Looseness indicator
Patent Information
- Application Number
- PCT/JP2026/007238
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-28
- Filing Date
- 2026-02-26
- Publication Date
- 2026-10-01
Smart Images
Figure JP2026007238_01102026_PF_FP_ABST
Abstract
Description
Looseness indicator
[0001] The present disclosure relates to a looseness indicator.
[0002] An example of a wheel nut lock includes a central body, and a first extension and a second extension each extending from the central body. The central body has a toothed hole penetrating the central body along the central axis of the central body, and the toothed hole is defined by a plurality of raised portions extending along the central axis. In the wheel nut lock, the central body is attached to a wheel nut. The first extension comprises an indicator and a latch.
[0003] For a plurality of wheel nuts arranged along the circumferential direction of a wheel, one wheel nut lock is attached to one wheel nut. In this case, between a first wheel nut lock and a second wheel nut lock that are adjacent to each other in the circumferential direction, the latch of the first wheel nut lock engages with the second extension of the second wheel nut lock. Thereby, the indicator of the first wheel nut is covered by the second extension of the second wheel nut. When the rotation amount of the first wheel nut lock relative to the second wheel nut lock exceeds a predetermined magnitude, the latch of the first wheel nut lock disengages from the second extension of the second wheel nut lock, thereby exposing the indicator of the first wheel nut lock (see, for example, Patent Document 1).
[0004] International Publication No. 2013 / 049913
[0005] Incidentally, with wheel nut locks, when attaching one wheel nut lock to each of a plurality of wheel nuts, the indicator of each wheel nut cannot be visually recognized, and the indicator can only be visually recognized after the wheel nut has loosened. Therefore, according to wheel nut locks, while it is possible to detect loosening of a wheel nut from the exposure of the indicator, it is difficult to accurately detect the degree of loosening of the wheel nut.
[0006] A loosening indicator designed to solve the above problems is configured to be fastened one by one to each of a plurality of threaded members arranged along the circumferential direction of the wheel. The loosening indicator comprises a fastening portion configured to be fastened to the threaded members, an indicator portion extending from the fastening portion toward one of a pair of loosening indicators adjacent to the loosening indicator in the circumferential direction, and a display portion extending from the fastening portion toward the other loosening indicator of the pair of loosening indicators. The display portion is configured to face the indicator portion of the other loosening indicator in the circumferential direction and to indicate a reference position for determining the initial position of the indicator portion of the other loosening indicator.
[0007] According to the above-mentioned loosening indicator, the degree of loosening of the threaded member can be determined from the difference between the position of the indicator relative to the reference position before loosening occurs in the threaded member and the position of the indicator relative to the reference position after loosening occurs in the threaded member. Therefore, the degree of loosening of the threaded member can be detected with high accuracy.
[0008] In the above-described loosening indicator, the reference indicator portion may be located in a region that includes the central part of the outer shape of the indicator portion when viewed from a line of sight parallel to the axial direction of the screw member. With the above-described loosening indicator, the reference indicator portion is less likely to be damaged by friction or the like compared to the case where the reference indicator portion is located only on the outer edge of the indicator portion.
[0009] In the above-described loosening indicator, the indicator portion includes a frame-shaped portion extending from the fastening portion toward the other loosening indicator, and when viewed from the line of sight, the frame-shaped portion may surround the reference indicator portion.
[0010] According to the above loosening indicator, for example, an obstacle such as gravel, flying towards the reference indicator, will collide with the frame-shaped part, thereby preventing the obstacle from colliding with the reference indicator. As a result, damage to the reference indicator is minimized.
[0011] In the above-described loosening indicator, when viewed from the line of sight, the reference indicator portion may have a shape that tapers from the fastening portion toward the other loosening indicator, and the indicator portion may have a shape that tapers from the fastening portion toward the one loosening indicator.
[0012] According to the above loosening indicator, it is possible to determine the position of the tip of the indicator part based on the tip of the reference indicator part, making it easy to determine the initial position of the indicator part. In the above loosening indicator, the angle formed by the line segment connecting the center of the screw member and the tip of the indicator part, and the line segment connecting the center of the screw member and the tip of the reference indicator part, when viewed from the line of sight, may be 120° or more and 150° or less.
[0013] In the loosening indicator described above, the loosening indicator is configured to be fastened to the screw member and comprises an inner member included in the fastening portion and an outer member configured to be locked to the outer circumference of the inner member, and may be configured to allow rotation of the outer member relative to the inner member.
[0014] According to the above-mentioned loosening indicator, for example, after attaching the loosening indicator to the threaded member, the position of the outer member relative to the inner member can be adjusted by rotating the outer member relative to the inner member.
[0015] In the loosening indicator, the inner member has a plurality of locking teeth on its outer circumference that extend along the axial direction of the screw member, and the outer member has locking claws configured to engage with each locking tooth, and the outer member has a non-rotatable position in which the locking claws are engaged with the locking teeth and are unable to rotate relative to the inner member, and a rotatable position in which the locking teeth release the locking claws and the outer member is able to rotate relative to the inner member, and the distance between the wheel disc and the non-rotatable position in the axial direction of the screw member may be shorter than the distance between the wheel disc and the rotatable position.
[0016] According to the above loosening indicator, unnecessary rotation of the outer member relative to the inner member can be suppressed by positioning the outer member in a non-rotatable position, and the position of the outer member can be adjusted by positioning the outer member in a rotatable position.
[0017] In the above-described loosening indicator, the outer member may include the indicator unit and the display unit. With the above-described loosening indicator, the position of the indicator unit and the display unit can be adjusted by rotating the outer member relative to the inner member, without having to remove the loosening indicator from the screw member.
[0018] The looseness indicator of this disclosure can accurately detect the degree of looseness.
[0019] Figure 1 is an exploded perspective view showing the outer and inner members of the looseness indicator in disassembled form. Figure 2 is a plan view showing the structure of the outer member. Figure 3 is a plan view showing the structure of the inner member. Figure 4 is a perspective view showing the structure of a part of the inner member. Figure 5 is a perspective view showing the structure of the looseness indicator when the outer member is in a non-rotatable position. Figure 6 is a cross-sectional view showing the structure of the looseness indicator when the outer member is in a non-rotatable position. Figure 7 is a cross-sectional view showing the structure of the looseness indicator when the outer member is in a non-rotatable position. Figure 8 is a perspective view showing the structure of the looseness indicator when the outer member is in a rotatable position. Figure 9 is a cross-sectional view showing the structure of the looseness indicator when the outer member is in a rotatable position. Figure 10 is a cross-sectional view showing the structure of the looseness indicator when the outer member is in a rotatable position. Figure 11 is an operation diagram for explaining the operation of the looseness indicator. Figure 12 is an operation diagram for explaining the operation of the looseness indicator. Figure 13 is a plan view showing the structure of a modified example of the looseness indicator.
[0020] An embodiment of the looseness indicator will be described with reference to Figures 1 to 12. [Looseness Indicator] The looseness indicator will be described with reference to Figures 1 to 4.
[0021] The loosening indicator 10 shown in Figure 1 is fastened one to each of the multiple wheel nuts N (see Figure 5) arranged along the circumferential direction of the wheel disc. The wheel nuts N are an example of screw-type members. The loosening indicator 10 comprises an outer member 11 and an inner member 12. The inner member 12 is included in the fastening portion that fastens to the wheel nuts N.
[0022] In the example shown in Figure 1, the inner member 12 comprises a main body portion 12A, a plurality of locking teeth 12B, and a plurality of protrusions 12C. The inner member 12 is a resin molded product in which the main body portion 12A, the plurality of locking teeth 12B, and the plurality of protrusions 12C are integrally molded. The main body portion 12A has a cylindrical shape that extends along the axial DAN of the wheel nut N. The axial DAN of the wheel nut N is parallel to the axial direction of the inner member 12.
[0023] Each locking tooth 12B is located on the outer circumference of the main body 12A and extends along the axial DAN of the wheel nut N. The multiple locking teeth 12B are arranged at equal intervals in the circumferential direction of the main body 12A. The multiple protrusions 12C are arranged without gaps in the circumferential direction of the main body 12A.
[0024] The outer member 11 includes a main body portion 11A, an indicator portion 11B, and a display portion 11C. The outer member 11 is a resin molded product in which the main body portion 11A, the indicator portion 11B, and the display portion 11C are integrally molded. Of the outer member 11, the main body portion 11A is locked to the outer circumference of the inner member 12. The main body portion 11A has a cylindrical shape that extends along the axial DAN of the wheel nut N. The axial direction of the main body portion 11A is parallel to the axial DAN of the wheel nut N. The main body portion 11A has a two-stage cylindrical shape that expands in diameter along the direction toward the hub portion of the wheel disc in the axial DAN of the wheel nut N. The hub portion of the wheel disc is the part of the wheel disc to which the hub is fastened, and is a disc-shaped portion in which bolt holes are formed.
[0025] The main body portion 11A is composed of a first cylindrical portion 11A1 and a second cylindrical portion 11A2. The first cylindrical portion 11A1 and the second cylindrical portion 11A2 are aligned in the axial direction DAN of the wheel nut N, and the first cylindrical portion 11A1 is larger in diameter than the second cylindrical portion 11A2. The second cylindrical portion 11A2 has locking claws 11A21 that engage with each locking tooth 12B. The second cylindrical portion 11A2 has two locking claws 11A21, and the two locking claws 11A21 are equally spaced in the circumferential direction of the second cylindrical portion 11A2. Each locking claw 11A21 protrudes toward the space defined by the second cylindrical portion 11A2. The main body portion 11A is locked to the inner member 12 by the locking claws 11A21, thereby forming a fastening portion together with the inner member 12.
[0026] The indicator unit 11B extends from the fastening portion toward one of a pair of adjacent looseness indicators 10 in the circumferential direction of the wheel disc. In the example shown in Figure 1, the indicator unit 11B extends from the second cylindrical portion 11A2 of the main body portion 11A included in the fastening portion. The display unit 11C extends from the fastening portion toward the other of a pair of adjacent looseness indicators 10 in the circumferential direction of the wheel disc. In the example shown in Figure 1, the display unit 11C extends from the second cylindrical portion 11A2 of the main body portion 11A included in the fastening portion, similar to the indicator unit 11B.
[0027] The display unit 11C is located in the circumferential direction of the wheel disc, facing the indicator unit 11B of the other looseness indicator 10, and includes a reference display unit 11C2 that indicates a reference position for determining the initial position of the indicator unit 11B of the other looseness indicator 10. Each reference display unit 11C2 is a guide for determining the initial position of the indicator unit 11B of an adjacent looseness indicator 10 with respect to the looseness indicator 10 that has the reference display unit 11C2.
[0028] Figure 2 shows the planar structure of the outer member 11 as viewed from a line of sight parallel to the axial DAN of the wheel nut N. As shown in Figure 2, when viewed from a line of sight parallel to the axial DAN of the wheel nut N, the reference display section 11C2 is located in a region that includes the central part of the outer shape of the display section 11C. In the example shown in Figure 2, the outer shape of the display section 11C is approximately rectangular. The reference display section 11C2 is located in a region that includes the intersection of two diagonals that can be set relative to the outer shape of the display section 11C.
[0029] Compared to the case where the reference indicator 11C2 is located only on the outer edge of the display unit 11C, the reference indicator 11C2 is less likely to be damaged by friction or other factors. Also, because the reference indicator 11C2 is located in a region that includes the central part of the display unit 11C, the looseness indicator 10 is more likely to attract the attention of the viewer. For this reason, the reference indicator 11C2 can also be used as decoration for the wheel disc.
[0030] In the example shown in Figure 2, the display unit 11C includes a frame-shaped portion 11C1 extending from the fastening portion toward the other loosening indicator 10. The frame-shaped portion 11C1 extends away from the second cylindrical portion 11A2 of the outer member 11, starting from the second cylindrical portion 11A2. Together with the second cylindrical portion 11A2, the frame-shaped portion 11C1 defines a roughly rectangular space. When viewed from a line of sight parallel to the axial direction DAN of the wheel nut N, the frame-shaped portion 11C1 surrounds the reference display unit 11C2.
[0031] In the loosening indicator 10, for example, an obstacle such as gravel, if a portion of the obstacle flying towards the reference indicator unit 11C2, collides with the frame-shaped unit 11C1. This prevents the obstacle from colliding with the reference indicator unit 11C2, and as a result, damage to the reference indicator unit 11C2 is prevented.
[0032] When viewed from a line of sight parallel to the axial DAN of the wheel nut N, the reference indicator section 11C2 has a shape that tapers from the fastening section toward the other loosening indicator 10. Similarly, the instruction section 11B also has a shape that tapers from the fastening section toward the other loosening indicator 10. In the example shown in Figure 2, both the reference indicator section 11C2 and the instruction section 11B extend from the second cylindrical section 11A2 of the outer member 11 toward the second cylindrical section 11A2. The reference indicator section 11C2 defines a roughly triangular area together with the second cylindrical section 11A2. The instruction section 11B defines a roughly triangular space together with the second cylindrical section 11A2, similar to the reference indicator section 11C2.
[0033] Of the reference display section 11C2, the end furthest from the second cylindrical section 11A2 in the circumferential direction of the wheel disc is the tip 11C21. Of the indicator section 11B, the end furthest from the second cylindrical section 11A2 in the circumferential direction of the wheel disc is the tip 11B1. Since the position of the tip 11B1 of the indicator section 11B can be determined using the tip 11C21 of the reference display section 11C2 as a reference, the initial position of the indicator section 11B can be easily determined.
[0034] Furthermore, in the example shown in Figure 2, when viewed from a line of sight parallel to the axial direction DAN of the wheel nut N, and the axis of symmetry is the line segment passing through the center C and tip 11C21 of the wheel nut N, the reference display section 11C2 is substantially symmetrical, and the frame-shaped section 11C1 is also substantially symmetrical. Also, when the axis of symmetry is the line segment passing through the center C and tip 11B1 of the wheel nut N, the indicator section 11B is substantially symmetrical. Note that the center C of the wheel nut N coincides with the center of the second cylindrical section 11A2. Therefore, the loosening indicator 10 tends to enhance the aesthetic appearance of the wheel to which the loosening indicator 10 is attached. In addition, in the loosening indicator 10, when viewed from a line of sight parallel to the axial direction DAN of the wheel nut N, the indicator section 11B and the display section 11C do not have a plate shape, so the loosening indicator 10 can be made lighter.
[0035] When viewed from a line of sight parallel to the axial direction DAN of the wheel nut N, the angle θ formed by the line segment connecting the center C of the wheel nut N and the tip 11B1, and the line segment connecting the center C of the wheel nut N and the tip 11C21, is 120° or more and 150° or less. The angle θ is set according to the number of wheel nuts N used to fasten the hub to the hub portion of the wheel disc. For example, if there are 12 wheel nuts N, the angle θ may be 150°, and if there are 10 wheel nuts N, the angle θ may be 144°. If there are 8 wheel nuts N, the angle θ may be 135°, and if there are 6 wheel nuts N, the angle θ may be 120°.
[0036] The first cylindrical portion 11A1 has two grooves 11AG recessed toward the hub portion of the wheel disc at its boundary with the second cylindrical portion 11A2. The two grooves 11AG are equally spaced in the circumferential direction of the first cylindrical portion 11A1. The second cylindrical portion 11A2 has two slits 11A2S that penetrate the second cylindrical portion 11A2 along the axial DAN of the wheel nut N. The two slits 11A2S are equally spaced in the circumferential direction of the second cylindrical portion 11A2. Each slit 11A2S is aligned with one of the two grooves 11AG along the axial DAN of the wheel nut N. As a result, the portion of the second cylindrical portion 11A2 that is adjacent to the slits 11A2S in the circumferential direction of the second cylindrical portion 11A2 and adjacent to the grooves 11AG in the axial DAN of the wheel nut N functions as a cantilever beam 11AL. A locking claw 11A21 is positioned at the tip of each cantilever beam 11AL adjacent to the slit 11A2S. This allows the locking claw 11A21 to be displaced along the radial direction of the second cylindrical portion 11A2.
[0037] Figure 3 shows the planar structure of the inner member 12 as viewed from a line of sight parallel to the axial DAN of the wheel nut N. As shown in Figure 3, each protrusion 12C of the inner member 12 protrudes into the space defined by the main body 12A from the end of the wheel nut N in the axial DAN that is furthest from the hub of the wheel disc. When the inner member 12 is fastened to the wheel nut N, the corners of the wheel nut N fit into the grooves between the protrusions 12C. This suppresses relative movement of the inner member 12 with respect to the wheel nut N in the circumferential direction of the inner member 12.
[0038] Figure 4 is a perspective view showing the structure of a part of the inner member 12. As shown in Figure 4, the main body portion 12A of the inner member 12 has an outer peripheral surface 12AS. The main body portion 12A is provided with a locking ring 12A3 that protrudes from the outer peripheral surface 12AS along the radial direction of the main body portion 12A. The locking ring 12A3 has an annular shape that extends around the entire circumference of the main body portion 12A. In the plane determined by the diameter of the main body portion 12A and the axial direction DAN of the wheel nut N, the locking ring 12A3 has a rectangular cross-section, and the locking ring 12A3 has a series of rectangular cross-sections in the circumferential direction of the main body portion 12A.
[0039] Each locking tooth 12B has a shape that extends along the axial direction DAN of the wheel nut N. Each locking tooth 12B protrudes from the outer peripheral surface 12AS of the main body 12A along the radial direction of the wheel nut N. Multiple locking teeth 12B are arranged at equal intervals in the circumferential direction of the main body 12A. The distance between adjacent locking teeth 12B in the circumferential direction of the main body 12A is such that the locking claw 11A21 can be positioned between the locking teeth 12B. That is, the distance between adjacent locking teeth 12B in the circumferential direction of the main body 12A is greater than or equal to the width of the locking claw 11A21.
[0040] On the outer circumferential surface 12AS of the main body 12A, the portion sandwiched by the two locking teeth 12B in the circumferential direction of the main body 12A includes a first plane 12AS1, a second plane 12AS2, and an inclined surface 12AS3. In the axial direction DAN of the wheel nut N, the inclined surface 12AS3 is sandwiched between the first plane 12AS1 and the second plane 12AS2. The first plane 12AS1 is connected to the locking ring 12A3.
[0041] In the radial direction of the wheel nut N, the first plane 12AS1 is located outward from the second plane 12AS2. The inclined surface 12AS3 has an inclination such that, along the direction from the first plane 12AS1 toward the second plane 12AS2, the radial position of the wheel nut N moves inward as it approaches the second plane 12AS2.
[0042] The locking tooth 12B comprises a first element 12B1, a second element 12B2, and an inclined element 12B3. In the axial direction DAN of the wheel nut N, the inclined element 12B3 is sandwiched between the first element 12B1 and the second element 12B2. The first element 12B1 is connected to the locking ring 12A3. In the circumferential direction of the main body 12A, the first element 12B1 is sandwiched between the first plane 12AS1. In the circumferential direction of the main body 12A, the second element 12B2 is sandwiched between the second plane 12AS2. In the circumferential direction of the main body 12A, the inclined element 12B3 is sandwiched between the inclined surface 12AS3.
[0043] In the radial direction of the wheel nut N, the width of the second element 12B2 is greater than the width of the first element 12B1. In the radial direction of the wheel nut N, the width of the inclined element 12B3 gradually increases along the direction from the first element 12B1 to the second element 12B2.
[0044] [Rotating Mechanism] With reference to FIGS. 5 to 10, a mechanism related to rotation of an outer member 11 relative to an inner member 12 in a looseness indicator 10 will be described. FIGS. 5 to 7 show a state where the outer member 11 is locked to the inner member 12, in a state where rotation of the outer member 11 relative to the inner member 12 is disabled. In contrast, FIGS. 8 to 10 show a state where the outer member 11 is locked to the inner member 12, in a state where rotation of the outer member 11 relative to the inner member 12 is enabled.
[0045] As shown in FIG. 5, when attaching the looseness indicator 10 to a wheel nut N, for example, the looseness indicator 10 is attached to the wheel nut N in a state where rotation of the outer member 11 relative to the inner member 12 is disabled. When attaching the outer member 11 to the inner member 12, for example, the outer member 11 and the inner member 12 are arranged such that a first cylindrical portion 11A1 of the outer member 11 and a convex portion 12C of the inner member 12 face each other. Next, the inner member 12 is pushed into a main body portion 11A of the outer member 11, or the main body portion 11A of the outer member 11 is pushed onto the inner member 12. As a result, the inner member 12 is locked to a second cylindrical portion 11A2 of the main body portion 11A.
[0046] In the example shown in FIGS. 5 and 8, the length of the wheel nut N is longer than the length of the looseness indicator 10 in the axial direction DAN of the wheel nut N. This allows the wheel nut N with the looseness indicator 10 attached thereto to be loosened or tightened. Note that the length of the wheel nut N may be equal to or less than the length of the looseness indicator 10.
[0047] FIG. 6 is a cross-section along a plane defined by the axial direction DAN of the wheel nut N and the diameter of a main body portion 12A, showing the structure of the looseness indicator 10 in a cross-section including a locking claw 11A21 of the outer member 11.
[0048] As shown in FIG. 6, the locking claw 11A21 of the outer member 11 is in contact with the second flat surface 12AS2 on the outer circumferential surface 12AS of the main body 12A and positioned between the pair of locking teeth 12B. Accordingly, the locking claw 11A21 is sandwiched between the respective second elements 12B2 of the pair of locking teeth 12B in the circumferential direction of the main body 12A.
[0049] FIG. 7 is a cross-sectional view taken along a plane orthogonal to the axial direction DAN of the wheel nut N and including the diameter of the main body 12A, and shows the structure of the looseness indicator 10 in a cross-section including the locking claw 11A21 of the outer member 11.
[0050] As shown in FIG. 7, the locking claw 11A21 of the outer member 11 is positioned between a pair of mutually adjacent locking teeth 12B in the circumferential direction of the main body 12A. As previously described with reference to FIG. 6, the locking claw 11A21 is in contact with the second flat surface 12AS2 of the outer circumferential surface 12AS, so the second elements 12B2 of the locking teeth 12B are positioned on both sides of the locking claw 11A21. Therefore, even if an attempt is made to rotate the outer member 11 along the circumferential direction of the inner member 12, the width of the locking teeth 12B in the radial direction of the main body 12A is large, so the locking claw 11A21 cannot climb over the locking teeth 12B positioned on both sides of the locking claw 11A21. Therefore, the outer member 11 cannot rotate relative to the inner member 12.
[0051] As described above, the outer member 11 has a non-rotatable position where the locking claw 11A21 is locked by the locking teeth 12B, and thereby the outer member 11 cannot rotate relative to the inner member 12. The non-rotatable position is the position of the outer member 11 where the locking claw 11A21 of the outer member 11 is in contact with the second flat surface 12AS2 on the outer circumferential surface 12AS of the main body 12A.
[0052] As shown in FIG. 8, since the locking claw 11A21 of the outer member 11 is positioned at the tip end of the cantilever 11AL, the outer member 11 can be pulled up in a direction away from the hub portion of the wheel disc along the axial direction DAN of the wheel nut N. At this time, the locking claw 11A21 of the outer member 11 moves while being in contact with the second flat surface 12AS2 positioned between the pair of locking teeth 12B and the inclined surface 12AS3.
[0053] Figure 9, similar to Figure 6, shows the structure of the loosening indicator 10 in a cross-section along a plane determined by the axial DAN of the wheel nut N and the diameter of the main body portion 12A, including the locking claw 11A21 of the outer member 11.
[0054] As shown in Figure 9, the locking claw 11A21 is restricted from moving in the axial direction DAN by contacting the locking ring 12A3. As a result, the locking claw 11A21 contacts the first plane 12AS1. Therefore, the locking claw 11A21 is sandwiched between the first element 12B1 of the locking teeth 12B in the circumferential direction of the main body 12A. In this way, the locking claw 11A21 is pulled up while maintaining contact with the outer circumferential surface 12AS of the main body 12A, so even if the outer member 11 moves relative to the inner member 12, the outer member 11 remains locked to the inner member 12.
[0055] As shown in Figure 10, the locking claw 11A21 of the outer member 11 is located between a pair of adjacent locking teeth 12B in the circumferential direction of the main body 12A. As explained earlier with reference to Figure 9, since the locking claw 11A21 is in contact with the first plane 12AS1 of the outer circumferential surface 12AS, the first element 12B1 of the locking teeth 12B is located on both sides of the locking claw 11A21. Therefore, when attempting to rotate the outer member 11 along the circumferential direction of the inner member 12, the width of the locking teeth 12B in the radial direction of the main body 12A is small, allowing the locking claw 11A21 to overcome the locking teeth 12B located on both sides of the locking claw 11A21. As a result, the outer member 11 can rotate relative to the inner member 12.
[0056] Thus, the outer member 11 has a rotatable position in which the locking claw 11A21 is released from locking by the locking teeth 12B, thereby allowing it to rotate relative to the inner member 12. The rotatable position is the position of the outer member 11 in which the locking claw 11A21 of the outer member 11 contacts the first plane 12AS1 on the outer peripheral surface 12AS of the main body 12A. In the axial DAN of the wheel nut N, the distance between the wheel disc and the non-rotatable position is shorter than the distance between the wheel disc and the rotatable position.
[0057] The loosening indicator 10 prevents unnecessary rotation of the outer member 11 relative to the inner member 12 by positioning the outer member 11 in a non-rotatable position. For example, when the loosening indicator 10 is attached to the wheel nut N, positioning the outer member 11 in a non-rotatable position prevents the position of the outer member 11 from changing due to factors other than the loosening of the wheel nut N. Furthermore, the loosening indicator 10 allows the position of the outer member 11 to be adjusted by positioning it in a rotatable position. In addition, by rotating the outer member 11 relative to the inner member 12, the positions of the indicator unit 11B and the display unit 11C can be adjusted without removing the loosening indicator 10 from the wheel nut N.
[0058] [Operation] The operation of the looseness indicator 10 will be explained with reference to Figures 11 and 12. Figure 11 shows the initial position of the looseness indicator 10 when no looseness has occurred in each wheel nut N to which the looseness indicator 10 is attached.
[0059] As shown in Figure 11, adjacent looseness indicators 10 in the circumferential direction of the wheel disc are spaced apart from each other in the circumferential direction of the wheel disc. The looseness indicator 10 is attached to the wheel nut N such that, for example, the tip 11B1 of the indicator portion 11B faces the tip 11C21 of the reference indicator portion 11C2 of the adjacent looseness indicator 10 in the circumferential direction of the wheel disc, and the distance between the tips 11B1 and 11C21 is minimized. The tip 11B1 of the indicator portion 11B is positioned on a straight line connecting the center C of the wheel nut N in the adjacent looseness indicator 10 and the tip 11C21 of the reference indicator portion 11C2.
[0060] As shown in Figure 12, for example, if the wheel nut N located on the right side of the paper rotates counterclockwise, the distance between the tips 11B1 and 11C21 of the loosening indicator 10 expands compared to when the loosening indicator 10 is in its initial position. In this way, the loosening indicator 10 allows the degree of loosening of the wheel nut N to be determined from the difference between the position of the indicator 11B relative to the reference position before the wheel nut N loosens and the position of the indicator 11B relative to the reference position after the wheel nut N loosens. Therefore, the degree of loosening of the wheel nut N can be detected with high accuracy.
[0061] As described above, according to one embodiment of the looseness indicator, the following effects can be obtained: (1) The degree of looseness of the wheel nut N can be determined from the difference between the position of the indicator unit 11B relative to the reference position before the wheel nut N loosens and the position of the indicator unit 11B relative to the reference position after the wheel nut N loosens. Therefore, the degree of looseness of the wheel nut N can be detected with high accuracy.
[0062] (2) Compared to the case where the reference display section 11C2 is located only on the outer edge of the display section 11C, the reference display section 11C2 is less likely to be damaged by friction or the like. (3) Collisions of obstacles with the reference display section 11C2 are suppressed, and as a result, damage to the reference display section 11C2 is suppressed.
[0063] (4) Since the position of the tip 11B1 of the indicator 11B can be determined using the tip 11C21 of the reference indicator 11C2 as a reference, the initial position of the indicator 11B can be easily determined. (5) After attaching the loosening indicator 10 to the wheel nut N, the position of the outer member 11 relative to the inner member 12 can be adjusted by rotating the outer member 11 relative to the inner member 12.
[0064] (6) By positioning the outer member 11 in a non-rotatable position, unnecessary rotation can be suppressed, and by positioning the outer member 11 in a rotatable position, the position of the outer member 11 can be adjusted.
[0065] (7) By rotating the outer member 11 relative to the inner member 12, the positions of the indicator unit 11B and the display unit 11C can be adjusted without removing the loosening indicator 10 from the wheel nut N.
[0066] The above-described embodiment can be implemented with the following modifications: [Looseness indicator] The looseness indicator 10 may be composed of a single resin molded product. In this case, the looseness indicator 10 may be a resin molded product in which the fastening part, the indicator part 11B, and the display part 11C are integrally molded.
[0067] - The outer member 11 may not have an indicator section 11B and a display section 11C, while the inner member 12 may have an indicator section and a display section. In this case, the outer member 11 may have a slit that allows the indicator section and display section of the inner member 12 to protrude outside the outer member 11 in the radial direction of the wheel. Alternatively, the outer member 11 may have an indicator section 11B while the inner member 12 has a display section, or the outer member 11 may have a display section 11C while the inner member 12 has an indicator section.
[0068] The angle θ formed by the line segment connecting the center C of the wheel nut N and the tip 11B1 of the indicator part 11B, and the line segment connecting the center C of the wheel nut N and the tip 11C21 of the reference indicator part 11C2, may be less than 120° or greater than 150°. The angle θ may be changed according to the number of wheel nuts N used to fix one wheel disc.
[0069] - The reference indicator section 11C2 may have a shape with a single width in the direction from the fastening section toward the loosening indicator 10, or it may have a shape that widens towards the end in the direction from the fastening section toward the loosening indicator 10.
[0070] The indicator section 11B may have a shape with a single width in the direction from the fastening section toward the adjacent loosening indicator 10, or it may have a shape that widens towards the end in the direction from the fastening section toward the adjacent loosening indicator 10.
[0071] - When viewed from a line of sight parallel to the axial DAN of the wheel nut N, the display unit 11C may have a plate-like shape that extends from the fastening portion toward the adjacent loosening indicator 10 and has a predetermined outer shape. In this case, the reference display unit 11C2 only needs to be located within the display unit 11C when viewed from a line of sight parallel to the axial DAN of the wheel nut N, and may be, for example, letters or symbols attached to the display unit 11C.
[0072] - When viewed from a line of sight parallel to the axial direction DAN of the wheel nut N, the indicator portion 11B may extend from the fastening portion toward the adjacent loosening indicator 10 and have a plate-like shape with a predetermined outer shape.
[0073] - The reference display section 11C2 may be located only on the outer edge of the display section 11C. - The reference display section may consist of at least one of letters, numbers, symbols, and a predetermined structure.
[0074] For example, as shown in Figure 13, each looseness indicator 20 includes a fastening portion 21A, an indicator portion 21B extending from the fastening portion 21A, and a display portion 21C extending from the fastening portion 21A toward the opposite side of the indicator portion 21B. The indicator portion 21B of one looseness indicator 20 is located on the hub portion side of the wheel disc relative to the display portion 21C of the other looseness indicator 20, and superimposes on the display portion 21C of the other looseness indicator 20.
[0075] In this case, the reference display section 21C2 may be a through hole, which is an example of a predetermined structure. The reference display section 21C2 penetrates the display section 21C along the axial direction of the wheel nut N. The display section 21C may also further have the letter "S" as a reference display section 21C3 to determine the initial position. If the display section 21C of one loosening indicator 20 is located on the hub side of the wheel disc relative to the indicator section 21B of the other loosening indicator 20, and superimposes on the indicator section 21B of the other loosening indicator 20, the display section 21C may have both a reference display section 21C2 that penetrates the display section 21C and a reference display section 21C3 which is a letter, or it may have only one of the reference display sections 21C2 and 21C3.
[0076] [Threaded Member] The threaded member to which the fastening portion of the loosening indicator 10 is fastened is not limited to a wheel nut N. The threaded member may be, for example, a wheel bolt.
[0077] 10...Loosening indicator 11...Outer member 11A21...Locking claw 11B...Indicator part 11B1, 11C21...Tip 11C...Display part 11C1...Frame-shaped part 11C2...Reference display part 12...Inner member 12B...Locking tooth N...Wheel nut
Claims
1. A loosening indicator configured to be fastened one to each of a plurality of threaded members arranged along the circumferential direction of a wheel disc, comprising: a fastening portion configured to be fastened to the threaded member; an indicator portion extending from the fastening portion toward one of a pair of loosening indicators adjacent to the loosening indicator in the circumferential direction; and a display portion extending from the fastening portion toward the other of the pair of loosening indicators, wherein the display portion faces the indicator portion of the other loosening indicator in the circumferential direction and includes a reference display portion indicating a reference position for determining the initial position of the indicator portion of the other loosening indicator.
2. The loosening indicator according to claim 1, wherein, when viewed from a line of sight parallel to the axial direction of the screw member, the reference display portion is located in a region including the central portion of the outer shape of the display portion.
3. The loosening indicator according to claim 2, wherein the display unit comprises a frame-shaped portion extending from the fastening portion toward the other loosening indicator, and as viewed from the line of sight, the frame-shaped portion surrounds the reference display unit.
4. The loosening indicator according to claim 3, wherein, when viewed from the line of sight, the reference indicator portion has a shape that tapers from the fastening portion toward the other loosening indicator, and the indicator portion has a shape that tapers from the fastening portion toward the one loosening indicator.
5. The loosening indicator according to claim 4, wherein, when viewed from the line of sight, the angle formed by the line segment connecting the center of the screw member and the tip of the indicator part and the line segment connecting the center of the screw member and the tip of the reference display part is 120° or more and 150° or less.
6. The loosening indicator according to claim 1, which is configured to be fastened to the screw member and comprises an inner member included in the fastening portion and an outer member configured to be locked to the outer circumference of the inner member, wherein the outer member is configured to be rotatable relative to the inner member.
7. The loosening indicator according to claim 6, wherein the inner member has a plurality of locking teeth on its outer circumference extending along the axial direction of the screw member, the outer member has a locking claw configured to engage with each locking tooth, the outer member has a non-rotatable position in which the locking claw is engaged with the locking teeth and is unable to rotate relative to the inner member, and a rotatable position in which the locking teeth release the locking claw and it is able to rotate relative to the inner member, and the distance between the wheel disc and the non-rotatable position in the axial direction of the screw member is shorter than the distance between the wheel disc and the rotatable position.
8. The loosening indicator according to claim 6 or 7, wherein the outer member includes the indicator unit and the display unit.