US3643909A

US3643909A - Plastic plugs for use in concrete forms

Info

Publication number: US3643909A
Application number: US850493A
Authority: US
Inventors: Louis Philippe Brosseau
Original assignee: Formex Ltd
Current assignee: Formex Ltd
Priority date: 1969-08-15
Filing date: 1969-08-15
Publication date: 1972-02-22
Anticipated expiration: 1989-02-22

Abstract

A plastic plug for use with a tie bar of concrete wall forms which is made of a plastic frustoconical body having an outer larger end intended to be applied against the inner surface of a form panel and having an inner smaller end that is embedded in the concrete of the wall. The plastic body is formed on the inside with a longitudinal through passage having a shape and size to slidably and snugly receive one end of a tie bar. The inner end of the body is closed but for the opening created by the passage so as to prevent entry of concrete inside the body. The outer end of the body has a circumferential sealing flange intended to be applied against the inner surface of a form panel to prevent entry of concrete inside the plug body. In combination with this plug, a flat tie bar for holding concrete form panels in position and formed at one end with a pair of notches each provided along one of the two edges of the bar and opposite one another. A resilient ring pressed into the notches for abutment by the plug, said notches and ring being spaced from the end of the bar a distance such that the plug outer surface and the sealing flange may be slightly pressed, in use against the inner surface of a form panel.

Description

United States Patent Brosseau 1 Feb. 22, 1972 [54] PLASTIC PLUGS FOR USE IN [73] Assignee: Formex Ltd., Cite Jacques-Cartier,

Quebec, Canada [22] Filed: Aug. 15, 1969 [21] App1.No.: 850,493

All

Primary Examiner-Robert D. Baldwin Assistant Examiner-Dewalden W. Jones Attorney-Raymond A. Robic [57] ABSTRACT A plastic plug for use with a tie bar of concrete wall forms which is made of a plastic frustoconical body having an outer larger end intended to be applied against the inner surface of a form panel and having an inner smaller end that is embedded in the concrete of the wall. The plastic body is formed on the inside with a longitudinal through passage having a shape and size to slidably and snugly receive one end of a tie bar. The inner end of the body is closed but for the opening created by the passage so as to prevent entry of concrete inside the body. The outer end of the body has a circumferential sealing flange intended to be applied against the inner surface of a form panel to prevent entry of concrete inside the plug body.

In combination with this plug, a flat tie bar for holding concrete form panels in position and formed at one end with a pair of notches each provided along one of the two edges of the bar and opposite one another. A resilient ring pressed into the notches for abutment by the plug, said notches and ring being spaced from the end of the bar a distance such that the plug outer surface and the sealing flange may be slightly pressed, in use against the inner surface of a form panel.

2 Claims, 9 Drawing Figures 'PATENIEDFEB 22 m2 SHEET 1 BF 2 I NVENTOR Louis Philippe B I EAU I A TTORNE Y mamsnrfim 2 SHEET 2 OF 2 INVEN T OR Louis Philippe BROSSEAU ATTORNEY PLASTIC PLUGS FOR USE IN CONCRETE FORMS The present invention relates to plastic plugs for plugging face holes made by tie bars joining facing panels defining forms for use in making concrete walls or the like.

Face holes in concrete walls are presently plugged by wooden plugs which present many disadvantages particularly when flat tie bars are used in concrete forms such as of the type disclosed in my prior Canadian patents No. 588,509 of Dec. 8, 1959; 798,239 of Nov. 5, 1968 and US. Pat. No. 3,414,230 ofDec. 3, 1968.

There are indeed several difficulties inherent to the use of wooden plugs. Once they are put on the tie bars, they do not easily stay in their proper locations, that is in abutment against the inner surfaces of the form panels. Also, because the openings through which the tie bars extend are cylindrical and the tie bars are flat, concrete easily flows into the plug bores from both ends, particularly during vibration of the concrete. Thus, after setting, this concrete inside the plugs must be broken up with a chisel before the plugs can be removed. It can easily be seen that the use of such wooden plugs is expensive and none too satisfactory.

The present invention overcomes these difficulties by providing plugs made of plastic material and each having a frustoconical body formed with an inner guide means defining a longitudinal passage of a size and shape to allow the plug to be slidably and snugly displaceable on a tie bar. In this manner, the inner end of the body is closed but for the opening created by this passage and thus the entry of concrete inside the body is prevented.

Additionally and preferably, the plug has a circumferential sealing flange at the larger end of the body, this flange having a flat face intended to be applied against the inner surface of the concrete form to prevent entry of concrete inside the plug by that end.

In order to keep such plugs in proper position on the tie bars, they are preferably used with tie bars formed at each end with a pair of notches each along one of the two edges of the bar and opposite one another, a resilient ring being pressed into these notches for abutment by the smaller end of the plug. This particular feature will ensure that the plastic plugs of the invention will not untimely move along the tie bars when used. Also, the resilient rings are so positioned on the bars as to slightly press the plastic plugs against the inner surface of the form panel to ensure proper sealing of the larger ends of the plugs against the said inner surface.

A better understanding of the invention will be afforded by the following description having reference to the appended drawings wherein:

FIG. I is a perspective and cross-sectional view of a portion of a concrete form illustrating the use of the plastic plugs of the invention and the improved tie bar and resilient rings;

FIG. 2 is a side elevation view, one plug being shown in cross section, of the plug and bar combination according to the invention;

FIG. 3 is a cross-sectional view along line 3-3 of FIG. 1;

FIG. 4 is a perspective view of a plug-removing tool shown while being inserted inside a plastic plug according to the invention;

FIG. 5 is a side elevation and cross-sectional view of the tool and part of a concrete work, similar to the view of FIG. 4;

FIG. 6 is a cross-sectional view along line 6-6 of FIG. 5;

FIG. 7 is a perspective view, on a larger scale, of a concrete face hole with a decorative cap about to be inserted into the face hole;

FIG. 8 is a perspective view of a concrete work with face holes obtained by means of plastic plugs according to the invention;

FIG. 9 is a perspective view, on a larger scale, of the portion of FIG. 8 circumscribed by a rectangle made by broken lines.

The present invention is illustrated in FIG. I in use with concrete forms of the type illustrated and disclosed in my previous patents listed above. Such forms include a series of panels I fixed to boundary frame members 3 by means of rivets or the like, not shown. A boundary frame member 3 normally stands in abutment with a similar boundary frame of an adjacent panel and the two are held together by means of a series of lock plates 5 extending successively through the slots 5 7 and 9 of the boundary frame member 3 and tie bars 11, respectively, as well as through similar slots of the adjacent boundary frame member. The assemblies are locked into position by means of wedges (not shown) extending through slots 13 of the lock plates 5.

As clearly illustrated in FIGS. 1 and 2, the plugs I5 of the invention are slid over the tie bars 11 in the assembly of the forms prior to pouring of the concrete.

The plug 15 of the invention has a frustoconical body having an outer larger end 17 applied against the inner surface of the form panel 1 and an inner smaller end web 19 embedded in the concrete of wall 21. Plug 15 is made entirely of plastic material and is molded with inner guide means defining a longitudinal passage extending completely through the plug, this passage being of a shape and size to allow plug 15 to be slidably and snugly displaceable on tie bar 11. The inner end 19 of the body is closed but for the opening created by this passage thus preventing entry of concrete inside the body.

The plug body is formed with a tapered bore 25 and the aforementioned guide means are formed by ribs 27 extending diametrically opposite one another inwardly of bore 25 and formed along the inner edges thereof with guide ways providing the said passage 23 for engagement by the edges of the tie bar 1 l as clearly shown in FIG. 3.

The outer end 17 of the plug body has a flat face for abutment against the inner surface of the form panel I. As best illustrated in FIGS. 2 and 5, the plug body has a circumferential sealing flange 29 that has a flat face extending in the plane of the flat face of the outer end I7 whereby to seal the inside of the plug against entry of concrete at that end. The circumferential sealing flange 29 is preferably made sufficiently thin to be resilient.

The body of plug 15 is molded with a shoulder 3| along the outer surface thereof and immediately behind the sealing flange 29. By the provision of this shoulder 31, the plug I5 molds a recess 33 (FIG. 7) at the larger end of the face hole. Recess 33 will serve as a seat for a closing plastic cap 35 that, apart from serving to prevent entry of foreign matter in the fact hole, can be used to give a decorative effect by choosing an appropriate color therefor. Likewise, the circumferential sealing flange 29 will leave a recess 37 that will tend to increase the decorative aspect of the face hole as best illustrated in FIG. 9.

The plastic plug I5 of the invention is particularly intended for use on a flat bar 11 formed at one end with a pair of notches 39 (FIG. 2) each provided along one of the two edges of the bar 11 and opposite one another. A resilient ring 41, preferably made of rubber of circular cross section, has a diameter such as to be pressed into notches 39 and serves to retain plug 15 in position against the inner surface of panel I. Notches 39 and ring 41 are spaced from the end of rod 11 a distance such that the plug outer surface 17 and the plug sealing flange 29 may be slightly pressed, in use, against the inner surface of the form panel 1. Ring 41 will also prevent the plug 15 from sliding on the rod II, when the panels are assembled, away from the inner surface of panel 1.

Reference to FIG. 2 will show that the assembly is extremely simple, ring 41 being first put into position and plug 15 thereafter slid over flat bar 11. With a combination as described, it will be realized that the parts can be assembled most simply and there is no danger that the plugs 15 move out of position during the assembly of the other panels or during pouring and vibrating of the concrete.

Reference will now be made to FIGS. 4, 5 and 6 for the description of a tool for use in breaking and removing the end of a flat tie bar after the concrete 21 has set and the forms I, 3 have been removed. As will be seen from FIGS. 1 and 5, the ends of the bars 11 project out of the concrete work 21 after the forms have been removed.

The tool comprises a hollow stem 43 having an inner bore 45 defining a longitudinal inner chamber 47. One end of stem 43 has a transverse handle 49 fixed thereto while the other end has a removing head 51 fixed thereto as by welding. Head 51 has a central shoulder 53 and on one side thereof a tubular insert S5 integral therewith while a head member 57 extends on the other side of shoulder 53 and is also integral therewith.

The head member 57 is outwardly tapered to mate with the tapered bore 25 of the plug and is formed with a longitudinal slot 59 properly contoured to slide along the ribs 27, as shown in FIG. 6, and allow passage of the bar 11.

A hammering slug 61 is loosely mounted inside chamber 47.

The aforedescribed tool is used as follows:

The head member 57 of the removing head or mandel 51 is first inserted into the plug 15, the bar 11 extending through the passage defined by the slot 59 into the chamber 47 as illustrated in FIG. 5. The handle 49 is then rotated back and forth and oscillated to cause breaking of the bar 1 1. This will cause oscillation of the plug 15 because of the rectangular opening 18 (FlG. 3) through the transverse wall of the smaller end 19. The bar 1 1 will then break by the face of the concrete inside of the face hole and become riveted to the wall of the smaller end 19. The tool is then removed, bringing along with it the plug 15. The latter will usually be so tight over the removing head 57 that it cannot be removed by hand. Resort can then be had to the hammering slug 61 which can be made to hit the end of bar 1] inside chamber 47. Should these blows be insufficient, as it may sometimes happen, the plug 15 may be removed by means of a screw driver or the like acting on the sealing flange 27. For this purpose, a groove 63 (FIGS. 4 and S) is formed longitudinally of the shoulder 53 to allow the screwdriver to reach the sealing flange 29.

It will thus be realized that with the aforedeseribed plastic plug, many advantages are obtained as compared to the conventional wooden plug. In the first place, the plug can much more easily be put on and particularly stay on the rod 11. By the provision of the guiding passage 23, the plug will not tend to wabble and be displaced during the mounting of the forms 1, 3. The presence of rings 41 will further enhance the firm positioning of the plug and the more positive abutment of the sealing flange 29 against the inner face of the panel 1, thus providing a much greater safety against the inflow of concrete inside the plug. In other words, the plugs can be placed into position much more quickly, will not tend to move out of position during mounting of the forms and will provide greater sealing features particularly when the concrete is vibrated.

As to the tool for removing the plugs, it will be realized that the plug removing operation can be done extremely quickly and neatly.

I claim:

1. A plug molded from plastic material and intended for forming apparatus including a flat tie bar of generally rectangular cross section joining facing panels defining forms for use in making concrete walls or the like, wherein said plug comprises a hollow generally frustoconical body having an outer open end intended to be applied against the inner surface of a form panel and having an inner end to be embedded in the concrete of said wall, said inner end being closed by a straight web extending parallel with said outer open end, said body being further provided with guide means for said flat tie bar, the improvement therewith wherein:

a. said body has a flat annular outer face at said outer end extending into a thin annular flexible circumferential sealing flange, said face intended to seat squarely against the inner surface of a form panel whereby to seal the inside of said hollow body against entry of concrete therein;

b. said body is formed, exteriorly thereof and immediately behind said sealing flange, with a cylindrical shoulder intended to define, when said plug is removed from the said concrete, a recess for the insertion of a finishing closing cap, said body being further exteriorly frustoconical from said shoulder to the inner face thereof;

c. said body is interiorly frustoconical from said outer to said inner ends and said guiding means comprise ribs integrally formed with said body and extending the full length thereof between said ends radially inwardly and diametrically opposite one another, said ribs being further formed along the inner faces thereof with right an gular guiding grooves for the guiding of said flat tie bar. and

d. wherein said inner end straight web has a rectangular opening therethrough in alignment with said guiding grooves for the passage of said flat tie bar.

2. Apparatus as claimed in claim I in combination with a flat tie bar for holding concrete form panels in position and formed at one end with a pair of notches each provided along one of the two edges of said bar and opposite one another, and a resilient ring ofa size to be pressed into said pair of notches for abutment by said plug from said one end of said bar; said notches and ring being spaced from said end a distance such that said plug outer surface and said sealing flange may be slightly pressed, in use, against the inner surface of a form panel.

Claims

1. A plug molded from plastic material and intended for forming apparatus including a flat tie bar of generally rectangular cross section joining facing panels defining forms for use in making concrete walls or the like, wherein said plug comprises a hollow generally frustoconical body having an outer open end intended to be applied against the inner surface of a form panel and having an inner end to be embedded in the concrete of said wall, said inner end being closed by a straight web extending parallel with said outer open end, said body being further provided with guide means for said flat tie bar, the improvement therewith wherein: a. said body has a flat annular outer face at said outer end extending into a thin annular flexible circumferential sealing flange, said face intended to seat squarely against the inner surface of a form panel whereby to seal the inside of said hollow body against entry of concrete therein; b. said body is formed, exteriorly thereof and immediately behind said sealing flange, with a cylindrical shoulder intended to define, when said plug is removed from the said concrete, a recess for the insertion of a finishing closing cap, said body being further exteriorly frustoconical from said shoulder to the inner face thereof; c. said body is interiorly frustoconical from said outer to said inner ends and said guiding means comprise ribs integrally formed with said body and extending the full length thereof between said ends radially inwardly and diametrically opposite one another, said ribs being further formed along the inner faces thereof with right angular guiding grooves for the guiding of said flat tie bar, and d. wherein said inner end straight web has a rectangular opening therethrough in alignment with said guiding grooves for the passage of said flat tie bar.

2. Apparatus as claimed in claim 1 in combination with a flat tie bar for holding concrete form panels in position and formed at one end with a pair of notches each provided along one of the two edges of said bar and opposite one another, and a resilient ring of a size to be pressed into said pair of notches for abutment by said plug from said one end of said bar; said notches and ring being spaced from said end a distance such that said plug outer surface and said sealing flange may be slightly pressed, in use, against the inner surface of a form panel.