GB2316729A

GB2316729A - Expanding wall plug

Info

Publication number: GB2316729A
Application number: GB9618275A
Authority: GB
Inventors: Ming-Hsin Wu
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-09-02
Filing date: 1996-09-02
Publication date: 1998-03-04
Also published as: GB9618275D0

Abstract

The screw-threaded bolt (1) has two (or one) lugs (13) projecting from its head (12), expandable shells (2) each having a tapered portion (23) provided with longitudinal lugs (24), transverse slots (21) and longitudinal slots (21), and a locating sleeve (3) having longitudinal slots (31) to receive the lugs (24) of the adjacent expandable shell (2), so that rotation of a nut (4) on the bolt (1) to expand the shells (2) and the locating sleeve (3), also causes the lugs (13) on the bolthead (12) to be located in the transverse slots (21) to prevent reverse movement of the bolt.

Description

EXPANDING WALL PLUG The present invention relates to expanding wall plugs, and relates more particularly to a new design of expanding wall plug with anti-skid means which is practical for use in any of a variety of walls and, which has means to stop itself from being moved axially or rotated.

Figure 1 shows an expanding wall plug according to the prior art. This structure of expanding wall plug is comprised of a screw bolt 10, an expansion barrel 20, a nut 30, and a washer 40. The expansion barrel 20 has a plurality of longitudinal splits 201 at one end. When the screw bolt 10 is inserted through the expansion barrel 20 and the washer 40 and screwed up with the nut 30, the head 101 is forced into the split end of the expansion barrel 20, thereby causing the split end of the expansion barrel 20 to expand and to be firmly secured in the wall. Because the head 101 is forced into the inside of the split end of the expansion barrel 20, a gap is left between the outside surface of the wall and the head 101 of the screw bolt 10.

Therefore, the screw bolt 10 tends to displace backwards after its installation. During the installation of the expanding wall plug in a wall to secure a sink, the screw bolt 10 must be held in place so that the nut 30 can be positively threaded onto the screw bolt 10. When the expansion barrel 20 is installed, it tends to be turned with the screw bolt 10 in the hole of the wall when the nut 30 is rotated. Furthermore, because the expansion barrel 20 is secured to the wall by the split end, i.e., the expansion barrel 20 has only one end secured to the wall, it tends to be forced to displace.

This problem is more apparent when the expanding wall plug is installed in a hollow brick wall or an earth wall.

The present invention has been accomplished to provide an expanding wall plug which eliminates the aforesaid drawbacks. According to one aspect of the present invention, the expanding wall plug is comprised of a screw bolt, a plurality of expansion shells, a locating socket, and a nut. The screw bolt has keys raised from the periphery of the head for forcing the expansion shells and the locating socket to expand. The expansion shells have transverse locating slots for holding the keys of the screw bolt to stop the screw bolt from reverse movement. According to another aspect of the present invention, the locating socket has a plain barrel at the rear end, and wedge blocks raised from the plain barrel and forced into engagement with the wall to stop the locating socket from rotary motion relative to the screw bolt. According to still another aspect of the present invention, the expansion shells are connected in series, having a respective outer thread adapted for engaging the wall structure, longitudinal wedge blocks and longitudinal slots alternatively arranged around the periphery for permitting the expansion shells to be connected one another in a series and respectively expanded by the compression force of the head of the screw bolt for positive positioning in the wall.

An embodiment of the present invention will be described by way example and with reference to the accompanying drawings,in which Fig. 2 is an exploded view of an expanding wall plug according to the present invention; Fig. 3 is an elevational assembly view of the expanding wall plug shown in Figure 2; Fig. 4 is similar to Figure 3 but showing the expansion shells and the locating socket expanded; Fig. 5 is an installation example of the present invention, showing the expanding wall plug installed in a hollow brick; and Fig. 6 is another installation example of the present invention, showing the use of the expanding wall plug with a sink.

Referring to Figure 2, an expanding wall plug in accordance with the present invention is generally comprised of a screw bolt 1, a plurality of expansion shells 2, a locating socket 3, a washer 41, and a nut 4.

The screw bolt 1 matches with the nut 4 to suspend a suspending object such as a sink or a machine base, having a head 12 at one end, two keys 13 symmetrically raised from the periphery of the head 12, and an outer thread 11 around the periphery. Each of the expansion shells 2 comprises an outer thread 22 at one end, a tapered locating portion 23 at an opposite end, two longitudinal wedge blocks 24 raised from the periphery of the tapered locating portion 23 at two opposite sides, two transverse slots 211 in the middle, and two longitudinal slots 21 respectively and longitudinally extending from the transverse slots 211 to the end remote from the tapered locating portion 23. The locating socket 3 is a hollow, stub tube, comprising a plain barrel 33 at one end, two wedge blocks 34 raised from the plain barrel 33, an outer thread 32 at an opposite end, and two longitudinal slots 31 longitudinally extending through the outer threads 32 to the end remote from the plain barrel 33.

Referring to Figures 3 and 4, when the screw bolt 1 is inserted through the expansion shells 2 and the locating socket 3, the washer 41 is mounted around the screw bolt 1, and the nut 4 is threaded onto the outer thread 11 of the screw bolt 1, permitting the keys 13 of the head 12 of the screw bolt 1 to be inserted into the longitudinal slots 21 of one expansion shell 2, the wedge blocks 24 of one expansion shell 2 to be respectively inserted into the longitudinal slots 21 of another or the longitudinal slots 31 of the locating socket 3 (see Figure 3). When expanding wall plug is forced into the wall or a hole in the wall, the nut 4 is rotated, causing the screw bolt 1 to move forwards, and therefore the expansion shells 2 and the locating socket 3 are forced to expand (see Figure 4). When the keys 13 of the screw bolt 1 are moved into the transverse slots 211 of the first expansion shell 2, the head 12 of the screw bolt 1 becomes firmly retained in place and prohibited from a backward displacement (see Figure 4).

Because the wedge blocks 34 of the locating socket 3 are forced into engagement with the wall or the periphery of the hole in the wall, the rotary motion of the nut 4 does not cause the locating socket 3 and the expansion shells 2 to be turned with the screw bolt 1.

Figure 5 shows the expanding wall plug installed in a hollow brick 5. Because the expanding wall plug is comprised of a plurality of expansion shells 2 longitudinally connected in series to the locating socket 3, the suspension of the rear end of the expanding wall plug in a hollow space inside the hollow brick 5 does not affect the positioning of the expanding wall plug, i.e., the outer threads 21 of the embedded expansion shells 2 and the outer thread 31 of the locating socket 3 are still maintained in engagement the the solid structure of the hollow brick positively.

Referring to Figure 6, when the expanding wall plug is installed in a wall to hold a sink 6, the outer thread 11 of the screw bolt 1 is inserted through the hanging hole 61 in the sink 6, for permitting the washer 41 and the nut 4 to be positively and quickly fastened to the screw bolt 1 to secure the sink 6 in place.

The screw bolt 1 and the nut 4 are preferably made from metal. However, the expansion shells 2 and the locating socket 3 can be made from metal, or suitable plastic material.

While only one embodiment of the present invention has been shown and described, it will be understood that various modifications and changes could be made thereunto without departing from the spirit and scope of the invention disclosed. For example, the head 12 of the screw bolt 1 can be made having only one key 13, and the expansion shell 2 or locating socket 3 is made having only one longitudinal slot 21 or 31 and one wedge block 24 or 34 for engagement.

Claims

1. An expanding wall plug comprising a screw-threaded bolt having a head from which projects at least one key extending longitudinally of the bolt, at least one expansion shell mounted on the bolt one end extent of which is provided, for the or each key on the head of the bolt, with a longitudinal slot extending from the one end of the expansion shell and feeding into a transverse locating slot intermediate the length of the expansion shell, the other end extent of the expansion shell tapering towards the other end thereof and being provided with at least one longitudinal wedge block thereon, a locating socket mounted on the bolt, one end extent of said locating socket adjacent the other end of an expansion shell having, for the or each wedge block on the expansion shell, a longitudinal slot therein, and a nut on the bolt for reacting against the other end of the locating socket, rotation of the nut, in use, causing axial movement of the bolt relative to the or each expansion shell and the locating socket whereby the head of the bolt is drawn into the one end extent of the, or of the endmost, expansion shell with the or each key located in the associated longitudinal slot and thence in the associated transverse slot to prevent reverse movement of the bolt.

2. An expanding wall plug as claimed in claim 1 in which the other end extent of the locating socket comprises a plain barrel upstanding from which is at least one longitudinal wedge block.

3. An expanding wall plug as claimed in claim 1 or claim 2 in which the one end extent of the or each expansion shell is externally threaded.

4. An expanding wall plug as claimed in any one of claims 1 to 3 in which there are a pair of opposed keys on the head of the bolt, the or each expansion shell including a pair of opposed longitudinal slots in the one end extent thereof, and a pair of opposed wedge blocks on the other end extent thereof, the slots and wedge blocks being equi-spaced around the expansion shell.

5. An expanding wall plug comprising a plurality of expansion shells in series, one end expansion shell of the series receiving therein the head of the bolt and the tapering other end extent of the other end expansion shell of the series being received within the locating socket.

6. An expanding wall plug as claimed in any one of claims 1 to 5 and including a washer mounted on the bolt to react between the nut and the other end of the locating socket.

7. An expanding wall plug as claimed in any one of claims 1 to 6 in which the or each expansion shell and the locating socket are each of a plastics material.

8. An expanding wall plug substantially as described with reference to and as illustrated by Figs 2 to 6 of the accompanying drawings.