Inspection device for assembly jig

Abstract

To provide an inspection device for an assembly jig capable of determining deterioration of assembly accuracy in an assembly jig.SOLUTION: An inspection device 50 comprises a first inspection member 51, a second inspection member 61, and an irradiation device 71. The first inspection member 51 comprises an inspection cylinder part 52 and a first confirmation part 56 having an inner diameter RT at a thread of a female screw of a cap part. The second inspection member 61 comprises a body part 62, a protrusion part 64, a second confirmation part 65 protruding from an outer peripheral surface of the protrusion part 64 and having a seal diameter RS of an O-ring, and an inspection hole 67.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an inspection device for an assembly jig. [Background technology]

[0002] As disclosed in Patent Document 1, a high-pressure tank is known as a container filled with a fuel gas such as hydrogen. The high-pressure tank has a base portion at an end of the body. The base portion has a female thread on its inner circumferential surface.

[0003] The valve assembly includes a high-pressure valve housed in a metal housing. The housing of the valve assembly includes a screw fastening portion including a male thread. The valve assembly also includes seal portions at the end and tip of the screw fastening portion.

[0004] The valve assembly is fastened to the cap by screwing the male thread of the screw fastening portion into the female thread of the cap. The seal portion comes into contact with the inner circumferential surface of the cap. This contact provides a sealing function that hermetically seals the fuel gas inside the high-pressure tank.

[0005] However, when the screw fastening portion of the valve assembly is fastened to the mouthpiece, if the screw fastening portion is inserted into the mouthpiece eccentrically or tilted, the seal portion provided on the screw fastening portion may come into contact with the female thread of the mouthpiece, causing the seal portion to be damaged. In order to prevent such damage to the seal portion, it is possible to use an assembly jig that suppresses the eccentricity and tilt of the screw fastening portion. As such an assembly jig, it is possible to use one that guides the valve assembly so that the central axis of the screw fastening portion coincides with the central axis of the female thread in order to suppress the eccentricity and tilt of the screw fastening portion. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2007-278472 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, if the assembly jig becomes deformed or worn due to repeated use, the guiding function of the assembly jig is reduced, and the assembly accuracy of the assembly jig is reduced. As a result, even if the assembly jig is used, the seal part of the valve assembly comes into contact with the female thread of the mouthpiece. For this reason, it is necessary to determine the deterioration of the assembly accuracy of the assembly jig. [Means for solving the problem]

[0008] The assembly jig inspection device for solving the above-mentioned problems is an assembly jig used when assembling a valve assembly to a mouthpiece by screwing a male thread formed on an outer peripheral surface of a fastening part of a valve assembly into a female thread formed on an inner peripheral surface of the mouthpiece, and is used to suppress interference between the female thread and a seal part that is located at a tip of the fastening part rather than the male thread in the axial direction of the fastening part, the assembly jig comprising: a first jig fixed to the outer periphery of the mouthpiece; and a second jig attached to the outer periphery of the first jig and comprising a plurality of guide rods that can be inserted into a plurality of insertion holes provided in the valve assembly, and the valve assembly is moved along the guide rods inserted into the insertion holes to detect a center axis of the fastening part and a center of the female thread. the valve assembly can be moved while its central axis is aligned with the central axis of the inspection device, and the inspection device comprises a first inspection member comprising: an inspection tube portion having the outer diameter of the mouth portion and to which the first jig is fixed, and a first confirmation portion protruding from the inner surface of the inspection tube portion toward the central axis of the inspection tube portion and having an inner diameter at the thread of the female screw; a second inspection member comprising: a main body portion having an insertion hole into which the guide rod can be inserted, a protrusion protruding from the main body portion and inserted into the inspection tube portion, a second confirmation portion protruding from the outer peripheral surface of the protrusion and having a seal diameter at the seal portion, and an inspection hole provided in the main body portion with its center on the central axis of the second confirmation portion and outside a virtual circle formed by projecting the outer peripheral surface of the second confirmation portion; and an illumination device that irradiates light to the inspection hole in the direction in which the protrusion protrudes from the main body portion.

[0009] In the inspection device, when the first jig is fixed to the outer periphery of the inspection tube portion, the first inspection member can reproduce the state in which the first jig is fixed to the outer periphery of the cap portion. Also, the first confirmation unit can reproduce the female thread of the cap portion on the inner periphery of the inspection tube portion. Then, when the second jig is attached to the outer periphery of the first jig, the guide rod of the second jig is inserted into the insertion hole of the second inspection member, and the state in which the valve assembly is attached to the guide rod can be reproduced. Then, when the second inspection member is moved along the guide rod and the protruding portion is inserted into the inspection tube portion, the second confirmation unit can reproduce the seal portion.

[0010] When the first inspection member and the second inspection member are viewed in the direction in which the central axis extends, a gap is formed between the inner peripheral surface of the first confirmation portion and the outer peripheral surface of the second confirmation portion. If the assembly accuracy of the assembly jig has not decreased at this time, tilt or eccentricity of the protrusion caused by the assembly jig has not occurred. Then, the central axis of the first confirmation portion and the central axis of the second confirmation portion coincide with each other, and the light of the inspection hole can be seen through the gap. Therefore, it can be determined that the assembly accuracy has not decreased due to the assembly jig.

[0011] On the other hand, if the assembly accuracy of the assembly jig is reduced, the protrusion will be tilted or eccentric. Then, the central axis of the first confirmation part and the central axis of the second confirmation part will not coincide with each other, and the light from the inspection hole may be difficult to see through the gap. Therefore, it can be determined that the assembly accuracy of the assembly jig has decreased. Therefore, by using the inspection device, it is possible to easily determine the decrease in the assembly accuracy of the assembly jig.

[0012] In the assembly jig inspection device, the inspection hole may be a plurality of circular holes. According to this, if the assembly precision of the assembly jig is reduced and the protrusion is tilted or decentered, the visibility of one of the multiple inspection holes is reduced, making it easy to check in which direction the protrusion is tilted or decentered.

[0013] In the assembly jig inspection device, the main body may have a plurality of long holes extending in an arc shape outside the protrusion. According to this, since the multiple inspection holes extend in an arc, if the protrusion is tilted or eccentric, the protrusion will hide part of the long hole, making it easy to check in which direction the protrusion is tilted or eccentric. Effect of the Invention

[0014] The present invention can determine the deterioration of the assembly accuracy of an assembly jig. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a partially cutaway cross-sectional view showing an assembly jig for a valve assembly. [Diagram 2] FIG. 2 is an exploded perspective view showing the assembly jig and the valve assembly. [Diagram 3] FIG. 3 is a perspective view showing the first inspection member. [Figure 4] FIG. 4 is a perspective view showing a second inspection member. [Diagram 5] FIG. 5 is a cross-sectional view showing the inspection device in use. [Figure 6] FIG. 6 is a diagram showing the results when the assembly accuracy is not decreased. [Figure 7] FIG. 7 is a diagram showing the results when the assembly accuracy is degraded. [Figure 8] FIG. 8 is a diagram showing another example of the inspection hole. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] An embodiment of an inspection device for an assembly jig will be described below with reference to Figures 1 to 7. First, the high-pressure tank will be described. <High pressure tank> As shown in Fig. 1, the high-pressure tank 10 includes a substantially cylindrical tank body 11 and a nozzle 12. The inside of the high-pressure tank 10 is filled with, for example, hydrogen gas as a fuel gas. Note that the inside of the high-pressure tank 10 may be filled with, for example, compressed gas or liquefied gas other than fuel gas. A filling space S1 is defined inside the tank body 11. The filling space S1 is filled with hydrogen gas.

[0017] The nozzle portion 12 is made of metal. The nozzle portion 12 is substantially cylindrical. The nozzle portion 12 is provided at the end of the tank main body portion 11 in the axial direction. The nozzle portion 12 defines a circular through hole 12h. The nozzle portion 12 includes a female thread 13 and a seal surface 14. The female thread 13 is formed on the inner peripheral surface of the nozzle portion 12, which is the surface that defines the through hole 12h in the nozzle portion 12. The central axis L1 of the female thread 13 coincides with the central axis of the nozzle portion 12. The inner diameter RT of the thread of the female thread 13 is a value that has a manufacturing tolerance in manufacturing. When the manufacturing tolerance of the female thread 13 is maximum on the plus side, the inner diameter RT is minimum, and when the manufacturing tolerance of the female thread 13 is maximum on the minus side, the inner diameter RT is maximum. The seal surface 14 is located closer to the inside of the tank main body portion 11 than the female thread 13 in the nozzle portion 12. The sealing surface 14 is a cylindrical surface.

[0018] The valve assembly 20 is screwed into the high-pressure tank 10 via the female thread 13 of the nozzle 12. This allows the valve assembly 20 to be detachably fastened to the nozzle 12. Hydrogen gas is then filled into the high-pressure tank 10 from a hydrogen supply source (not shown) via the valve assembly 20.

[0019] <Valve assembly> As shown in FIGS. 1 and 2, the valve assembly 20 includes a housing 21, a valve 22, a fastening portion 23, a male thread 24, an O-ring 27, and a nozzle .

[0020] The housing 21 is plate-shaped. Two circular insertion holes 25 are formed in the housing 21. Each of the two insertion holes 25 penetrates the housing 21 in the plate thickness direction. The centers of the two insertion holes 25 are located on an imaginary circle C. The imaginary circle C is a circle whose diameter is a straight line connecting the centers of the two insertion holes 25. The center of the imaginary circle C is located on the central axis L2 of the fastening portion 23. A guide rod 44 provided in the assembly jig 1 described later can be inserted into each of the two insertion holes 25.

[0021] The valve 22 is built into the housing 21. The valve 22 is an electromagnetic on-off valve. The valve 22 opens and closes the through hole 12h of the nozzle portion 12. The valve 22 is in an open state when hydrogen gas is being filled into the filling space S1 of the high-pressure tank 10. The valve 22 is in a closed state when filling of the hydrogen gas into the filling space S1 of the high-pressure tank 10 is completed.

[0022] The fastening portion 23 protrudes in a generally cylindrical shape from the center of the housing 21. The axial direction of the fastening portion 23 coincides with the plate thickness direction of the housing 21. A male thread 24 is formed on the outer circumferential surface of the fastening portion 23. The male thread 24 is screwed into the female thread 13 of the base portion 12.

[0023] The O-ring 27 as the seal portion is disposed closer to the tip of the fastening portion 23 than the male thread 24 in the axial direction of the fastening portion 23. The seal portion may be another seal ring such as a V-ring other than the O-ring 27. The O-ring 27 is seated on the seal surface 14 of the nozzle portion 12 when the valve assembly 20 is fastened to the nozzle portion 12. As a result, the O-ring 27 provides an axial seal between the seal surface 14 of the nozzle portion 12 and the outer circumferential surface of the fastening portion 23. In the valve assembly 20, the outer diameter of the O-ring 27 is defined as a seal diameter RS. This seal diameter RS ​​is smaller than the inner diameter RT of the female thread 13 and slightly larger than the inner diameter of the seal surface 14. The seal diameter RS ​​is a value having a manufacturing tolerance due to the O-ring 27 and the fastening portion 23. When the manufacturing tolerance is maximized on the plus side, the seal diameter RS ​​is maximized, and when the manufacturing tolerance is maximized on the minus side, the seal diameter RS ​​is minimized.

[0024] The nozzle 28 protrudes from the tip of the fastening portion 23. The nozzle 28 communicates between the inside of the high-pressure tank 10 and the valve 22 via the fastening portion 23. An assembly jig 1 is used when assembling the above-described valve assembly 20 to the mouthpiece 12 of the high-pressure tank 10. The assembly jig 1 will be described below.

[0025] <Assembly jig> The assembly jig 1 for the valve assembly 20 is used when assembling the valve assembly 20 to the mouth portion 12 by screwing the male thread 24 formed on the outer peripheral surface of the fastening portion 23 of the valve assembly 20 into the female thread 13 formed on the inner peripheral surface of the mouth portion 12. The assembly jig 1 is used to suppress interference between the O-ring 27 and the female thread 13.

[0026] As shown in FIGS. 1 and 2, the assembly jig 1 includes a first jig 30 and a second jig 40. The first jig 30 and the second jig 40 are arranged in a substantially rectangular shape. The first jig 30 is fixed to the outer periphery of the base portion 12. The first jig 30 includes a substantially cylindrical first body 31. The first body 31 includes a regulating ridge 33 at the tip of the first body 31. The regulating ridge 33 protrudes in an annular shape from the inner circumferential surface of the first body 31. The inner diameter of the regulating ridge 33 is smaller than the outer diameter of the base portion 12 and is the same as the inner diameter of the base portion 12. Note that the inner diameter of the regulating ridge 33 may be larger or smaller than the inner diameter of the base portion 12, as long as it is smaller than the outer diameter of the base portion 12.

[0027] The first body 31 is formed with a first through hole 31a, a mounting hole 31b, and a mounting groove 36. The central axis of the first jig 30 is a first central axis L10. The direction in which the first central axis L10 extends is the axial direction of the first jig 30. The first through hole 31a penetrates the first body 31 in the axial direction of the first jig 30 in the shape of a circular hole. The mouthpiece 12 is inserted into the first through hole 31a.

[0028] The mounting hole 31b is a female threaded hole for fixing the first jig 30 to the base portion 12. The mounting groove 36 is formed in the outer circumferential surface of the first body 31. An outer circumferential surface 360 ​​of the mounting groove 36 is also the outer circumferential surface of the first body 31.

[0029] The first body 31 is formed into a substantially cylindrical shape by integrally assembling two first body integral bodies 37. Each of the two first body integral bodies 37 is substantially semi-cylindrical. The two first body integral bodies 37 are halves obtained by dividing the first body 31 into two equal parts. Each of the two first body integral bodies 37 is connected by a fixing screw 39. The first body 31 can be separated into the two first body integral bodies 37 by removing the fixing screws 39 from the two first body integral bodies 37.

[0030] <Second jig> The second jig 40 is attached to the outer periphery of the first jig 30. The second jig 40 includes a plate-shaped second body 41. The plate thickness T of the second body 41 is slightly smaller than the opening width W of the mounting groove .

[0031] The second body 41 has a second through hole 41a and a plurality of fitting holes 43 formed therein. The second through hole 41a penetrates the second body 41 in the thickness direction of the second body 41 in the shape of a circular hole. The center axis of the second through hole 41a is a second center axis L20. The direction in which the second center axis L20 extends is the thickness direction of the second body 41. The diameter of the second through hole 41a is slightly larger than the outer diameter of the first body 31 at the mounting groove 36.

[0032] An inner peripheral surface 410 of the second body 41, which defines the second through hole 41a, is slidable relative to an outer peripheral surface 360 ​​of the mounting groove 36. No gap is formed between the inner peripheral surface 410 of the second body 41 and the outer peripheral surface 360 ​​of the mounting groove 36. Therefore, the first central axis L10 of the first jig 30 and the second central axis L20 of the second through hole 41a are coaxially positioned.

[0033] The two fitting holes 43 are arranged on a circle centered on the second central axis L20. A guide rod 44 is inserted into each of the fitting holes 43 and fitted therein. Thus, the second jig 40 is provided with two guide rods 44. The guide rods 44 are round metal rods. Both guide rods 44 extend parallel to each other. The axes of both guide rods 44 extend from the second body 41 parallel to the second central axis L20. Each guide rod 44 can be inserted into each of the multiple insertion holes 25 provided in the valve assembly 20.

[0034] The second body 41 is formed in a generally plate-like shape by integrally assembling two second body integral bodies 45. Each of the two second body integral bodies 45 is a half body obtained by dividing the second body 41 into two equal parts. One of the two second body integral bodies 45 has a connecting engagement piece 46, and the other of the two second body integral bodies 45 has a connecting engagement projection 47.

[0035] The second jig 40 is attached to the first jig 30 by assembling two second body forming bodies 45. Each of the two second body forming bodies 45 is disposed outside the first jig 30. The second body 41 and the second through hole 41a are formed by the engagement of the connecting engagement pieces 46 with the connecting engagement protrusions 47, and the second jig 40 is attached to the first jig 30. The second body 41 can be separated into two second body forming bodies 45 by releasing the engagement of the connecting engagement pieces 46 with the connecting engagement protrusions 47.

[0036] <How to install the valve assembly using an assembly jig> Next, a method of assembling the valve assembly 20 using the assembly jig 1 will be described. It is assumed that the first jig 30 is formed by assembling two first body forming bodies 37 together with fixing screws 39. It is also assumed that the engagement of the connecting engagement pieces 46 with the connecting engagement protrusions 47 is released, and the second jig 40 is disassembled into two second body forming bodies 45.

[0037] 1, the worker inserts the base portion 12 into the first through hole 31a until the tip of the base portion 12 abuts against the regulating ridge 33. At this time, no gap is formed between the outer circumferential surface of the base portion 12 and the inner circumferential surface of the first body 31 that defines the first through hole 31a. Therefore, the central axis L1 of the female thread 13 and the first central axis L10 of the first jig 30 are coaxially positioned.

[0038] After inserting the restricting member 35 into the mounting hole 31b, the worker screws the fixing screw 34 into the mounting hole 31b. The restricting member 35 is made of resin. Then, the first jig 30 is fixed to the outer periphery of the base portion 12.

[0039] Next, the worker attaches the second jig 40 to the first jig 30 to allow the inner circumferential surface 410 of the second body 41 to slide relative to the outer circumferential surface 360 ​​of the mounting groove 36. As a result, the first jig 30 is fixed to the outer periphery of the mouthpiece 12, and the inner circumferential surface 410 of the second body 41 is attached so as to be able to slide relative to the outer circumferential surface 360 ​​of the mounting groove 36. In this attached state, the outer circumferential surface 360 ​​of the mounting groove 36 and the inner circumferential surface 410 of the second body 41 are arranged concentrically with respect to the central axis L1 of the female thread 13.

[0040] Next, the worker fits the guide rods 44 into the fitting holes 43 of the second jig 40. After that, the worker inserts each guide rod 44 into the insertion holes 25 of the housing 21. Then, the central axis L1 of the female thread 13 in the cap portion 12 and the central axis L2 of the fastening portion 23 in the valve assembly 20 coincide with each other. In addition, the guide rods 44 extend parallel to the central axes L1, L2.

[0041] Next, the worker moves the valve assembly 20 along the guide rod 44 inserted into the insertion hole 25. As a result, the nozzle 28 and the fastening portion 23 pass inside the regulating ridge 33 and enter inside the mouthpiece 12. Furthermore, the nozzle 28 and the fastening portion 23 enter into the female thread 13 from their respective tips and pass through the inside of the female thread 13. The O-ring 27 also enters into the female thread 13 and passes through the inside of the female thread 13.

[0042] The valve assembly 20 moves toward the high-pressure tank 10 by the guide rod 44 while maintaining the central axis L2 of the fastening portion 23 and the central axis L1 of the female thread 13 aligned. Therefore, the assembly jig 1 moves the valve assembly 20 along the guide rod 44 inserted into the insertion hole 25, thereby making it possible to move the valve assembly 20 while maintaining the central axis L2 of the fastening portion 23 and the central axis L1 of the female thread 13 aligned. As a result, the fastening portion 23 passes through the inside of the female thread 13 without eccentricity due to the guide of the guide rod 44. Therefore, the O-ring 27 attached to the fastening portion 23 also passes through the inside of the female thread 13 without eccentricity. Therefore, the O-ring 27 is prevented from interfering with the female thread 13. Therefore, the assembly jig 1 is used to prevent interference between the O-ring 27, which is disposed at the tip of the fastening portion 23 closer to the male thread 24 in the axial direction of the fastening portion 23, and the female thread 13.

[0043] The worker inserts the fastening portion 23 of the valve assembly 20 into the nozzle portion 12 of the high-pressure tank 10 until the male threads 24 of the fastening portion 23 contact the female threads 13 of the nozzle portion 12 . Next, the worker rotates the valve assembly 20 around the central axis L2 of the fastening portion 23. The rotation of the valve assembly 20 is transmitted to the second jig 40 by the guide rod 44. Because the rotation of the first jig 30 is restricted, the inner circumferential surface 410 of the second body 41 slides on the outer circumferential surface 360 ​​of the mounting groove 36. As a result, the second jig 40 rotates integrally with the valve assembly 20. Then, as the valve assembly 20 rotates, the male thread 24 of the fastening portion 23 is screwed into the female thread 13.

[0044] Then, when the O-ring 27 comes out from the inside of the female thread 13, the O-ring 27 comes into contact with the seal surface 14. When the worker recognizes the resistance caused by the contact between the O-ring 27 and the seal surface 14, he or she stops rotating the valve assembly 20.

[0045] Thereafter, the worker removes the second jig 40 from the first jig 30, and removes the first jig 30 from the nozzle portion 12. The worker further rotates the valve assembly 20 about the central axis L2 of the fastening portion 23 as the rotation center, thereby fully tightening the valve assembly 20 to the nozzle portion 12. Then, the O-ring 27 of the fastening portion 23 seats on the seal surface 14 of the nozzle portion 12.

[0046] <Inspection device for valve assembly fixtures> As shown in FIG. 5, the inspection device 50 for the assembly jig 1 of the valve assembly 20 includes a first inspection member 51, a second inspection member 61, and an irradiation device 71.

[0047] <First inspection part> As shown in FIGS. 3 and 5, the first inspection member 51 includes an inspection tubular portion 52, a flange 54 protruding from the inspection tubular portion 52, and a first confirmation portion 56 integral with the inspection tubular portion 52.

[0048] The flange 54 protrudes from a first end 52a in the axial direction of the inspection tube portion 52. When the flange 54 is viewed in the plate thickness direction, the flange 54 has a rectangular shape. The first confirmation portion 56 protrudes in an annular shape from the inner peripheral surface 52b of the inspection tube portion 52 toward the central axis L3 of the inspection tube portion 52. The first confirmation portion 56 has a width along the extension direction of the central axis L3.

[0049] In the inspection tube portion 52, the inner diameter R1 at the inner circumferential surface 52b other than the first confirmation portion 56 is approximately the same as the inner diameter at the portion of the base portion 12 other than the female thread 13. The inner diameter R1 at the inner circumferential surface 52b of the inspection tube portion 52 may be different from the inner diameter at the portion of the base portion 12 other than the female thread 13. The outer diameter R2 at the outer circumferential surface 52c of the inspection tube portion 52 is the same as the outer diameter at the outer circumferential surface of the base portion 12. Therefore, the inspection tube portion 52 has the outer diameter of the base portion 12. The first jig 30 can be fixed to the outer circumferential surface 52c of the inspection tube portion 52 by the same method as the fixing method to the base portion 12.

[0050] In the inspection tube portion 52, the inner diameter R3 at the first confirmation portion 56 is the inner diameter of the thread of the above-mentioned female thread 13. In detail, the inner diameter R3 at the first confirmation portion 56 is set to the same value as the inner diameter RT when the manufacturing tolerance of the female thread 13 is maximum on the plus side, among the inner diameters RT.

[0051] <Second inspection part> As shown in FIGS. 4 and 5, the second inspection member 61 includes a main body portion 62, a protruding portion 64, a second confirmation portion 65, and an inspection hole 67.

[0052] The main body 62 is disk-shaped, but the shape of the main body 62 is arbitrary. Two circular insertion holes 63 are formed in the main body 62. Each of the two insertion holes 63 penetrates the main body 62 in the plate thickness direction. The center points of the two insertion holes 63 are located on an inspection-side imaginary circle C1 having the same diameter as the imaginary circle C of the valve assembly 20. The inspection-side imaginary circle C1 is a circle whose diameter is a straight line connecting the center points of the two insertion holes 63. Each of the two insertion holes 63 allows a guide rod 44 provided in the assembly jig 1 to be inserted.

[0053] The protrusion 64 protrudes in a generally cylindrical shape from the center of the main body 62. The direction in which the central axis L4 of the protrusion 64 extends coincides with the plate thickness direction of the main body 62. The second confirmation portion 65 protrudes in an annular shape from the outer circumferential surface of the protrusion 64, and has a width in the axial direction of the protrusion 64. The central axis of the second confirmation portion 65 coincides with the central axis L4 of the protrusion 64. For this reason, the central axis of the second confirmation portion 65 will be referred to as the "central axis L4."

[0054] The diameter T1 of the protrusion 64 is approximately the same as the diameter of the fastening portion 23. The diameter T1 of the protrusion 64 may be different from the diameter of the fastening portion 23, but is smaller than the diameter T2 of the second confirmation portion 65 described below. Therefore, the diameter T2 of the second confirmation portion 65 is larger than the diameter T1 of the protrusion 64. Also, the diameter T2 of the second confirmation portion 65 is smaller than the inner diameter RT of the first confirmation portion 56. The diameter T2 of the second confirmation portion 65 is set to the same value as the seal diameter RS ​​of the O-ring 27 described above when the manufacturing tolerance is maximum on the plus side. Therefore, the second inspection member 61 has the second confirmation portion 65 having the seal diameter RS ​​of the O-ring 27.

[0055] When the inspection device 50 is used, the protrusion 64 is inserted from the tip side of the inspection tube portion 52 of the first inspection member 51. When the inside of the inspection tube portion 52 is visually observed from the axial direction of the first inspection member 51 with the protrusion 64 inserted into the inspection tube portion 52 of the first inspection member 51, the second confirmation portion 65 is located inside the first confirmation portion 56.

[0056] A plurality of inspection holes 67 are formed in the main body 62. Each of the plurality of inspection holes 67 is a round hole. Each of the plurality of inspection holes 67 penetrates the main body 62 in the plate thickness direction. The plurality of inspection holes 67 are arranged at equal intervals so as to surround the base end of the protruding portion 64.

[0057] When the outer peripheral surface of the second confirmation portion 65 is projected onto the main body portion 62, an imaginary circle N is assumed to be formed along the outer peripheral surface of the second confirmation portion 65. This imaginary circle N is centered on the central axis L4 of the second confirmation portion 65, and is an imaginary circle that is formed when the outer peripheral surface of the second confirmation portion 65 is projected. Each of the multiple inspection holes 67 is disposed at equal intervals along the imaginary circle N. Furthermore, each of the multiple inspection holes 67 is aligned along the imaginary circle N.

[0058] <Irradiation device> The illumination device 71 illuminates light toward the inspection hole 67 of the second inspection member 61. The illumination device 71 illuminates the light into the inspection hole 67 along the direction in which the protruding portion 64 protrudes from the main body 62. The light illuminated from the illumination device 71 is illuminated into all of the multiple inspection holes 67.

[0059] <Inspection method using inspection equipment> The worker fixes the first jig 30 to the outer circumferential surface 52c of the inspection tube portion 52 in the same manner as the fixing method for the base portion 12. Then, the first inspection member 51 reproduces the state in which the first jig 30 is fixed to the outer circumferential surface of the base portion 12. Furthermore, the first confirmation portion 56 reproduces the female thread 13 of the base portion 12 on the inner periphery of the inspection tube portion 52. In detail, the first confirmation portion 56 reproduces a hole having the same inner diameter RT as the female thread 13.

[0060] Next, the worker attaches the second jig 40 to the first jig 30, so that the inner peripheral surface 410 of the second body 41 can slide relative to the outer peripheral surface 360 ​​of the mounting groove 36 of the first jig 30. As a result, the first jig 30 is fixed to the outer periphery of the inspection tube portion 52 of the first inspection member 51, and the inner peripheral surface 410 of the second body 41 is attached so as to be able to slide relative to the outer peripheral surface 360 ​​of the mounting groove 36 of the first jig 30. Then, a state in which the first jig 30 is fixed to the outer periphery of the mouthpiece portion 12 and the second jig 40 is attached to the first jig 30 can be reproduced.

[0061] Next, the worker fits the guide rods 44 into the fitting holes 43 of the second jig 40, and inserts the guide rods 44 into the fitting holes 43. After that, the worker inserts each guide rod 44 into the insertion hole 63 of the second inspection member 61. Then, the second inspection member 61 can reproduce the state in which the valve assembly 20 is attached to the guide rods 44.

[0062] Next, the worker moves the second inspection member 61 along the guide rod 44. As a result, the protrusion 64 and the second confirmation portion 65 pass through the inside of the regulating rib 33 and are inserted into the inspection tube portion 52. When the second inspection member 61 is moved until the main body portion 62 contacts the regulating rib 33, the second confirmation portion 65 is positioned inside the first confirmation portion 56. At this time, the O-ring 27 in the valve assembly 20 can be reproduced by the second confirmation portion 65. In detail, the seal diameter RS ​​is reproduced by the second confirmation portion 65.

[0063] Next, the worker turns on the irradiation device 71 and irradiates light from the main body 62 of the second inspection member 61 toward the protruding portion 64. Then, the worker visually checks the inspection device 50 from the flange 54 side of the first inspection member 51. The worker may also image the inspection device 50 and visually check the imaged data.

[0064] <Assembling accuracy check> Now, if the guide rod 44 extends straight, the second inspection member 61 moves toward the first inspection member 51 while maintaining the central axis L4 of the protruding portion 64 and the central axis L3 of the inspection tube portion 52 in alignment with each other due to the guide rod 44. Also, if there is no wear or the like on the outer circumferential surface 360 ​​in the mounting groove 36, the first central axis L10 of the first jig 30 and the second central axis L20 of the second jig 40 will be aligned. In this case as well, the second inspection member 61 moves toward the first inspection member 51 while maintaining the central axis L4 of the protruding portion 64 and the central axis L3 of the inspection tube portion 52 in alignment with each other due to the guide rod 44. In other words, if the assembly accuracy of the assembly jig 1 is not reduced, the protruding portion 64 will not be eccentric or tilted. Therefore, the second inspection member 61 moves toward the first inspection member 51 while maintaining the state in which the central axis L4 of the protruding portion 64 and the central axis L3 of the inspection tube portion 52 are aligned.

[0065] 5, a gap S is formed between the outer peripheral surface of the second confirmation portion 65 and the inner peripheral surface of the first confirmation portion 56. The radial dimension of the gap S is substantially constant over the entire circumferential direction of the gap S. The operator views the inside of the inspection tube portion 52 from the flange 54 side along the direction in which the central axes L3 and L4 extend.

[0066] When no eccentricity or inclination of the protrusion 64 occurs, all the inspection holes 67 are located between the outer peripheral surface of the second confirmation section 65 and the inner peripheral surface of the first confirmation section 56. In this case, as shown in FIG. 6, the worker can see the light irradiated by the irradiation device 71 through all the inspection holes 67. Since the inspection holes 67 are circular holes, the worker can see the circular light. Then, if any one of the multiple inspection holes 67 is not difficult to see, the worker determines that no deterioration in the assembly accuracy of the assembly jig 1 has occurred.

[0067] On the other hand, for example, if the guide rod 44 is bent, even if the second inspection member 61 moves along the guide rod 44, the central axis L4 of the protrusion 64 and the central axis L3 of the inspection tube portion 52 will not coincide with each other. In other words, the bent guide rod 44 will cause the protrusion 64 of the second inspection member 61 to tilt. Also, for example, if uneven wear or the like occurs on the outer circumferential surface 360 ​​of the mounting groove 36, the central axis L4 of the protrusion 64 and the central axis L3 of the inspection tube portion 52 will not coincide with each other. In this case, the protrusion 64 will become eccentric due to uneven wear or the like.

[0068] As described above, when the protrusion 64 is eccentric or inclined, as shown in FIG. 7, the radial dimension of the gap S is narrowed in a part of the circumferential direction of the gap S and is widened on the opposite side by 180 degrees. The radial dimension of the gap S is different throughout the circumferential direction of the gap S. In addition, most or all of the inspection hole 67 is hidden by the second confirmation unit 65 in the narrowed portion of the gap S. In this case, the worker has difficulty visually recognizing the light irradiated by the irradiation device 71. The worker can visually recognize the other inspection holes 67 as circular light. In this case, the worker determines that the assembly accuracy of the assembly jig 1 has decreased.

[0069] Depending on the degree of inclination or eccentricity of the protrusion 64, one inspection hole 67 may be entirely or partially hidden. The criteria for determining whether or not the assembly accuracy of the assembly jig 1 has decreased may be appropriately determined by the operator.

[0070] <Effects of the embodiment> In the above embodiment, the following advantageous effects can be obtained. (1) By assembling the assembly jig 1 to the inspection device 50, the state when the female thread 13 of the cap portion 12 and the male thread 24 of the valve assembly 20 are fastened can be reproduced. Furthermore, the first confirmation unit 56 and the second confirmation unit 65 of the inspection device 50 can reproduce the positional relationship between the female thread 13 of the cap portion 12 and the O-ring 27 of the valve assembly 20 when the assembly jig 1 is used. Then, the deterioration of the assembly accuracy of the assembly jig 1 can be determined by the way in which the light is visually recognized at the inspection hole 67 when the light is irradiated to the inspection hole 67 by the irradiation device 71. Therefore, by using the inspection device 50, the deterioration of the assembly accuracy of the assembly jig 1 can be easily determined.

[0071] (2) By using the inspection device 50, it is possible to determine whether or not the assembly accuracy of the assembly jig 1 has decreased, without actually using the assembly jig 1 to assemble the valve assembly 20 to the mouthpiece 12. This eliminates the need to inspect whether the O-ring 27 has been damaged due to interference with the female thread 13 after the valve assembly 20 has been fastened to the mouthpiece 12, and to perform follow-up work such as releasing the fastening between the mouthpiece 12 and the valve assembly 20 and replacing the valve assembly 20 if the O-ring 27 has been damaged.

[0072] (3) In the inspection device 50, the positional relationship between the female thread 13 and the O-ring 27 can be reproduced by the first confirmation section 56 and the second confirmation section 65. The positional relationship between the first confirmation section 56 and the second confirmation section 65 can be reproduced by the dimensional relationship at the gap S. Here, since the gap S is reproduced inside the inspection tube section 52, the visibility of the gap S itself is low. However, the gap S and the inspection hole 67 are associated with each other, and the illumination device 71 can illuminate the inspection hole 67 with light. This allows the inspection hole 67 to be visible by the light leaking from the inspection hole 67, thereby improving the visibility of the gap S. As a result, the positional relationship between the first confirmation section 56 and the second confirmation section 65 can be visually recognized, and therefore the assembly accuracy can be accurately determined.

[0073] (4) The inspection holes 67 are circular holes and are arranged in multiple locations around the protrusion 64. Therefore, if the assembly accuracy of the assembly jig 1 decreases and the protrusion 64 becomes tilted or eccentric, the visibility of any of the multiple inspection holes 67 decreases. This makes it easy to check in which direction the protrusion 64 is tilted or eccentric.

[0074] (5) The inner diameter RT of the first checking portion 56 is set to the same value as the inner diameter RT when the manufacturing tolerance of the female thread 13 is maximum on the plus side. In addition, the diameter T2 of the second checking portion 65 is set to the same value as the seal diameter RS ​​of the O-ring 27 when the manufacturing tolerance is maximum on the plus side. Therefore, the inspection device 50 can reproduce a state in which the manufacturing tolerance of the female thread 13 is maximum on the plus side and the manufacturing tolerance of the O-ring 27 is maximum on the plus side. In other words, the inspection device 50 can reproduce a state in which the female thread 13 and the O-ring 27 are most likely to interfere with each other. Therefore, if it is determined by the inspection by the inspection device 50 that there is no decrease in the assembly accuracy, the assembly jig 1 can be used to fasten the mouthpiece portion 12 and the valve assembly 20 without causing the O-ring 27 to interfere with the female thread 13.

[0075] <Example of change> The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0076] 8, the inspection holes 67 may be multiple long holes extending in an arc shape along an imaginary circle N outside the protrusion 64. In this case, since the multiple inspection holes 67 extend along the imaginary circle N, if the protrusion 64 is tilted or eccentric, part of the long holes will be hidden by the protrusion 64. This makes it easy to check in which direction the protrusion 64 is eccentric.

[0077] The number of the inspection hole 67 may be one. In this case, the inspection hole 67 extends in a substantially circular shape along the imaginary circle N outside the protruding portion 64. The number of inspection holes 67 may be changed as appropriate.

[0078] The inner diameter RT of the first confirmation portion 56 and the diameter T2 of the second confirmation portion 65 may be changed as appropriate within the range of manufacturing tolerances. For example, the inner diameter RT of the first confirmation portion 56 is set to the same value as the inner diameter RT of the female thread 13 when the manufacturing tolerance is maximum on the positive side. On the other hand, the diameter T2 of the second confirmation portion 65 may be set to the same value as the seal diameter RS ​​of the O-ring 27 when the manufacturing tolerance is minimum on the negative side.

[0079] Alternatively, the inner diameter RT of the first confirmation portion 56 may be set to the design median of the female thread 13, and the diameter T2 of the second confirmation portion 65 may be set to the design median of the seal diameter RS.

[0080] The first inspection member 51 does not have to include the flange 54. In the second inspection member 61, the shape and thickness of the protrusion 64 for providing the second confirmation portion 65 may be changed as appropriate as long as the seal diameter RS ​​can be reproduced by the second confirmation portion 65. For example, the protrusion 64 may be in the shape of a square prism or a cylinder.

[0081] In the first inspection member 51, as long as the inner diameter RT of the female thread 13 can be reproduced by the first confirmation portion 56, the first confirmation portion 56 may be a protrusion having almost no width in the axial direction or may have another shape. Furthermore, the first confirmation portion 56 may not be annular, but may have a shape formed with intervals in the circumferential direction.

[0082] In the second inspection member 61, as long as the seal diameter RS ​​can be reproduced by the second confirmation portion 65, the second confirmation portion 65 may be a protrusion that has almost no width in the axial direction or may have another shape. Furthermore, the second confirmation portion 65 does not have to be annular, and may have a shape formed with intervals in the circumferential direction. [Explanation of symbols]

[0083] C1...imaginary circle on the inspection side, 1...assembly jig for valve assembly, 12...base portion, 13...female thread, 20...valve assembly, 23...fastening portion, 24...male thread, 25...insertion hole, 27...O-ring as sealing portion, 30...first jig, 40...second jig, 44...guide rod, 50...inspection device, 51...first inspection member, 52...inspection tube portion, 56...first confirmation portion, 61...second inspection member, 62...main body portion, 63...insertion hole, 64...protrusion portion, 65...second confirmation portion, 67...inspection hole, 71...irradiation device.

Claims

1. An assembly jig used when assembling a valve assembly to a nozzle portion by screwing a male thread formed on an outer peripheral surface of a fastening portion of the valve assembly into a female thread formed on an inner peripheral surface of the nozzle portion, the assembly jig being used to suppress interference between the female thread and a seal portion located at a tip of the fastening portion closer to the male thread in the axial direction of the fastening portion, The assembly jig is A first jig fixed to an outer periphery of the nozzle portion; a second jig attached to an outer periphery of the first jig and including a plurality of guide rods that can be inserted into a plurality of insertion holes provided in the valve assembly, By moving the valve assembly along the guide rod inserted into the insertion hole, the valve assembly can be moved while a central axis of the fastening portion and a central axis of the female screw are aligned, The inspection device includes: a first inspection member including an inspection tube portion having an outer diameter of the base portion and to which the first jig is fixed, and a first confirmation portion protruding from an inner peripheral surface of the inspection tube portion toward a central axis line of the inspection tube portion and having an inner diameter at the thread of the female screw; a second inspection member including: a main body portion having an insertion hole formed therein through which the guide rod can be inserted; a protruding portion protruding from the main body portion and inserted into the inspection tube portion; a second confirmation portion protruding from an outer circumferential surface of the protruding portion and having a seal diameter at the seal portion; and an inspection hole provided in the main body portion, centered on a central axis of the second confirmation portion and located outside an imaginary circle onto which the outer circumferential surface of the second confirmation portion is projected; an illumination device that illuminates the inspection hole with light along the direction in which the protrusion protrudes from the main body portion, said illumination device comprising: an illumination unit that illuminates the inspection hole with light along the direction in which the protrusion protrudes from the main body portion;

2. 2. The assembly jig inspection device according to claim 1, wherein the inspection hole is a plurality of circular holes.

3. 2. The assembly jig inspection device according to claim 1, wherein said main body portion has a plurality of long holes extending in an arc shape outside said protrusion.

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