙｓｔｅｍ　ＦＬＸ－７４３Ｇ（型番）を使用し、使用水浸型探触子に、オリンパス製のＶ３１１　１０ＭＨｚ（型番）とオリンパス製のＭ３０９　５ＭＨｚ（型番）と特注品（型番なし）を使用して、構成されている。 <Schematic configuration of ultrasonic flaw detection system>
FIG. 4 is a schematic configuration diagram of the ultrasonic flaw detection system 11.
In the ultrasonic flaw detection system 11, the differential gear 4 has many irregularities, and the welded portions 7 and 8 of the abutting surfaces 1 a and 2 a of the differential gear 4 have surplus deposits 5 and 6. The oblique angle flaw detection method using is adopted. The ultrasonic flaw detection system 11 of the present embodiment uses a Flex Scan System FLX-743G (model number) manufactured by SONIX as the system itself, and the water immersion type probe used is Olympus V311 10 MHz (model number). It is configured using M309 5MHz (model number) and a custom-made product (no model number).
　超音波探傷システム１１は、主に、水槽１２と、探触子１４と、回転装置１５と、パルサーレシーバー１６と、ＡＤ／ＤＡ変換ボード１７と、パソコン１８を備える。
　水槽１２は、水１３が張られている。
　探触子１４は、水槽１２内に水浸された状態で保持され、超音波の送信と受信を行う振動子を内蔵している。本実施形態では、複数の振動子を備えており、複数の振動子の励磁タイミングをずらすことにより、超音波を集束させ、超音波の送信方向を変更することができるフェーズドアレイ型探触子を、探触子１４に使用している。
　回転装置１５は、水槽１２の底に配置されて被検査体となるデフギア４を回転させるものである。
　パルサーレシーバー１６は、探触子１４の振動子に接続され、探触子１４からデフギア４へ送信する超音波を制御するための電気信号を振動子に出力する一方、振動子が受信したエコーを入力して電気信号に変換するものである。
　ＡＤ／ＤＡ変換ボード１７は、アナログ信号とデジタル信号を相互変換するものである。
　パソコン１８は、入力装置１８ａと表示装置１８ｂと図示しない内部記憶装置を備える周知のコンピュータである。図示しない内部記憶装置には、図示しない解析ソフトが記憶されている。図示しない解析ソフトは、入力装置１８ａに入力されたパラメータを用いて探触子１４から送信する超音波を制御し、探触子１４が受信したエコーを解析してその解析結果を表示装置１８ｂに表示する。 The ultrasonic flaw detection system 11 mainly includes a water tank 12, a probe 14, a rotating device 15, a pulsar receiver 16, an AD / DA conversion board 17, and a personal computer 18.
The water tank 12 is filled with water 13.
The probe 14 is held in a state where it is immersed in the water tank 12, and has a built-in transducer for transmitting and receiving ultrasonic waves. In the present embodiment, a phased array type probe that includes a plurality of transducers and can focus the ultrasonic waves and change the transmission direction of the ultrasonic waves by shifting the excitation timing of the plurality of transducers. , Used for the probe 14.
The rotating device 15 is arranged at the bottom of the water tank 12 to rotate the differential gear 4 that becomes an object to be inspected.
The pulsar receiver 16 is connected to the transducer of the probe 14 and outputs an electrical signal for controlling an ultrasonic wave transmitted from the probe 14 to the differential gear 4 to the transducer, while receiving an echo received by the transducer. It is input and converted into an electrical signal.
The AD / DA conversion board 17 mutually converts an analog signal and a digital signal.
The personal computer 18 is a known computer including an input device 18a, a display device 18b, and an internal storage device (not shown). Analysis software (not shown) is stored in an internal storage device (not shown). Analysis software (not shown) controls ultrasonic waves transmitted from the probe 14 using parameters input to the input device 18a, analyzes echoes received by the probe 14, and displays the analysis results on the display device 18b. indicate.
＜溶接部分の脚長検査方法＞
　次に、超音波探傷システム１１を用いた溶接部分７，８の脚長Ｄ１，Ｄ２の検査方法について説明する。
　試験者は、図３に示すように、被検査体となるデフギア４を水槽１２に張った水１３に沈め、回転装置１５に載せる。試験者が、図４に示すパソコン１８により図示しない解析ソフトを起動すると、入力装置１８ａに初期画面が表示される。試験者が、検査に必要なパラメータ（デフケース１とリングギア２の材質や、デフケース１とリングギア２を通過する超音波の音速等）と、溶接部分７の脚長検査を開始する開始指示をパソコン１８の入力装置１８ａに入力すると、超音波探傷システム１１が溶接部分７の脚長検査を開始する。 <Leg length inspection method for welded parts>
Next, an inspection method for the leg lengths D1 and D2 of the welded portions 7 and 8 using the ultrasonic flaw detection system 11 will be described.
As shown in FIG. 3, the tester submerges the differential gear 4 serving as an object to be inspected in water 13 stretched on the water tank 12 and places it on the rotating device 15. When the tester activates analysis software (not shown) using the personal computer 18 shown in FIG. 4, an initial screen is displayed on the input device 18a. The tester gives parameters necessary for the inspection (such as the material of the differential case 1 and the ring gear 2 and the sound velocity of the ultrasonic wave passing through the differential case 1 and the ring gear 2) and a start instruction for starting the leg length inspection of the welded portion 7. When input is made to the 18 input devices 18 a, the ultrasonic flaw detection system 11 starts the leg length inspection of the welded portion 7.
　具体的には、パソコン１８は、所定の周波数、所定の帯域、所定の波長を有する超音波を探触子１４から送信する制御信号を出力する。制御信号は、ＡＤ／ＤＡ変換ボード１７によりデジタル信号からアナログ信号に変換され、パルサーレシーバー１６から探触子１４の振動子に送信される。 Specifically, the personal computer 18 outputs a control signal for transmitting ultrasonic waves having a predetermined frequency, a predetermined band, and a predetermined wavelength from the probe 14. The control signal is converted from a digital signal to an analog signal by the AD / DA conversion board 17 and transmitted from the pulsar receiver 16 to the transducer of the probe 14.
　図５は、デフギア４の表面側溶接部分７の脚長Ｄ１を検査するイメージを示す図である。
　探触子１４は、図５に示すように、溶着金属５の終端５ａが設計上存在する位置を含む所定範囲（以下「第１目標位置」という。）へ向けて、超音波を所定の周波数で送信する。これと同時に、回転装置１５が回転し、デフギア４を１回転させる。これにより、超音波が送信される位置が、デフギア４の円周方向へずらされる。 FIG. 5 is a diagram showing an image for inspecting the leg length D1 of the surface-side welded portion 7 of the differential gear 4.
As shown in FIG. 5, the probe 14 emits ultrasonic waves at a predetermined frequency toward a predetermined range (hereinafter referred to as “first target position”) including a position where the end 5 a of the weld metal 5 exists by design. Send with. At the same time, the rotating device 15 rotates to rotate the differential gear 4 once. Thereby, the position where the ultrasonic wave is transmitted is shifted in the circumferential direction of the differential gear 4.
　探触子１４から送信される超音波は、水１３を介してデフギア４のデフケース１に入射する。水１３は、探触子１４とデフケース１との間に介在して、超音波の伝播効率を高めている。超音波は、水１３からデフケース１の表面に入射する際に屈折し、デフケース１内を「第１目標位置」へ向かって伝播する。 The ultrasonic wave transmitted from the probe 14 enters the differential case 1 of the differential gear 4 through the water 13. The water 13 is interposed between the probe 14 and the differential case 1 to enhance the propagation efficiency of ultrasonic waves. The ultrasonic waves are refracted when entering the surface of the differential case 1 from the water 13 and propagate in the differential case 1 toward the “first target position”.
　溶着金属５は、終端５ａが空隙部Ｓ１に露出している。終端５ａは、空隙部Ｓ１へ流れ出るようにして固化している。終端５ａへ向かって送信された超音波は、空隙部Ｓ１を介してデフケース１側からリングギア２側へ回り込むように伝播し、図５の一点鎖線に示すような回折波を生じる。空隙部Ｓ１の幅が超音波の波長と同程度に設定されているため、発生した回折波が、干渉による減衰を生じにくい。よって、終端５ａに反射して生じた回折波は、探触子１４に受信される。
　一方、溶着金属５のデフケース１に接する部分や、空隙部Ｓ１を形成する突き合わせ面２ａに送信された超音波は、それらの裏側に回り込まずに反射される。その反射波は、探触子１４に受信される。 The end 5a of the weld metal 5 is exposed in the gap S1. The end 5a is solidified so as to flow out to the gap S1. The ultrasonic wave transmitted toward the terminal end 5a propagates from the differential case 1 side to the ring gear 2 side through the gap S1, and generates a diffracted wave as shown by a one-dot chain line in FIG. Since the width of the gap S1 is set to be approximately the same as the wavelength of the ultrasonic wave, the generated diffracted wave is not easily attenuated by interference. Therefore, the diffracted wave generated by reflection at the terminal end 5 a is received by the probe 14.
On the other hand, the ultrasonic waves transmitted to the part of the weld metal 5 that contacts the differential case 1 and the abutting surface 2a that forms the gap S1 are reflected without going around the back side. The reflected wave is received by the probe 14.
　超音波探傷システム１１は、探触子１４が「第１目標位置」に向かって超音波を送信するため、溶着金属５の終端５ａが設計上配置される位置を含む所定範囲について、回折波が発生する位置を検査できる。つまり、終端５ａの位置が設計上の位置からずれた場合でも、終端５ａを検出できる。 In the ultrasonic flaw detection system 11, since the probe 14 transmits ultrasonic waves toward the “first target position”, a diffracted wave is generated in a predetermined range including a position where the end 5a of the weld metal 5 is designed. The position where it occurs can be inspected. That is, even when the position of the terminal 5a is deviated from the designed position, the terminal 5a can be detected.
　また、超音波探傷システム１１は、探触子１４が水槽１２内の定位置に保持されているが、デフギア４が回転装置１５により１回転されるため、デフギア４の全周方向に沿って、回折波が発生する位置や領域を検査できる。 In the ultrasonic flaw detection system 11, the probe 14 is held at a fixed position in the water tank 12, but the differential gear 4 is rotated once by the rotating device 15, and therefore, along the entire circumferential direction of the differential gear 4, The position and area where the diffracted wave is generated can be inspected.
　パルサーレシーバー１６は、探触子１４が受信した回折波又は反射波を電気信号に変換し、ＡＤ／ＤＡ変換ボード１７に送信する。ＡＤ／ＤＡ変換ボード１７は、受信した電気信号をアナログ信号からデジタル信号に変換し、パソコン１８に送信する。 The pulsar receiver 16 converts the diffracted wave or reflected wave received by the probe 14 into an electric signal and transmits it to the AD / DA conversion board 17. The AD / DA conversion board 17 converts the received electrical signal from an analog signal to a digital signal and transmits it to the personal computer 18.
　パソコン１８は、ＡＤ／ＤＡ変換ボード１７から受信した電気信号を解析し、その解析結果を図示しない内部記憶装置に蓄積して記憶する。そして、パソコン１８は、解析結果を表示装置１８ｂに表示して可視化する。表示装置１８ｂには、少なくともＡスコープ（基本表示：時間軸のエコー高さを表示）、Ｂスコープ（断面表示：探触子１４の位置と終端５ａ，６ａの深さ位置を表示）、Ｃスコープ（平面表示：終端５ａ，６ａの表面表示）による表示画面が表示される。尚、これらの表示画面は、一画面にまとめて表示されてもよいし、試験者が切り替えて選択的に表示されるようにしても良い。 The personal computer 18 analyzes the electrical signal received from the AD / DA conversion board 17 and accumulates and stores the analysis result in an internal storage device (not shown). Then, the personal computer 18 displays the analysis result on the display device 18b for visualization. The display device 18b includes at least an A scope (basic display: displays echo height on the time axis), a B scope (cross section display: displays the position of the probe 14 and the depth position of the terminal ends 5a and 6a), and the C scope. A display screen based on (planar display: surface display of terminations 5a and 6a) is displayed. Note that these display screens may be displayed together on one screen, or may be selectively displayed by a tester switching.
　例えば、パソコン１８は、ＡＤ／ＤＡ変換ボード１７から受信した電気信号から、探触子１４が超音波を送信してから回折波又は反射波を受信するまでの時間を算出し、算出した時間に、超音波がデフケース１を通過する速度（音速）を乗じることにより、超音波の伝播時間（探触子１４から反射源までの距離）を算出する。そして、パソコン１８は、回折波又は反射波のエコー強度（波形）と、超音波の伝播時間（距離）とを直角座標上に表示したＡスコープを、表示装置１８ｂに表示する。Ａスコープは、解析データの取扱いが容易である。しかし、その波形から溶着金属５，６の終端５ａ，６ａの位置や溶着金属５，６内の欠陥や寸法を判断するには、試験者の熟練した技能を必要とする。 For example, the personal computer 18 calculates the time from when the probe 14 transmits an ultrasonic wave until it receives a diffracted wave or a reflected wave from the electrical signal received from the AD / DA conversion board 17, and at the calculated time. Then, the propagation time of ultrasonic waves (distance from the probe 14 to the reflection source) is calculated by multiplying the speed (sound speed) of ultrasonic waves passing through the differential case 1. Then, the personal computer 18 displays an A scope in which the echo intensity (waveform) of the diffracted wave or the reflected wave and the propagation time (distance) of the ultrasonic wave are displayed on the rectangular coordinates on the display device 18b. The A scope is easy to handle analysis data. However, in order to determine the positions of the ends 5a and 6a of the weld metals 5 and 6 and the defects and dimensions in the weld metals 5 and 6 from the waveform, skill of the tester is required.
　そこで、パソコン１８は、Ａスコープ波形を輝度変調（又は色変調）して線で表し、探触子１４のデフギア４のスキャン位置と超音波伝播時間（深さ（距離））とを直角座標にとったＢスコープを、表示装置１８ｂに表示する。回折波は、反射波と比べてエコー高さの変化率が大きい特性がある。そのため、Ｂスコープの表示画面には、回折波が発生した位置の輝度（色）が、反射波が発生した位置の輝度（色）と相違するように表示される。よって、Ｂスコープの表示画面に表示されるエコー高さ（輝度又は色）から、回折波を発生した溶着金属５の終端５ａの位置（溶接部分７の脚長Ｄ１）が可視化され、試験者によって直観的に把握されるようになる。 Therefore, the personal computer 18 luminance-modulates (or color-modulates) the A scope waveform and expresses it with a line, and the scanning position of the differential gear 4 of the probe 14 and the ultrasonic wave propagation time (depth (distance)) are expressed in rectangular coordinates. The taken B scope is displayed on the display device 18b. A diffracted wave has a characteristic that the rate of change in echo height is larger than that of a reflected wave. Therefore, the B scope display screen displays the luminance (color) at the position where the diffracted wave is generated different from the luminance (color) at the position where the reflected wave is generated. Therefore, the position of the terminal end 5a of the weld metal 5 where the diffracted wave is generated (the leg length D1 of the welded portion 7) is visualized from the echo height (luminance or color) displayed on the display screen of the B scope, and is intuitively viewed by the tester. Will be grasped.
　このとき、パソコン１８は、解析結果から突き合わせ面１ａ，２ａの間を基準とする断面画像を作成し、表示装置１８ｂに表示する。そのため、断面画像から、溶着金属５の全体形状や内部の欠陥などがデフギア４の軸方向に沿って可視化され、試験者によって直観的に把握されるようになる。 At this time, the personal computer 18 creates a cross-sectional image based on the space between the butted surfaces 1a and 2a from the analysis result and displays it on the display device 18b. Therefore, from the cross-sectional image, the overall shape of the weld metal 5 and internal defects are visualized along the axial direction of the differential gear 4 and intuitively grasped by the tester.
　また、パソコン１８は、探触子１４におけるある深さの受信エコー強度を輝度変調（又は色変調）して、デフギア４上における位置に表示したＣスコープを、表示装置１８ｂに表示する。Ｃスコープの表示画面には、Ｂスコープの表示画面と同様に、回折波が発生した位置の輝度（又は色）が、反射が発生した位置の輝度（又は色）と相違するように表示される。よって、溶着金属５の終端５ａの位置（深さ）や溶着金属５の内部に発生した傷の範囲などが可視化される。その結果、試験者がデフギア４の全周方向に沿って溶着金属５の内部に発生した傷の範囲などを直感的に把握できるようになる。 Also, the personal computer 18 performs luminance modulation (or color modulation) on the received echo intensity at a certain depth in the probe 14 and displays the C scope displayed at the position on the differential gear 4 on the display device 18b. Similar to the display screen of the B scope, the luminance (or color) at the position where the diffracted wave is generated is displayed on the C scope display screen so as to be different from the luminance (or color) at the position where the reflection occurs. . Therefore, the position (depth) of the terminal end 5a of the weld metal 5 and the range of scratches generated in the weld metal 5 are visualized. As a result, the tester can intuitively grasp the range of scratches generated in the weld metal 5 along the entire circumferential direction of the differential gear 4.
　よって、本実施形態の溶接構造１０によれば、リングギア２の突き合わせ面２ａとデフケース１の突き合わせ面１ａの間に、探触子１４が送信する超音波の波長より大きい幅Ｂを有する空隙部Ｓ１を設けたことにより、超音波探傷システム１１が、探触子１４から送信された超音波が溶接部分７に反射して回折波を生じたか否かを明確に検出できるようにしたので、リングギア２とデフケース１の溶接部分７の脚長Ｄ１が精度良く検査される。 Therefore, according to the welded structure 10 of the present embodiment, the gap portion having a width B larger than the wavelength of the ultrasonic wave transmitted by the probe 14 between the butted surface 2a of the ring gear 2 and the butted surface 1a of the differential case 1. Since S1 is provided, the ultrasonic flaw detection system 11 can clearly detect whether or not the ultrasonic wave transmitted from the probe 14 is reflected by the welded portion 7 to generate a diffracted wave. The leg length D1 of the welded portion 7 of the gear 2 and the differential case 1 is inspected with high accuracy.
　溶接部分７の脚長検査が終了した後、試験者が、溶接部分８の脚長検査を開始する開始指示をパソコン１８の入力装置１８ａに入力すると、超音波探傷システム１１は、溶接部分８の脚長検査を開始する。
　溶接部分８の脚長検査は、基本的に上述した溶接部分７の脚長検査と同様の原理で行われる。しかし、溶接部分８が溶接部分７より探触子１４から離れているため、探触子１４が溶着金属６の終端６ａに反射して生じた回折波を受信しにくい。そのため、デフケース１における超音波の減衰が少なければ、溶接部分８は、回折波ではなく、反射波を利用して、脚長Ｄ２を検査される。以下、溶接部分７の脚長検査と異なる作用について、説明する。 When the tester inputs a start instruction to start the leg length inspection of the welded portion 8 to the input device 18a of the personal computer 18 after the leg length inspection of the welded portion 7 is completed, the ultrasonic flaw detection system 11 performs the leg length inspection of the welded portion 8. To start.
The leg length inspection of the welded portion 8 is basically performed on the same principle as the leg length inspection of the welded portion 7 described above. However, since the welded portion 8 is further away from the probe 14 than the welded portion 7, it is difficult for the probe 14 to receive the diffracted wave generated by the reflection from the terminal end 6 a of the weld metal 6. Therefore, if the attenuation of the ultrasonic wave in the differential case 1 is small, the welded portion 8 is inspected for the leg length D2 using a reflected wave instead of a diffracted wave. Hereinafter, an operation different from the leg length inspection of the welded portion 7 will be described.
　図６は、デフギア４の裏面側溶接部分８の脚長Ｄ２を検査するイメージを示す図である。
　図６に示すように、探触子１４は、溶着金属６の終端６ａの設計上の位置を含む所定範囲（以下「第２目標位置」という。）へ向けて超音波をパルス状に送信する。この場合に送信される超音波は、溶接部分８が溶接部分７より探触子１４から離れているため、溶接部分７の脚長検査を行う場合と比べ、周波数が多く設定され、波長が短く設定される。つまり、溶接部分８の脚長Ｄ２を検査する場合、溶接部分７の脚長Ｄ１を検査する場合より、超音波探傷システム１１（探触子１４）の最小検出サイズが小さく設定される。超音波の送信と同時に、回転装置１５が回転駆動し、デフギア４を水槽１２内で１回転させる。 FIG. 6 is a view showing an image for inspecting the leg length D2 of the back surface side welded portion 8 of the differential gear 4. As shown in FIG.
As shown in FIG. 6, the probe 14 transmits ultrasonic waves in a pulse shape toward a predetermined range (hereinafter referred to as “second target position”) including the designed position of the end 6 a of the weld metal 6. . The ultrasonic wave transmitted in this case is set to have a higher frequency and a shorter wavelength than when the welded part 7 is inspected for the leg length because the welded part 8 is farther from the probe 14 than the welded part 7. Is done. That is, when the leg length D2 of the welded portion 8 is inspected, the minimum detection size of the ultrasonic flaw detection system 11 (probe 14) is set smaller than when the leg length D1 of the welded portion 7 is inspected. Simultaneously with the transmission of the ultrasonic wave, the rotating device 15 is driven to rotate, and the differential gear 4 is rotated once in the water tank 12.
　溶着金属６の終端６ａは、空隙部Ｓ１に露出している。空隙部Ｓ１は、両端が溶接部分７，８により塞がれて密閉されているため、デフギア４が水浸されても、超音波の伝播効率の低い空気層を形成できる。空隙部Ｓ１の幅は、超音波の波長より大きく設定されている。溶着金属６の終端６ａに送信された超音波は、溶着金属６の裏側へ空隙部Ｓ１を介して回り込み、回折波を生じたとしても、終端６ａから探触子１４までの距離が遠く、回折波がデフケース１を探触子１４へ向かって戻る間に減衰してしまう。一方、終端６ａに反射した反射波は、直接的にデフケース１を介して探触子１４へ向かって進行するため、回折波と比べて減衰しにくい。しかも、溶接部分８の脚長Ｄ２を検査に使用される超音波は、溶接部分７の脚長Ｄ１を検査に使用される超音波より周波数が多く、波長が短くされている。よって、探触子１４は、終端６ａに反射した反射を受信できる。
　尚、溶着金属６のデフケース１に接する部分に超音波が反射して生じる反射波は、空隙部Ｓ１を介して終端６ａに反射する反射波より反射率が高い。一方、空隙部Ｓ１を介して突き合わせ面２ａに超音波が反射して生じる反射波は、空隙部Ｓ１で減衰されるため、空隙部Ｓ１を介して終端６ａに反射する反射する反射波より反射率が低い。このようにして発生する反射波は、探触子１４に受信される。 The end 6a of the weld metal 6 is exposed in the gap S1. Since the gap S1 is sealed with both ends closed by the welded portions 7 and 8, even if the differential gear 4 is submerged, an air layer with low ultrasonic propagation efficiency can be formed. The width of the gap S1 is set larger than the wavelength of the ultrasonic wave. Even if an ultrasonic wave transmitted to the end 6a of the weld metal 6 wraps around the back side of the weld metal 6 via the gap S1 and generates a diffracted wave, the distance from the end 6a to the probe 14 is long and diffracted. The wave attenuates while returning from the differential case 1 toward the probe 14. On the other hand, the reflected wave reflected at the terminal end 6a travels directly toward the probe 14 via the differential case 1, and therefore is less likely to attenuate than the diffracted wave. Moreover, the ultrasonic wave used for the inspection of the leg length D2 of the welded portion 8 has a higher frequency and a shorter wavelength than the ultrasonic wave used for the inspection of the leg length D1 of the welded portion 7. Therefore, the probe 14 can receive the reflection reflected by the terminal end 6a.
Incidentally, the reflected wave generated by the reflection of the ultrasonic wave at the portion of the weld metal 6 in contact with the differential case 1 has a higher reflectance than the reflected wave reflected on the terminal end 6a through the gap S1. On the other hand, the reflected wave generated by the reflection of the ultrasonic wave on the abutting surface 2a via the gap S1 is attenuated by the gap S1, and therefore the reflectance is higher than the reflected wave reflected to the terminal end 6a via the gap S1. Is low. The reflected wave generated in this way is received by the probe 14.
　パソコン１８が、探触子１４が受信した反射波のエコー高さを解析し、その解析結果をＡスコープ、Ｂスコープ、Ｃスコープにより表示装置１８ｂに表示する。この場合、溶着金属６の終端６ａに反射した反射波は、溶着金属６とデフケース１の境界で反射した反射波よりエコー高さが低く、突き合わせ面２ａに反射した反射波よりエコー高さが高い。よって、エコー高さから空隙部Ｓ１の下端部、つまり、溶着金属６の終端６ａが可視化されて、表示装置１８ｂに表示される。 The personal computer 18 analyzes the echo height of the reflected wave received by the probe 14 and displays the analysis result on the display device 18b by the A scope, B scope, and C scope. In this case, the reflected wave reflected on the terminal end 6a of the weld metal 6 has a lower echo height than the reflected wave reflected at the boundary between the weld metal 6 and the differential case 1, and has a higher echo height than the reflected wave reflected on the butt surface 2a. . Therefore, the lower end of the gap S1, that is, the end 6a of the weld metal 6 is visualized from the echo height and displayed on the display device 18b.
　従って、本実施形態の溶接構造１０は、リングギア２の突き合わせ面２ａとデフケース１の突き合わせ面１ａの間に、探触子１４が送信する超音波の波長より大きい幅Ｂを有する空隙部Ｓ１を設けたことにより、超音波探傷システム１１が、探触子１４から送信された超音波が溶着金属６の終端６ａに反射したか否かを明確に検出できるようにしたので、リングギア２とデフケース１の溶接部分８の脚長Ｄ２が精度良く検査される。 Therefore, in the welded structure 10 of the present embodiment, a gap S1 having a width B larger than the wavelength of the ultrasonic wave transmitted by the probe 14 is provided between the butted surface 2a of the ring gear 2 and the butted surface 1a of the differential case 1. Since the ultrasonic flaw detection system 11 can clearly detect whether or not the ultrasonic wave transmitted from the probe 14 is reflected by the terminal end 6a of the weld metal 6, the ring gear 2 and the differential case are provided. The leg length D2 of one welded portion 8 is inspected with high accuracy.
　続いて、溶接部分７，８の脚長Ｄ１，Ｄ２が異なる第１～第３実施例について、超音波探傷システム１１を用いて溶接部分７，８の脚長検査を行った結果について説明する。図７は、第１実施例の断面図である。図８～図１１は、第１実施例の脚長検査結果を表示する画面を示す図である。図１２は、第２実施例の断面図である。図１３～図１６は、第２実施例の脚長検査結果を表示する画面を示す図である。図１７は、第３実施例の断面図である。図１８～図２１は、第３実施例の脚長検査結果を表示する画面を示す図である。 Subsequently, the results of the leg length inspection of the welded portions 7 and 8 using the ultrasonic flaw detection system 11 in the first to third embodiments in which the leg lengths D1 and D2 of the welded portions 7 and 8 are different will be described. FIG. 7 is a cross-sectional view of the first embodiment. 8 to 11 are diagrams showing screens for displaying the leg length inspection results of the first embodiment. FIG. 12 is a cross-sectional view of the second embodiment. 13 to 16 are diagrams showing screens for displaying the leg length inspection results of the second embodiment. FIG. 17 is a cross-sectional view of the third embodiment. 18 to 21 are diagrams showing screens for displaying the leg length inspection results of the third embodiment.
　超音波探傷システム１１は、溶接部分７の脚長検査を行う場合、探触子１４から第１～第３実施例の「第１目標位置」に向かって、周波数５ＭＨｚ、音速３０８０ｍ／ｓ、波長０．６０ｍｍの超音波を、送信する。
　また、探傷システム１１は、溶接部分８の脚長検査を行う場合、探触子１４から第１～第３実施例の「第２目標位置」に向かって、周波数１０ＭＨｚ、音速３０８０ｍ／ｓ、波長０．３１ｍｍの超音波を、送信する。 When performing the leg length inspection of the welded portion 7, the ultrasonic flaw detection system 11 has a frequency of 5 MHz, a sound velocity of 3080 m / s, and a wavelength of 0 from the probe 14 toward the “first target position” of the first to third embodiments. Transmit 60mm ultrasound.
Further, when performing the leg length inspection of the welded portion 8, the flaw detection system 11 has a frequency of 10 MHz, a sound velocity of 3080 m / s, and a wavelength of 0 from the probe 14 toward the “second target position” of the first to third embodiments. .31mm ultrasonic waves are transmitted.
　図７に示す第１実施例と、図１２に示す第２実施例と、図１７に示す第３実施例は、リングギア２とデフケース１が同一形状のデフギアである。デフケース１の突き合わせ面１ａとリングギア２の突き合わせ面２ａの軸方向（図中上面方向）の厚さＥは、２３ｍｍである。空隙部Ｓ１の幅Ｂ（凹溝１ｂの径方向幅寸法Ｂ）は、超音波の波長より大きい０．６ｍｍに設定されている。そして、空隙部Ｓ１の軸方向長さＣ（凹部１ｂの溝幅Ｃ）は、２０ｍｍである。溶接部分７，８の設計上の脚長Ｄ１，Ｄ２は、３．０ｍｍとする。
　第１～第３実施例は、溶接部分７，８の実際の脚長Ｄ１，Ｄ２のみが相違している。 In the first embodiment shown in FIG. 7, the second embodiment shown in FIG. 12, and the third embodiment shown in FIG. 17, the ring gear 2 and the differential case 1 are differential gears having the same shape. A thickness E in the axial direction (upper surface direction in the drawing) of the butting surface 1a of the differential case 1 and the butting surface 2a of the ring gear 2 is 23 mm. The width B of the gap S1 (the radial width dimension B of the concave groove 1b) is set to 0.6 mm, which is larger than the wavelength of the ultrasonic wave. And the axial direction length C (groove width C of the recessed part 1b) of the space | gap part S1 is 20 mm. The designed leg lengths D1 and D2 of the welded portions 7 and 8 are 3.0 mm.
In the first to third embodiments, only the actual leg lengths D1 and D2 of the welded portions 7 and 8 are different.
　本実施例において、「第１目標位置」は、終端５ａの設計上の位置（表面から３．０ｍｍ）の±５．０ｍｍの範囲（デフケース１の表面から０ｍｍ以上８．０ｍｍ以下の範囲）とする。また、本実施例において、「第２目標位置」は、終端６ａの設計上の位置（裏面から３．０ｍｍ）の±５．０ｍｍの範囲（デフケース１の表面から１５．０ｍｍ以上２３．０ｍｍの範囲）とする。 In this embodiment, the “first target position” is a range of ± 5.0 mm (a range of 0 mm or more and 8.0 mm or less from the surface of the differential case 1) of the design position (3.0 mm from the surface) of the terminal end 5a. To do. In the present embodiment, the “second target position” is within a range of ± 5.0 mm of the designed position of the terminal end 6a (3.0 mm from the back surface) (15.0 mm or more and 23.0 mm from the surface of the differential case 1). Range).
＜第１実施例の脚長検査結果について＞
　超音波探傷システム１１は、第１実施例の表面から溶接部分７の「第１目標位置」に超音波を送信して脚長検査を行ったところ、図８の矢印に示すように、Ｂスコープの表示画面には、デフケース１の表面（０ｍｍの位置）から３．０ｍｍの深さの位置の輝度（色）が、他の部分と区別して表示された。また、図９の断面表示画面には、ドットハッチングで示された溶着金属５の終端５ａが、空隙部Ｓ１内へ下向きに突出する様子と、溶着金属５内に傷がない様子が表示された。 <About the leg length test result of the first embodiment>
The ultrasonic flaw detection system 11 transmits an ultrasonic wave from the surface of the first embodiment to the “first target position” of the welded portion 7 and performs leg length inspection. As shown by the arrow in FIG. On the display screen, the luminance (color) at a position of a depth of 3.0 mm from the surface of the differential case 1 (position of 0 mm) was displayed separately from other portions. In addition, on the cross-section display screen of FIG. 9, it is displayed that the terminal end 5a of the weld metal 5 indicated by dot hatching protrudes downward into the gap S1 and the weld metal 5 is not damaged. .
　その後、超音波探傷システム１１は、第１実施例の裏面から溶接部分８の「第２目標位置」に超音波を送信して脚長検査を行ったところ、図１０の矢印に示すように、Ｂスコープの表示画面には、デフケース１の表面から２０．０ｍｍの深さの位置の輝度（色）が、他の部分と区別して表示された。また、図１１の断面表示画面には、ドットハッチングで示された溶着金属６の終端６ａが、空隙部Ｓ１内へ上向きに突出する様子と、溶着金属６内に傷がない様子が表示された。 Thereafter, the ultrasonic flaw detection system 11 transmits ultrasonic waves from the back surface of the first embodiment to the “second target position” of the welded portion 8 to perform leg length inspection. As shown by the arrow in FIG. On the display screen of the scope, the brightness (color) at a depth of 20.0 mm from the surface of the differential case 1 was displayed separately from other parts. In addition, on the cross-section display screen of FIG. 11, it is displayed that the terminal end 6a of the weld metal 6 indicated by dot hatching protrudes upward into the gap portion S1 and that the weld metal 6 is not damaged. .
　上記脚長検査後に、試験者が、図７に示すように、超音波を送信した部分に沿って第１実施例を切断し、溶接部分７，８の脚長Ｄ１，Ｄ２を実測したところ、それぞれ３．０ｍｍであった。また、試験者は、溶着金属５，６内に傷を発見しなかった。 After the leg length inspection, as shown in FIG. 7, the tester cuts the first embodiment along the portion where the ultrasonic wave was transmitted and measured the leg lengths D1 and D2 of the welded portions 7 and 8, respectively. 0.0 mm. Further, the tester did not find any scratches in the weld metals 5 and 6.
＜第２実施例の脚長検査結果について＞
　超音波探傷システム１１は、第２実施例の表面から溶接部分７の「第１目標位置」に超音波を送信して脚長検査を行ったところ、図１３の矢印に示すように、Ｂスコープの表示画面には、デフケース１の表面から２．０ｍｍの深さの位置の輝度（色）が、他の部分と区別して表示された。また、図１４の断面表示画面には、ドットハッチングで示された溶着金属５の終端５ａが、空隙部Ｓ１内へ突出する量が少ない様子と、溶着金属５内に傷がない様子が表示された。 <About the leg length test result of the second embodiment>
The ultrasonic flaw detection system 11 transmits an ultrasonic wave from the surface of the second embodiment to the “first target position” of the welded portion 7 and performs leg length inspection. As shown by the arrow in FIG. On the display screen, the luminance (color) at a depth of 2.0 mm from the surface of the differential case 1 was displayed separately from the other portions. In addition, on the cross-section display screen of FIG. 14, it is displayed that the end 5a of the weld metal 5 indicated by dot hatching has a small amount protruding into the gap S1 and that the weld metal 5 is not damaged. It was.
　その後、超音波探傷システム１１は、第２実施例の裏面から溶接部分８の「第２目標位置」に超音波を送信して脚長検査を行ったところ、図１５の矢印に示すように、Ｂスコープの表示画面には、デフケース１の表面から２１．０ｍｍの深さの位置の輝度（色）が、他の部分と区別して表示された。また、図１６の断面表示画面には、ドットハッチングで表示された溶着金属６の終端６ａが、空隙部Ｓ１内へ突出する量が少ない様子と、溶着金属６内に傷がない様子が表示された。 Thereafter, the ultrasonic flaw detection system 11 transmits ultrasonic waves from the back surface of the second embodiment to the “second target position” of the welded portion 8 to perform leg length inspection. As shown by the arrow in FIG. On the display screen of the scope, the brightness (color) at a position 21.0 mm deep from the surface of the differential case 1 was displayed separately from other parts. In addition, on the cross-section display screen of FIG. 16, it is displayed that the end 6a of the weld metal 6 displayed by dot hatching has a small amount protruding into the gap S1 and that the weld metal 6 is not damaged. It was.
　上記脚長検査後に、試験者が、図１２に示すように、超音波を送信した部分に沿って第２実施例を切断し、溶接部分７，８の脚長Ｄ１，Ｄ２を実測したところ、それぞれ２．０ｍｍであった。また、試験者は、溶着金属５，６の内部に傷を発見しなかった。 After the leg length inspection, as shown in FIG. 12, the tester cut the second embodiment along the portion where the ultrasonic wave was transmitted and measured the leg lengths D1 and D2 of the welded portions 7 and 8, respectively. 0.0 mm. Further, the tester did not find any scratches inside the weld metals 5 and 6.
＜第３実施例の脚長検査結果について＞
　超音波探傷システム１１は、第３実施例の表面から溶接部分７の「第１目標位置」に超音波を送信して脚長検査を行ったところ、図１８の矢印に示すように、Ｂスコープの表示画面には、デフケース１の表面から５．０ｍｍの深さの位置の輝度（色）が、他の部分と区別して表示された。また、図１９の断面表示画面には、ドットハッチングで示された溶着金属５の終端５ａが、空隙部Ｓ１へ大きく突出している様子と、溶着金属５に複数の傷がある様子が表示された。 <About the leg length test result of the third embodiment>
The ultrasonic flaw detection system 11 transmits an ultrasonic wave from the surface of the third embodiment to the “first target position” of the welded portion 7 and performs a leg length inspection. As shown by an arrow in FIG. On the display screen, the luminance (color) at a depth of 5.0 mm from the surface of the differential case 1 is displayed separately from the other portions. In addition, on the cross-section display screen of FIG. 19, it is displayed that the terminal end 5a of the weld metal 5 indicated by dot hatching protrudes greatly into the gap S1 and the weld metal 5 has a plurality of scratches. .
　その後、超音波探傷システム１１は、第３実施例の裏面から溶接部分８の「第２目標位置」に超音波を送信して脚長検査を行ったところ、図２０の矢印に示すように、Ｂスコープの表示画面には、デフケース１の表面から１８．０ｍｍの深さの位置の輝度（色）が、他の部分と区別して表示された。また、図２１の断面表示画面には、ドットハッチングで示された溶着金属６の終端６ａが空隙部Ｓ１に大きく突出している様子と、溶着金属６内に２個の傷がある様子が表示された。 After that, the ultrasonic flaw detection system 11 conducted the leg length inspection by transmitting ultrasonic waves from the back surface of the third embodiment to the “second target position” of the welded portion 8, as shown by the arrow in FIG. On the display screen of the scope, the luminance (color) at a position 18.0 mm deep from the surface of the differential case 1 was displayed separately from other parts. In addition, on the cross-section display screen of FIG. 21, a state in which the end 6a of the weld metal 6 indicated by dot hatching greatly protrudes into the gap S1 and a state in which there are two scratches in the weld metal 6 are displayed. It was.
　上記脚長検査後に、試験者が、図１７に示すように、超音波を送信した部分に沿って第３実施例を切断し、溶着部分７，８の脚長Ｄ１，Ｄ２を実測したところ、それぞれ５．０ｍｍであった。そして、試験者は、溶着金属５の内部に細かい傷５ｂを発見し、溶着金属６の内部に２個の傷６ｂを発見した。 After the leg length inspection, as shown in FIG. 17, the tester cuts the third embodiment along the portion where the ultrasonic wave was transmitted and measured the leg lengths D1 and D2 of the welded portions 7 and 8, respectively. 0.0 mm. Then, the tester found a fine flaw 5 b inside the weld metal 5 and found two flaws 6 b inside the weld metal 6.
＜実施例のまとめ＞
　上記脚長検査結果より、第１～第３実施例の表示装置１８ｂに表示される脚長検査結果と、第１～第３実施例に形成された溶接部分７，８の実際の脚長Ｄ１，Ｄ２が対応しており、上記実施形態の溶接構造１０によれば、溶接部分７，８の脚長Ｄ１，Ｄ２を精度良く検査できることが、実証された。また、溶着金属５，６の内部に発生したブローホールなどの傷も、発見できることが実証された。 <Summary of Examples>
From the leg length inspection results, the leg length inspection results displayed on the display device 18b of the first to third embodiments and the actual leg lengths D1 and D2 of the welded portions 7 and 8 formed in the first to third embodiments are as follows. Correspondingly, according to the welded structure 10 of the above embodiment, it was proved that the leg lengths D1 and D2 of the welded portions 7 and 8 can be inspected with high accuracy. In addition, it was proved that scratches such as blow holes generated in the weld metals 5 and 6 could be found.
　本発明は、上記実施形態に限定されることなく、色々な応用が可能である。
（１）例えば、上記実施形態では、探触子１４を固定し、デフギア４を回転させた。これに対して、デフギア４を水中で固定し、探触子１４を移動させることにより、超音波をデフギア４の溶接部分７，８に送信するようにしても良い。また、デフギア４を回転させながら、探触子１４をスライドさせることにより、溶接部分７，８の脚長検査を行っても良い。
（２）例えば、上記実施形態では、デフギア４と探触子１４を水没させた状態で、溶接部分７，８の脚長検査を実施した。これに対して、デフギア４の表面にゼリーを塗り、ゼリー上で探触子１４を移動させることにより、溶接部分７，８の脚長検査を行っても良い。
（３）例えば、上記実施形態では、１個の凹溝１ｂにより空隙部Ｓ１を設けた。これに対して、溶着金属５，６の終端５ａ，６ａの設計上の位置に相当する部分に凹溝１ｂをそれぞれ設け、突き合わせ面１ａ，２ａの間に２個の空隙部Ｓ１を設けても良い。
（４）例えば、上記実施形態では、デフケース１の突き合わせ面１ａに凹溝１ｂを形成した。これに対して、リングギア２の突き合わせ面２ａに凹溝を形成し、デフケース１の好き合わせ面１ａを平坦に形成することにより、空隙部Ｓ１を設けてもよい。また、突き合わせ面１ａ，２ａの両方に凹溝を形成し、突き合わせ面１ａ，２ａの間に空隙部Ｓ１を形成しても良い。
（５）例えば、超音波探傷システム１１は、探触子１４の波長や入射角度を変えることにより、リングギア２やデフケース１のワーク寸法の変化に対応して脚長Ｄ１，Ｄ２を測定することができる。 The present invention is not limited to the above embodiment, and various applications are possible.
(1) For example, in the above embodiment, the probe 14 is fixed and the differential gear 4 is rotated. On the other hand, ultrasonic waves may be transmitted to the welded portions 7 and 8 of the differential gear 4 by fixing the differential gear 4 in water and moving the probe 14. Further, the leg length inspection of the welded portions 7 and 8 may be performed by sliding the probe 14 while rotating the differential gear 4.
(2) For example, in the said embodiment, the leg length inspection of the welding parts 7 and 8 was implemented in the state where the differential gear 4 and the probe 14 were submerged. On the other hand, the leg length inspection of the welded portions 7 and 8 may be performed by applying jelly on the surface of the differential gear 4 and moving the probe 14 on the jelly.
(3) For example, in the above embodiment, the gap portion S1 is provided by one concave groove 1b. On the other hand, even if the concave grooves 1b are provided in the portions corresponding to the design positions of the terminal ends 5a and 6a of the weld metals 5 and 6, respectively, and the two gaps S1 are provided between the butted surfaces 1a and 2a. good.
(4) For example, in the above embodiment, the concave groove 1 b is formed in the abutting surface 1 a of the differential case 1. On the other hand, the gap S1 may be provided by forming a concave groove on the abutting surface 2a of the ring gear 2 and forming the favorite surface 1a of the differential case 1 flat. Moreover, a ditch | groove may be formed in both the abutting surfaces 1a and 2a, and the space | gap part S1 may be formed between the abutting surfaces 1a and 2a.
(5) For example, the ultrasonic flaw detection system 11 can measure the leg lengths D <b> 1 and D <b> 2 corresponding to changes in the workpiece dimensions of the ring gear 2 and the differential case 1 by changing the wavelength and incident angle of the probe 14. it can.

Claims (2)

  1. 　デフケースの第１突き合わせ面とリングギアの第２突き合わせ面とが突き合わされ、突き合わされた部分の端部が溶着金属により溶接されており、前記溶着金属により溶接された溶接部分に超音波を照射され、反射源から反射するエコーを解析することにより前記溶接部分の長さが検査される溶接構造において、
    　前記第１突き合わせ面と前記第２突き合わせ面との間に、前記超音波の波長より大きい幅の空隙部が形成されており、
    　前記空隙部は、前記第１突き合わせ面又は前記第２突き合わせ面の少なくとも一方に形成された凹溝により形成され、
    　前記溶着金属の終端が前記空隙部に露出している
    ことを特徴とする溶接構造。     The first butting surface of the differential case and the second butting surface of the ring gear are butted, and the end of the butted portion is welded with a weld metal, and the welded portion welded with the weld metal is irradiated with ultrasonic waves. In the welded structure, the length of the welded portion is inspected by analyzing the echo reflected from the reflection source,
    A gap having a width larger than the wavelength of the ultrasonic wave is formed between the first butted surface and the second butted surface,
    The gap is formed by a groove formed in at least one of the first butted surface or the second butted surface,
    The welding structure characterized in that the end of the weld metal is exposed in the gap.
  2. 　請求項１に記載する溶接構造において、
    　前記第１及び前記第２突き合わせ面が環状に設けられ、
    　前記溶接部分は、前記第１及び前記第２突き合わせ面の一端から溶接された第１溶接部分と、前記第１及び前記第２突き合わせ面の他端から溶接された第２溶接部分とを含み、
    　前記第１及び第２溶接部分が前記空隙部に露出している
    ことを特徴とする溶接構造。
          In the welded structure according to claim 1,
    The first and second butting surfaces are provided in an annular shape,
    The welded portion includes a first welded portion welded from one end of the first and second butted surfaces, and a second welded portion welded from the other end of the first and second butted surfaces,
    The welding structure, wherein the first and second welded portions are exposed in the gap.
PCT/JP2010/060128 2010-06-15 2010-06-15 Structure for welding ring gear and differential case WO2011158330A1 (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102692451A (en) * 2012-05-21 2012-09-26 江苏常牵庞巴迪牵引***有限公司 Rotor end ring brazing quality detection process
JP2015516082A (en) * 2012-05-11 2015-06-04 ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ Method for detecting hollow shaft damage
JP2016061760A (en) * 2014-09-22 2016-04-25 富士重工業株式会社 Ultrasonic flaw detection device and ultrasonic flaw detection method
CN107695320A (en) * 2016-08-08 2018-02-16 株式会社斯巴鲁 The manufacture method and differential gear of differential gear
JP2020523201A (en) * 2018-03-30 2020-08-06 重慶聯豪科技有限公司Ｃｈｏｎｇｑｉｎｇ Ｌｉａｎｈａｏ Ｔｅｃｈｎｏｌｏｇｙ Ｃｏ．，Ｌｔｄ． Welding process of differential assembly
TWI739702B (en) * 2020-12-31 2021-09-11 群光電能科技股份有限公司 Welding structures on two objects for connection
US11353100B2 (en) * 2018-11-22 2022-06-07 Audi Ag Differential gear for a motor vehicle

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS514736A (en) * 1974-06-29 1976-01-16 Toyota Motor Co Ltd DEIFUARENSHARUGYAKEESUHENO RINGUGYANO TORITSUKE KOZO
JPS5575888A (en) * 1978-11-30 1980-06-07 Nissan Motor Co Ltd Welded structure of sintered metal
JPS6162663A (en) * 1984-09-03 1986-03-31 Toyoda Autom Loom Works Ltd Power transmission gear composed of large and small gears
JPH0314066U (en) * 1989-06-27 1991-02-13
JP2001153009A (en) * 1999-09-30 2001-06-05 Defontaine:Sa System of linking toothed starter ring to supporting body connected to output shaft of internal combustion engine

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS514736A (en) * 1974-06-29 1976-01-16 Toyota Motor Co Ltd DEIFUARENSHARUGYAKEESUHENO RINGUGYANO TORITSUKE KOZO
JPS5575888A (en) * 1978-11-30 1980-06-07 Nissan Motor Co Ltd Welded structure of sintered metal
JPS6162663A (en) * 1984-09-03 1986-03-31 Toyoda Autom Loom Works Ltd Power transmission gear composed of large and small gears
JPH0314066U (en) * 1989-06-27 1991-02-13
JP2001153009A (en) * 1999-09-30 2001-06-05 Defontaine:Sa System of linking toothed starter ring to supporting body connected to output shaft of internal combustion engine

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015516082A (en) * 2012-05-11 2015-06-04 ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ Method for detecting hollow shaft damage
CN102692451A (en) * 2012-05-21 2012-09-26 江苏常牵庞巴迪牵引***有限公司 Rotor end ring brazing quality detection process
JP2016061760A (en) * 2014-09-22 2016-04-25 富士重工業株式会社 Ultrasonic flaw detection device and ultrasonic flaw detection method
US9594001B2 (en) 2014-09-22 2017-03-14 Fuji Jukogyo Kabushiki Kaisha Ultrasonic testing device and ultrasonic testing method
CN107695320A (en) * 2016-08-08 2018-02-16 株式会社斯巴鲁 The manufacture method and differential gear of differential gear
CN107695320B (en) * 2016-08-08 2019-04-12 株式会社斯巴鲁 The manufacturing method and differential gear of differential gear
JP2020523201A (en) * 2018-03-30 2020-08-06 重慶聯豪科技有限公司Ｃｈｏｎｇｑｉｎｇ Ｌｉａｎｈａｏ Ｔｅｃｈｎｏｌｏｇｙ Ｃｏ．，Ｌｔｄ． Welding process of differential assembly
US11353100B2 (en) * 2018-11-22 2022-06-07 Audi Ag Differential gear for a motor vehicle
TWI739702B (en) * 2020-12-31 2021-09-11 群光電能科技股份有限公司 Welding structures on two objects for connection
US12006967B2 (en) 2020-12-31 2024-06-11 Chicony Power Technology Co., Ltd. Welding structure for connection of two objects

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