US2486527A

US2486527A - Combined bar support and spacer

Info

Publication number: US2486527A
Application number: US530899A
Authority: US
Inventors: Hillberg Bror
Original assignee: Superior Concrete Accessories Inc
Current assignee: Superior Concrete Accessories Inc
Priority date: 1944-04-13
Filing date: 1944-04-13
Publication date: 1949-11-01
Anticipated expiration: 1966-11-01

Description

Nov. 1, 1949. B. HILLBERG COMBINED BAR-SUP PORT AND RACER Filed April 13, 1944 2 Sheets-Sheet 1 Nov. 1, 1949. B. HILLBERG COMBINED BAR SUPPORT AND SPACER 2 Sheets-Sheet 2 Filed April 13, 1944 Patented Nov. 1, 1949 COMBINED BAR SUPPORT AND SPACER Bror Hillberg, Chicago, Ill., assignor, by mcsne assignments, to Superior Concrete Accessories, Inc, Chicago, 111., a corporation of Illinois Application April 13, 1944, Serial No. 530,899

A 4 Claims.

1 The present invention relates generally to combined supports and spacers for bars. More particularly the invention relates to that type of combined support and spacer which is adapted for use in connection with the formation of a concrete structure and comprises a series of upstanding chairs which aresecured to, and spaced equidistantly along, a horizontally extending transversely disposed spacer rod and have means at the upper portions thereof for receiving and supporting a series of parallel horizontally extending longitudinally disposed bars, such :as dowel or reenforcing bars.

As evidenced by United States Patent No. 2,291,157 granted to me on July '28, 1942, it has heretofore been proposed to utilize in connection with a combined support and spacer of the aforementioned type chairs, each of which comprises (1) an upstanding wire formed, u-shaped member having the intermediate-bottom piece thereof secured to the spacer rod and its side pieces flexible laterally and extending upwardly and inwardly and bent outwards adjacent their upper extremities to form between and beneath the bent portions an open top, restricted entrance pocket for the dowel or reenforcing bar that is associated with the chair, and ('2 a separate wire formed cross member which is fixedly connected to one of the side pieces of thew-shaped member beneath its bent portion and is shaped to form an elongated horizontally extending outwardly projecting end loop at the "bottom of the pocket for supporting the bar and preventing vertical tilting thereof when his place :in the pocket, and is also shaped-to forma sideloop which extends around the other side piece of -theU-shapcd member at a point beneath its -bent portion and serves to limit or restrict outward 'ilex-ure of said other side piece in connectionwi-th insertionof the dowel or reenforcing 'bar into the pocket. In practice it has been found that although a combined support and spacer having chairs of the aforementioned character fulfills its purpose or function as a medium'for supporting and spacing dowel or reenforcing loars;it-=is,'however, subject to the objection that it does not include provision or means for positively holding *the'bars in a truly normal or rightangle position with respect to the spacer rodand as --a=result the bars are "likely in connection with' either pouringof the concrete around the combined support and spacer or mounting of the -bars-with respect to the chairs to be tilted or angularly displaced in a horizontal plane out of their proper Tightengle position with respect to the spacer rod.

One object of the invention is to provide a combined'bar support and spacer whichtisan improvement upon, and eliminates the disadvantages or defects of,--previously"designedcombined bar supports and spacersf the "same general character and-as characterized bythe tact "that the chairs thereof are provided with means for positively holding the dowel or reenforcing bars in a truly normal or right angle position with respect to the spacer rod when they are seated in the open top, restricted entrance pockets at the upper extremities of the side pieces of the U -shaped members of the chairs. 7

Another object of the invention is to provide a combined bar support and spacer of the last mentioned character in which the bar holding means are associated with and formed by the cross members of the chairs and are in the form of supplemental or auxiliary pockets which are disposed in aligned and spaced apart relation with the pockets at the upper extremities of the side pieces of the U-shaped members of the chairsand are adapted to receive the bars when they are shifted into place in the last mentioned pockets in such manner as positively to hold the vbar-s in a truly normal or right angle position with respect to the spacer rod.

Another object of the invention is to provide a combined bar support and spacer of the type and character under consideration in which the supplemental or auxiliary pockets .are formed by bending upwards the end extremities'of the wire formed cross members of the chairs so that they are in substantial alignment and parallel relation with the out bent upper extremities of the side pieces of the U-shaped members of the chairs.

Another object of the invention is to provide a combined bar support and spacer of the last mentioned character in which the portions of the wire formed cross members of the chairs that are directly inwards of the upturned pocket forming end extremities are arranged in cross relation with the result that when the side loops of the cross members are urged outwards in connection with insertion of the dowel or reenforcing bars into the main pockets between the upper out bent extremities of the side pieces of the U-shaped members of the chairs the upturned pocket forming end extremities are urged together into firm clamped or gripping relation with res spect to the bars.

A further object of the invention is to provide a combined bar support and spacer which is generally of new and improved construction, may be manufactured at a low and reasonable cost and is characterizedby-simplicity of design, and quick mounting of the dowel or reenforcing bars.

Other objects of the invention and the various advantages and characteristics of the present combined bar support and spacer will be apparent from a consideration of the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by claims at the conclusion hereof.

Figure 2 is an enlarged perspective view of one of the chairs of the combined bar support and spacer;

Figure 3 is an enlarged side view of the chair shown in Figure 2;

Figure 4 is an enlarged plan view of the chair of Figure 2 showing in detail the construction, design and arrangement of the wire formed cross member thereof and illustrating the manner in which the main pocket between the outwardly bent upper extremities of the side pieces of the U-shaped member of the chair coacts with the supplemental or auxiliary pocket between the upbent end extremities of the cross member of the chair to hold the associated dowel bar in a truly normal or right angle position with respect to the spacer rods at the bottom of the chair;

Figure 5 is a front view of the chair of Figure 2 showing the associated dowel bar seated in the main and auxiliary pockets and illustrating the manner in which the upturned cross member end extremities that form the supplemental or auxiliary pocket are urged inwards into clamped relation with the dowel bar in response to outward movement of the side loop of the cross member due to outward flexure of the outwardly bent upper extremities of the side pieces of the U-shaped member of the chair; and

Figure 6 is another front view of the chair of Figure 2 showing the chair before the associated dowel bar is seated in the two pockets.

The combined bar support and spacer which is shown in the foreground of Figure 1 constitutes the preferred form or embodiment of the invention. It is designated by the reference numeral 1 and is adapted, in conjunction with a like combined bar support and spacer ii, to be used in connection with a concrete roadway joint J consisting of a compressible filler strip 9' and a series of parallel horizontally extendin dowel bars :1. The joint is adapted for disposition between a pair of adjoining roadway forming slabs S and S on a subgrade S and, as well understood in the art, permits the slabs to expand and contract in response to changes in temperature. The strip 1 is formed of composition material and fits in an upstanding position between the two concrete slabs. The dowel bars 7' extend through holes in the central portion of the filler strip? and constitute load transfer members whereby the load on one of the slabs is transferred to the other slab. They are spaced equidistantly apart and extend lengthwise of the slabs. In addition they are located in a horizontal plane and are coated with grease or graphite so that during pouring of the concrete for the slabs the concrete will not adhere thereto. The joint also comprises in addition to the filler strip and dowel bars a set of sheet metal sleeves 7' These sleeves are slidably mounted on the ends of the dowel bars that are at one side of the strip 7' and form air pockets outwardly of such ends whereby sliding movement of the dowel bars is permitted in response to expansion of the slabs. As the result of the 4 grease or graphite which is applied to the bars the bars after setting of the slabs are free to slide longitudinally and permit the slabs to move to and from one another in response to expansion and contraction thereof.

The combined bar supports and spacers 1 and 8 constitute a unit for holding the joint in place during pouring of the concrete in connection with formation of the slabs S and S They are adapted to become permanently bonded to the concrete and serve to reenforce the slabs S and S respectively. The combined support and spacer l is located at one side of the compressible filler strip a of the joint and serves to support the adjacent ends of the dowel bars 9' The other combined support and spacer, i. e., the combined support and spacer 8 is located on the other side of the strip 1' and is associated with, and serves to support, the other ends of the dowel bars.

The combined bar support and spacer 1 is disposed in substantially parallel relation with the compressible filler strip 7' of the roadway joint J and comprises a series of chairs 9 and a pair of spacer rods Ill. The chairs underlie the adjacent ends of the dowel bars 7' and are secured as hereinafter described to the spacer rods If). The latter are spaced a small distance apart and extend horizontally. They are designed to rest on the subgrade S as shown in Figure 1, and extend in parallel relation with the compressible filler strip 51. Preferably the spacer rods Ill are formed of comparatively stiff wire. The chairs 9 are spaced equidistantly along the spacer rods I E] and correspond in number to the dowel rods 7 They are adapted to support the dowel bars in a truly horizontal plane and so that they are truly parallel to one another and are at right angles to the compressible filler strip 1'. As shown in the drawings the chairs 9 consist of upstanding U-shaped members l l and cross members [2. The U-shaped members H are formed of stiff wire of the same gauge as the spacer rods ID and comprise substantially straight horizontally extending intermediate bottom pieces l3 and upstanding side pieces [4 and [5. The lower portions of the U- shaped members H of the chairs are interposed between the spacer rods Ill and are arranged so that the bottom pieces I3 project or extend a small distance beneath the spacer rods. The junctures of the ends of the intermediate bottom pieces l3 and the lower ends of the side pieces of the U-shaped members are welded to the spacer rods l0. By reason of the fact that the bottom pieces of the U-shaped members project beneath the spacer rods they dig into the subgrade S when the combined bar support and spacer is placed in its operative position and hence lock the combined bar support and spacer against horizontal displacement in all directions. By employing two spacer rods I0 and having the lower portions of the U-shaped members of the chairs interposed between, and welded to, the rods the combined bar support and spacer I is maintained in a rigid condition and the chairs are hence retained in a true rectilinear series. The side pieces M and I5 of the U-shaped members H of the chairs are formed integrally with the ends of the intermediate bottom pieces I3. They extend upwards and inwards as shown in Figures 1, 2, 5 and 6 and have the upper extremities thereof bent outwards to form or define pockets 16 for the adjacent ends of the dowel bars 5 Such ends of the dowel bars are adapted to be inserted into the pockets by urging them or shifting them downwards between access? the upper extremities of theside pieces .of the U-shaped'members and thence past the bent portions of such extremities. By having the upper extremities of the side pieces extend outwards the :mouth portions of the pockets l6 are enlarged and hence the bars may be readily inserted into the pockets. When the bars :are in place in the pockets l6 they are disposed slightly beneath the bent portions of the :upper extremities :of the side pieces of the U-shaped membersand are secured in place by such portions. The cross members $2 of the chairs 9 are disposed beneath the bent portions'of the upper extremities of the side pieces I 4 and I5 of the U-shaped members and are formed of stifi wire of the same gauge as the U shaped members. They are bent or otherwise deformed so that they include fiat horizontally extending end loops l1 and pairs of opposed side loops l8 and I9. The end loops IT project outwards-oi the U-shaped members H and form -'horizontal seats for the lower portions of the adjacent ends of the dowel bars 7' when such ends are in place in the pockets l-S. They are vformed from the central portions of the wires of which the cross members are formed and are of such length that when the-adjacent ends of the dowel bars .are in place in the pockets the bars are precluded from tilting vertically relatively to the chairs. The side loops l 8 are located at one side of, and are joined to and formed integrally with, the outwardly projecting end loops 11. They are disposed outwards of and around the side pieces l4 oftlieU-shaped members II and are welded to such side pieces in-order fixedly or rigidly to connect the cross members l2 to the U-shaped members 1 l. side loops l9 are located at the other side of the end loops l1 and are positioned in opposed-relation with the side loops I8. They are joined to, and formed integrally with, the outwardly rprojecting end loops l-l, surround the side pieces Li of the U-shaped members H, and serve so :to re strict outward flexure or swing of such' side pieces that the adjacent ends of the dowel bars, when in the pockets 16, are securely held in place against the end loops l5 and between the bent portions of the upper extremities "of the "

side pieces

14 and 15. As shownrin Figures and 6, the side loops L9 are-normally so spaced from the side loops 8 that when the adjacent portions of the side pieces [5 are inabutment Jthereagainst the bent portions of the side pieces EM and i5 are spaced apart a distance slightly less than the diameter of the dowel bars. As the result of this the dowel bars must be forcibly shifted downwards into the pockets past the bentportions of the upper extremities of the side-pieces l4 and I5 and when in place are urged oripnessed downwards by the bent portions of the side pieces of the U-shaped members into flat seated relation with the end loops I 1. Such end loops permit the side loops l8 and 19 to flex outwards away from one another in connection with insertionof the adjacent ends of the dowel bars into the pockets IS. The ends of the cross members [2 are designated in the drawings by the reference numerals 2!! and 2! and project inwards with respect to the upper portions of the U-shaped members H of the chairs 9. As shown in Figure 3, the'ends'2ll of'the cross members are horizontally aligned with the-zend loops It?! and serve as additional supports or seats for the adjacent ends of the dowel bars 7' when such ;ends are seated :in the pockets IS. The ends Zllof the cross members are joined to, and formed integrally with the loops [8 and extend at substan- The tia-lly an angle 20f 45 withmespect to the rods -l0,as.shown in Figure 4. The extremities of the ends 20-.are'bent upwards so that ltheyware substantially aligned with 'the outwandly :berrt upper extremities of the side zzpieces 1:5 olf Lthe '.U-- shaped members H. The ends .2I of the formed cross members .12 are joined to, zandtormed integrally 'with,-the end loops 1:9 and underlie, and are arranged in crossed relation with, the ends 20. They'extend atrsubstantiallya 45atngl'e with respect to the spacer rods Ml and-:zhave' the outer extremities thereof bent upwards sothat they are substantially aligned with the 'outwazrdl'y bent upper extremities of the :side 111116085 14 :of the U-shaped members "I I. The up bent extnemie ties of the ends 228 and El define supplementalior auxiliary ,open 'top pockets .22 lor "the adjacent ends of the dowel bars 5 ':Such pockets are aligned with the pockets l6 and lcoact'with'rthe latter pockets in such manner that when adjacent ends of the dowel bars :are-ziniplalce the bars are positively held at right angles to the spacer rods l '0. By providing the auxiliary pockets 22 whereby the :dowel rods are positiuely held truly normal or at right angles to the spacer rods Ill the dowel bars ane maintained:in'iparallel relation and at true rightiangles "withrespect to the compressible fillerstrip "Preferably the bent extremities of the :ends :2'0 and .2;4 vof the cross members are arranged so that theyraresupwardly divergent in order readily to receiue the adjacent ends .o'f'the dowel'bars win connection with insertion of the latter into the pockets :22- Because the ends 2t] zandt2 I of'the-zcross members are arranged in crossed relation the supfbent extremities thereof are urged inwards: "intoclamped relation with the adjacent ends of :it-he dowel :bars in response to outward flexing of 'the'side sleeps [8 and I9 due to insertion of said adjzacentiends of the dowel bars into'thepockets H5.

The combined bar support zandispa-cer Ben the opposite side ofthe compressible filler-strip '7 is exactly the same :in design .and construction aas the combined bar support and spacer Ii. :It operates as hereinbefore described, :to support the adjacent ends of the dowel ibarsx j 'zand consists of a rectilinear series of equi'distant'ly spaced chairs 23 andaipairbf "parallel horizontally :extending spacer rods 2-4. The spacer rods are adapted to rest on thexsubg rade S andare spaced a small distance apart. Thechairs 23are cornstructedsimilarly .to the chairsfi ro'f the combined bar support and spacer "I and -consists=of upstanding U shaped members 25 and'cross-members 2153. The .U-shaped members 25 are aligned with the U-shaped members II of the chairs 9 and have the lower portions thereof interposed between, and welded to, :thespacer rods 24.. The cross members 26 :of the chairs 23 are the same in design as the cross members l2 .of the chairs 9 and are arranged so'that the end loopsthereof pro ject outwards and their crossed ends with the up turned "pocket forming extremities project inwards.

In assembling the joint and unit of Figure 1 the'combined'bar supports and spacers l and 8 are arranged in parallel relation'and so that they extend transversely of the subgrade :8 In connection with positioning of the "combined Ibar supports and spacers the latter are arranged in parallel'relation and are spaced apart a distance less than the length'o'f'the dowel bars. After'the combined bar'supportsand spacers are properly arranged With-respect tothe subgrade the dowel bars 7' are'inserte'd through the holesin the central portions of the compressible filler strip 1' and the filler strip and bars are manipulated so as to bring the lower margin of the strip into abutment with the subgrade and the ends of the dowel bars into seated relation with the pockets at the upper ends of the chairs. The bars are brought into seated relation with the pockets by forcing the ends thereof downwards as heretofore described. In connection with downward shift of the dowel bars the intermediate bottom pieces of the U-shaped members of the chairs are forced into the subgrade S so that they serve to hold the unit in place. When the dowel bars are in seated relation with the pockets they are maintained by the combined supports and spacers 1 and 8 in a truly horizontal position and also at true right angles to the compressible filler strip y. After assembly of the joint and unit concrete is poured at the sides of the strip to form the roadway slabs S and S After setting of the concrete the dowel bars form load transfer members as heretofore pointed out. By reason of the fact that each chair is provided with two pockets there is no likelihood of either of the combined bar supports and spacers moving lengthwise with respect to the other combined bar support and spacer in connection with either assembly of the unit or pouring of the concrete at the sides of the compressible filler strip.

The herein described combined bar support and spacer is essentially simple in design and hence may be manufactured at a low and reasonable cost. It effectively and efiiciently fulfills its intended purpose and is characterized by the fact that the double pocket arrangement at the upper portions of the chairs serves positively to hold the bars so that they are truly normal or at right angles to the spacer rods at the bottom portions of the chairs.

Whereas the combine bar support and spacer has been described as adapted for use in conjunction with a complemental combined support and spacer to form a unit for use in connection with a concrete roadway joint it is to be understood that the invention contemplates a single combined bar support and spacer having other capabilities of use. It is also to be understood that the invention comprehends a single bar supporting chair like that shown in Figure 2, and is not to be restricted to the details set forth since these may be modified within the scope of the appended claims without departing from the spirit and scope of the invention.

2. As a new article of manufacture, a dowel bar supporting chair comprising a U-shaped member the lower portion of which converges inwardly and the upper portion of which diverges outwardly, and a wire cross member positioned beneath the diverging upper portion of said U- shaped member and adapted to form a dowel bar receiving pocket therewith, said cross member including a pair of opposed side loops one of which is connected to a leg of the U-shaped member, and end portions projecting from said loops in crossed relationship and terminating in upwardly bent extremities which form a second dowel bar receiving pocket parallel to the first mentioned pocket, said upwardly bent extremities being movable inwardly into dowel bar clamping relationship when the side portions of said first mentioned pocket are spread outwardly upon insertion of a dowel bar therein.

3. As a new article of manufacture, a dowel bar supporting chair comprising a U-shaped member the lower portion of which converges inwardly and theupper portion of which diverges outwardly, and a wire cross member connected to said U-shaped member beneath the diverging upper portion thereof to form a dowel bar receivingpocket therewith, said cross member including end portions projecting from the side portions of the pocket in crossed relationship and terminating in upwardly bent extremities which form a second dowel bar receiving pocket parallel to the first mentioned pocket, said upwardly bent extremities being movable inwardly into dowel bar clamping relationship when the side portions of said first mentioned pocket are spread outwardly upon insertion of a dowel bar.

4. As a new article of manufacture, a combined support and spacer for parallel substantially horizontal dowel bars, comprising a horizontal spacer rod adapted to be positioned beneath, and at right angles to, the bars. and a rectilinear series of laterally spaced chairs corresponding in number to, and adapted to be associated respectively with, the bars and each consisting of a U-shaped member the lower portion of which converges inwardly and the upper portion of which diverges outwardly, and a wire cross member connected to said U-shaped member beneath the diverging upper portion thereof to form a dowel bar receiving pocket therewith, said cross Having thus described the invention what I 7 claim as new and desire to secure by Letters Patent is:

1. As a new article of manufacture, a dowel bar supporting chair comprising a U-shaped member the lower portion of which converges inwardly and the upper portion of which diverges outwardly, and a wire cross member connected to said U-shaped member beneath the diverging upper portion thereof to form a dowel bar receiving pocket therewith, said cross member including a flat outwardly projecting end loop, a pair of opposed side loops one of which is connected to a leg of the U-shaped member, and end portions projecting from the side loops in crossed relationship and terminating in upwardly bent extremities which form a second dowel bar receiving pocket parallel to the first mentioned pocket, said upwardly bent extremitiesbeing movable inwardly into dowel bar clamping relationship when the side portions of said first mentioned pocket are spread outwardly upon inser tion of a dowel bar.

'Ill

member including a. flat outwardly projecting end loop, a pair of opposed side loops one of which is connected to a leg of the U -shaped member, and end portions projecting from the side loops in crossed relationship and terminating in upwardly bent extremities which form a second dowel bar receiving pocket parallel to the first mentioned pocket, said upwardly bent extremities being movable inwardly into dowel bar clamping relation:

! ship when the-side portions of said first mentioned pocket are spread outwardly upon insertion of a dowel bar.

BROR, HILLBERG.

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

UNITED STATES PATENTS Number Name Date 1,637,742 Edge et a1. Aug. 2, 1927 2,064,705 Whitehead Dec. 15, 1936 2,133,553 Lord Oct. 18, 1938 2,291,157 Hillberg July 28, 1942