Pressure plate with integrated pressure indicator

Abstract

A pressure plate for securing at least one glass pane or panel against a frame includes a particular configuration of opposed wings adjoined by at least one resilient web, where raised portions of the opposed wings are moveable across a space towards each other thereby to bend the at least one resilient web out of a rest condition about a line of flexure an amount in proportion to the amount of force applied to the opposed wings.

Claims

1. A pressure plate to secure at least one glass pane or panel against a frame, comprising: opposed wings adjoined by at least one resilient web, each of the at least one resilient web extending between respective ends of the opposed wings and being resiliently bendable about a line of flexure, each of the at least one resilient web in a rest condition maintaining a space along the line of flexure between respective raised portions of the opposed wings that project forwardly beyond a front face of the at least one resilient web, each of the raised portions incorporating a respective bearing surface adjacent to the space and dimensioned to engage a respective portion of a head of a fastener passed through the space towards a frame; and at least one foot associated with each respective end of the opposed wings and extending beyond a rear face of the at least one resilient web, wherein the raised portions of the opposed wings are moveable across the space towards each other thereby to bend the at least one resilient web out of the rest condition about the line of flexure.

2. The pressure plate of claim 1, wherein an intermediate portion of each of the at least one resilient web is arched in the rest condition.

3. The pressure plate of claim 1, wherein the distance of the space is selected according to a desired compressive force of the at least one resilient web when the raised portions are in contact.

4. The pressure plate of claim 1, wherein the opposed wings and the at least one resilient web are formed from plastic.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In drawings which illustrate by way of example only a preferred embodiment of the invention,

(2) FIG. 1 is an elevation of a building faade showing prior art dutchies temporarily securing glass panes to window mullions.

(3) FIG. 2 is a plan view of a dutchy according to the invention.

(4) FIG. 3 is a front perspective view of the dutchy of FIG. 2.

(5) FIG. 4 is a rear perspective view of the dutchy of FIG. 2.

(6) FIG. 5 is an end elevation of the dutchy of FIG. 2 in a relaxed condition prior to being installed to a mullion.

(7) FIG. 6 is an end elevation of the dutchy of FIG. 2 in a compressed condition after being installed to a mullion.

DETAILED DESCRIPTION OF THE INVENTION

(8) FIG. 1 illustrates prior art aluminium dutchies 8 temporarily securing glass panes 2 to the window mullions 4 of a building faade in accordance with the current practice. Each dutchy 8 is cut from an aluminium extrusion, for example extra strips of the trim that will be used to finish the mullions, and screwed to the window mullions 4 through a hole drilled generally centrally along the length of the dutchy. A tape or gasket (not shown) is applied to the rear surface of the dutchy 8, i.e. the surface in contact with the glass panes 2, to protect the glass or panel.

(9) A dutchy 10 according to the invention, for fastening to a frame to secure at least one glass pane or panel against the frame, is illustrated in FIGS. 2 to 6.

(10) The dutchy 10 is formed from opposed wings 12, 14 adjoined by at least one flexible web 16. The dutchy 10 in the embodiment illustrated has two webs 16, one adjoining the wings 12, 14 at each end of the dutchy 10. In some embodiments the webs 16 are formed from plastic, for example polycarbonate which has the strength to flex without plastic deformation under the pressures required to effectively hold a glass pane or panel in position for the required amount of time, and the durability to withstand harsh weather conditions and a wide temperature range. In embodiments in which the wings are formed from plastic the entire dutchy may be formed from plastic, for example (without limitation) injection molded, due to the expedience and lower cost of forming the dutchy from a single material in a single step. However, it will be appreciated that since the only portion of the dutchy that needs to be flexible are the webs, rigid materials may be used for other components of the dutchy and the manufacturing techniques used may be adjusted accordingly.

(11) The webs 16 are disposed substantially within a plane containing a line of flexure L (shown in FIG. 2) along which each web 16 bends when the dutchy is compressed during mounting. The webs 16 extend between the wings 12, 14 and are adjoined (preferably formed integrally during the molding process) with each wing 12, 14 to hold the wings 12, 14 in a spaced apart position as described below.

(12) Each web 16 may be formed with a slightly curvate profile, so as to arch slightly forwardly as best seen in FIG. 5, which spaces an intermediate portion of the web 16 from the frame formed by the window mullions 4 (allowing room for the web 16 to flex toward the frame), and offers slightly greater compressive strength when the dutchy 10 is mounted. Each wing 12, 14 may optionally comprise one or more feet 20 for bearing against the glass pane or panel 2 when the dutchy 10 is mounted. In the embodiment shown the feet 20 project rearwardly beyond the rear faces of the webs 16, further spacing the webs 16 from the frame formed by the window mullions 4.

(13) Each wing 12, 14 further comprises at least one raised portion 22 projecting forwardly beyond the front faces of the webs 16. The raised portions 22, best seen in FIGS. 5 and 6, are disposed on either side of the line of flexure L and spaced apart by a predetermined distance when the dutchy 10 is in the rest or unloaded condition, as at 28 in FIG. 5.

(14) The opposed raised portions 22 of the wings 12, 14 are thus spaced apart along the line of flexure L. The raised portions 22 each provide a bearing surface 24 for engagement by at least one fastener 26, disposed at a position between the respective feet 20 of the opposed wings 12, 14, preferably generally centrally as shown. In the embodiment shown the bearing surfaces 24 bound the space 28 generally centrally along the length of the dutchy 10, as can be seen in FIG. 2.

(15) When a force is applied to the bearing surfaces 24, the webs 16 flex toward the frame formed by the mullions 4. Thus, in use, when the self-tapping metal screw 26 is disposed through the space 28 at the compression point represented by the bearing surfaces 24, as the screw 26 is set into the mullion 4 the head 26a of the screw contacts the bearing surfaces 24. Further rotation of the screw 26 to drive it into the mullion 4 causes the opposed raised portions 22 to move toward each other in proportion to the amount of the applied force. In the preferred embodiment the space 28 is designed to be a distance whereby when the raised portions 22 of the wings 12, 14 touch, the correct amount of compressive force is being applied to the dutchy 10 so as to securely hold the glass pane(s) 2 against the seat 4a of the window frame formed by the window mullions 4, as shown in FIG. 6.

(16) To remove the dutchy 10, the screw 26 is rotated in the reverse direction to detach the dutchy 10 from the mullion 4.

(17) Utilizing the dutchy 10 of the invention, if a glass pane or panel 2 under the influence of a wind load causes the dutchy 10 to deform, the deformation is elastic so the dutchy 10 will recover as soon as the wind load dissipates, and none of the fastening strength of the dutchy 10 is lost.

(18) A bight or annulus (not shown) may be provided through any convenient portion of the dutchy 10, or affixed to the dutchy 10 (for example by a web formed when molding the dutchy 10), to hold the screw 26. This facilities installation and removal by ensuring the screw is immediately available when the dutchy 10 is installed, and by providing a place to stow the screw when the dutchy 10 is demounted.

(19) It is also possible to embed electrodes (not shown) at a selected point along the upper ridges of each raised portion 22 along the space 28, serving as a switch in a circuit with a small battery (or other power source such as a photovoltaic cell) and an LED which will illuminate when the electrodes touch to indicate when the correct amount of force has been applied to the dutchy and installation is complete.

(20) Various embodiments of the present invention having been thus described in detail by way of example, it will be apparent to those skilled in the art that variations and modifications may be made without departing from the invention. The invention includes all such variations and modifications as fall within the scope of the appended claims.