CA1065684A - Spacer - Google Patents

Abstract

ABSTRACT

A spacer unit, a discharging gun and a method of retaining a spacing in an elastomeric seal between two surfaces is described. The system is particularly useful in the glazing trade for sealing large plate glass panes into aluminum frames. Previously the elastomer used was squeezed out under wind loads. Neoprene spacers used to prevent this displaced elastomer cause leaks. The spacer units of this invention overcome this problem. Each unit comprises a plurality of blocks skeletally inter-connected by webs. The blocks are resistant to a compressive force normal to the direction of linkage of the webs. The cross-sectional area of the blocks and webs presented to such a compressive force is small relative to the cross-sectional area lying within the outer periphery of the unit presented to such a compressive force.

Description

~65~84 This invention relates to a spacer unit, a method of maintaining a panel in a fixed relationship to a frame and a device for dispensing spacer units. The invention is part-icularly useful in the glazing trade, but should by no means be restricted to such applications arising in that trade.
The traditional method of fitting a panel into a frame, for instance a pane of glass in a window, is to pack putty between the glass and the part of the frame with which it would otherwise make contact, and on the edge of the outer face of the glass.
This method is not well adapted to fitting glass into metal frames. For these a back tape of butyl rubber or similar elasto~er is fitted into the frame cnd the glass is laid against this. The outer face of the glass is pressed toward the frame by suitable means with which thls invention is not concerned and is sealed by putty or a rubber extrusion.
In high-rise buildings, especially in places where the wind .
can be strong, it has been found that a back tape of such material as butyl rubber is extruded or squeezed out so that the glass becomes loose and rain can penetrate round its edgè. To prevent this it has become common practice to fit into the back tape at approximately 250 mm centres a series of blocks of a material such a neoprene which will not ready extrude. This is not wholly satisfactory since the neoprene block causes the elastomer in which it is embedded to bulge and to form gaps in such a way that rain can seep around the edge of the glass in the region of the neoprene block.
It is an object of the present invention to provide a method and apparatus which will avoid the aforementioned . : ~

' ' ' . ~ :

"; '"`` "' . '' ' '' ` ' ` ' '' ' '' ' ' ' , "'.~ '" ' .' `'' ~ . "`'' ' . ~ . ' 5~84 difficulties in a simple yet effective manner or which will at - least provide the public with a useful choice.
In one particular aspect the present inv,ention provides a spacer unit comprising a plurality oE incompressible blocks which are substantially symmetrical in all planes interconnected in - spaced relationship by webs in a substantially rigid skeleton, - said blocks and webs comprising an arrangement and material resis-tant to a compressive force normal to the direction of inter-connection of said webs and blocks; the cross sectional area of said blocks and webs being relatively small with respect to the entire cross sectional area lying within the outer periphery of said spacer unit, said webs and blocks defining openings there-- between for receiving sealant for preventing extrusion thereof ~ when the spacer unit is subjected to a compressive force normal to - , the direction of interconnection of said webs and blocks.

" '~ .

3 ~
~ -3-; - ' . ;
.

. . ~
.~.~ , .

1(165684 The invention may be more fully understood by having reference to the accompanying drawings wherein:
- ; Figure 1 is an exploded isometric view partly broken - ~ away of a device for discha:rging spacer units according to , :
--- the invention, ~ Figure 2 is a bottom plan view of the rear portion of , ~.
-- the casing of the device of Figure 1, -~ Figure 3 is the view III-III of Figure 1. 1 -Figure 4 is the view IV-IV shown in Figure 3.
.- 10 Figure 5 is a fragmentary isometric view of a window - installation incorporating the spacer unit and the method of ~ ~.
this invention. ~ _ .- Figure 6 is an elevation, partly in section, showing ¦
. . a fragmentary view of the device shown in Figure 1 discharging L
a spacer unit into elastomeric material in position on a window frame.
-- Figures 7a, 8a, 9a and lOa are plan views and figures 7b, 8b, 9b and lOb are side elevation of various embodiments - of spacer units according to -the invention.
:-' / I

~ ~' ' -,.- - /
~,; ' / .-'--.'-"`, / '_ . ~, .,,, ~
`. , .

.. , , - .. . . . . ...
- -:, , , ~ ~ , ... .. .. . .

~5684 .!
-- Figure lla and llb are respectively a p]an view and a side elevation of a strip of spacer units as illustrated in figure 7 adapted for use in the discharging device illustrated ! in figure 1.
Referring to figure 1, the device especially adapted to dispense spacer units according to the invention is illustrated.
Basically it comprises a casing consisting of moulded sections - 10 and 11 which are the mirror images of one another. The casing includes handle portions 16 and 17. The two halves of the casing are held together by a number of bolts 12.
- Within the casing running along the length thereof is a magazine chamber 46. As can be seen from figure 2 a slot 54 runs along 'he length of the magazine out of the bottom of the casing. A follower 50 comprises a cylin~rical portion having a protruding handle 51, the shaft of which protrudes through slot 54. A spring 52 is provided withln the enclosed cylindrical portion of follower 50. Spring 52 abuts against the casing wall at the end of the magazine chamber 46.
Spring 52 has sufficient rating to push the follower to the region of cylindrical boss 40. Chamber 46 has a transverse opening 48 in the bottom thereof intersecting slot 54 through which a strip of spacer units 70 may be inserted. It will be seen that during loading of the magazine, follower handle 51 and follower 50 may be twisted to one side or the other - in slot 55 to retain the follower at its stop position.
When the magazine has been loaded the follower is rotated so that handle Sl is aligned with slot 54 and the follower can advance along the magazine urging the strip of spacers 70 towards the front or discharge end of the magazine 46.
. . , .

: ' : ' . .

In the assembled dispensing dev ce there is provided a nose piece 32 having a front face and two side faces. There are two recesses 38 in the side faces which can be inserted over projection 39 from the front face 26 of the casing 10 and 11. Plunger 24 is designed to be enveloped by nose piece 32. It will be seen that plunger 24 interlocks with recess 22 in handle 14 whereby the plunger may be raised or lowered by the handle. There is provided a return spring 18 in socket 20 projecting downwardly from inside handle 14 to '~
raise the handle 14 and hence the plunger 24 to its rest position. As can be seen in figure 3 there are a pair of slots 34 in the sides of nose piece 32 into which orifice frame 36 can be slid. When the pieces are assembled and bolt 31 is screwed in through bore 30, slot 29 and bore 28 plunger 24 is in registry with the orifice in orifice frame 36.
Protruding downwardly from the bottom face of casing portions 10 and 11 is boss 40. There is provided an eccentric spacer 42 the central orifice of which fits over member 40.
A rest piece 44, the purpose of which will be described below, is provided abutting eccentric 42. Bolt 43 passes through these members into member 40 securing them in position.
It will be appreciated that the dispensing device can be conveniently moulded out of a suitable plastics material, for example acrylonitrile butadienestyrene. The two halves of the casing 10 and 11, and the handle 14 being moulded as separate components. Similarly, the exploded components shown in figure 1 may be moulded of a hard plastics material.
Because of its shearing function orifice frame 36 is prefer-ably constructed-of metal.
, 65~34 :,. .
In the embodiment illustrated handle 14 is pivoted on a pin in grip portions 16 and :L7. In an alternative embodiment pin 19 can be eliminated and a pair of protruding lugs provided at the heel of hand:Le 14. These lugs would embrace . . I
either side of grip portions 16 and 17 and rest within sockets on the outer surfaces of grip portions 16 and 17.
The principal of operat:ion of the device illustrated in figure 1 is virtually identical to that of a staple gun.
The compression of handle 14 against grip 16 forces the plunger 24 downwardly, forcing a spacer unit 70 out of orifice frame 36. On closer inspection of the nose piece, in figure 1 and in figure 4, it will be seen that there are - ~ provided square ori~ices 33. As will be described later in relation to figures lla and b a strip of spacer units 70 -` includes frangible webs 74. Follower 50 urges strips of spacer units 70 along magazine 46 whereby spacer units 70 ' abut against the inner face of nose piece 32 and the free ends of frangible webs 74 extend into orifices 33. The .
transverse inner edges 37 of orifice frame 36 are sharpened so that when plunger 24 pushes spacer units 70 down through the orifice, frangible web members 74 are sheared cleanly -off.
A method of glazing employing the spacer unit is illus-trated in figure 5. There is provided a typical extruded window frame 56 for use in glazing a high rise building.
The frame 56 comprises a vertical member 58 and a horizontal member 60, there being provided a rail receiving recess 61 in horizontal portion 60. One starts with a completely bare frame 56 and provides a strip of elastomeric material, for .

~ .
.: . ' . - . ,, ~.

..

example a butyl putty, along vertical member 58 near the edges thereof.
Referring now to figure 6, eccentric 42 is adjusted so that the vertical position of the gun is at the correct height to discharge a spacer 70 into elastomeric material 62. The horizontal distance of the discharge point to the elastomer is adjusted by varying the position of rest piece 44 so that the spacing between the rest piece and the dis-charge orifice is slightly greater than the thickness of the vertical member 58 and the elastomeric material 62.
The spacers 70 are conveniently discharged at 250 mm centres along the length of frame 58. Next there are pos-itioned blocks 6~, conveniently of neoprene rubber resting at the apex of vertical portion 58 and horizontal portions 60. A pane of glass 63 is rested on blocks 64 and pressed .
against the elastomer 62 into which spacer units 70 have ~ -:
been injected. The elastomeric material 62 is flattened against the pane of glass to effect a complete seal therealong.
Spacer units 70 are chosen so as to be slightly less in . .1 thickness than the thickness of the elastomeric seal. Thus .,.
the pane of glass 63 will extrude sufficient elastomeric material 62 to provide a complete seal but the spacers 70 . :
will provide an effective stop to prevent elastomeric material being e~truded completely out of the seal when the pane of glass is subjected to compressive forces in the direction of the frame, for example by wind loading. ~ .
The final step in the glazing operation comprises :
inserting a further elastomeric sealant material 68 on the ~.
opposite side of the glass, inserting suitable spacers into ~

, .

- . . . .: : . ~ . .. : .

,- ., - . . ..

. - . .

10656~34 the-sealant material ancl sliding a s~itable retaining memher .
66 into recess ~1 to hold the glass in a firm seal.
Spacer units according to the present invention are illustrated in enlarged views in figures 7 to 11. The most preferred embodiment is that shown in figures 7 and 11.
This embodiment is preferred because the cylindrical shape of the blocks is the most readily moulded. The units comprise two parallel rows each consisting of five cylindrical blocks 71. Each block in a row is connected to its neighbour by a web 72. There are provided three cross webs on the first third and fifth blocks in a row. Exemplary dimensions are illustrated in figures 7a and 7b. The spacing to be achieved by the unit 70 shown therein is the dimension 2, the length of the longitudinal axis of each of the cylindrical blocks, which is 4 mm. The diameter of each cylinder as illustrated is the dimension 3 which is 1.5 mm. The dimension 8 which is ~he spacing between centres of adjacent blocks is 4 mm. A thickness of each web 72 is a dimension 5, thereupon 0.5 mm while the width of each web 72 is the dimension 7, 1.5 mm. It will be appreciated that the side elevation view in 7b is on a different scale from that shown in figure 7a.
In figures 8a and 8b there is illustrated a spacer unit 76 comprising spherical blocks 77 interconnected by webs 78 which are the same as webs 72 in figure 7. In figure 9 there are illustrated spool shaped blocks 80 interconnected by web units 81 to form a spacer unit 79. Blocks 83 in figure 10 comprise substantially rectangular walls which have been cut away to include web portions 84 making up a spacer unit 82.

_ g _ . ., , ; ., .- : ,:

.
:

- :

In figure 11 there is illustrated a strip comprising 6 spacer units 70. ~ach of these spacer units is interlinked by a pair of franqible webs 74 joining outer blocks 71. As was described hereinabove, these frangible webs 74 are preferably sheared off in a discharge gun.
Althou~h spacer units 70 are preferably applied through use of the device illustrated in figures 1 to 4 and 6 indiv-idual spacer units 70 could be applied by hand in more modest applications of the invention. The width of the f various web members (dimension 7 in figure 7b) is less than the longitudinal length of the blocks (dimension 2 figure 7b). This design is preferred as the entire spacer unit 70 will be embedded in elastomer except for the end faces of blocks 71. If the dimensions 2 and 7 were identical the whole of the frame periphery of the spacer unit 70 at either end thereof would be in contact with the glass of the frame.
Elastomer would be within the enclosed empty space. Any -minor void or wrinkle in the elastomer or any scratch in the - frame would allow the water to reach the peripheral face.
Since the face would be continuous the water would track around the spacer and would increase the probability of leakage to the inside surface of the glass. When the contin-~ uity of the peripheral edge is broken as illustrated the spacing between the faces 71 are filled with putty thus reducing the chances of occurrence of leakage of this type:
One advantage of the preferred embodiment of the frame is that under loading it is possible to have some distortion - of the geometry of the unit as a whole without loss of its spacing function. The smaller dimensions of the webs allow : ' , ` . . - 10 -- - . . , - . . . .

ti5684 a certain amount of flexibility so that the distortion occurs in the webs.
Spacer units are cheapest if they can be moulded, pressed or cast. The material should be non-extrudable under design (e.g. wind) loads. It should not damage glass.
It should be inert to glazing compounds and to weather. It should have a life compatible with that of the glazing system.
It has been found that an acetal resin, for example that sold under the trade mark "Delrin", satisfies these requirements. In the form described in relation to figures 1 and 2 the variation of its length dimension under a wind gust imposing a load of 50 kg on one spacer is 0.5~ to 1~
and it recovers from creep after this load has been applied and removed. Such a spacer unit is intended for continuous loads of 10 -15 kg.
It may be noted that a 2 metre square of glass subjected to a 150 kph. gust of wind imposes a shortterm load of 5 kg on each spacer, if the centre to centre distance of the spacers is 250 mm approximately.
It has also been found that a glass or mineral filled thermoplastics material or else acrylonitrile butadlene styrene (ABS) is suitable. The invention does not lie in the selection of any particular plastic, however.
When spacers of the type here described and inserted with a spacing as here suggested are used in conjunction with a butyl rubber back tape, it is found that the whole spacer is embedded in butyl rubber, except for the end faces of blocks 1, and that there is no significant bulge in the butyl rubber over the site of the spacer.

:

- - . , . . ....... :. . . -- : . : , ~, - , .': .

-`` 10656&19L
- The spacers of the present invention call be used with putty as readily as with butyl back tape.
Such spacers can be used Eor a wide variety of purposes, for some of which the size would best be markedly different from the size here suggested. When such spacers are to be used in such circumstances that they are to be buried in an elastomer the relation between total area of plastic in the plane shown in figure 1 with the total area of the array shown in figure 1 must be considered. The relation here described is suitable for a spacer of the size described, when used with butyl rubber. In particular when the size of the spacer is much greater than here described, it may be possible to i-c ease the elative ~moune of resln.

.~ .

~ ` ' ' :, .
.. . .
.
.. ~ , . . ~, ; 1 , . . .. . ..

.
-' , , ' ' ' ' ,' ~: '', , ' ~ ' , , ~
-. . .. . . . .

Claims (11)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A spacer unit comprising a plurality of incompressible blocks which are substantially symmetrical in all planes inter-connected in spaced relationship by webs in a substantially rigid skeleton, said blocks and webs comprising an arrangement and mater-ial resistant to a compressive force normal to the direction of interconnection of said webs and blocks; the cross sectional area of said blocks and webs being relatively small with respect to the entire cross sectional area lying within the outer periphery of said spacer unit, said webs and blocks defining openings there-between for receiving sealant for preventing extrusion thereof when the spacer unit is subjected to a compressive force normal to the direction of interconnection of said webs and blocks.

2. The spacer unit as claimed in Claim 1 wherein each said block is cylindrical, right prismatic or spool shaped.

3. The spacer according to Claim 2 wherein said blocks have parallel longitudinal axes perpendicular to the direction of link-age of each of said webs, one set of end faces lying in a first plane and a second set of end faces lying in a second plane, said first and second planes being parallel.

4. The spacer according to any one of Claims 1 to 3 wherein the cross sectional area within the periphery of said spacer unit is rectangular.

5. The spacer unit of any one of Claims 1 to 3 wherein said webs are elongate, the longitudinal axes of said elongate webs are normal to the longitudinal axes of each of said blocks and the width of each said elongate web is less than the longitudinal length of said blocks.

6. The spacer according to claim 3 wherein each said spacer unit comprises two parallel rows of five blocks each, there being provided webs interconnecting the first third and fifth blocks of the successive rows.

7. The spacer units according to claim 6 interconnected by pairs of frangible interconnecting webs.

8. A spacer unit according to claim 7 wherein said blocks are spherical.

9. Spacer units according to claim 3 constructed of an acetal resin derived from the polymerization of formalde-hyde.

10. The spacer unit according to claim 3 constructed of acrylonitrile butyl styrene.

11. The spacer unit according to claim 3 constructed of glass or a mineral filled thermoplastic.