Patent Publication Number: US-3880397-A

Title: Bowed tie rod with deformable cone means

Description:
United States Patent 1 1 Becker 3 1 1 Apr. 29, 1975 1 1 BOWED TIE ROD WITH DEFORMABLE CONE MEANS [75] Inventor: Donald E. Becker, Kenosha. Wis.  
 [73] Assignee: Becker, Inc., Kenosha. Wis.  
 [22] Filed: July 16, 1973 [21] Appl. No.: 379,681  
 [52] US. Cl 249/214; 249/46 [51} Int. Cl. E04g 17/08 [58] Field of Search 249/40-41, 249/43,46,190-191.2132l4.216217. 219 W [561 References Cited UNITED STATES PATENTS 2,898,659 8/1959 Shoemaker 249/219 W 2.967.689 1/1961 Jahn 249/219 W 3013.323 12/1961 Williams. 249/217 3.235.217 2/1966 Jahn 49/219 W 3,638,904 2/1972 Franklin et al. 249/40 3.693.931- 9/1972 Holt 249/46 3.729.166 4/1973 Buykcn et al... 249/190 3.746.297 7/1973 Daniels. Jr. 249/214 Primary Examiner-Robert D. Baldwin Assistant Examiner-John MCQuade Attorney, Agent. or Firm-Arthur L. Morsell. Jr.  
 [&#39;57] ABSTRACT The end of a sna ppable concrete form tie rod extends through an opening in a concrete form panel. The tie rod has a weakened portion at which its end may be snapped off after the concrete has hardened. The end of the tie rod is flattened adjacent to the head thereof. one end of the flattened portion forming a shoulder which engages a bracket for holding the tie rod in position. The flattened portion may be engaged by a wrench for applying torque to the end of the tie rod to snap it off. A cone member is positioned on the tie rod between the weakened portion and the head. The cone member has a central opening extending lengthwise therethrough which is somewhat larger in diameter than the tie rod for slideably receiving the same. The tie rod has an outwardly bowed portion between the weakened portion thereof and the head to bind the cone member in a predetermined position on the tie rod.  
 3 Claims, 5 Drawing Figures BOWED TIE ROD WITH DEFORMABLE CONE MEANS BACKGROUND OF THE INVENTION This invention relates to snappable concrete form tie rods which are used to hold the sides of a concrete form together while the concrete therein is hardening and are then snapped off at the ends after the concrete has hardened. A typical prior art tie rod is disclosed in US. Pat. No. 3,729,166 which was issued on Apr. 24, 1973 to Buyken et al. This prior art tie rod has a weakened portion or breakback 22 at which the end of the tie rod may be snapped off by applying a torque thereto. A flat-sided flangelike member 50 is attached to the tie rod near the point where it passes through an opening in the form panel. To break the end of the tie rod off, a tubular wrench 60 is inserted over the end of the tie rod until it engages the flat sides of the flangelike member 50. The tubular wrench is then turned until the tie breaks off at the weakened point 22.  
  The above-described prior art tie rod has several serious drawbacks. In the first place, a special tubular wrench is required for snapping off the ends of the tie rod. Next, wet concrete may leak out over the flatsided flangelike member 50, and after such concrete hardens, the tubular wrench may not engage the flattened sides of the flangelike member 50, and the tie rod cannot be snapped off until the leaked concrete has been laboriously chipped away. In addition, a special cover is required on the bracket which engages the head of the tie rod to prevent the tie rod from moving outwardly. Finally, the process of attaching the flatsided flangelike member 50 to the tie rod is relatively expensive, since the rod has to be bulged to provide an annularly swelled portion which fills a square hole within member 50 to couple it to the tie rod.  
 SUMMARY OF THE INVENTION In accordance with this invention, the abovenoted drawbacks are eliminated by a novel tie rod which has shoulders near the ends thereof for engaging brackets to hold the tie rod in position and which has flattened portions between the shoulders and the rod heads positioned for convenient engagement by a standard wrench to provide a torque for snapping the ends of the tie rod off at weakened regions thereof. In the preferred embodiment, the shoulders are formed by the inner boundary of the flattened portion. The tie rod is bowed in a location between each weakened region and the shoulders, with said bowed portion serving to hold a cone member in predetermined position on the tie rod to form conical openings in the concrete wall around the ends of the tie rod.  
 DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary cross-sectional view ofa concrete form showing one end of a concrete form tie rod of this invention;  
  FIG. 2 is a plan view of a bracket for holding the end of the concrete form tie rod in place while the concrete hardens;  
  FIG. 3 is a side view taken on the line 33 of FIG.  
  FIG. 4 is a top view of one end of the tie rod shown in FIG. 1; and  
  FIG. 5 is a side view of the tie rod shown in FIGS. 1 and 4.  
 DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows one end of a tie rod 10 of this invention extending through an opening 12 in a concrete form panel 14 and also extending through an opening 16 in a waler 18 adjacent to panel 14. The tie rod 10 has an opposing end (not shown) which passes through an opposing concrete form panel (not shown) and waler (not shown) on the opposite side of the concrete form. However, since the two ends are identical in form and in function, only one end will be described herein, it being understood that the description applies to both ends of the tie rod 10. Also, there is a plurality of tie rods extending between the two form panels but they are all identical and only one will be described herein.  
  The tie rod 10 has a head 20 formed on its outer end, the head 20 being engaged in a locking bracket 22 which will be described hereinafter. The tie rod 10 has spaced flattened portions 24 and 24 to anchor the rod 10 against rotation within the concrete 26 and also to provide a weakened portion at which the end of the tie may be snapped off. The outermost end of flattened portion 24&#39; has a squared corner 28 which weakens the tie rod 10 at that point so that it may be snapped off after the concrete has hardened, in response to a torque applied to the end of the tie rod 10. The flattened portion 24 keeps the main portion of the length of the tie rod 10 from rotating when the torque is applied to snap the end off. The innermost end of the flattened portion 24 has a rounded corner 30.  
  A cone member 32 is mounted on tie rod 10 adjacent to the weakened portion 28. The cone member 32 has a conically shaped portion 34 which extends through the panel 14 around tie rod 10. The conically-shaped portion 34 of cone member 32 molds a conicallyshaped opening 36 in the concrete wall which is cast within the form. After the end of the tie rod 10 has been snapped off at 28, this conically shaped opening 36 may be filled with concrete or it may be left open as a decorative feature.  
  The cone member 32 has a cylindrical portion 38 which is in the opening 12 in form panel 14, and also has four fins 40 which extend within the opening 16 in waler 18. The conical portion 34, cylindrical portion 38, and fins 40 are adjacent parts of an integral cone member 32 which is preferably made of a relatively deformable plastic material such as polyethylene, polystyrene, neoprene, or the like. A longitudinal opening 42 which has a somewhat larger diameter than tie rod 10 is formed in cone member 32 for slideably receiving the tie rod 10. Cone member 32 is slid on tie rod 10 before the head 20 is formed on the tie rod. In accordance with this invention, the tie rod 10 is formed with an outwardly bowed portion as at 44 (see FIGS. 4 and 5) so as to bind within the opening 42 to hold the cone member 32 in the proper position on tie rod 10. When the cone member 32 is slid on tie rod 10, it is forced over the bowed portion 44 to the position shown in FIG. 1, the deformable material of cone 32 allowing the larger diameter central opening 42 thereof to deform enough to accept the bowed portion 44 but not enough to prevent the bowed portion 44 from binding within the opening 42 to hold the cone member 32 in position.  
  As shown in FIG. 1, the cylindrical portion 38 of cone member 32 is slightly smaller in diameter than the opening 12 in panel 14 but not small enough to permit wet concrete to flow around it. Thus the cylindrical portion 38 acts as a plug within opening 12.  
  A bracket 22 for holding the end of tie rod 10 in position is attached to waler 18 by means of nails 46. A plan view of bracket 22 is shown in FIG. 2 and a side view is shown in FIG. 3. Referring to FIGS. 1-3, the bracket 22 includes a base plate 48 which has corner openings for receiving the nails 46 and a central opening 50 for receiving the end of tie rod 10. A slotted cam plate 52 is swingably attached to base plate 48 by a rivet 54. Cam plate 52 has an arcuate slot 56 therein (see FIG. 2) for embracing the end of tie rod 10.  
  In accordance with this invention, the end of tie rod 10 immediately inward of head 20 is flattened at 56 (see FIGS. 4 and so that the inner margin of the flattened portion provides a shoulder 58 for preventing outward movement of tie rod 10. The flattened surface 56 is conveniently located to be engaged by a wrench to apply a torque to the end of tie rod when it is desired to break the tie rod off at weakened portion 28. As shown in FIG. 1, the shoulder 58 is located to bear against the inner side 53 of cam plate 52 adjacent to the slot 57 (see FIG. 2). which slot is made narrower than the diameter of tie rod 10, but wider than the flattened portion 56 thereof.  
  Arcuately-extending inclined cam surfaces 60 (see FIGS. 2 and 3) are provided on opposite sides of the arcuate slot 57. The slot 57 and cam surfaces-60 can be moved in a circular path by swinging the cam plate 52 about the rivet 54 as indicated by the dashed lines in FIG. 2. The cam plate 52 can be moved to the position shown. where the inner surface of tie rod head bears against the cam surface 60 and the inner surface 53 of cam plate 52 bears against the shoulder 58. The engagement of cam surfaces 60 and head 20 prevent inward movement of tie rod 10 while the engagement of shoulder 58 and the inner surface 53 of cam plate 52 prevents outward movement of the tie rod 10. It should be noted that the shoulder 58 could be formed by an enlarged or swelled portion of tie rod 10 if desired. However, it is more economical to use the inner edge 58 of the flattened portion 56 as a shoulder.  
  The use of the shoulder 58 to limit outward movement of tie rod 10 is an important feature of this invention. In the past, it has been necessary to double back the cam plate 52 over the outer surface of tie rod head 20 to limit its outward movement or use a shield such as the shield 38 of U.S. Pat. No. 3,729,166. In accordance with the present invention, however, a simple flange 62 may be formed on the bottom of cam plate 52 and the necessity of doubling the flange 62 back over tie rod head 20 is eliminated.  
 The swinging movement of cam plate 52 is limited by an embossed abutment 64 on base plate 48. Abutment 64 is positioned as shown in FIGS. 2 and 3 to prevent the end of arcuate slot 56 from being driven against the flattened portion 56 of tie rod 10.  
  In use, after the concrete 26 in the form has hardened, the cam plate 52 is swung away to expose the flattened portion 56 under tie rod head 20 so that said flattened portion may be engaged by a wrench or other suitable tool. Torque may then be applied to snap off the end of tie rod 10. Referring to FIG. 2, the flattened portion 56 is exposed by swinging the cam plate 52 in the clockwise direction about rivet 54. It should be noted that the placement of flattened portion 56 on the end of tie rod 10 insures that it will be accessible even if concrete has leaked out of the form around the cylindrical portion 38 of cone member 32. Also, the easily accessible position of the flattened portion 56 has the additional advantage that it can be grasped and turned by a standard adjustable wrench, and a special tubular wrench such as used in the prior art is not required.  
 I claim:  
  1. In a snappable concrete form tie rod having a head on at least one end thereof, and having a weakened portion spaced inwardly from said head whereby the end of the tie rod may be snapped off by applying a torque thereto, and having a cone member on said tie rod between said weakened portion and said head, the improvement wherein said cone member is constructed of deformable material and nas a longitudinallyextending bore therein which is somewhat larger in diameter than said tie rod, whereby said cone member may be freely slid along said tie rod until close to assembled position, a portion of the length of said tie rod being outwardly bowed between said weakened portion and said head while maintainingf the original diameter of the tie rod, with said outwardly-bowed portion positioned within said cone portion, and the deformable material of the cone allowing the larger diameter of its bore to deform enough to accept the bowed portion of the rod but not enough to prevent the bowed portion from binding within the bore to thereby releasably hold said cone member in final assembled position on said tie rod next to the weakened portion.  
  2. The improvement defined in claim 1 wherein the length of the outwardly-bowed portion is less than the length of the bore of the cone member.  
  3. The improvement defined in claim 1 wherein the binding engagement between the bowed portion of the tie rod and the bore of the cone is the sole means for releasably holding the cone against movement on the tierod.