US2461733A - Clamp for cement form panels - Google Patents

Description

CLAMP FOR CEMENT FORM PANELS Filed April 4, 1947 F/GJ l: /0 F/G. 4.

magg' INVENTOR.

- ARM RJHARDER BY. V'

Patented Feb. 15, 1949 UNITED STATES PATENT OFFICE i Claims. (Cl. .Z5-131) The present invention relates to panel clamps. In building concrete walls a plurality of panels, usually of rectangular formation and made of plywood, is used. Such panels are arranged in an edge to edge position on each side of va concrete wall to be built, with the two planes of the panels arranged parallelly and maintained in mutually rigid condition to receive cement mixture, which upon its setting forms a concrete wall. Usually said panels, along their margins are provided with metallic angle members which in a pair of adjacent panels are rigidly engaged for maintaining the adjacent panels in an inter locked rigid mutual relation for forming a form on each side of a concrete wall to be built preparatory to the cement pouring operation, Therefore, the principal object of the present invention is the provision of a suitable clamp, of a comparatively simple construction for engaging the angle members in the adjacent panels for maintaining the latter in a rigid mutual position, and which are easy to apply to said angle members when the form is being built, and which are easy to disengage when the cement has solidified, preparatory to the dismantling of the form.

Usually a pair of spaced form walls built of the panels aforesaid are maintained in a rigid mutual position by `a plurality of metallic ties, positioned transversely of the built form. Such ties are usually rigidly connected to each panel wall for maintaining the twor in a rigid mutual position for preventing yielding when under the pressure of the poured cement.. The ties are usually provided at their ends with a rather complicated mechanism for engaging the form walls.y `The ties necessarily remain embedded in the y y locks the adjacent panels at their joints formed by a pair of said angle members,4 and engages the tie in a rigid grip and holdsA the same in a rigid interlocked position with relationv to the panel. This double function is performed by a single operation as the tie is applied to the form. Also, the disengaging operation of the clamp from the form simultaneously releases its hold upon the panel joint as well as upon the tie.

' With the above general objects in view and others that will appear as the invention is better understood, the same consists in the novel construction, combination and arrangement of parts hereinafter more fully described, illustrated in theV accompanying drawing and pointed out in the appended claims.

In the drawing forming a part of this application and in which like designating characters refer to corresponding parts throughout the several views:

Fig. 1 is a top elevational view of the clamp in it? operative position with the Panel joint and a 1e;

Fig. 2 is a side elevational view of the clamp in the same position;

Fig. 3 is an edge elevational view thereof; and

Fig. 4 is a cross-sectional view thereof on line 4 4 of Fig. 2.

Referring to the present drawing there is shown a plurality of panels I 0 arranged in an edge to edge position for providing a form wall on each side of a concrete wall to be built. When a pair of such form walls is constructed cement II is poured therebetween which upon setting forms a concrete wall. When the cement has solidified the form walls built of said panels I0 is dismantled and taken away from the nished l. concrete wall.

Sai-d panels Il) are usually made of plywood and each is of a rectangular formation. Each of said panels lli is ordinarily provided with angle member i2 rigidly affixed to the panel and ad- 4jacent its margins on all four sides thereof. Portions of said angle members I2 which are in a vertical relation with the body of the panels form a joint in two adjacent panels which when rigidly engaged will maintain the adjacent panels in an interlocked rigid mutual position. The joint referred to is indicated by I3.

' A plurality of ties I4 are applied to a pair of form walls consisting of said panels IB and by each of their ends bound to each form wall for maintaining the two in a rigid mutual position, preventing their yielding away from each other when under pressure of the cement poured therebetween or during the setting thereof. Each of said ties i4 is preferably made of metal and has a form of an oblong narrow strip and comparatively thin. The length of each tie I4 corresponds to the combined width of the space between the form walls, the thickness of the panels and the width of the outwardly projecting portions of angle members I2.

The clamp constituting the subject-matter of the present invention is designed for the purpose 0f interlocking joint I3 dened by the outwardly projecting portions of the adjacent angle members I2 in any adjacent pair of panels lil when laid in an edge to edge relation on a common plane, as seen in Fig. 1, and for engaging the end of tie Hl for rigidly binding the same to joint i3 and thereby to the form wall dened by a plurality of panels [il arranged in a coe planary relation, on each side of a concrete wall to be built, and inclu-des a substantially U-shaped housing I5. The latter is formed of side walls I6 and i?, which by one of theirends are connected by end wall i8. Side wall I6 terminates on the plane of the outer terminations of angle members I2 when the clamp is in an operative position with joint I3, as best seen in Fig. 4, while side wall I'I is extended farther and on its inner face is provided with an integrally -formedand laterally directed lug I9, which contacts with and bears against the adjacent face 'of *one angle member I2 when the clamp is in an operative position with joint I3, as seen in Fig, 4.

integrally formed with said housing I5, ad-

jacent its lower end, and downwardly depending therefrom is block 2li, therear end of which connects with the lower end of rear wall `I8 and the adjacent portions of side Walls I6 and Ii through horizontal wall 2i which is vprovided with aperture 22 for the purpose later described. The width of said block 2o is narrower than thewidthof said housing I5, yone side wall thereof .being the downward continuation of side wall I6, while the opposite side wall thereof is spaced away from the adjacent sidewall I'l of housing I5 and disposed nearer towards the center of the clampas seenin lFig.3. The upper vfront portion of block 2G, between walls I6 and II, remains flush with the corresponding termination of `side wall I6, as at 28, so that the former remains in contact with joint I3 in the operative position of the Vclamp therewith, as seen in Figs. 2 and 4. However, the lowerfr'ont portion of said block '20 terminates sho-rt of the free end of joint i3,

plane said block is provided with recess 25 for receiving therewithin lower, stationary, tieengaging jaw '2b. Said recess 25 .does not bisect the rear wall of Vsaid block 2'0, so that said jaw '26 bears thereagainst, asis seen in Fig. '2. Said Yjaw 2E is rigidly .anchored within block ZI] and housing I5 by means of a pair of pins 21 and 28, the former passing `through side walls I6 and I'I of housing .I.5,'the upper end of block 20 and said jaw 2G, while the latter passing through the lower end of block 'mand jaw '26, bothin Va transverse relation. Y

To digress at this point from a .further description .of the clamp, tie Ill, adjacent its end and along its edges is provided with opposed teeth 2S. The tie .by its end, including teeth 29is receivable between the adjacent angle members I2 at joint I3, thereby maintaining said angle members I2 and themargins of adjacent panels in a spaced relation. The spaces dened thereby are very narrow corresponding to the width of tie Hi, which however are not sufficiently wide to permit leakage of the cement to any undesirable degree.

As is clearly seen in Fig. 2, said stationary jaw '26 enters by its free end into the recess defined by the adjacent portions of angle members I2, and from one edge of tie I4 to engage the adjacent teeth by correspondingly formed teeth 3E! upon the upper edge of said jaw 26.

Receivable between walls I6 and I'I of housing i5, and above the upper end o-f block 2li is the inner end .of shank of rlever 3 I which is journaled upon pivot pin .32 for angular Yshifting movement. One face of said lever 3l contactsthe inner face of said side wall Iof housing I5, whiletheopposite face thereof is in a spaced relation with the adjacent inner face of side wall II, and in order to substantially completely lill the space between said walls i6 and I'I, and to prevent thereby said lever 3i Yfrom lateral shifting movement upon pin Si. the lsame is provided with an integrally formed and laterally projecting hub 33, which is interposed between the body portion of said lever 3i and wall I7, allowing however sufficient space for seating between said hub 33 and wall il' of L- shaped leaf spring 34, for the purpose hereinafter specied. Y

Said rlever 3l is longitudinally and centrally recessed for receiving therewithin jaw 35 which is rigidly anixed to saidlever by means of a pair of transverse pins 3S passing through said lever 3l and saidjaw 35. 'Said jaw is provided on its .inner edge withteeth'i for engaging the adjacent teeth 29 made in tie III. Both 'said jaws 26 and 35 are in alinement and of the same width co1'- responding to the'width of tie I4,.and both are adapted toenter the recess between angle members l2, and to engage said tie fromthe opposite edges 'through teeth .29 made in the tie `and correspondingly formed'teeth 3G and B'Imade in jaws 25 and 35, respectively.

The upper freeend of lever 3l haga laterally enlarged head', from which apair of spaced joint-engaging extensions 39 project. The inner faces of said'extensions areat opposed inclines as at 3.50, vtlierebyefecting substantially V-shaped recess within which the free end portions .of angle members .l2 at joint Iare receivable. Due kto said inclined faces '40, whenpressure is applied to head 22, the adjacent pair of free portions of angle'members I2 are flexed toward each other, as their outer faces are forced to ride upon the inclined inner faces 'of said extensions 39, until joint 3 is forced into the recess defined by said extensions 39, thereby effecting a rigid andtight .interlocking between extensions 39 and joint I3. It is of course assumed that during the above 'operation the clamp is already in eng-agement with tie i4 by virtue of the engagement of teeth i3@ in stationary jaw 26' with teeth 29 in tie I4.

Lever '3l is capable of angular shiftingmovement upon pin 32 as is indicated by .dotted lines in Fig. 2, and when said extensions 39 are brought to an Yoperative position with joint I3, as aforesaid, and as shown in fulllines inIFig. 2, said jaw 35 is simultaneously shiftedinto the .recess defined by a pair of freeportions ofadjacent angle members i2 until Vteeth 37 thereof spring into engagement with .teeth .29 at the edge of said tie Ill opposite from that at which jaw 2t engages the same. When both jaws 2S and 35 are in engagement with tie I4, extensions 39 are .rigid with joint I3, andthe .clamp is in an interlocked relation withsaid tie I i and joint I3, and no ordinary jarring will suice rto dislodge the interengagement.

When the concrete wall has set and the form walls are ready to be removed therefrom, a crowbar or similar .instrument is inserted between tongue 4I and the adjacent edges of angle Imembers I2, and angularly shifted until teeth 31 of jaw 35 are Vforced out of engagement with teeth 29 in tie I4. When this is accomplished extensions 355 are then shifted away from joint I3.

' Push of the clamp .in .a direction which tends to be hit by a hammer at its outer end wall; the space defined by recess 24 will permit angular sluiting of said block 20 and of the clamp for dislodging jaw 26 from its engagement with the teeth in tie I4. When this is done-the clamp will be completely diseng-aged from joint I3 as well as from tie I4, and when all clamps are removed from all panels III and ties I4, said panels I0 are then ready to be taken away from the completed concrete wall.

When the clamp remains in an engagement with joint I3 through extensions 39, to guard against accidental opening of the clamp, that is against angular shifting of lever 3l away from joint I3, a nail or spike may be inserted into aperture 22, which, bearing against lever 3l or head 38, or being in the path thereof, will prevent the angular shifting of said lever 3I and of the head 38, and consequent disengagement of extensions 39 from joint I3. v c

Referring to spring 34, its body portion is interposed between hub 33 and the adjacent face of side wall II, and rests by its one edge upon the inner end of block 2li. Pin 32 also passes through it and maintains it in stationary position. The c operative end of said spring 34, substantiallyin a perpendicular relation with the body portion thereof, is positioned for flexing movement above the upper end of block 20 and within the space defined by the free ends of walls IIi and I'I, lug IS, adjacent end of lever 3l and hub 33. The outer termination o-f said opreative end of Spring 34 tends to flex beyond the plane of the free end of wall I6, and has loop 42 which normally extends beyond the said plane, being urged into that position by the inherent flexing action of the said operative end of said spring 34. The space defined as aforesaid affords the room for flexing action of the said operative end of .said spring 34. v

Cooperating with the free end of wall I 'I and lug I9 is screw 43 having knurled knob 44. Assuming that one panel I0 has already been set in a vertical position at the commencement of form Wall erecting operation, with no side panel on the side thereof in an edge to edge relation, tie I4 is first applied to said panel I!) in an edge contact therewith and at the vertical edge thereof,

wardly projecting leg of angle rmember I2. While manually holding the tie in that position, with the end thereof flush with the outer edge of the outwardly extending leg portion of said'angle member, as is seen in Fig 4, the clamp is then applied to the said leg portion and tie I4, by bringing the stationary jaw 26 below the lower edge of tie I4 for engaging teeth 3E with the corresponding teeth 29 in tie I4, as seen in Fig, 2. In this position of the clamp the free end of wall I'I will remain in a transverse relation with the outwardly extending leg portion of said angle member I2, with lug I9. in the proximity of the -adjacent face of said outwardly extending leg portion of angle member I2, as is seen in Fig. 4. Thereupon screwl 43 istightened by turning knob 44 for bringing the free, inner end of said screw 43 in engagement with said adjacent face of the outwardly extending leg portion of member I2, as is apparent from the showing in Fig. 4. In cooperation with said lower, stationary jaw 26 said screw 43 clamps the interposed outwardly extending leg portion of said angle member I2, for maintaining the entire clamp in a rigid association with a single outwardly extending leg portionof angle member I2 of that one panel I0 already set up in a vertical position while com.-

aeeigvsa I the same being of course in contact with the outmencing the erection of form wall aforesaid. The identical procedure for aflixing the clamp through the medium of screw 43 and for engaging jaw 26 with the lower edge of tie I4 at one end thereof simultaneously takes place at the opposite end of tie I4 at the other opposite form wall being formed in the spaced relation with the rst one, thereby supporting said tie I4 at both of its ends upon jaws '26 in the two clamps employed.

From the hereinabove description it will therefore be apparent that due to the procedure last hereinabove described the clamp is already in an engagement with` the outwardly extending leg portion of angle member I2 in single panel I4, with tie I4 supported on a vertical plane by means of jaw 26 engaging said tie I4 at its lower edge. The lateral support of tie I4, and the contact thereof with the adjacent edge of panel Ill and with the outwardly extending portion of angle member I2, is had through the medium of loop 42 of the operative end of spring 34, asis clearly seen in Fig. 4,

While the clamp is maintained in a rigid engagement with the outwardly extending legportion of angle member I2 of a single panel Ill, as aforesaid, the next panel I!) is bodily brought to the first one to lay the two in an edge to edge relation. Said last named panel IIJ is preferably brought to the rst one from within the space dened by two form walls being constructed, that is from the space into which eventually the cement will be poured upon completion of the erection process of -a pair of form walls. The shifting of said latter panel IEI into its operative position with relation to the rst one, will bring the outwardly extending leg portions of angle members I2 in the two panels into a mutual, cooperative position for forming joint I3, as seen in Fig. 1. During the shifting of said last named panel into its cooperative relation with the rst one, the outwardly extending leg portion of angle memb-er I2 of said last named panel I!! will strike loop 42 of spring 34, deflecting the operative end thereof awa-y from the adjacent edgesof joint I3. At this point the function of said loop 42 terminates, because the adjacent edge of newly posi-Y tioned panel I il with the outwardly extending leg portion of its angle member I2 will provide lateral support for tie I4. When joint I3 has been formed spring 34 is deflected as aforesaid and remains inoperative, while screw 43 will continue to remain in its engagement with the adjacent face of theoutwardly projecting leg portion of angle member I2 vwith which the same was originally brought into engagement, for preventing the downward shifting of jaw '26 and the disengagement of its teeth with teeth 29 at the lower edge of tie I4.

While said engagement of lower jaw 26 with tie I4 is maintained as aforesaid, lever 3l is shifted upon its pivot pin 32 for bringing head 38 into its operative position with the newly formed joint I3, with extensions 39 in an operative position with said joint I3, as indicated by full lines in Fig. 2.

Although all clamps are of identical construction, al1 having springs 34, and are to be used interchangeably, and without regard as to whether the same are applied at vertical or horizontal fammes under i-construction, need no preliminary lateral support Vas ties I4 kat the .vertical edges ofpanels l0 do.

When jaws 2S and 35,'andtheir'respective teeth 3b and 3l, become damaged'or worn out the jaws may be removed from block 2Q and lever respectively, upon removal of pins 21,2andl3t, and'new jaws substitutedin their stead.

When concrete wall has been built between a pair of spaced -orm walls 'made of panels gli), 'one one each side of a concrete wall, said form walls will 'then be ready to be dismantled and panels 'iD removed from the nis'hed concrete wall. To dismantle the form walls,.;iirst .the clamps are removed from all joints i3, and this is done by irst removing rnail or spike `from .aperture 22. Then head 38 with extensions '39 is shifted out of engagement with joint i3, vwhich operation simultaneously disengages jaw 35 from engagement with the teeth at the adjacent edge oi :tie I4. Thereupon screw fis Yisdisengaged from fthe adjacent outwardly projecting Vleg portion iof angle member i2. When all of said ,clamps have been :removed from their joints I3, with stationary jaws 26 pried out of engagement with teeth 29 of tie Utley hitting the end wall of block 253 with a hammer, thereby permitting shifting of the clamps to the extent allowed by recess `Nl, -as hereinabove described, all panels i9 are thenremoved from `contact with the nished concrete upon the edges thereof, by afharnmer, the tie willv break along the line of a pair .of Aopposed notches 45. The resulting crevice made in the concrete wall may be iilled with cement inorder to make the surfaces of the concrete wall smooth. Of course, the central portions of ties I 4, upon breaking their ends as aforesaid, will remain yembedded within the concrete wall.

From the hereinabove description it'will be'apparent that during the construction of form walls on each side of a concrete wall to .be`.1built, no difculty will be encountered in applying jaws 2.5 and 35 to their engagement with therespective teeth 29 `in tie ifi. When however `cement `has been pouredbetween a pair of erected forinwalls, the same will exert pressure in lateral direction and upon the inner faces of panels min the'two form walls. This pressure will tend to drawieach f pairof the opposed clamps cooperating with each tie into the opposite directions and in a longitudinal direction with relation to tie it, thereby tending to increase the grip of jaws 2.5 and 35 by their respective teeth S and 31 upon 'teeth l29 at each end of tie Ed. The greater this pressure, the greater the grip-ping engagement between jaws 25 and 35 with each'end of tie M. Due vto this reason it is necessary to `use an instrument by interposing the same between tongue ii and the adjacent edge of joint I3 to swing lever 3E away from joint i3 and extensions 'dii out of their operative engagement therewith, as well as to pry jaw 25 out of engagement `with theopposite teeth at tie It by hitting the end wall of block 2t by a hammer, as a preliminary step tothe removal of the clamp from joint I 3.

Ii preferred, the marginal edges of panels .m may be slightly extended beyond the outer plane .of ,the outwardly extending leg portion Vof .angle Y' lil members |2,":with`recesses 46 `made inthe v.mar-- gins Aoipanels l0 for accommodating therewithin tie Hi. Said extended marginal portions of panels i@ will contact in a pair of adjacent panels l0, along line ci, the two panels accommodating tie .I4 lwithin their .recesses 46, thereby avoiding the crevice between the Aadjacent panels and com- -pletelypreventing leaking of the cement.

While there is described herein a preferred embodiment of the present invention, it isrnevertheless vto be .understood'that minor changes may be made therein "without departing from the spirit and scope of the invention as claimed.

What I claimas new is: v

1. A clamp of theclass described'comprisinga base, a jaw in a stationary relationtherewith, a

'.swingable member in a pivotal relation with said `base,.a pair of clamping membersat the free end 2. `A clamp of the class described comprising a base, a jaw in a stationary relation therewith, ,a swingable member in a pivotal relation with said base, a pair-of clamping members at the free `end of said swingable member, and a jaw connected with said swingable member intermediately of said base and said clamping members, the operative edges of said jaws remaining substantially in a parallel relation when said swingable member is swung into an operative position, said jaws being o-n a plane substantially median of saidclamping members.

`3. A clamp of the class described comprising Va base,'a ljaw in a stationary relation therewith, a swingable member in a pivotalrelation with rsaid base, a pair of clamping merribersat the free end of said swingable member,a jaw connected with said swingab-le member intermediately of `said base and said clamping members, a projection extending from .saidbase ina substantiallyparallel relation with said rst named jaw, and an `adjusting member in said projection ,coacting with said iirst named jaw in a transverse relation therewith.

`4. A clamp of the class describedcomprising a base,a jaw in a stationary relation therewith, a swingable member in a pivotal relation with said base, a pair :of clamping members at'thelfree end of said swingable member, a jaw connected with said swingable member: intermediately of said base and said clamping members, the operative edges of said jaws remaining substantially in a yparallel vrelation when said swingable memberis swung into an operative position, a projection extending-from said base in a spaced relation with said rstnamed jaw, and an adjustable clamping screw `in said .projection coasting with said rst named jaw in aplane perpendicular to the plane upon'which both of said jaws coact. 5. fi .clamp or the class described comprising a base, a jaw in a stationary relation therewith, a

'swingable member, a projection extending from said base in a spaced relation 'with said "first named jaw, an Aadjustable Aclamping member in said projection coacting with said :firstnamed jaw ina `transverse `relation `-to Vsaid rst named plane, and a yieldable retaining member connected to said base, said yieldable retaining member being on a plane coextensive with the plane of the face of said 'first named jaw which is opposite from the plane which is coextensive with the face thereof adjacent said projection.

6. In a concrete form, including a pair of spaced form walls for receiving therebetween cement mixture which uponsetting forms a concrete wall, a plurality of panels, said panels dening said form walls when arrangedin an edge to edge relation, a plurality of ties, each of said ties consisting of an oblong, comparatively narrow strip of material, each end of each tie being passed between a pair of adjacent panels in each form wall, the wider faces of said ties being in contact with the adjacent edges of a'pair of adjacent panels at each end of each tie, the edges of the adjacent pair of panels eiecting a recess corresponding in width to the thickness of the tie therebetween, a clamping member insertable within said recess for engaging each tie at the opposite edges thereof, and means associated with said clamping member for binding the latter to said adjacent pair of panels at each form wall.

7. In a `concrete form, including a pair of spaced form walls for receiving therebetween cement mixture which upon setting forms a concrete wall, a plurality of panels, said panels defining said form walls when arranged in an edge to edge relation, a plurality of ties, each of said ties consisting of an oblong, comparatively narrow strip of material, each end of each tie being passed between a pair of adjacent panels in each form wall, the wider faces of said ties being in contact with the adjacent edges of a pair of adjacent panels at each end of each tie, the edges of the adjacent pair of panels effecting a recess corresponding in width to the thickness of the tie therebetween, a clamping member, a pair of jaws associated therewith, said jaws being insertable within said recess for gripping each tie at the opposite edges thereof, and means associated with said clamping member for binding the latter to said adjacent pair of panels at each form wall.

8. In a concrete form, including a pair of spaced form walls for receiving therebetweencerment mixture which upon setting forms a concretewall, a plurality of panels, said panels defining said form walls when arranged in an edge to edge relation, an angle member rigidly aiiixed to each panel adjacent the margin thereof,fthe outwardly extending leg portion of said angle member in each panel being substantially in a f perpendicular relation with the body of the panel, a plurality of tieseach of said ties consisting of an oblong, comparatively narrow strip of material, each end of each tie being passed between the outwardly extending leg portions of said angle members in each pair of adjacent panels in each form wall, whereby said outwardly extending leg portions of said angle members' contact with the wider faces of each of said ties, and define a recess corresponding in width to the thickness of the retained tie, a clamping member, a pair of jaws carried by said clamping member, said jaws entering said recess Vfor gripping each end ofY each tie adjacent the opposite edges of each tie, and means associated with said clamping member for rigidly engaging on a transverse plane a. pair of the adjacent outwardly extending leg portions of said angle members -in a pair of adjacent panels for binding the tie to the latter and for maintaining a pair of adjacent panels in a rigid operative relation.

9. In the art of setting up form walls for receiving therebetween a cement mixture which on setting forms a concrete wall, a plurality of ties for maintaining a pair of form walls in a spaced, bound relation, a plurality of panels, which, when arranged in an edge to edge relation defining one of said form walls, a base member, means associated therewith for .temporarily supporting the same upon one of said panels, means carried by said base member for temporarily laterally rengaging the tie and holding the same in contact with a Vertical edge of said one panel, as the adjacent panel is brought to said one panel in an edgev to edge relation said newly set panel rendering said last named means inoperative, the tie being then laterally supportedby the two panels, means carried by said base member for rigidly engaging the end of the tie, and means for rigidly engaging said base member with the two set panels.

10. In the art of setting up form walls for receiving therebetween a cement mixture which on setting forms a concrete wall, a plurality of ties for maintaining a pair of form walls in a spaced, bound relation, aplurality oi panels, which, when arranged in an edge to edge rela tion defining one of said form walls, abase member, means associated therewith for temporarily supporting the same upon one of said panels, means carried by said base member for temporarily laterally engaging the tie and holding the same in contact with a vertical edge of said one panel, as the adjacent panel is brought to said one panel in an edge to edge relation said newly set panel rendering said last named means inoperative, the tie being then laterally supported by the two panels, means carried by said base member for rigidly engaging the end of the tie through the recess formed by the edges of the two adjacent panels resulting from the interposition of the tie, therebetween, and* means rfor rigidly engaging said base member with the two set panels for binding the tie thereto and for mutually interlocking the two set panels.

ARTHUR J HARDER.

REFERENCES CITED The following references are of record in thel file `of this patent:

UNITED y STATES PATENTS

Images