US 3234699 A
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Description (OCR text may contain errors)
Feb. 15, 1966 c.1-1. SMITH 3,234,699
BUILDING BLOCK ASSEMBLY CONSTRUCTION AND METHOD OF ERECTION Filed April 25, 1961 2 Sheets-Sheet 1 INVENIOR W fiaz lelalaflimitlp BY W1 M AGENT Feb. 15, 1966 c. H. SMITH 3,234,699
BUILDING BLOCK ASSEMBLY CONSTRUCTION AND METHOD" OF ERECTION Filed April 25, 1961 .2 SheetsSheet 2 INVENTOR W flarlelanfl J'm'tlp AGENT United States Patent 3,234,699 BUILDING BLOCK ASSEMBLY CONSTRUCTION AND METHOD OF ERECTION Carleton H. Smith, Islington, Ontario, Canada, assignor to National Lead Company, New York, N.Y., a corporation of New Jersey Filed Apr. 25, 1961, Ser. No. 105,388 8 Claims. (Cl. 52-173) The present invention relates to a new and novel building block assembly construction and method of erection thereof, and is particularly concerned with the erection of walls and like assemblies formed of glass blocks.
While the present invention may be applicable for many different types of building blocks, it is of particular utility in connection with glass blocks which permit a large amount of light to filter therethrough and which may either be clear or colored as desired.
In the prior art, glass block assemblies are ordinarily set up utilizing mortar which may or may not be reinforced for maintaining the glass blocks in operative position with respect to one another. The present invention is particularly directed to the elimination of the utilization of mortar between the blocks and a novel support means is provided, this support means being constructed of a relatively rigid yet deformable material. While the support means may be constructed of various substances such as metal or plastic which have the desired characteristics, lead is a particularly advantageous material for this purpose.
Prior art assemblies employing mortar and the like suffer from a number of disadvantages which are overcome with the arrangement of the present invention. A particular problem occurring when glass block panels are set up with mortar is the fact that the completed panel is of a rigid and inflexible construction. Accordingly, when the glass blocks are subjected to expansion and contraction as caused by heating and cooling or when sudden presure changes occur due to wind or even more particularly when settling of the building occurs, the panel is often cracked since there is not a suflicient degree of elasticity or give to the panel which will permit the necessary degree of deformation. Furthermore, when such panels are struck by external objects, they are easily fractured.
Glass block walls employing mortar or similar binder material also must be laid such that the blocks are aligned with one another to preserve the continuity of the longitudinal and vertical mortar seams between the blocks in order to obtain the necessary degree of strength for the wall.
When laying the blocks the seams must be repointed by by the mason, and it is often necessary to provide external supports in order to ensure the necessary structural strength to the finished wall.
The speed of laying the blocks may be limited since only a certain amount of weight can be placed on each mortar joint while it is still soft. Accordingly, it may be necessary to await hardening of the mortar before proceeding with the laying of more blocks.
A further limitation of mortar type joints is the fact that it is necessary for the mason to have access to opposite sides of the wall when laying the blocks thereby necessitating the utilization of hazardous and costly scaffolding at the outside of the wall. In addition, it is diflicult if not impossible to successfully erect a glass block wall when employing mortar joints during freezing weather due to the nature of the mortar itself. It is further quite diflicult to replace individual blocks in a finished glass block assembly employing mortar joints.
In the present invention, a novel support means is employed between the adjacent building blocks. This sup- "ice port means comprises a'plurality of deformable elongated support members which in the case of glass blocks are adapted to cooperate with the peripherally extending lips formed along lateral edges of each block adjacent to the opposite faces of the blocks. The support members include main body portions having flanges formed at opposite ends thereof which define oppositely facing channel portions for receiving the lip portions of the blocks. v The construction of the support members issuch that the flange portions disposed adjacent the inwardly facing surfaces on the lip portions of the blocks may be more readily deformed than the flanges along the opposite edges of the support members thereby causing any necessary deformation of the support members to occur primarily at that portion of the support member which is hidden from view thus ensuring a neat and attractive finished appearance to the assembly at all times.
The main body portion of the support members is provided with a plurality of longitudinally extending ridges which project from opposite sides thereof, these ridges serving as a means which is readily deformable and permits the desired degree of relative movement between the building blocks.
A sealing means is also provided between the support members and building blocks thereby ensuring that a good seal will be maintained therebetween at all times.
The deformable nature of the support means ensures that settling of the assembly, expansion or contraction of the individual blocks and further sudden pressure changes or impact with foreign objects will not cause breakage or cracking of the assembly since in effect, the arrangement provides a floating block arrangement thereby permitting the blocks to move relative to one another to accommodate for such conditions.
The over-all arrangement provides a better thermal barrier than assemblies employing mortar type joints since in the present invention the space between the blocks is filled with air rather than mortar, the air serving as a better heat insulation.
In addition, with the arrangement of the present invention, conventional expansion joints are not necessary thereby eliminating this possible source of thermal radiation.
The support means of the present invention also provides better acoustical insulation, better dust-free protection, and is also better vibration-proof than assemblies employing mortar-type joints.
The utilization of the support means of the present invention also permits a greater variety of arrangements since the individual blocks may be disposed in staggered relationship to one another since it is not necessary to maintain continuity of horizontal and vertical seams as is necessary with mortar joints. When lead is employed as the material of the support members, the appearance is further enhanced since the lead oxidizes to a pleasant slate gray color. The support means of the present invention requires less maintenance than a mortar-type joint, and furthermore, more light can pass through'the glass blocks since the space between the blocks is not filled with a solid substance as occurs when mortar is employed.
A wall of glass blocks may be laid more quickly and 'with less skill when employed with the present arrangement, wherein pre-cut and pre-cemented support means may be employed. The support means of the present invention may comprise extruded lengths which may be cut to any desired length at the job site. No repointing of seams is necessary when laying a wall, and there are no limitations on loading of the material forming the joints between the various blocks.
When utilizing the support means of the present invention, a further advantage accrues due to the fact that the entire assembly may be set up from one side thereof, and
in this manner the necessity of providing scaffold means and the like in order to gain access to both sides of the assembly is eliminated.
The assembly of the present invention can be erected even in freezing weather, and the ambient temperature does not limit its application. The individual blocks may be more readily removed since the adjacent blocks may be eased away from any individual block and a new block can be inserted in position. The deformable support means can then be beaten back into place on the side from which the old block was removed in order to retain the new block in place.
An object of the present invention is to provide a new and novel building block assembly which accommodates settling of the assembly as well as expansion and contraction of the individual blocks, and which resists breakage when struck by external objects and can withstand sudden pressure changes.
Another object is the pnovision of a building block assembly which provides a better thermal barrier than mortar type joints, and further which provides good acoustical insulation, dust-(free protection and which is relatively vibration-proof.
A further object of the invention is to provide a building block assembly which permits the employment of a. staggered block arrangeemnt which will increase the stability of the structure.
A still further object of the invention is to provide a novel method of erection of a building block assembly which is cheaper than prior art methods and which requires less time and less skill on the part of personnel erecting the assembly.
Yet another object of the invention is to provide a novel method of erecting a building block assembly wherein the blocks may be installed from only one side of the assembly.
A yet further object of the invention is the provision of a novel method of erecting a building block assembly wherein the method can be carriedout even under freezing weather conditions and which permits ready replacement of individual blocks.
Other objects and many attendant advantages of the invention will become more apparent when considered in connection with the specification and accompanying drawings, wherein:
FIG. 1 is an elevational view of a typical building block assembly according to the present invention;
FIG. 2 is a view similar to FIG. 1 illustrating a sta gered block arrangement;
FIG. 3 is a longitudinal section through a portion of a building block assembly as shown in FIG. 1, illustrating the manner of intercooperation of the blocks and support means therefor;
FIG. 4 is a perspective sectional broken-away view of a support means according to the present invention;
FIG. 5 is an enlarged view of one of the joints between the lip portions of two adjacent blocks as shown in FIG. 3; and
FIG. 6 is a perspective sectional broken-away view of a modified form of support means.
Referring now to the drawings wherein like reference characters designate corresponding parts throughout the several views, there is shown in FIG. 1 a building block assembly indicated generally by reference numeral 10 .which in the present instance is shown as forming part of a wall '11, although it is apparent that the building block assembly may form the complete wall if desired.
The assembly as shown includes a plurality of glass blocks 12 which are disposed in edge-to-edge relationship with one another, that is to say, that the edges of each block are adjacent but spaced from the edges of the adjacent blocks. As shown in this figure, the blocks are vertically and horizontally aligned with one another as is usually the case in glass block assemblies. The assembly including the nine blocks numbered '12 in FIG. 1 is mounted upon a sil-l 15, and is surrounded by a framework including members 16, '17 and 18.
The individual blocks are suported in operative relationship as shown by a plurality of unique suport members. Four continuous support members 20, 21, 22 and 23 extend longitudinally of the assembly and serve to support the upper blocks on the underlying blocks as will be more fully hereinafter discussed.
A first plurality of vertically extending support members 25 extend between the horizontal support members 20 and 21, it being evident that support members 25are considerably shorter than the horizontally extending support members and that members 25 are interposed between the vertically oriented edges of the blocks 12. In a like manner, a second plurality of vertically extending members 26 are disposed between horizontally extending support members 21 and 22, and a third plurality of vertically extending support members 27 extend between horizontally disposed support members 22 and 23. The horizontally extending support members 2023 are shown as being continuous so as to provide greater strength to the overall assembly.
Referring now to FIG. 2, an arrangement is illustrated wherein a plurality of glass blocks 30 are disposed in staggered relationship to one another. This is feasible in the present invention due to the fact that there is no necessity for maintaining a continuity of vertical or longitudinal joints as is the case with mortar-type seams.
Here again, a sill 31 and surrounding support members 32, 33 and 34 serve to maintain the block assembly in position within a wall 35. A plurality of continuous longitudinally extending support members 40, 41, 42 and 43 are provided. A first plurality of vertical extending support members 45 are provided between longitudinal support members 40 and 41, a second plurality of vertical support members 46 are provided between longitudinal support members 41 and 42, and a third plurality of vertical support members 47 are provided between longitudinal support members 42 and 43. The staggered block arrangement shown in FIG. 2 is desirable since it provides a varied appearance as compared with conventional glass block panels and it is further evident that the glass block panel may be even further modified if desired.
Referring now to FIG. 4 of the drawings, a typical support member is indicated generally by reference numeral 50, this support member being preferably formed by extrusion, and the support member may be provided in any desired length. A length of support member may be easily cut at the job site in the case where the support member is formed of lead, and for that matter various other materials such as plastic or the like may be readily cut to the desired length. In any event, the support member will be formed of a relatively rigid material which is adapted to -provide structural strength, and yet it will be formed of a material which can deform slightly under oad.
Support member 50 includes a central main body portion 51 which is elongated and is provided with a first plurality of longitudinally extending ridges 52 projecting from one side thereof and a second plurality of longitudinally extending ridges 53 projecting from the opposite side thereof.
It will be understood that these ridges 52 and 53 extend continuously throughout the length of the support member.
It will be noted that the outermost surfaces of the ridges are rounded as indicated at 52 and 53' and these outer rounded portions facilitate deformation of the ridges when under load to permit shifting of the associated blocks with respect to the support member. It is to be appreciated however that the outermost surfaces of the ridges may have other configuration without departing from the scope of this invention.
A pair of opposite laterally extending flanges and 61 are formed along the outer longitudinal edge of the support member, the outer surface 62 being that which is normally presented to view in the finished assembly. It will be noted that the inner surfaces 64 and 65 of flanges 60 and 61 respectively are more or less arcuate in configuration.
Formed longitudinally along the inner edge of the support member are a pair of flanges or leg portions 67 and 68 which are disposed angularly with respect to one another and as herein shown define an included angle A of less than 180. It should be recognized however that inclusion of such angular construction is a matter of choice and largely serves to eliminate some material of construction thereby resulting in a lighter element. If desired the flanges 67 and 68 may conform substantially to the construction shown for flanges 60 and 61, these being joined by outer surface 62.
Sealing means is provided on the support member and as seen in FIG. 4, the sealing means comprises a first layer 70 of sealing material disposed on the under side of the support member and a second layer 71 of sealing material disposed on the upper side of the support member. It will be noted that the layers 70 and 71 have inner surfaces which conform to the upper and lower faces of the support member 51), and that the layers are relatively thin and substantially cover the longitudinally extending upper and lower faces of the support member. The sealing layers extend throughout the longitudinal length of the support member, and are preferably bonded thereto before shipping to the job site. As will be apparent the sealing means may be preformed without the conforming surface but then should be of such charateristics so as to freely assume the indicated shape when some pressure is applied.
With this arrangement, the support member and sealing material are provided as an integral unit, and the blocks may be laid directly on the support or other means for completing the assembly.
The sealing material of layers 70 and 71 may be for example Thiokol, LP base sealant.
It will be understood from an inspection of FIG. 4 that flanges 6t) and 67 cooperate with the main body portion 51 of the support member to define an upwardly facing channel portion, while flanges 61, 68 cooperate with the main body portion 51 to define a downwardly facing channel portion.
These channel portions are adapted to receive lips formed on building blocks as will hereinafter appear.
Referring now to FIG. 3, a section is typically shown through a completed assembly, and as seen in this figure, a sill is indicated by reference numeral 75. A base or supporting member 76 which may be formed of lead or similar material is provided and is supported in place on the sill and fixed thereon by a layer of mortar 77 or the like.
Extending along opposite longitudinal edges of member 76 are assemblies 80 and 81, each of these assemblies forming substantially the upper half of the support member shown in FIG. 4 as will be evident from an inspection of the structures thereof.
Sealing means 82 and 83 is provided on the upper surface of each of assemblies 80 and 81 in the manner described above.
The glass blocks of this panel assembly are indicated generally by reference numerals 85, two complete blocks being shown in vertical section and the lower portion of the third block being illustrated. These glass blocks are of typical construction, the blocks including side walls 86 and 87 having outer faces 88 and 89 respectively. Upper and lower walls 90 and 91 respectively are provided, these upper and lower walls extending between the side walls as will be clearly understood.
A plurality of ridges 95 are normally formed along the lateral faces of the glass blocks, these ridges serving in a conventional mortar-type joint to provide a better 6 bond with the joint. These ridges have no particular utility in the present invention, however.
Each of the blocks has a first lip 100 which extends peripherally completely around one lateral edge of the block adjacent face thereof. A second similar lip 101 extends peripherally around the lateral edge of the block adjacent to the opposite face 89 thereof. It will be noted that lip includes an outwardly facing arcuate surface 105 and an inwardly facing sloping surface 196 which each of the lips 101 includes an outwardly facing arcuate surface 107 and an inwardly facing sloping surface 108.
As seen in FIG. 3, support members 50 identical with the support member 50 shown in FIG. 4 are provided, these support members extending longitudinally between the lips of adjacent blocks. It will be understood that similar support members 50 will be disposed between the vertically extending lip portions of each of the blocks.
In laying or erecting the assembly, the base member 76 is first fixed in position, and the lower glass block is supported thereon with the lip portions 101 and 101 seated within the upwardly facing channel portions of assemblies 80 and 81 at opposite edges of support member 76. Support members 50 are then disposed along the upper lip portions 100, 101 of the lowermost block, the support members, of course, being reversed in position with respect to one another. At this point, the lip portions along the upper edge of the block are received in the downwardly facing channel portions of the support members 50. Then a second glass block is placed within the support members 50 such that the lips formed along the lower portion thereof are seated within the upwardly facing channel portions of support members 50.
It is evident that this procedure can be repeated in laying additional courses of block and, of course, the vertical support members are interposed between the vertically extending lips of the blocks as the courses are extended in a horizontal direction.
Referring now to FIG. 5, the coaction between a typical support member 51' and the lips 100' and 101' of typical glass blocks 85' is illustrated. The lower edge 110 of lip 100 rests upon the upper edges of ridges 111 projecting from one side of support member 51'. The upper surface 113 of lip portion 101' engages the outer surfaces of ridges 105 projecting from the opposite side of support mem ber 51'.
As the glass blocks tend to shift with respect to one another for one reason or the other, the support member 51' is adapted to deform accordingly, and as seen in FIG. 5, the outer portions of the ridges 111 and 115 have been flattened out from their original arcuate configura tion to permit such relative movement.
At the same time, the sealant layers and 121 disposed between opposite sides of the support member and the lips of the blocks has flowed between the support member and blocks, and will be squeezed out between the spaces defined between the flanges of the support member and the inwardly and outwardly facing surfaces of the lips on the blocks.
It is evident that if additional deformation is required of the support member, the ridges 111 and 115 may be considerably deformed to permit such movement, and in addition, as pointed out previously, the flange portions 67' and 68' of support member 51' may be relatively easily deformed to permit lateral shifting between the block members as opposed to the vertical or horizontal shifting permitted by the ridges 111 and 115.
In addition to permitting the desired degree of shifting of the blocks, the ridges formed on opposite sides of the support member serve to provide a better bond between the support member and the associated layers of sealant material.
Referring now to FIG. 6, a modified form of the invention is illustrated wherein the support member indicated generally by reference numeral is of identical construction with support member 50' described in FIG. 4.
7 In this modification, the layers of sealant material 131 and 132 are disposed in the bottom part of the oppositely facing channel portions defined by the support member, and fiat surfaces 133 and 134 are defined by the outermost portion of these layers.
Disposed in overlying relationship to the flat surfaces 133 and 134 are layers of a protective material 135 and 136 respectively. These layers may be formed of a suitable material such as paper or the like which normally protects the underlying layers of sealing material until the support member is to be mounted in operative position.
The protective layers 135 and 136 are preferably attached to the associated surfaces 133 and 134 by an adhesive material so that they will be retained in operative position and yet can be peeled off of the sealing layers when it is desired to lay blocks with the support member. As shown in FIG. 6, the layer .135 has been partially peeled away from the sealing layer 131. 7
It is apparent from the foregoing that there is provided a new and novel building block assembly which accommodates settling of the assembly as well as the expansion and contraction of the individual blocks, and which resists breakage by external objects and can withstand sudden pressure changes.
This is accomplished due to the construction of the integral support means which is provided with deformable portions permit-ting relative movement of the blocks. The material of the support member is such that it provides a better thermal barrier than mortar type joints, and furthermore, lead in particular provides good acoustical insulation. The joint will additionally be absolutely dust-free since the sealing means prevents any dust from seeping through the joint.
A staggered joint assembly can be readily constructed with the arrangement of the present invention, and maintenance in the case of lead support members is nil.
More light is also enabled to filter through the overall assembly since the joints between the blocks are not completely filled with mortar or other means, but rather the blocks are supported only along the lip portions thereof. The method of erection is cheaper than prior art methods since it requires less time and less skilled personnel to perform the operation. It is evident that even the most unskilled laborer can easily erect the assembly since all that need be done is to lay the members in abutting relationship with one another as described.
The novel method of the present invention also permits the erection of a building block assembly from only one side thereof since the support members can easily be mounted on the lips from one side of the assembly whereupon the blocks may also be laid into place from the same side of the assembly.
The building block assembly can be erected even under freezing weather conditions since freezing weather will not affect the support means or the building blocks.
The individual blocks can also be readily replaced by deforming the support members and easing the adjacent blocks away from the block which it is desired to move. A new block can then be inserted in place of the old one and the surrounding blocks eased back into position and the deformable support members beaten back into the desired operative position.
While the instant invention has been described in terms of construction of glass block assemblies, it is intended that it also embody other block assemblies, including but not restricted to plastic, metal, refractories and the like.
As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, and since the scope of the invention is defined by the appended claims, all changes that fall within the metes and bounds of the claims or that form their functional as well as conjointly cooperative equivalents are therefore intended to be embraced by those claims.
1. A building block assembly comprising a plurality of blocks being in edge-to-edge relationship with one another, each of said blocks having spaced lip portions formed along lateral edges thereof adjacent to the opposite faces of each block, and support means disposed between only one lip portion of adjacent blocks andengaging only said one lip portion thereof, said support means being formed of a relatively rigid yet deformable material, each of said support means having flange means formed thereon adjacent only one lip portion of lock block for locking the support means in position, the space between the adjacent assembled blocks intermediate the lip portions thereof and between support means bounding such space being free and unobstructed, and sealing means disposed between said support means and the lipportions of said blocks.
2. A building block assembly comprising a plurality of blocks, adjacent ones of said blocks being in edge-toedge relationship with one another, each of said blocks having spaced peripherally extending lip portions along lateral edges thereof adjacent to the opposite faces of each block, each of said lip portions including an outwardly facing surface and an inwardly facing surface,
" and support means disposed only between adjacent single lip portions of each pair of adjacent blocks, said support means being formed of a relatively rigid material which is deformable under load, said support means having flange means formed along opposite edges thereof adjacent only one lip portion of each block for locking the support means and blocks in operative position, the space between the adjacent assembled blocks intermediate the lip portions thereof and between said support means being free and unobstructed and sealing means disposed between said support means and said blocks, one of the flange means of each of said support means being disposed adjacent to the outwardly facing surfaces of the adjacent lip portions while the other flange means of each of said support means is disposed adjacent the inner surfaces of the adjacent lip portions.
3. A building block assembly comprising .a plurality of blocks, adjacent ones of said blocks being in edge-toedge relationship with one another, each of said blocks having spaced peripherally extending lip portions along lateral edges thereof adjacent to the opposite faces of each block, each of said lip portions including an outwardly facing surface and an inwardly facing surface, and support means disposed between adjacent lip portions of each pair of adjacent blocks, said support means being formed of a relatively rigid material which is deformable under load, each of said support means being elongated and including a main body portion having laterally extending flange means at opposite ends thereof adjacent only one lip portion of any one particular block, one of the flange means of each of said support means being disposed adjacent to the outwardly facing surfaces of the adjacent lip portions while the other flange means of each of said support means is disposed adjacent the inner surfaces of the adjacent lip portions, said main body portion having longitudinally extending ridges projecting outwardly from opposite sides thereof and at substantially right angles thereto, said ridges extending continuously throughout the length of said main body portion and having a cross-sectional configuration which tapers outwardly away from the main body portion to a smaller dimension, said ridges being readily deformable to permit relative movement of the associated adjacent blocks, and sealing material disposed between said support means and said blocks.
4. Apparatus as defined in claim 3, wherein said other flange means comprises a pair of leg portions disposed angularly with respect to one another to include an angle of less than 5. A building block assembly comprising a plurality of glass blocks, adjacent ones of said blocks being in edge-to-edge relationship with one another, each of said blocks having spaced peripherally extending lip portions along lateral edges thereof adjacent to the opposite faces of each block, each of said lip portions including an outwardly facing surface and an inwardly facing surface, and support means disposed between adjacent lip portions of each pair of adjacent blocks, each of said support means being elongated, and being formed of a deformable material, said support means each including an elongated main body portion having a plurality of longitudinally extending ridges projecting from opposite sides thereof and extending substantially normally therefrom and continuously throughout the length of the support means, said ridges having a cross-sectional dimension tapering outwardly away from the main body portion of the support means to a smaller dimension and having rounded outer end portions, said main body portion having first flanges projecting laterally therefrom in opposite direction along one edge thereof and being disposed adjacent the outer faces of the associated lip portions, said main body portion having second flange means projecting therefrom along the opposite edge portion thereof, said second flange means comprising a pair of leg portions disposed angularly with respect to one another to define an included angle of less than 180, and sealing means disposed between said support means and the associated lip portions, said sealing means comprising a first layer of sealing material disposed on the underside of the support means and a second layer of sealing material disposed on the upper side of the support means, each of said support means being disposed with said second flange means adjacent the inwardly facing surface of the associated lip portion, and each support means being disposed adjacent only one lip portion of a particular block with the support means associated with the adjacent lateral edges at the opposite faces of a particular block being spaced from one another, and with the space therebetween being substantially free and unobstructed.
6. Support means for use in a building block assembly comprising an elongated member formed of relatively rigid yet deformable metallic material, said member ineluding an elongated flattened main body portion, said main body portion having integral longitudinally extending continuous ridges projecting substantially perpendicularly outwardly from opposite sides thereof, said ridges tapering away from said main body portion to a smaller dimension and having the outermost surfaces thereof rounded so as to facilitate deformation under load, said body member including integral flanges along one longitudinally extending edge thereof, said flanges extending laterally in opposite directions from one another, said body member having integral flanges formed along the opposite longitudinally extending edge thereof and being disposed angularly with respect to one another to define an included angle of less than 7. Support means as defined in claim 6 including sealing means disposed along opposite sides of said main body portion between said flange means.
8. Apparatus as defined in claim 7, including a layer of protective material in overlying relationship to the outer surface of each of said sealing means at opposite sides of the support means, said layer of protective material being readily separable from said sealing means.
References Cited by the Examiner UNITED STATES PATENTS 598,827 2/1898 Tracy 52627 1,833,925 1-2/1931 Weil 52396 2,083,409 6/ 1937 Stevens 52456 2,114,906 4/ 1938 Nyhagen 52396 2,141,000 12/1938 Hohl 52308 2,232,798 2/1941 Paddock 52308 2,637,995 5/1953 Mann 52125 2,991,213 7/1961 Williams 156-304 3,003,288 10/1961 Leibrook et a1 52420 FOREIGN PATENTS 100,537 12/ 1940 Sweden RICHARD W. COOKE, IR., Primary Examiner.
WILLIAM I. MUSHAKE, HENRY C. SUTHERLAND,
BENJAMIN BENDETT, Examiners.