Floating fastener

A floating fastener includes a mounting base member affixed to a first panel member and including a relatively smaller lower outer perimeter, a relatively larger upper outer perimeter, an outer stop flange extending around a top side of the upper outer perimeter, a bottom mounting neck and a cushion ring mounted in a locating groove around the lower outer perimeter, a rotary fastening member inserted through the mounting base member for locking a second panel member to the first panel member through a rotary motion, and a cap member affixed to a head of the rotary fastening member outside the mounting base member and having an inside bottom stop flange coupled to the mounting base member and axially slidable along the upper and lower outer perimeters and stoppable at the bottom side of the outer stop flange of the mounting base member.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to fastener means for detachably securing two panel members together, and more particularly to a floating fastener consisting of a mounting base member, a rotary fastening member and a cap member, which facilitates mounting and dismounting without causing any component damage.

2. Description of the Related Art

When joining panel members, a fastening device formed of a lock screw, a rotary knob and a washer may be used. During application, the lock screw, rotary knob and washer of each fastening device are assembled and then mounted at a first panel member. When fastening the first panel member to a second panel member, rotate the rotary knob of each fastening device to drive the respective lock screw into a respective mounting screw hole at the second panel member, and then use a hand tool to fasten tight the lock screw. These fastening devices are widely used in server racks for telecommunication, industrial computers, machine tools, and other situations where multiple panel members are to be fastened in a stack. Further, a floating fastener formed of a cap member, a rotary fastening member, a spring member and a socket member has also been created for detachably fastening two panel members together by: affixing the socket member of the floating fastener to a mounting center opening of one panel member and then threading the spring-loaded screw member into a mounting screw hole of the other panel member. After separation between the two panel members, the floating fastener is kept secured to the respective panel member.

FIG. 10illustrates a floating fastener according to the prior art. As illustrated, this design of floating fastener comprises a mounting base member A, which comprises a stepped center opening A0having an annular step A3on the middle, a bottom mounting flange A1affixed to a panel member B and an outside stop flange A2extending around the periphery of the top side thereof, a rotary fastening member C1inserted through the mounting base member A, a spring member C11mounted around the rotary fastening member C1and stopped between the head of the rotary fastening member C1and the outside stop flange A2of the mounting base member A, and a cap member C affixed to the head of the rotary fastening member C1. The cap member C comprises an inside bottom stop flange C3axially slidably coupled to the mounting base member A, and a plurality of longitudinal crevices C2equiangularly spaced around the periphery thereof and longitudinally cut through the inside bottom stop flange C3for enabling the inside bottom stop flange C3to be radially flexibly expanded and then coupled to the periphery of the mounting base member A. This design of floating fastener still has drawbacks as follows:

1. When moving the inside bottom stop flange C3of the cap member C downwardly over the outside stop flange A2of the mounting base member A to have the inside bottom stop flange C3be coupled to the periphery of the mounting base member A after installation of the mounting base member A in the panel member B, the spring member C11imparts a pressure to the cap member C in direction away from the mounting base member A, complicating the installation, and the mounting base member A may be accidentally biased relative to the mounting base member A or forced away from the mounting base member A.

2. When forcing the inside bottom stop flange C3of the cap member C downwardly over the outside stop flange A2of the mounting base member A, the inside bottom stop flange C3may break or be permanently deformed.

3. The design of the longitudinal crevices C2weakens the structural strength of the cap member C.

Therefore, it is desirable to provide an improvement design of floating fastener, which facilitates quick and accurate installation, prevents component damage.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide a floating fastener for detachably fastening two panel members together, which has the advantages of ease of use, high installation reliability and high positioning accuracy.

To achieve this and other objects of the present invention, a floating fastener of the present invention comprises a mounting base member, a rotary fastening member, and a cap member. The mounting base member comprises a center opening extending through opposing top and bottom sides thereof, a bottom mounting neck downwardly extended from the bottom side thereof and affixed to said first panel member, a relatively smaller lower outer perimeter and a relatively larger upper perimeter extending around the center opening at different elevations, a cushion ring mounted in the locating groove around said lower outer perimeter, and an outer stop flange extending around a top side of the upper outer perimeter. The rotary fastening member is inserted through the mounting base member for locking a second panel member to the first panel member through a rotary motion, having a head thereof suspending outside the mounting base member. The cap member is affixed to the head of the rotary fastening member outside the mounting base member, having an inside bottom stop flange coupled to the mounting base member and axially slidable along the upper and lower outer perimeters and stoppable at the bottom side of the outer stop flange of the mounting base member.

Further, the mounting base member further comprises a tapered outer surface portion connected between the lower outer perimeter and the upper outer perimeter a locating groove extending around the lower outer perimeter, and sloping downwardly inwards in direction from the upper outer perimeter toward the lower outer perimeter.

Preferably, the cap member further comprises a grip formed integral with and extending around the periphery thereof. The grip comprises a plurality of tool gripping planes and finger gripping portions alternatively arranged around the periphery of said cap member.

Further, each finger gripping portion can be selectively made in a series of longitudinal teeth, an embossed pattern, an array of raised portions, or any anti-slip design for the gripping of the fingers. Further, the tool gripping planes of the cap member can be selectively made in a square configuration, hexagonal configuration, polygonal configuration, recessed square configuration, recessed hexagonal configuration or recessed polygonal configuration for the positioning of an open-end wrench, socket wrench, ratchet wrench, spanner or any other hand tool to rotate the cap member and the rotary fastening member relative to the mounting base member.

Further, the center opening of the mounting base member can be made in the form of a stepped hole having relatively larger upper part that defines an inside chamber and an annular step so that a spring member can be mounted around the rotary fastening member and stopped between the flat bottom wall of the head of the rotary fastening member and the annular step of the mounting base member.

Preferably, the mounting base member further comprises a mounting groove extending around the periphery of the bottom mounting neck for enabling the mounting neck to be positively and accurately riveted, bonded or welded to a mounting hole in the first panel member.

Further, the outer stop flange of the mounting base member has a diameter larger than the diameter of the upper outer perimeter and the outer diameter of the cushion ring. Before mounting the mounting base member in the first panel member, the cap member can be lowered to force the inside bottom stop flange downwardly over the cushion ring and to have the inside bottom stop flange be temporarily stopped below the cushion ring, enabling the floating fastener to be conveniently picked up by a vacuum suction device and then delivered to the first panel member for installation without causing component displacement.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring toFIGS. 1-4, a floating fastener in accordance with the present invention is shown. The floating fastener comprises a mounting base member1, a rotary fastening member2, and a cap member3.

The mounting base member1is an open-ended cylindrical member comprising a center opening10axially extending through opposing top and bottom sides thereof, a lower outer perimeter11extending around a lower part of the center opening10, an upper outer perimeter12extending around an upper part of the center opening10and having an outer diameter larger than the lower outer perimeter11, a tapered outer surface portion111connected between the lower outer perimeter11and the upper outer perimeter12, a bottom mounting neck13downwardly extended from the bottom side thereof around the center opening10, a mounting groove131extending around the periphery of the bottom mounting neck13, a locating groove14extending around the lower outer perimeter11near the bottom mounting neck13, a cushion ring141mounted in the locating groove14around the lower outer perimeter11and defining a tapered top guide surface portion1411and a bottom bearing surface portion1412, and an outer stop flange15extending around a top side of the upper outer perimeter12. The outer stop flange15has a diameter larger than the diameter of the upper outer perimeter12and the outer diameter of the cushion ring141, defining a tapered top thrust surface portion151and a flat bottom stop surface portion152.

The rotary fastening member2comprises a head21suspending above the mounting base member1, an engagement portion212made in the form of an array of teeth, an embossed pattern, an array of tiny protrusions or any of a variety of other positioning designs and disposed around the periphery of the head21, a shoulder22perpendicularly downwardly extended from a center area of a flat bottom wall211of the head21and inserted into the center opening10of the mounting base member1, a screw rod23axially extended from a bottom end of the shoulder22opposite to the head21in a concentric manner and defining a spiral outer thread231around the periphery thereof, and a tool-positioning means (not shown) formed in an opposing top wall of the head21for the positioning of a hand tool for rotating the rotary fastening member2. The tool-positioning means can be made in the form of a straight slot, crossed slot, star shaped slot or hexagonal slot, or in the form of a straight block, crossed block, star shaped block or hexagonal block.

The cap member3comprises an accommodation open space30surrounded by an inside wall thereof and extending through opposing top and bottom sides thereof, an inside locating groove301extending around the inside wall near the top side for engagement with the engagement portion212of the rotary fastening member2, an inside bottom stop flange31extended around the inside wall at a bottom side of the accommodation open space30, and a grip32formed integral with and extending around the periphery thereof. The grip32comprises a plurality of tool gripping planes321and finger gripping portions33alternatively arranged around the periphery of the cap member3.

When assembling the floating fastener, insert the screw rod23and shoulder22of the rotary fastening member2into the center opening10of the mounting base member1to let the head21of the rotary fastening member2be disposed outside the mounting base member1, and then cap the cap member3on the head21of the rotary fastening member2to force the inside locating groove301of the cap member3into engagement with the engagement portion212, and then lower the cap member3to move the inside bottom stop flange31of the cap member3over the tapered top thrust surface portion151of the outer stop flange15of the mounting base member1by force, enabling the inside bottom stop flange31of the cap member3to be slidably coupled to the mounting base member1and axially movable relative to the mounting base member1along the lower outer perimeter11, tapered outer surface portion111and upper outer perimeter12of the mounting base member1below the outer stop flange15, then lower the cap member3to move the inside bottom stop flange31of the cap member3downwardly over the tapered top guide surface portion1411and bottom bearing surface portion1412of the cushion ring141in the locating groove14around the lower outer perimeter11. Thus, the mounting base member1, the rotary fastening member2and the cap member3are assembled, forming the desired floating fastener.

Further, in this preferred embodiment, the mounting base member1and the rotary fastening member2are metal members of one-piece design. Further, the cap member3can be directly molded on the head21of the rotary fastening member2by insert molding. Alternatively, the rotary fastening member2and the cap member3can be separately made and then fastened together by forcing the engagement portion212of the rotary fastening member2into friction engagement with the inside locating groove301of the cap member3. Further, in this preferred embodiment, the inside bottom stop flange31of the cap member3is stopped below the flat bottom stop surface portion122of the outer stop flange15of the mounting base member1to prohibit the rotary fastening member2from escaping out of the mounting base member1. However, this design of preventing the rotary fastening member2from escaping out of the mounting base member1is not a limitation. C-shaped retainer, ring cushion or any other stoppage device can be used and mounted between the mounting base member1and the rotary fastening member2to let the rotary fastening member2be moved with the cap member3axially relative to the mounting base member1and prohibit the rotary fastening member2from falling out of the mounting base member1.

Further, the length (vertical height) of the upper outer perimeter12of the mounting base member1is shorter than the length (vertical height) of the lower outer perimeter11; the tapered outer surface portion111of the mounting base member1slopes downwardly inwardly in direction from the upper outer perimeter12toward the lower outer perimeter11. Further, the mounting base member1, the rotary fastening member2and the cap member3can be conveniently assembled together without loading a spring member, preventing spring resistance and avoiding the rotary fastening member2and the cap member3from being forced out of the mounting base member1accidentally by spring force during the assembly process. Further, the cap member3is a one piece member having a high structural strength. Further, the inner and outer edges of the inside bottom stop flange31of the cap member3are preferably beveled so that the inside bottom stop flange31can be conveniently moved over the tapered outer surface portion111of the mounting base member1and the tapered top guide surface portion1411and bottom bearing surface portion1412of the cushion ring141without less effort and without causing damage to the cap member3.

Further, the tool gripping planes321of the grip32can be designed to provide a square, hexagonal or any other polygonal configuration, or a recessed square, hexagonal or any other polygonal configuration for the positioning of an open-end wrench, socket wrench, ratchet wrench, spanner or any other hand tool to rotate the cap member3and the rotary fastening member2relative to the mounting base member1. Further, the finger gripping portions33are respectively disposed between each two adjacent tool gripping planes321. Further, each finger gripping portion33can be made in the form of a series of longitudinal teeth, an embossed pattern, an array of raised portions, or any anti-slip design for the gripping of the fingers and for enabling the cap member3and the rotary fastening member2to be conveniently rotated relative to the mounting base member1by hand.

Referring toFIGS. 5-8andFIGS. 2 and 4again, the floating fastener can be used in a telecommunication server rack, computer server, machine tool, board set structure, cabinet or keyboard rack, or other situations where multiple panel members are to be fastened in a stack. For example, the floating fastener can be installed in a first panel member4in a server case to detachably fasten a second panel member5to the first panel member4, wherein the server case houses a motherboard, power supply device, data access equipment, interface cards and/or other electronic devices. When installing the floating fastener in the first panel member4, lower the cap member3to move the inside bottom stop flange31of the cap member3downwardly over the cushion ring141(seeFIG. 5). Thereafter, insert the bottom mounting neck13of the mounting base member1into a mounting hole41of the first panel member4, enabling the mounting groove131of the bottom mounting neck13of the mounting base member1to be riveted, bonded or welded to the first panel member4positively and accurately (seeFIG. 6). After installation of the floating fastener in the first panel member4, the first panel member4attached to the second panel member5to keep the mounting hole41of the first panel member4in axial alignment with a mounting screw hole51of the second panel member5(seeFIG. 7), and then lower the cap member3relative to the mounting base member1and rotate the cap member3to drive the spiral outer thread231of the screw rod23of the rotary fastening member2into the mounting screw hole51of the second panel member5(seeFIG. 8). When threading the spiral outer thread231of the screw rod23of the rotary fastening member2into the mounting screw hole51of the second panel member5, the inside bottom stop flange31of the cap member3is moved downwardly along the lower outer perimeter11over the tapered top guide surface portion1411of the cushion ring141to the bottom side of the bottom bearing surface portion1412, and thus threading the spiral outer thread231into the mounting screw hole51does not receive any resistance from the cap member3.

Further, during the aforesaid installation procedure, the user can grip the finger gripping portions33of the cap member3with the fingers and then rotate the cap member3and the rotary fastening member2with the hand to thread the spiral outer thread231of the screw rod23into the mounting screw hole51of the second panel member5, and then use a power hand tool, or a hand tool (open-end wrench, spanner, ratchet wrench, etc.) to fasten tight the rotary fastening member2. By means of directly rotating the cap member3with the bare hand to drive the screw rod23of the rotary fastening member2into the mounting screw hole51of the second panel member5at the initial stage, the screw rod23of the rotary fastening member2can be accurately fastened to the mounting screw hole51of the second panel member5without causing thread damage. After the screw rod23of the rotary fastening member2has been accurately fastened to the mounting screw hole51of the second panel member5, the cap member3can then be rotated with a power hand tool or hand tool to fasten tight the screw rod23of the rotary fastening member2, thereby positively locking the first panel member4to the second panel member5.

When going to remove the first panel member4from the second panel member5, grip the finger gripping portions33of the grip32of the cap member3with the fingers and then rotate the cap member3in the reversed direction to disengage the screw rod23of the rotary fastening member2from the mounting screw hole51of the second panel member5. When disengaging the screw rod23of the rotary fastening member2from the mounting screw hole51of the second panel member5, the inside bottom stop flange31of the cap member3is stopped at the bottom side of the bottom bearing surface portion1412of the cushion ring141, prohibiting the rotary fastening member2from retracting into the center opening10of the mounting base member1. As stated above, subject to the design of the finger gripping portions33of the grip32of the cap member3, the user can rotate the cap member3directly with the fingers to disengage the screw rod23of the rotary fastening member2from the mounting screw hole51of the second panel member5, allowing the first panel member4to be rapidly detached from the second panel member5. The user can also attach a power hand tool or hand tool (open-end wrench, spanner, ratchet wrench, etc.) to the tool gripping portions321of the grip32of the cap member3, and then operate the power hand tool or hand tool to rotate the cap member3, disengaging the screw rod23of the rotary fastening member2from the mounting screw hole51of the second panel member5. Thus, either with the fingers or by means of a power hand tool or hand tool, the user can conveniently disengage the screw rod23of the rotary fastening member2from the mounting screw hole51of the second panel member5with less effort.

After detached the first panel member4from the second panel member5, the user can pull the cap member3to move the inside bottom top flange31upwardly over the cushion ring141to the lower outer perimeter11and then the upper outer perimeter12via the tapered outer surface portion111, and thus, the inside bottom stop flange31of the cap member3can be stopped at the bottom side of the flat bottom stop surface portion152of the outer stop flange15. Further, the aperture diameter of the inside bottom stop flange31is approximately equal to the outer diameter of the upper outer perimeter12of the mounting base member1, thus, the inside bottom stop flange31can be temporarily positioned on the upper outer perimeter12, enabling the screw rod23of the rotary fastening member2to be suspended inside the center opening10of the mounting base member1.

Referring toFIG. 9andFIGS. 2,3,4and6again, the center opening10of the mounting base member1can be a stepped hole having relatively larger upper part that defines an inside chamber101and an annular step102. Further, a spring member24can be sleeved onto the screw rod23and shoulder22of the rotary fastening member2and stopped between the flat bottom wall211of the head21of the rotary fastening member2and the annular step102of the mounting base member1to push the head21of the rotary fastening member2in direction away from the mounting base member1.

In general, the invention provides a floating fastener, which comprises a mounting base member1affixed to a first panel member4, a rotary fastening member2adapted for fastening to a second panel member5to lock the first panel member4to the second panel member5, and a cap member3, wherein the mounting base member1comprises a center opening10axially extending through opposing top and bottom sides thereof, a relatively smaller lower outer perimeter11, a relatively larger upper outer perimeter12, a bottom mounting neck13, and a cushion ring141mounted in a locating groove14around the lower outer perimeter11; the rotary fastening member2comprises a head21suspending above the mounting base member1, an engagement portion212extending around the periphery of the head21, a shoulder22perpendicularly downwardly extended from a center area of a flat bottom wall211of the head21and inserted into the center opening10of the mounting base member1, and a screw rod23axially extended from a bottom end of the shoulder22opposite to the head21in a concentric manner; the cap member3comprises an accommodation open space30surrounded by an inside wall thereof and extending through opposing top and bottom sides thereof, an inside locating groove301extending around the inside wall near the top side and forced into engagement with the engagement portion212of the rotary fastening member2, an inside bottom stop flange31extended around the inside wall at a bottom side of the accommodation open space30, and a grip32formed integral with and extending around the periphery thereof and comprising a plurality of tool gripping planes321and finger gripping portions33alternatively arranged around the periphery of the cap member3. Through the tool gripping planes321and finger gripping portions33of the grip32, the user can rotate the cap member3directly with the fingers or by means of a hand tool or power hand tool to drive the screw rod23into or out of a mounting screw hole51of the second panel member5.