Toilet seat fastening assembly

The fastening assembly with a dual-threaded fastener, coil nut, and follower mechanism addresses inefficiencies in toilet seat installation, enabling rapid, secure, and concealed mounting to toilet bowls while preventing over-tightening.

WO2026039763A1PCT designated stage Publication Date: 2026-02-19BEMIS MANUFACTURING CO
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Patent Information

Application Number
PCT/US2025/042226
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-08-16
Filing Date
2025-08-15
Publication Date
2026-02-19

AI Technical Summary

Technical Problem

Existing fastening systems for toilet seats are inefficient and require complex installation, especially in restricted spaces like toilet bowls with blind bores, and lack mechanisms to prevent over-tightening.

Method used

A fastening assembly featuring a threaded fastener with dual threaded regions, a coil nut, and a follower mechanism that allows for rapid top-installation and top-tightening, utilizing a shear segment to prevent over-tightening, and a helical washer for secure mounting to toilet bowls.

Benefits of technology

Enables efficient, rapid, and secure mounting of toilet seats to toilet bowls, even in restricted areas, with a mechanism to prevent over-tightening and ensure a clean, concealed installation.

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Abstract

A fastening assembly may include a nut, a follower coupled to the nut, and a fastener. The fastener includes a head and a shaft configured to extend into a bore of the toilet bowl. The shaft has a first threaded region and a second threaded region that is different from the first threaded region. The follower engages the first threaded region and translates the nut toward the second threaded region in response to rotation of the fastener. When the nut reaches the second threaded region, the nut engages the second threaded region and translates toward the head in response to rotation of the fastener.
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Description

Attorney Docket No. 015005-0036-W001TOILET SEAT FASTENING ASSEMBLYCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to U.S. Provisional Patent Application No. 63 / 684,053, filed August 16, 2024, the entire contents of which are incorporated herein by reference.FIELD OF THE DISCLOSURE

[0002] The present disclosure relates to fastening assemblies for coupling two objects or items together, and more particularly, to fastening assemblies that couple a toilet seat hinge of a toilet seat / lid to a toilet bowl.SUMMARY

[0003] The present disclosure provides, in one aspect, a fastening assembly for mounting a toilet seat to a toilet bowl, the fastening assembly including: a nut; a follower coupled to the nut; a fastener having a head and a shaft configured to extend into a bore of the toilet bowl, the shaft having a first threaded region and a second threaded region that is different from the first threaded region; wherein the follower engages the first threaded region and translates the nut toward the second threaded region in response to rotation of the fastener, and wherein when the nut reaches the second threaded region, the nut engages the second threaded region and translates toward the head in response to rotation of the fastener.

[0004] The present disclosure provides, in another aspect, a fastening assembly for mounting a toilet seat to a toilet bowl, the fastening assembly including: a fastener having a head and a shaft configured to extend into a bore of the toilet bowl; and a coil nut surrounding the shaft and including a flange, a nut, and a helical washer disposed between the flange and the nut, wherein, in response to rotation of the fastener, the nut engages the shaft and translates toward the head, compressing the helical washer between the toilet bowl and the nut.

[0005] The present disclosure provides, in another aspect, a fastening assembly for mounting a toilet seat to a toilet bowl, the fastening assembly including: a fastener having a head and a shaft configured to extend into a bore of the toilet bowl; a coil nut surrounding the shaft andAttorney Docket No. 015005-0036-W001 including a flange, a nut, and a helical washer disposed between the flange and the nut; and a follower coupled to the nut, wherein, in response to initial rotation of the fastener, the follower engages the shaft and translates the nut toward the head, and in response to continued rotation of the fastener, the nut engages the shaft, continues to translate toward the head, and compresses the helical washer between the toilet bowl and the nut.

[0006] Other aspects of the disclosure will become apparent by consideration of the detailed description and accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Fig. 1 is a perspective view of a fastening assembly in accordance with one aspect of the disclosure, illustrating a coil nut in an extended state.

[0008] Fig. 2 is a perspective view of the coil nut shown in Fig. 1 arranged on a threaded fastener.

[0009] Fig. 3 is a cross-sectional view of the fastening assembly shown in Fig. 1.

[0010] Fig. 4 is an exploded perspective view of the fastening assembly shown in Fig. 1.

[0011] Fig. 5 is a cross-sectional view of the fastening assembly shown in Fig. 1, illustrating the coil nut in a compressed state.

[0012] Fig. 6 is a perspective view of a threaded fastener in accordance with another aspect of the disclosure.DETAILED DESCRIPTION

[0013] Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of supporting other embodiments and being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for purpose of description and should not be regarded as limiting.Attorney Docket No. 015005-0036-W001

[0014] Figs. 1 and 2 illustrate a toilet seat hinge assembly 10 for mounting a toilet seat, or ring, and / or lid to a toilet bowl 14 (Fig. 3). The hinge assembly 10 includes a hinge post 18 and a fastening assembly 22 to secure the hinge post 18 to the toilet bowl 14. The illustrated fastening assembly 22 includes a threaded fastener 26, a coil nut 30 with a bushing 34 (Fig. 4), and a follower 38 removably coupled to the coil nut 30. Although only one hinge assembly 10 is shown, it should be readily apparent that a toilet typically includes two similar hinge assemblies 10 to mount the toilet seat and / or lid to the bowl 14. Alternatively, the hinge assembly 10 may be a platform-style hinge assembly that is secured to the toilet bowl 14 by one or more fastening assemblies 22.

[0015] With reference to Figs. 3 and 4, the illustrated hinge post 18 includes a base portion 42, a post portion 46, and a cover 50. In other embodiments, the hinge post 18 may have other configurations and / or components. The base portion 42 is configured to sit on the toilet bowl 14 and defines a recessed area 54. The recessed area 54 is bound by an upwardly-extending sidewall 58 of the base portion 42. The recessed area 54 is shaped and sized to receive portions of the threaded fastener 26 and the bushing 34 when the hinge post 18 is positioned on the toilet bowl 14. An opening 62 is formed through the base portion 42 in communication with the recessed area 54. The illustrated opening 62 is an elongated opening that receives the threaded fastener 26 to align the fastener 26 with a bore 66 (Fig. 3) in the bowl 14. The elongated opening 62 allows the position of the hinge post 18 to be adjusted relative to the fastener 26 and the bore 66. That is, the opening 62 allows the hinge post 18 to be moved relative to the bowl 14 to accommodate and compensate for different sizes of toilet bowls and seats. A series of ridges or teeth 70 is formed on an upper surface of the base portion 42 that surrounds the elongated opening 62 to increase grip and inhibit movement between the bushing 34 and the hinge post 18.

[0016] The post portion 46 includes one or more legs 74 extending perpendicularly from the base portion 42. The leg 74 defines a bore 78 for receiving a pin. The pin pivotally mounts one or more hinge leaves to the hinge post 18 to pivotally couple the toilet seat and / or lid to the hinge assembly 10. In some embodiments, the pin may be part of a slow close module that is coupled to the hinge post 18.Attorney Docket No. 015005-0036-W001

[0017] The cover 50 is coupled to the base portion 42 by a hinge 82 (e.g., a living hinge). The cover 50 is movable between an open position (Fig. 1) and a closed position. When in the open position, the cover 50 allows access to the recessed area 54 of the base portion 42. When in the closed position, the cover 50 substantially covers the recessed area 54 to provide a clean appearance for the hinge assembly 10. The cover 50 includes two bosses 86 that are configured to be received in corresponding apertures 90 in the base portion 42 when the cover 50 is closed. The bosses 86 and the apertures 90 create interference fits to releasably secure the cover 50 in the closed position. In other embodiments, the cover 50 may be coupled to the base portion 42 by other types of hinges or in other manners.

[0018] The threaded fastener 26 extends through the opening 62 in the hinge post 18 and the bore 66 in the toilet bowl 14 to secure the hinge post 18 to the bowl 14. As shown in Figs. 3 and 4, the fastener 26 defines a longitudinal axis 94 and includes a head 106 and a shaft 110. The illustrated head 106 is, for example, a conventional hex-shaped head. The shaft 110 extends from the head 106 through the bore 66 in the toilet bowl 14. In some embodiments, the shaft 110 has a diameter between approximately 3 / 16 inch and approximately 3 / 8 inch. In the illustrated embodiment, the shaft 110 has a diameter of approximately % inch. The illustrated threaded fastener 26 is composed of a plastic material, such as, for example, 30% glass filled nylon. In other embodiments, the fastener 26 may be a steel or stainless steel bolt.

[0019] With continued reference to Figs. 3 and 4, the illustrated head 106 includes a first or lower segment 118 coupled to the shaft 110 of the threaded fastener 26, a second or upper segment 122, and a middle shear segment 126 connecting the first and second segments 118, 122. The segments 118, 122, 126 are coaxially aligned along the longitudinal axis 94. The first and second segments 118, 122 have similarly-shaped outer surfaces. In the illustrated embodiment, the first and second segments 118, 122 both include hex-shaped outer surfaces that are configured to be engaged by a tool (e.g., a wrench, a pliers, etc.) to rotate the head 106 — and therefore the fastener 26 — about the longitudinal axis 94. The shear segment 126 is relatively thinner than the first and second segments 118, 122 such that the shear segment 126 has a lower torque resistance than the first and second segments 118, 122. When a predetermined amount or predetermined torque T is applied to the second segment 122, the shear segment 126 breaks, separating the second segment 122 from the first segment 118 and leaving the first segment 118Attorney Docket No. 015005-0036-W001 with the fastener 26. Such an arrangement inhibits over-tightening of the fastener 26 and removes excess material from the fastener 26 so that the cover 50 of the hinge post 18 can be closed. In other words, the shear segment 126 breaks at a predetermined torque threshold to ensure that a proper torque is applied to the fastener 26 to securely clamp the toilet seat hinge assembly 10 to the toilet bowl 14. In other embodiments, the head 106 may not include a shear segment 126.

[0020] The shaft 110 includes a first, coarse threaded region 130 and a second, fine threaded region 134. In the illustrated embodiment, the coarse threaded region 130 has 2 threads per inch (TPI), and the fine threaded region 134 has about 20 TPI. In other words, the fine threaded region 134 has approximately 10 times more threads per inch than the coarse threaded region 130. In other embodiments, the fine threaded region 134 ranges between 16 and 26 TPI. As such, the fine threaded region 134 may have approximately 8 to 13 more threads per inch than the coarse threaded region 130. As explained in further detail below, the follower 38 engages the coarse threaded region 130 to rapidly compress the coil nut 30, and a portion of the coil nut 30 engages the fine threaded region 134 to finish compressing the coil nut 30. In other embodiments, the shaft 110 of the fastener 26 only includes the second, fine threaded region 134 along the entire length of the shaft 110.

[0021] The bushing 34 may be received into the bore 66 in the toilet bowl 14, and the fastener 26 is inserted through the bushing 34 such that the bushing 34 is positioned around the shaft 110 of the fastener 26. The coil nut 30 may be composed of a plastic material such as, for example, 20% glass filled homopolymer polypropylene (HOPP). The bushing 34 includes a flange 138 formed at the upper end of the coil nut 30 and an upper section 140 below the flange 138. The upper section 140 has an outer dimension that is smaller than the opening 62 in the hinge post 18 and the bore 66 in the toilet bowl 14. The flange 138 is captured between the head 106 of the fastener 26 and the base portion 42 of the hinge post 18.

[0022] The coil nut 30 is capable of conforming to the various dimensions and shapes of mounting holes in toilet bowls. To this end, the bushing 34 includes projections 146 (Fig. 4) extending radially outward from the upper section 140. In the illustrated embodiment, the bushing 34 includes four sets of two projections 146. In other embodiments, the bushing 34 mayAttorney Docket No. 015005-0036-W001 include fewer or more projections 146. The projections 146 engage an inner surface of the mounting hole or bore 66. The projections 146 deform and conform to the shape of the bore 66 and align the bushing 34 within the bore 66. The illustrated projections 146 extend radially outward at a greater distance than the diameter of the bore 66 such that the projections 146 deflect upwardly when the bushing 34 is inserted into the bore 66. Cutouts 154 (Fig. 4) are formed in the base portion 42 adjacent the elongated opening 62 to provide clearance for the projections 146 when the bushing 34 is inserted through the opening 62.

[0023] The coil nut 30 further includes a nut 158 and a helical washer 162 extending between the nut 158 and the upper section 140. In the illustrated embodiment, the helical washer 162 of the coil nut 30 has a cylindrical shape, and therefore has a constant diameter. In other embodiments, the helical washer 162 may have a conical tapered shape or any other suitable shape. The nut 158 includes threads 166 on an inner periphery or inner surface of the nut 158. The threads 166 are configured to engage the fine threaded region 134. That is, the threads 166 correspond to the fine threaded region 134 of the shaft 110. The nut 158 also includes a quick disconnect mechanism 170 to selectively couple to the follower 38. In the illustrated embodiment, the quick disconnect mechanism 170 includes four equally spaced-apart pockets 172 on the nut 158, which engage four equally spaced-apart snap latches 173 of the follower 38. In other embodiments, the quick disconnect mechanism 170 may have other configurations, such as different numbers of pockets and snap latches, snap latches on the nut 158 and pockets on the follower 38, and or other suitable structures (e.g., hooks, magnets, pins, etc.) to releasably couple the follower 38 to the nut 158. The follower 38 disengages the nut 158 via the quick disconnect mechanism 170 when a sufficient force is exerted on the follower 38. The follower 38 also includes bulbous elements 174 on the inner periphery that are configured to engage the coarse threaded region 130 of the fastener 26.

[0024] In embodiments where the shaft 110 of the fastener 26 only includes the fine threaded region 134, the coil nut 30 is without the follower 38.

[0025] The helical washer 162 serves multiple purposes: (1) combines the bushing 34 and the nut 158 into a single unitary component, and (2) acts as a washer on the underneath side ofAttorney Docket No. 015005-0036-W001 the toilet bowl 14 to maintain the nut 158 threadably engaged with the fastener 26. The helical washer 162 is capable of elastic deformation, as explained in further detail below.

[0026] During assembly, the illustrated fastening assembly 22 facilitates rapid, top-install, top-tightened installation of the toilet seat hinge assembly 10 on the toilet bowl 14. The threaded fastener 26, the coil nut 30, and the follower 38 can be preassembled as a single unit and then inserted through the opening 62 of the hinge post 18 and into the bore 66 of the toilet bowl 14 to secure the hinge post 18 to the bowl 14. Specifically, the fastener 26 and the coil nut 30 are coupled together with the coil nut 30 in an extended state, or first state (Fig. 3). That is, the nut follower 38 (which is coupled to the nut 158) is engaged with the coarse threaded region 130 of the fastener 26 in the extended state. Although the outer dimension of the helical washer 162 may be larger than the inner dimension of the opening 62 and the bore 66, the helical washer 162 may be inserted through the opening 62 and the bore 66 by rotating the coil nut 30 through the opening 62 and the bore 66. Specifically, the follower 38 and the nut 158 pass through the opening 62 and the bore 66, and then the helical washer 162 is rotated as it slides through the opening 62 and the bore 66 until the flange 138 is received within the recessed area 54. As such, the nut 158 and the helical washer 162 (along with the fastener 26) are inserted via the top-side of the toilet bowl 14 — meaning that a user is not required to reach under / behind the toilet bowl 14 to install the toilet seat hinge assembly 10. Also, the projections 146 may engage the bore 66 in the toilet bowl 14.

[0027] At this point, a user engages the head 106 of the fastener with a tool to begin rotating the fastener 26 relative to the coil nut 30. The flange 138 is received within the recessed area 54, thereby inhibiting rotation of the entire coil nut 30 such that a user does not need to grasp and hold the coil nut 30 when rotating the fastener 26. As the fastener 26 is rotated, the bulbous elements 174 of the follower 38 mesh with the coarse threaded region 130 of the shaft 110 and the follower 38 translates along the shaft 110 toward the head 106 (i.e., toward a compressed state). The threads 166 of the nut 158, however, do not engage the coarse threaded region 130 because the coarse threaded region 130 has an outer diameter that is less than an outer diameter of the fine threaded region 134 (and an inner diameter of the nut 158). Nonetheless, the nut 158 translates along the shaft 110 as the follower 38 threads along the coarse threaded region 130 until the nut 158 threadably engages the fine threaded region 134. Here, the bulbous elementsAttorney Docket No. 015005-0036-W001174 maintain the follower 38 with the coarse threaded region 130 and the quick disconnect mechanism 170 permits the follower 38 to decouple from the nut 158 as the nut 1 8 continues to translate along the fine threaded region 134 during rotation of the fastener 26. Subsequently, the follower 38 may fall off the fastener 26 altogether under gravity. Alternatively, the follower 38 may remain connected to the coarse threaded region 130. The helical washer 162 continues to compress as the fastener 26 rotates and the nut 158 translates along the shaft 110 of the fastener 26 toward the toilet bowl 14. As the helical washer 162 compresses, the helical washer 162 simultaneously expands radially outward. Therefore, the coils of the helical washer 162 are stacked relative to each other and collectively form an outer dimension that is larger than bore 66 of the toilet bowl 14 to inhibit the fastening assembly 22 from being decoupled from the toilet bowl 14. When the coils of the helical washer 162 are stacked relative to each other, the coil nut 30 is in the compressed state, or second state.

[0028] In embodiments where the threaded fastener 26 includes the shear segment 126, the user continues to rotate the fastener 26 until the shear segment 126 breaks to secure the hinge assembly 10 in place. The fastening assembly 22 is advantageous as the arrangement allows the fastening assembly 22 to be top-installed and top-tightened in restricted areas, such as on toilet bowls with blind bores. In addition, the coarse threaded region 130 allows the fastening assembly 22 to initially be rapidly tightened before the nut 158 engages the fine threaded region 134.

[0029] Fig. 6 illustrates another threaded fastener 26a that may be incorporated with the toilet seat hinge assembly 10 in place of the threaded fastener 26 of Figs. 1-5. The threaded fastener 26a is substantially similar to the threaded fastener 26 of Figs. 1-5; therefore like structure will be identified by like reference number plus “a” and only the differences will be discussed hereafter. A shaft 110a of the threaded fastener 26a includes a first, coarse threaded region 130a and a second, fine threaded region 134a. In the illustrated embodiment, the coarse threaded region 130a has 1 TPI and the fine threaded region 134a has about 20 TPI.

[0030] Although the disclosure has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the disclosure as described. For example, in other scenarios, theAttorney Docket No. 015005-0036-W001 fastening assembly 22 may be used to secure other objects together, rather than a toilet seat hinge. In such embodiments, the fastening assembly 22 may still be installed from one side of the objects, rapidly tightened with the coarse threaded region 130, 130a and the follower 38, and inhibited from being overtightened by the shear segment 126, 126a. In some embodiments, the fastening assembly 22 may not include the shear segment 126, 126a and may instead include a conventional fastener or bolt head.

[0031] Various features of the disclosure are set forth in the following claims.

Claims

Attorney Docket No. 015005-0036-W001CLAIMSWhat is claimed is:

1. A fastening assembly for mounting a toilet seat to a toilet bowl, the fastening assembly comprising: a nut; a follower coupled to the nut; and a fastener including a head and a shaft configured to extend into a bore of the toilet bowl, the shaft having a first threaded region and a second threaded region that is different from the first threaded region, wherein the follower engages the first threaded region and translates the nut toward the second threaded region in response to rotation of the fastener, and wherein when the nut reaches the second threaded region, the nut engages the second threaded region and translates toward the head in response to rotation of the fastener.

2. The fastening assembly of claim 1, wherein when the nut engages the second threaded region and translates toward the head, the follower decouples from the nut.

3. The fastening assembly of claim 1, further comprising a quick disconnect mechanism that couples the follower to the nut.

4. The fastening assembly of claim 1, wherein the first threaded region is a coarse threaded region and the second threaded region is a fine threaded region.

5. The fastening assembly of claim 4, wherein the follower includes bulbous elements that engage the coarse threaded region, and wherein the nut includes threads that engage the fine threaded region.Attorney Docket No. 015005-0036-W0016. The fastening assembly of claim 1, wherein the nut is connected to a flange that is configured to be received within a hinge post of the toilet seat to inhibit rotation of the nut when the fastener is rotated.

7. The fastening assembly of claim 6, further comprising a helical washer that connects the flange to the nut, wherein the helical washer is compressed in response to the nut translating along the shaft of the fastener toward the head of the fastener.

8. The fastening assembly of claim 7, wherein the helical washer is configured to be disposed between the toilet bowl and the nut when the nut is coupled to the fastener.

9. The fastening assembly of claim 1, wherein the head includes a first segment coupled to the shaft, a second segment configured to be engaged by a tool to rotate the fastener, and a shear segment connecting the first and second segments, the shear segment having a lower torque resistance than the first and second segments such that the shear segment breaks when a torque applied to the second segment reaches a predetermined amount.

10. The fastening assembly of claim 9, wherein the first segment is also configured to be engaged by the tool to rotate the fastener.

11. The fastening assembly of claim 9, wherein the first segment and the second segment of the fastener have similarly-shaped outer surfaces.

12. The fastening assembly of claim 11, wherein the outer surfaces of the first and second segments are hex-shaped.

13. A fastening assembly for mounting a toilet seat to a toilet bowl, the fastening assembly comprising: a fastener including a head and a shaft configured to extend into a bore of the toilet bowl; andAttorney Docket No. 015005-0036-W001 a coil nut surrounding the shaft and including a flange, a nut, and a helical washer disposed between the flange and the nut, wherein, in response to rotation of the fastener, the nut engages the shaft and translates toward the head, compressing the helical washer between the toilet bowl and the nut.

14. The fastening assembly of claim 13, wherein the helical washer deforms radially outward when being compressed and defines an outer dimension that is larger than the bore to inhibit removal of the fastening assembly though the bore.

15. A fastening assembly for mounting a toilet seat to a toilet bowl, the fastening assembly comprising: a fastener including a head and a shaft configured to extend into a bore of the toilet bowl; a coil nut surrounding the shaft and including a flange, a nut, and a helical washer disposed between the flange and the nut; and a follower coupled to the nut, wherein, in response to initial rotation of the fastener, the follower engages the shaft and translates the nut toward the head, and in response to continued rotation of the fastener, the nut engages the shaft, continues to translate toward the head, and compresses the helical washer between the toilet bowl and the nut.

16. The fastening assembly of claim 15, wherein after the nut engages the shaft, the follower decouples from the nut.

17. The fastening assembly of claim 15, wherein the helical washer deforms radially outward when being compressed and defines an outer dimension that is larger than the bore to inhibit removal of the fastening assembly through the bore.

18. The fastening assembly of claim 15, wherein the follower engages a coarse threaded region of the shaft for initially tightening the fastening assembly before the nut engages the shaft.Attorney Docket No. 015005-0036-W00119. The fastening assembly of claim 15, further comprising a quick disconnect mechanism that couples the follower to the nut.

20. The fastening assembly of claim 15, wherein the head includes a first segment coupled to the shaft, a second segment configured to be engaged by a tool to rotate the fastener, and a shear segment connecting the first and second segments, the shear segment having a lower torque resistance than the first and second segments such that the shear segment breaks when a torque applied to the second segment reaches a predetermined amount.

Citation Information

Patent Citations

  • Toilet seat hinge assembly

    US20130340154A1