Travel device

Abstract

To provide a travel device which can move from a horizontal surface to a vertical surface without stopping.SOLUTION: A travel device 1 travels on a surface of an object to be inspected (an inspected object) for a non-destructive examination of the inspected object including a magnetic material and includes: a vehicle body 11; an inspection unit 12 mounted on the vehicle body; a front wheel 13F and a rear wheel 13R rotatably provided at the vehicle body; motors 14L, 14R which drive the front wheel and the rear wheel; and a magnet provided in at least the front wheel. The front wheel has a diameter larger than that of the rear wheel.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a traveling device, and more particularly to a traveling device that travels on the surface of an inspection object including a magnetic body for non-destructive inspection of the inspection object. [Background technology]

[0002] Non-destructive testing is widely known to detect defects such as scratches and corrosion on the surface and / or inside of a steel structure without destroying the structure. In this non-destructive testing, a traveling device is moved over the surface of the object to be inspected, and an inspection unit mounted on the traveling device detects defects.

[0003] As a traveling device, a self-propelled traveling device in which wheels provided on a vehicle body are driven by a motor is known. It is also known to provide a magnet on the traveling device in order to attract the traveling device to the inspection object (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-204560 A Summary of the Invention [Problem to be solved by the invention]

[0005] There is a demand for a traveling device to be able to move onto a vertical surface that rises vertically from a horizontal surface without stopping. However, in general, the moment the traveling device traveling on the horizontal surface collides with the vertical surface, the traveling device stops without being able to climb up the vertical surface.

[0006] The present disclosure has been made in consideration of the above circumstances, and has an object to provide a traveling device that allows a user to move from a horizontal surface to a vertical surface without stopping. [Means for solving the problem]

[0007] According to one aspect of the present disclosure, A traveling device that travels on a surface of an object to be inspected, the surface being subjected to non-destructive inspection of the object, the traveling device comprising: The car body and An inspection unit mounted on the vehicle body; Front and rear wheels rotatably mounted on the vehicle body; A motor that drives the front wheels and the rear wheels; A magnet provided on at least the front wheel; Equipped with The front wheels have a larger diameter than the rear wheels. A traveling device characterized by the above features is provided.

[0008] Preferably, the adhesive force of the front wheels to the surface of the object to be inspected is stronger than the adhesive force of the rear wheels.

[0009] Preferably, the magnets are provided on the front wheels and the rear wheels, The magnets in the front wheels have a stronger magnetic force than the magnets in the rear wheels.

[0010] Preferably, the front wheels and the rear wheels are provided with ring-shaped magnets, The magnets of the front wheels have a larger diameter than the magnets of the rear wheels.

[0011] Preferably, the running device includes a free wheel positioned above the front wheel.

[0012] Preferably, the inspection unit comprises: a probe for contacting a surface of the object to be inspected; a lift mechanism for raising and lowering the probe; Equipped with.

[0013] Preferably, the running device is When the object to be inspected, which is perpendicular in a side view, is sandwiched between the front and rear wheels from below, no part other than the front and rear wheels is configured to come into contact with the object to be inspected.

[0014] Preferably, the inspection object has a horizontal surface and a vertical surface rising perpendicularly from the horizontal surface, When the front and rear wheels of the running device are grounded on the horizontal surface and the front end of the front wheel of the running device abuts the vertical surface, the intersection point where an imaginary straight line passing through the center of rotation of the front wheel and the center of rotation of the rear wheel intersects with the vertical surface is positioned above the point of abutment between the front wheel and the vertical surface. Effect of the Invention

[0015] According to the present disclosure, a traveling device can be provided that can transfer from a horizontal surface to a vertical surface without stopping. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram showing an inspection device. [Diagram 2] FIG. 4 is a left side view showing the traveling device in a reference state. [Diagram 3] FIG. 4 is a front view showing the traveling device in a reference state. [Figure 4] FIG. 4 is a partial rear view showing the traveling device in a reference state. [Diagram 5] FIG. 4 is a left side view showing the traveling device in use. [Figure 6] FIG. [Figure 7] FIG. 4 is a left side view showing the traveling device in a reference state with the wheel drive system omitted. [Figure 8] FIG. 2 is a front view showing a cross section of a wheel drive system in a traveling device in a reference state. [Figure 9] FIG. 4 is a bottom cross-sectional view showing the left wheel drive system in the traveling device in a reference state. [Figure 10] FIG. 4 is a bottom view showing a portion where a motor is mounted in the traveling device in a reference state. [Figure 11] A typical example of a servo motor is shown, where (A) is a side view, (B) is a plan view, and (C) is a rear view. [Figure 12]FIG. 11 is a schematic diagram showing the operation of a comparative example. [Figure 13] 5 is a schematic diagram showing the operation of the present embodiment. FIG. [Figure 14] FIG. 11 is a schematic diagram showing the operation of a comparative example. [Figure 15] 5 is a schematic diagram showing the operation of the present embodiment. FIG. [Figure 16] 5 is a schematic diagram showing the operation of the present embodiment. FIG. [Figure 17] 5 is a schematic diagram showing the operation of the present embodiment. FIG. [Figure 18] 5 is a schematic diagram showing an operation during reverse driving in this embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the following embodiments.

[0018] Fig. 1 is a schematic diagram showing the whole of an inspection device for performing non-destructive inspection of an object to be inspected. The object to be inspected P includes a magnetic material or is formed of a magnetic material. Specifically, the object to be inspected P is a steel structure made of steel, such as a bridge, scaffolding, gondola, piping, furnace wall, chimney, etc.

[0019] The inspection device comprises a traveling device 1 that travels on the surface of the object to be inspected P, a control device 2 that receives data from an inspection unit mounted on the traveling device 1 and outputs power and control signals to the traveling device 1, a display 3 that displays an image based on the data sent to the control device 2, and a controller 4 that is connected to the control device 2 and operated by an operator S to operate the traveling device 1.

[0020] In this embodiment, the inspection device is configured to perform visual inspection and ultrasonic flaw detection. As will be described in detail later, the inspection unit of the traveling device 1 includes a camera that captures the view in front of the traveling device 1, and an ultrasonic probe that contacts the surface of the inspection object P to transmit and receive ultrasonic waves. The camera is configured by a CCD camera. The image or video data captured by the camera is sent to the control device 2, which displays the image captured by the camera on the display 3. The worker S visually inspects the surface condition of the inspection object P while looking at this image, and also operates the controller 4 to make the traveling device 1 travel along a desired route.

[0021] The inspection unit includes a lift mechanism for raising and lowering the probe. By controlling this lift mechanism, the probe is usually raised and kept above the surface, and only when necessary, the probe is lowered to contact the surface for ultrasonic testing.

[0022] The traveling device 1 is self-propelled, and travels by its wheels being driven by a motor. The traveling device 1 is also attracted to the surface of the inspection object P by a magnet. The traveling device 1 is not equipped with a battery, and travels by obtaining power from an external power supply from the control device 2 via a cable CB. Therefore, since the traveling device 1 is not equipped with a battery, it can be made lighter, and it can be attracted to and travel without any problems even in a difficult position, such as upside down.

[0023] Alternatively, the inspection device may be configured to perform other types of tests, for example the well-known eddy current tests, and the inspection unit may also be suitable for other types of tests, for example a test coil suitable for eddy current tests. The inspection may be performed on any surface of the object P.

[0024] Next, the configuration of the traveling device 1 will be described.

[0025] 2 to 4 are respectively a left side view, a front view, and a partial rear view showing the traveling device 1 in a reference state. Also, Figs. 5 and 6 are respectively a left side view and a rear view showing the traveling device 1 in a use state. The reference state refers to the state at the time of design, and the use state refers to the state during actual use. When the traveling device 1 in the reference state is tilted backward and the front and rear wheels are placed on the ground, it is in the use state.

[0026] For the sake of convenience, the surface of the inspection object P on which the traveling device 1 travels will be referred to as a traveling surface or a road surface. The front-rear, left-right, top-bottom directions of the traveling device 1 in the reference state and in the usage state are as shown in the drawings.

[0027] 2 to 4, the traveling device 1 includes a vehicle body 11, an inspection unit 12 mounted on the vehicle body 11, front wheels 13F and rear wheels 13R (collectively referred to as wheels 13) rotatably provided on the vehicle body 11, motors 14L, 14R (collectively referred to as motors 14) that drive the front wheels 13F and rear wheels 13R, and magnets provided on the front wheels 13F and rear wheels 13R. The traveling device 1 of this embodiment is particularly characterized in that the front wheels 13F have a larger diameter than the rear wheels 13R.

[0028] As shown in detail in Figs. 7 and 8, the vehicle body 11 is constructed by assembling resin parts so as to be as small and lightweight as possible. The vehicle body 11 has a U-shaped lower frame 15 with an open bottom when viewed from the front and rear, and a generally flat upper frame 16 that is attached to the upper surface of the lower frame 15 with a gap therebetween. Legs 17 extending downward are integrally provided at the front and rear ends of the upper frame 16 and also serve as mounting portions for the motor 14. These legs 17 are attached to the lower frame 15 by bolts 18, thereby integrating the lower frame 15 and the upper frame 16. The bolts 18 are hexagon socket extra low head bolts. Most of the other bolts are similar.

[0029] A pair of left and right camera mounts 19 are integrally provided to stand on the front end of the upper frame 16. The upper surfaces of the lower frame 15 and the upper frame 16 are parallel to each other, and in a standard state, they are parallel in the front-rear and left-right directions, i.e., horizontal, but in a used state, they are inclined downward toward the rear (i.e., tilted backward).

[0030] The inspection unit 12 includes a camera 20 that captures the view in front of the traveling device 1. The camera 20 is configured as a CCD camera. The orientation of the camera 20 in the vertical direction can be changed by a servo motor 22.

[0031] The servo motor used in the movable part of this embodiment is a servo motor used mainly in the fields of robots and radio-controlled cars. A representative example is shown in FIG. 11. The servo motor 201 has a case 202 that houses a motor, a gear mechanism, an electric circuit, and the like. The case 202 is a rectangular parallelepiped shape having a length L, a width W, and a height H, with the width W being the shortest of the three. An output shaft 203 protrudes upward in the height H direction from the case 202 at a position biased toward one end side in the length L direction (the right side of (A) and (B), referred to as the output shaft side). For example, a servo horn 204 is attached to this output shaft 203 with a screw (not shown). Mounting tabs or ears 205 are integrally provided at both ends of the case 202 in the length L direction so as to protrude. At least one hole 206 is provided in the ear 205, and two holes 206 are provided in the illustrated example. For convenience, assuming that the output shaft side is the front, case 202 has a front surface 207 , a rear surface 208 , a left side surface 209 , a right side surface 210 , a top surface 211 and a bottom surface 212 .

[0032] As shown in Figs. 4 and 7, the camera 20 is attached to the right side surface of the body 23 of the servo motor 22 via a resin attachment 21. A servo horn 24 attached to the output shaft of the servo motor 22 is inserted into and fixed in a groove 25 of the left camera mount 19. Therefore, when the output shaft of the servo motor 22 rotates, the body 23 rotates relative to the fixed servo horn 23, and the vertical orientation of the camera 20 is changed. A spacer 21A for maintaining the distance between the body 23 and the right camera mount 19 is integrally provided on the attachment 21. A bolt 21B fixed to the right camera mount 19 is inserted into a hole 26 of the spacer 24, and the attachment 21 is supported by the bolt 25 so as to be rotatable coaxially with the output shaft of the servo motor 22.

[0033] In this way, the inspection unit 12 has a changing mechanism for changing the up-down direction of the camera 20. The camera 20 is rotatable about a left-right axis C1 (meaning an axis parallel to the left-right direction) which is coaxial with the output shaft of the servo motor 22.

[0034] 2, 4 and 5, the inspection unit 12 has a probe 27 for contacting the surface of the inspection object P, and a lift mechanism 28 for raising and lowering the probe 27. The probe 27 in this embodiment is an ultrasonic probe for ultrasonic flaw detection testing.

[0035] The lift mechanism 28 has a servo motor 29 attached to the vehicle body 11, a servo horn 30 attached to the output shaft of the servo motor 29, a probe holder 31 that holds the probe 27, and an arm 32 that connects the servo horn 30 and the probe holder 31.

[0036] The servo motor 29 is attached on the lower frame 15 and adjacent to the rear end face of the upper frame 16, with its rear surface facing upward, its top surface facing right, and its output shaft positioned below and coaxial with the left-right axis C2. A hook-shaped fixing piece 33 for fitting and fixing the servo motor 29 extends integrally from the upper frame 16 toward the rear. The upper ear of the servo motor 29 fitted into this fixing piece 33 is fixed to the fixing piece 33 by a screw 34. Note that the more common round head screw or pan head screw is used as the screw for attaching the servo motor. The lower ear is cut away.

[0037] At least a part of the arm 32 is formed of a leaf spring. When the output shaft of the servo motor 29 is rotated, the arm 32 is rotated accordingly, and the probe 27 is raised and lowered. In Figures 2 and 5, the state when the probe 27 is in the normal raised position a is shown by a solid line.

[0038] The state of the probe 27 when it is in the lowered position b during inspection is shown by a solid line in Fig. 4 and by a virtual line in Fig. 5. At this time, the probe 2 is lightly pressed against the surface of the inspection object P. The leaf spring of the arm 32 absorbs the reaction force from the probe 2 like a suspension, and keeps the pressing force of the probe 2 against the surface at an appropriate level. During inspection, the traveling device 1 is temporarily stopped and the probe 27 is lowered to the lowered position b, and when the inspection is completed, the probe 27 is raised to the raised position a and the traveling device 1 returns to traveling again.

[0039] The traveling device 1 has left and right front wheels 13F (13FL, 13FR) and rear wheels 13R (13RL, 13RR), totaling four wheels 13. Hereinafter, as necessary, the left-side components are given the suffix L, and the right-side components are given the suffix R. These four wheels 13 are all driving wheels, and the traveling device 1 is configured as a four-wheel drive vehicle or an all-wheel drive vehicle. However, the number of wheels may be increased or decreased as necessary.

[0040] The left-right axis C3 is the center of rotation of the left and right front wheels 13F, and the left-right axis C4 is the center of rotation of the left and right rear wheels 13R.

[0041] The drive system of the traveling device 1 is configured to be generally symmetrical on the left and right sides, so the configuration on the left side will be mainly described here with reference to Fig. 9, and details of the configuration on the right side will be omitted.

[0042] FIG. 9 is a bottom cross-sectional view of the left wheel attachment portion of the traveling device 1 as viewed from below, and in particular is a cross-sectional view taken along line IX-IX of FIG.

[0043] The lower frame 15 has an upper surface portion 15A and left and right side wall portions 15B (only the left side is shown) that stand vertically down from the left and right edge portions of the upper surface portion 15A (see FIG. 7). The front wheel 13F (13FL) and the rear wheel 13R (13RL) are rotatably attached to the side wall portions 15B.

[0044] First, the mounting structure of the front wheel 13F will be described. The front wheel support member 35 is mounted on the side wall portion 15B of the lower frame 15. The front wheel support member 35 has a flange plate 36 and a support shaft 37 integrally formed therewith. Bolt insertion holes 38 are provided in the flange plate 36 in front of and behind the support shaft 37. As shown in FIG. 7, the side wall portion 15B is provided with a shaft hole 39 and female threaded holes 40 positioned in front of and behind the shaft hole 39. The support shaft 37 is inserted into the shaft hole 39 from the inside of the side wall portion 15B (inside in the vehicle width direction, lower side in FIG. 9), and the flange plate 36 is overlapped with the inner surface of the side wall portion 15B. The bolt 41 is inserted into the bolt insertion hole 38 from the inside, and then tightened into the female threaded hole 40. In this way, the front wheel support member 35 is mounted on the side wall portion 15B. The bolt 41 is a hexagon socket extra low head bolt similar to the above.

[0045] A plastic front wheel 43 is rotatably attached to reduced diameter portion 37A of support shaft 37 located on the outer side of side wall portion 15B (outer side in the vehicle width direction, upper side in Fig. 9) via a pair of flanged ball bearings 42. A stopper ring 44 for preventing ball bearing 42 from coming off is fixed to the outer end face of support shaft 37 with a screw (flat head screw) 45.

[0046] A spur gear 46 is attached to the inner side surface of the wheel 43 in an overlapping manner. A nut 48 is press-fitted and fixed into the inner end of a bolt insertion hole 47 in the wheel 43, and a bolt insertion hole 49 is provided in the spur gear 46. A bolt 50 is inserted into the bolt insertion hole 49 from the inside and then tightened by the nut 48. This fixes the spur gear 46 to the wheel 43. The bolt 50 is a hexagon socket extra low head bolt similar to that described above.

[0047] The spur gear 46 has four mounting portions provided at equal intervals in the circumferential direction.

[0048] A ring-shaped magnet fitting groove 51 is provided around the entire circumference of the outer periphery of wheel 43. A circular ring-shaped magnet, i.e., front wheel magnet 52F (52FL), is fitted into this magnet fitting groove 51.

[0049] A rubber tire 53 is placed on the wheel 43. Claws 54 of the tire 53 are caught in claw grooves 55 of the wheel 43 to prevent the tire 53 from slipping off. The tire 53 covers the entire outer circumferential surface of the wheel 43 and almost the entire outer side surface of the wheel 43. Since the rubber tire 53 runs on the ground, scratches on the surface of the inspection object P can be suppressed. A center hole 53A is provided in the center of the tire 53 to avoid interference with the ball bearing 42 and the stopper ring 44.

[0050] A plastic tire cover 54 is placed over the outer surface of the tire 53 to prevent twisting of the tire 53. A nut 55 is press-fitted and fixed into the outer end of the bolt insertion hole 47 of the wheel 43. Bolt insertion holes 56, 57 are provided in the tire 53 and the tire cover 54, respectively. A bolt 58 is inserted into the bolt insertion holes 56, 57 from the outside and then tightened by the nut 55. This aligns and secures the tire 53 and tire cover 54 to the wheel 43. The bolt 58 is also a hexagon socket extra low head bolt similar to the above.

[0051] The attached tire 53 restricts the outward movement of the magnet 52F in the axial direction (the direction of the axis C3), suppressing displacement of the magnet 52F.

[0052] Four such mounting portions are provided at equal intervals in the circumferential direction for the tires 53. The mounting portion of the spur gear 46 and the mounting portion of the tires 53 are provided at the same position in the circumferential direction.

[0053] Next, a mounting structure for the rear wheel 13R will be described. The mounting structure for the rear wheel 13R is similar to the mounting structure for the front wheel 13F.

[0054] The rear wheel support member 61 is attached to the side wall portion 15B of the lower frame 15. The rear wheel support member 61 has a flange plate 62 and a support shaft 63 integrally formed therewith. A bolt insertion hole 64 is provided in the flange plate 62 at the front and rear of the support shaft 63. As shown in FIG. 7, the side wall portion 15B is provided with a shaft hole 65 and female threaded holes 66 positioned at the front and rear of the shaft hole 65. The support shaft 63 is inserted into the shaft hole 65 of the side wall portion 15B from the inside, and the flange plate 62 is overlapped on the inner surface of the side wall portion 15B. A bolt 67 is inserted into the bolt insertion hole 64 from the inside, and then tightened into the female threaded hole 66. This attaches the rear wheel support member 61 to the side wall portion 15B. The bolt 67 is a hexagon socket extra low head bolt similar to the above.

[0055] On the outside of the side wall portion 15B, a thrust washer 68 and a resin rear wheel 69 are rotatably attached in that order to the outer periphery of the support shaft 37. A stopper ring 70 for preventing the wheel 69 from coming off is fixed to the outer end face of the support shaft 63 by a screw (flat head screw) 71.

[0056] A spur gear 72 is formed integrally with the wheel 69. The wheel 69 is also provided with an internally threaded hole 73.

[0057] A rubber tire 74 is fitted and disposed on the wheel 69. A ring-shaped magnet fitting groove 75 is provided around the entire circumference on the inner surface of the outer periphery of the tire 74. A circular ring-shaped magnet, i.e., a rear wheel magnet 76R (76RL), is fitted and disposed in this magnet fitting groove 75. The magnet 76R is fitted into the magnet fitting groove 75 and fixed in place with an adhesive or the like.

[0058] A bolt insertion hole 77 is provided in the tire 74. A bolt 78 is inserted into the bolt insertion hole 77 from the outside and then tightened into the female thread hole 73. This fixes the tire 74 to the wheel 69. The bolt 78 is also a hexagon socket extra low head bolt similar to the above. Four such mounting portions for the tire 74 are provided at equal intervals in the circumferential direction.

[0059] An idle gear 81 for transmitting rotation between the front wheel spur gear 46 and the rear wheel spur gear 72 is rotatably attached to the side wall portion 15B of the lower frame 15. The idle gear 81 rotates about the left-right axis C5.

[0060] The gear support member 82 is attached to the side wall portion 15B of the lower frame 15. The gear support member 82 integrally has a flange plate 83 and a support shaft 84. As shown in Fig. 7, a shaft hole 85 is provided in the side wall portion 15B. The support shaft 84 is inserted into the shaft hole 85 of the side wall portion 15B from the inside, and the flange plate 83 is overlapped on the inner surface of the side wall portion 15B.

[0061] On the outside of the side wall portion 15B, a thrust washer 86 and an idle gear 81 are rotatably attached in that order to the outer periphery of a support shaft 84. A snap ring (E-ring or the like) 86 for preventing the idle gear 81 from coming off is attached to the outer periphery of the support shaft 63 adjacent to the outside of the idle gear 81. In this way, the idle gear 81 is rotatably attached to the side wall portion 15B, and is meshed with both the front wheel spur gear 46 and the rear wheel spur gear 72 so as to be able to transmit power.

[0062] As shown in Fig. 2, the front wheel 13F has a larger diameter than the rear wheel 13R, and the diameter DF of the front wheel 13F is larger than the diameter DR of the rear wheel 13R. The front wheel 13F and the rear wheel 13R are close to each other in the front-rear direction, and the wheelbase WB of both wheels is relatively short. Here, the wheelbase WB refers to the distance between the rotation centers C3 and C4 on an imaginary straight line T that passes through the rotation center C3 of the front wheel 13F and the rotation center C4 of the rear wheel 13R. In this embodiment, the rotation center C5 of the idle gear 81 is on the straight line T.

[0063] The front wheel (13F) has a wider contact width than the rear wheel (13R).

[0064] On the other hand, since the front wheel 13F and the rear wheel 13R are provided with magnets 52F and 76R, respectively, the front wheel 13F and the rear wheel 13R can be attracted to the surface of the inspection object P. In the case of this embodiment, the attraction force of the front wheel 13F to the surface of the inspection object P is stronger than that of the rear wheel 13R. To be advantageous in obtaining such characteristics, the magnet 52F of the front wheel 13F has a stronger magnetic force than the magnet 76R of the rear wheel 13R. For example, a neodymium magnet is used for the magnet 52F of the front wheel 13F, and a normal ferrite magnet is used for the magnet 76R of the rear wheel 13R. In addition, the magnet 52F of the front wheel 13F has a larger diameter than the magnet 76R of the rear wheel 13R.

[0065] 2, 7, and 8, the left front wheel 13FL and rear wheel 13RL are driven by a left drive motor 14L. The right front wheel 13FR and rear wheel 13RR are driven by a right drive motor 14R. These motors 14L, 14R are disposed sideways between the upper frame 16 and the lower frame 15 and attached to the upper frame 16. The motors 14L, 14R are composed of servo motors that can rotate continuously in forward and reverse directions.

[0066] FIG. 10 is a view of the upper frame 16 and the motors 14L, 14R attached thereto, viewed from below, with the lower frame 15 omitted. The front ear of the left driving motor 14L is fixed to the leg 17 at the foremost end of the upper frame 16 with two screws 82. The output shaft of the left driving motor 14L faces leftward, and a pinion gear 83 is attached to this output shaft. As shown in FIG. 2, the pinion gear 82 is engaged with a position diagonally above and in front of the front wheel spur gear 46. An L-shaped protrusion 84 for positioning the left driving motor 14L is integrally provided on the lower surface of the upper frame 16. The rear ear of the left driving motor 14L is cut away.

[0067] The left side drive motor 14L is disposed adjacent to or in contact with the upper frame 16, with its right side facing upward, its top surface facing left, and its front surface facing forward.

[0068] The right drive motor 14R is disposed adjacent to the rear of the left drive motor 14L, and is disposed symmetrically with the left drive motor 14L in the front-rear and left-right directions. The right drive motor 14R is configured with the same servo motor as the left drive motor 14L. The front ear of the right drive motor 14R is cut off.

[0069] The rear ear of the right drive motor 14R is fixed to the leg 17 at the rearmost end of the upper frame 16 with two screws 82. The output shaft of the right drive motor 14R faces rightward, and a pinion gear 85 is attached to this output shaft. This pinion gear 85 is engaged with a position diagonally above and rearward of the right front wheel spur gear 46, as shown by the imaginary line in FIG. 2. An L-shaped protrusion 86 for positioning the right drive motor 14R is integrally formed on the lower surface of the upper frame 16. This protrusion 86 is disposed symmetrically with the protrusion 84 in the front-rear and left-right directions.

[0070] The right drive motor 14R is disposed adjacent to or in contact with the upper frame 16, with its left side facing upward, its top surface facing right, and its front surface facing rear.

[0071] This configuration allows the two motors 14L, 14R to be installed in a small space, which contributes to making the traveling device 1 more compact and reducing the wheel base.

[0072] Two female screw holes 89 are provided on the bottom surface of each of the front and rear legs 17. The height of these legs 17 is equal to or slightly larger than the width of the motors 14L, 14R.

[0073] As shown in Fig. 8, the upper frame 16 to which the motors 14L, 14R are attached is placed on the lower frame 15, and the bolts 18 inserted through the lower frame 15 are tightened into the female screw holes 89 of the legs 17. This integrates the upper frame 16 and the lower frame 15. In this assembled state, the distance between the upper frame 16 and the lower frame 15 is equal to or slightly larger than the width of the motors 14L, 14R. This also contributes to making the traveling device 1 more compact.

[0074] Furthermore, when the vehicle body 11 is twisted or deformed during traveling, the motors 14L, 14R come into contact with at least one of the upper frame 16 and the lower frame 15, and are able to resist the twisting or deformation. Thus, the motors 14L, 14R are also used as part of the structure of the vehicle body 11, and the vehicle body rigidity can be increased. In this sense, it is preferable that the motors 14L, 14R be in contact with at least one of the upper frame 16 and the lower frame 15, and preferably both, from the beginning (immediately after assembly).

[0075] As shown in Figs. 2 and 3, the traveling device 1 includes a free wheel 90 positioned above the front wheel 13F. The free wheel 90 is attached to the upper and front ends of the left and right camera mounts 19 of the upper frame 16 via a support shaft 91 so as to be rotatable about the left and right axis C6. In the reference state of Fig. 2, the front end of the free wheel 90 is positioned forward of the front end of the front wheel 13F and forms the front end of the entire traveling device 1. However, as shown in Fig. 5, when the traveling device 1 is in the use state, the front end of the free wheel 90 no longer forms the front end of the entire traveling device 1 because the traveling device 1 is tilted backward from the reference state. As will be described in detail later, the free wheel 90 is mainly used when the traveling device 1 is moving backward (backing up).

[0076] 2, the traveling device 1 is configured so that when an inspection object P (shown by imaginary lines) perpendicular to the surface in a side view is pinched from below between the front wheels 13F and the rear wheels 13R, parts other than the front wheels 13F and the rear wheels 13R (particularly the idle gear 81 and the lower frame 15) do not come into contact with the inspection object P. The advantages of this will be described later. This configuration is largely due to the small wheelbase as described above.

[0077] 2 and 7, in the standard state, the straight line T is inclined upward toward the rear. Meanwhile, the rear lower surface portion 15C of the side wall portion 15B of the lower frame 15 is also inclined upward toward the rear. This raises the position of the lower surface portion of the side wall portion 15B, and as described above, when the inspection object P is caught between the front and rear wheels, it is possible to prevent the side wall portion 15B from coming into contact with the inspection object P. The inclination angle θ1 of the rear lower surface portion 15C with respect to the front-rear direction is slightly larger than the inclination angle θ2 of the straight line T.

[0078] A front end lower surface portion 15D of the side wall portion 15B of the lower frame 15 is also inclined upward toward the front.

[0079] On the other hand, as shown in Figures 5 and 6, when the traveling device 1 is in use, the front wheels 13F and rear wheels 13R are in contact with the surface of the inspection object P, so that the entire device is tilted downward toward the rear (i.e., tilted backward). Here, the inspection object P has a horizontal plane P1 and a vertical plane or vertical plane P2 that rises perpendicularly from the horizontal plane P1, and the front wheels 13F and rear wheels 13R are in contact with the horizontal plane P1. The traveling device 1 abuts against the vertical plane P2 located in front of it. In particular, the position of the foremost end of the traveling device 1 is the position of the foremost end of the front wheel 13F, and the position of the foremost end of the front wheel 13F abuts against the vertical plane P2 at an abutment point Q1.

[0080] On the other hand, when the traveling device 1 is tilted backward, the straight line T is also tilted backward and downward. The intersection Q2 of the straight line T and the vertical plane P2 is located above the contact point Q1 of the front wheel 13F. The specifications of each part are determined so that this is the case.

[0081] 3, a headlight 92 for illuminating the front is attached to the front end of the lower frame 15. The headlight 92 is configured with an LED.

[0082] Next, the operation of the traveling device 1 will be described.

[0083] During inspection, the traveling device 1 is attracted to the surface of the inspection object P by the magnets 52F, 76R. Then, the left and right front wheels 13F and rear wheels 13R are rotated and driven by the left and right motors 14L, 14R, and the traveling device travels forward in a four-wheel drive state. The traveling device 1 is mainly used for forward travel, and inspection is performed during this forward travel. By varying the rotation speeds of the left and right motors 14L, 14R, and thus the wheels 13, the traveling device 1 can turn. The traveling device 1 can make small turns in a very small arc.

[0084] If a suspicious location is found as a result of the visual inspection, the traveling device 1 is stopped, and the probe 27 is lowered by the lift mechanism 28 and brought into contact with the surface of the inspection target P. Then, an ultrasonic flaw detection test is performed. When this is completed, the probe 27 is raised again by the lift mechanism 28, the traveling device 1 starts traveling, and the visual inspection is continued.

[0085] There is a demand for a traveling device to be able to move onto a vertical surface that rises vertically from a horizontal surface without stopping. However, in general, the moment the traveling device traveling on the horizontal surface collides with the vertical surface, the traveling device stops without being able to climb up the vertical surface.

[0086] This will be explained using a comparative example shown in Fig. 12. In the traveling device 220 of this comparative example, the front wheels 221 and rear wheels 222 have the same diameter, have magnets of the same size, and have the same adsorptive force. When the front wheels 221 of the traveling device traveling forward on the horizontal plane P1 of the inspection object P collide with the vertical plane P2, the traveling device stops without climbing up the vertical plane P2.

[0087] However, the traveling device 1 of this embodiment can transfer onto the vertical surface P2. The state at this time will be described with reference to FIG.

[0088] As shown in (A), assume that the front wheel 13F of the traveling device 1 moving forward on the horizontal plane P1 of the object P to be inspected collides with the vertical plane P2. At this time, since the front wheel 13F has a larger diameter than the rear wheel 13R, the driving force escapes upward. In detail, the intersection Q2 of the straight line T passing through the rotation centers C3, C4 of the front wheel 13F and the rear wheel 13R with the vertical plane P2 is located higher than the contact point Q1 of the front wheel 13F. Therefore, when a forward driving force is applied to the traveling device 1, an upward force is generated that rolls the front wheel 13F up along the vertical plane P2, and the front wheel 13F can rise on the vertical plane P2.

[0089] After this, as shown in (B), the front wheel 13F rises while adhering to the vertical surface P2, and the rear wheel 13R moves forward while adhering to the horizontal surface P1, so that the traveling device 1 gradually rises at the front. After that, as shown in (C), the front wheel 13F rises further, the rear wheel 13R moves forward further, and as shown in (D), the rear wheel 13R also collides with the vertical surface P2 and is adhering to it.

[0090] As described above, according to this embodiment, it is possible to provide the traveling device 1 that can smoothly and continuously transfer from the horizontal plane P1 to the vertical plane P2 without stopping.

[0091] Next, another advantage of this embodiment will be described.

[0092] 14 shows a traveling device 220 of the comparative example when it tries to move from a vertical surface P2 to a horizontal surface P1. As shown in (A) and (B), in the traveling device 220 of this comparative example, the front wheel 221 comes off the inspection object P the moment it reaches the top of the vertical surface P2. Then, a rotational reaction force in the opposite direction to the rotational direction of the rear wheel 222 is applied to the vehicle body, causing the traveling device to rotate and fall off.

[0093] However, the traveling device 1 of this embodiment can transfer onto the horizontal plane P1. The state at this time will be described with reference to FIG.

[0094] As shown in (A), the traveling device 1 rises on the vertical surface P2 of the inspection object P. After this, as shown in (B), the front wheel 13F reaches the top of the vertical surface P2, but the moment it finishes the vertical surface P2, it immediately transfers onto the horizontal surface P1. This is because the adhesive force of the front wheel 13F is stronger than that of the rear wheel 13R. Even if a rotational reaction force acts in the opposite direction to the rotational direction of the rear wheel 13R, the adhesive force of the front wheel 13F exceeds it, and the front wheel 13F cannot be peeled off from the surface of the inspection object P, and the front wheel 13F smoothly and continuously transfers from the vertical surface P2 to the horizontal surface P1.

[0095] Thereafter, as shown in (C), the front wheel 13F moves further forward, and the rear wheel 13R rises further, and eventually the rear wheel 13R also moves onto the horizontal plane P1, as shown in (D).

[0096] As described above, according to this embodiment, even when transferring from the vertical plane P2 to the horizontal plane P1, the transfer can be made smoothly and continuously without stopping.

[0097] When transferring in this manner, as shown in (B) and (C), a right-angled corner P3 where a vertical plane P2 and a horizontal plane P1 intersect enters the gap between the front wheel 13F and the rear wheel 13R from below. However, at this time, only the front wheel 13F and the rear wheel 13R come into contact with the corner P3, so that obstacles to travel, increased travel resistance, snagging, damage to the traveling device 1, etc. due to contact can be prevented.

[0098] 16 shows, in the form of a stroboscopic photograph, how the traveling device 1 of this embodiment continuously moves from a vertical plane P2 to a horizontal plane P1 and back to a vertical plane P2. In particular, the length of the horizontal plane P1 in the traveling direction is sufficiently shorter than the wheelbase WB of the traveling device 1. This assumes that the traveling device 1 continuously moves from the front surface to the back surface of a plate-shaped inspection object P, such as a flange of an H-shaped steel or an L-shaped steel.

[0099] As described above, the transition is smooth when ascending the vertical surface P2 and then onto the horizontal surface P1. The transition is also smooth when traveling on the horizontal surface P1 and then descending the vertical surface P2. This is because the adhesive force of the front wheel 13F is stronger than that of the rear wheel 13R, and the transition can be led by the front wheel 13F. Even in this case, the corner P3 can be prevented from coming into contact with anything other than the front wheel 13F and the rear wheel 13R.

[0100] FIG. 17 shows, in the form of stroboscopic photographs, the traveling device 1 of this embodiment transferring onto various horizontal and vertical surfaces P1 and P2. The first scene I shows the transfer from the vertical surface P2 to the horizontal surface P1, but the horizontal surface P1 faces downward, and the traveling device 1 is turned upside down after the transfer. However, the traveling device 1 exerts sufficient adhesive force and can perform the transfer smoothly. The mechanism for transferring from the vertical surface P2 to the horizontal surface P1 is the same as the mechanism for transferring from the horizontal surface P1 to the vertical surface P2 described with reference to FIG. 13. The specifications of the traveling device 1 (especially the adhesive force and weight) are set so that it can withstand such transfers.

[0101] The second scene II shows the vehicle traveling upside down on a horizontal plane P1, then climbing up a vertical plane P2, and then climbing back up onto the horizontal plane P1. This is similar to the situation shown in Figure 16. This transition can also be performed smoothly.

[0102] The third scene III shows the robot moving down a vertical surface P2 after traveling on a horizontal surface P1. This is similar to the example shown in Figure 16, where the robot moves from the horizontal surface P1 to the vertical surface P2. The robot can also move smoothly.

[0103] In this way, the traveling device 1 of this embodiment can smoothly transition between the horizontal plane P1 and the vertical plane P2 that intersect at a right angle, and can perform inspection of inspection objects P of various shapes smoothly and continuously without stopping.

[0104] Incidentally, the traveling device 1 can also move backwards (back) as needed. At this time, as shown in Fig. 18, the adhesive force of the rear wheel 13R is weaker than that of the front wheel 13F, so the rear wheel 13R lifts up and does a wheelie.

[0105] In this embodiment, the free wheels 90 are grounded at this time, and the vehicle can travel using the free wheels 90 as driven wheels. This prevents the traveling device 1 from tipping over, and allows the vehicle to travel backwards without any problems.

[0106] A total of four wheels, the left and right front wheels 13F and the left and right free wheels 90, are in contact with the ground, allowing for stable running. Only the front wheels 13F are driven, and the running device 1 runs in two-wheel drive. However, reverse running is only temporary, so there is no problem. The running device 1 of this embodiment is basically intended to be used while running forward. The front end underside portion 15D of the lower frame 15 is inclined upward toward the front. This prevents the lower frame 15 from coming into contact with the road surface when a wheelie is performed.

[0107] Although the embodiment of the present disclosure has been described in detail above, various other embodiments and modifications of the present disclosure are possible.

[0108] (1) For example, the magnet of the rear wheel 13R can be omitted. In this case, the attractive force of the rear wheel 13R becomes zero, and the attractive force of the front wheel 13F is naturally greater than the attractive force of the rear wheel 13R.

[0109] (2) In the above embodiment, the horizontal plane P1 and the vertical plane P2 intersecting at a right angle are the targets, but any two surfaces (flat or curved surfaces) intersecting at an angle other than a right angle may be the targets. In other words, these two surfaces are not limited to the horizontal plane P1 and the vertical plane P2, and at least one of the two surfaces may be inclined with respect to the horizontal and / or vertical directions. The common angle between the two surfaces may also be an angle other than a right angle.

[0110] (3) The number of motors may be changed. For example, a motor may be provided for each of the left and right front wheels 13F and the rear wheel 13R, so that a total of four motors are provided.

[0111] The embodiments of the present disclosure are not limited to the above-described embodiments, and all modifications, applications, and equivalents encompassed within the spirit of the present disclosure as defined by the claims are included in the present disclosure. Therefore, the present disclosure should not be interpreted as being limited, and can be applied to any other technology that falls within the spirit of the present disclosure. [Explanation of symbols]

[0112] 1 Running gear 11 Body 12 Inspection Unit 13F Front wheel 13R rear wheel 14L, 14R motor 27 Probe 28 Lift mechanism 52F,76R Magnet 90 Free Wheel P Inspection object P1 horizontal plane P2 Vertical plane T straight line Q2 intersection Q1 Contact point

Claims

1. A traveling device that travels on a surface of an object to be inspected, the surface being subjected to non-destructive inspection of the object, the traveling device comprising: The car body and An inspection unit mounted on the vehicle body; Front and rear wheels rotatably mounted on the vehicle body; A motor that drives the front wheels and the rear wheels; A magnet provided on at least the front wheel; Equipped with The front wheels have a larger diameter than the rear wheels. A traveling device characterized by:

2. The adhesive force of the front wheels to the surface of the test object is stronger than the adhesive force of the rear wheels The traveling device according to claim 1.

3. The magnets are provided on the front wheels and the rear wheels, The magnets in the front wheels have a stronger magnetic force than the magnets in the rear wheels. The traveling device according to claim 1.

4. The front wheels and the rear wheels are provided with ring-shaped magnets, The magnets of the front wheels have a larger diameter than the magnets of the rear wheels. The traveling device according to claim 1.

5. A free wheel is provided above the front wheel. The traveling device according to claim 1.

6. The inspection unit includes: a probe for contacting a surface of the object to be inspected; a lift mechanism for raising and lowering the probe; Equipped The traveling device according to claim 1.

7. When the object to be inspected, which is perpendicular to the surface when viewed from the side, is sandwiched between the front and rear wheels from below, the object to be inspected is not contacted by any part other than the front and rear wheels. The traveling device according to claim 1.

8. the inspection target has a horizontal surface and a vertical surface rising perpendicularly from the horizontal surface, When the front and rear wheels of the traveling device are grounded on the horizontal surface and the front end of the front wheel of the traveling device abuts against the vertical surface, an intersection point where an imaginary line passing through a rotation center of the front wheel and a rotation center of the rear wheel intersects with the vertical surface is located above the abutment point of the front wheel and the vertical surface. The traveling device according to claim 1.

Images