U-bolt clamps are used for joining together sections of tubing at a connection wherein one piece of tubing is telescoped within another. U-bolt clamps are commonly used to join various components of internal combustion engine exhaust systems, such as exhaust pipes, tail pipes, mufflers, etc. In order to secure the two pieces of tubing relative to one another, the curved portion of the U-bolt and the curved portion of the saddle are placed in contact with the tubing in the area of overlap. Thereafter the saddle is tightened down onto the U-bolt so that the two layers of overlapping tubing deform or crimp into one another. A large amount of force is required to cause the crimping and, hence, both the U-bolt and saddle must have sufficient strength to withstand such forces.

The U-bolts themselves generally have sufficient strength to withstand the forces required to crimp tubing being joined. However, problems have arisen with the saddle portion of the assemblies. Some of the prior art saddle assemblies have tended to twist when force suffi¬ cient to crimp tubing has been applied. Prior art U-bolt clamp assemblies have attempted to strengthen saddles in a number of ways. One method has been to double the thick¬ ness of the web area, either in full or partially. An- other method has been to use flanges extending perpen¬ dicularly from the surface of the web sections. The construction of such prior art saddles has generally been complicated due to the requirement of welding of the various components. Examples of various- prior art clamps are found in United States Patent Nos. 3,137,053 to Osborn et al., issued June 16, 1964; 3,192,593 to Osborn et al., issued July 6, 1965; 3,605,214 to Spotts et al., issued

September 20, 1971; 3,729,782 to Downing, issued May 1 1973; 3,772,745 to Dowling et al., issued November 20 1973; 3,879,815 to Dowling et al., issued April 29, 1975 3,919,747 to Offterdinger, issued November 18, 1975 4,040,152 to Gilgallon, issued August 9, 1977; an 4,056,869 to Eisma, Jr., issued November 8, 1977.

In addition to the strength requirement, sim plicity of construction is another important criterion fo the saddles. While the prior art saddles may appear to b simple in construction, the requirement of welds can driv up the per unit cost of the saddles.

Summary of the Invention The present invention relates to a saddle for U-bolt clamp assembly. The saddle is comprised of single sheet metal member. The sheet metal member i folded to form a two-layer web portion and a pair o tubular portions. Each tubular portion is adapted t receive a leg of a U-shaped bolt- Each tubular portion i formed of two layers of said sheet metal around a majo portion of the circumference of each tubular portion.

Each tubular portion is thus formed of an inne layer and an outer layer of the sheet metal. The inne layer extends around substantially a 360° circumferentia extent, while the outer layer extends around at least 180° circumferential extent. In one embodiment, the oute layers of the two tubular sections are both bent in th same rotative direction. The rotative direction is chose such that it is in the same rotative direction in whic nuts on the U-bolt will rotate when they are tightene down. In this manner, the outer layers will not tend t unwrap when the clamp is tightened down onto tubes to b joined.

The web portion of the saddle is two-layere over its entire area and the tubular portions ar double-layered over a major portion of their circumfer ence. The double layering of the web portion increase the strength of the web portion. The double layering o the tubular portion provides increased bearing surface fo the nuts to tighten down upon and also secures the saddl

in its folded condition without the use of welds. Since no welds are utilized to form the saddle, the method of construction is simplified.

Various advantages and features of novelty which characterize the invention are pointed out with particu¬ larity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the inven¬ tion, its advantages, and objects attained by its use, reference should be had to the drawings which form a further part hereof, and to the accompanying descriptive matter, in which there is illustrated and described sever¬ al embodiments of the invention.

Brief Description of the Drawings FIGURE 1 is a plan view of a strip of sheet metal material wherein a plurality of blanks have been stamped for producing saddles in accordance with the present invention;

FIGURE 2 is a plan view of a single piece of sheet metal material from which a clamp in accordance with the present invention is made;

FIGURES 3-5 are perspective views illustrating steps of a method for making a first embodiment of a saddle in accordance with the present invention;

FIGURE 6 is a front elevational view of a saddle and U-bolt forming a U-bolt assembly in accordance with the present invention;

FIGURE 7 is a sectional view taken along line 7-7 of Figure 6;

FIGURES 8-11 are perspective views illustrating steps of a method for making a second embodiment of a saddle in accordance with the present invention;

FIGURE 12 is a plan view of a single piece of sheet metal material configured to form a third embodiment of a saddle in accordance with the present invention; FIGURES 13-16 are perspective views illustrating steps of a method for making a third embodiment of a saddle in accordance with the present invention;

-^0REATT

OMPI

FIGURE 17 is a sectional view illustrating U-bolt assembly securing together two tubular members;

FIGURE 18 is an end view of the embodiment o the saddle shown in Figure 11; and FIGURE 19 is an end view of the embodiment o the saddle shown in Figure 16.

Detailed Description of the Invention

Referring to the drawings in detail, wherei like numerals indicate like elements, there is shown i FIGURE 6 a U-bolt clamp assembly in accordance with th present invention generally designated as 10. The U-bol clamp assembly 10 is comprised of a U-bolt 12, a saddl

14, and a pair of nuts 16. The U-bolt 12 has a pair o legs 18 generally parallel to one another which are inter connected by a curvilinear section 20. Each leg 18 has threaded end 22 onto which the nuts 16 are threaded.

The saddle 14 has a two-layered web portion 2 and a pair of tubular portions 26, 28. The web portio 24 is double- or two-layered through its entire area Each tubular portion 26, 28 has an inner layer 30 and a outer layer 32. The inner layer 30 has a circumferentia extent of substantially 360° and thus forms a complet tube through which a leg 18 can pass. The outer layer 3 is bent to form a partial tube and extends around a cir cumferential extent of at least 180°.

The method of forming the saddle 14 can best b understood by referring to FIGURES 1-5. A strip or por tion of a roll of sheet metal material 34 is shown i FIGURE 1. A plurality of single-piece sheet metal member 36 are cut or formed from the strip 34. A single membe 36 is shown in FIGURE 2. The sheet metal members 36 ca be cut or stamped from the strip 34 in any conventiona manner.

Each sheet metal member 36 has a central sectio 38, an end section 40 on one side of the central sectio 38, and an end section 42 on the other side of the cen tral section 38. The sheet metal member 36 also has pair of opposing side edges 44, 46. A slit or cut-out 4

extends inwardly from the side edge 44 toward the central section 48 and a slit 50 extends inwardly from the side edge 46 toward the central section 48. A fold line 52 extends between and is aligned with the slits 48, 50. The slits 48, 50 and the line 52 divide the member 36 gener¬ ally in half into a first portion and a second portion. That is, the central section 38 is divided into a first portion 54 and a second portion 56; the end section 40 is divided into a first portion 58 and a second portion 60; and the end section 42 is divided into a first portion 62 and a second portion 64. The second portions 60, 64 have outer trimmed edges 45. The first and second portions 54, 56 of the central section 38 each have an outer curvi¬ linear edge 66. When the member 36 is folded into its final form, the curvilinear edges 66 form the lip of the web portion 24.

The method of forming the saddle 14 is best illustrated in FIGURES 3-5. The portions 60, 64 of the end sections 40, 42 are bent upwardly and around in oppo- site rotative directions to form the tubes of the inner layers 30. The portions 58, 62 of the end sections 40, 42 are bent in part to form curved receiving areas for the inner layers 30. See FIGURE 3.

The first and second portions of the member 36 are thereafter folded along the fold line 52 as shown by arrow 68 in FIGURE 3. As is shown in FIGURE 4, the first and second portions are folded into one another so that the inner layer 30 is received within the curved areas of portions 58, 62 and so that a two-layered web portion 24 is formed. The diameter of the inner surface of the portions 58, 62 which form the curved receiving areas, is slightly greater than the diameter of the outer surface of the inner layers 30. In this manner, when the member 36 is folded, the inner layers 30 fit flush within the curved areas of the portions 58, 62.

Finally, the remaining unbent areas of the portions 58, 62 are bent around the inner layers 30 to form the outer layers 32. Since the outer layer 32 wraps

OMPI

around the inner layer 30 of each tubular portion 26, 2 no welds are required to secure the saddle 14 in i folded form. As is best seen in FIGURE 5, the two inn layers 30 are bent in opposite rotative directions fr one another and the two outer layers 32 are also bent opposite rotative directions from one another. The inn and outer layers 30, 32 of the tubular portion 26 a bent in opposite rotative directions to one another, are the layers 30, 32 of the tubular portion 28. There is illustrated in FIGURE 11 a seco embodiment of a saddle in accordance with the prese invention designated generally as 70. The method forming or making the saddle 70 is illustrated in FIGUR 8-11. Portions of the saddle 70 which are similar portions of the saddle 14 will be indicated by like prim numbers.

The saddle 70 is formed from a single-pie sheet metal member 36'. The member 36' has the sa configuration as member 36. The first portions 60', 6 are bent downwardly and the second portions 58', 62' a bent upwardly. See FIGURE 8. Thereafter, the first po tions 60', 64' are bent to form a closed tube of substa tially 360° circumferential extent. The first portio 60', 64' thus form the inner layers 30'. Thereafter, t first and second portions of the member 36' are fold about the line 52' in the direction of arrow 68' . S FIGURE 8.

The diameter of the inner surface of the po tions 58', 62' , which form the curved receiving areas, slightly greater than the diameter of the outer surface the inner layers 30'. In this manner, when the member 3 is folded, the inner layers 30' fit flush within t curved areas of the portions 58' , 62' . See FIGURE 10. T second portions 58' , 62' are thereafter bent around t inner layers 30' to complete the outer layers 32'. S FIGURE 11. In the saddle 70, the inner and outer laye 30', 32' of the tubular portion 26' are both in the sa rotative direction. The inner and outer layers 30', 3

of the tubular portion 28'- are both in the same rotative direction, which is opposite from the rotative direction of the inner and outer layers 30', 32' of the tubular portion 26' . There is illustrated in FIGURE 16 a third em¬ bodiment of a saddle in accordance with the present inven¬ tion designated generally as 72. The method of forming or making the saddle 72 is illustrated in FIGURES 13-16. Portions of the saddle 72 which are similar to portions of the saddle 14 will be indicated by like double-primed numbers.

The saddle 72 shown in FIGURE 16 is formed from a single-piece sheet metal member 74. The member 74 is similar to the members 36, 36' in all aspects except for the location of trimmed edges 76. In the member 74, the trimmed edges 76 are on opposite portions of the member 74, while in the members 36, 36' the trimmed edges 45 are on the same portion of the member 36, 36' .

The first portions 58", 62" and the second portions 60", 64" are all bent upwardly. See FIGURE 13. The first portion 58" and the second portion 64", which are on the opposite sides of fold line 52" and diagonally across from one another, are both thereafter bent com¬ pletely around to form a closed tube having a circumferen- tial extent of substantially 360°. Inner layers 30" are thus formed. See FIGURE 14. The member 74 is thereafter folded along fold line 52" in the direction of arrow 68".

The diameter of the inner surface of the por¬ tions 60", 62", which form the curved receiving areas, is slightly greater than the diameter of the outer surface of the inner layers 30". In this manner, when the member 74 is folded, the inner layers 30" fit flush within the curved areas of the portions 60", 62". See FIGURE 15. The portions 60", 62" thereafter are bent completely around the inner layers 30" to form the outer layers 32". See FIGURE 16. The direction of rotation of both the outer layers 32" is the same and is chosen such that the rota¬ tive direction is the same as the rotative direction of

the nuts 16 to be threaded on the U-bolt legs 18 which a received in the tubular portions 26", 28". Thus, when t nuts are tightened down, the nuts tend to hold the out layers 32" in position, rather than to unwrap the out layers 32". The inner layers 30" are also bent in o rotative direction. However, the rotative direction which the inner layers 30" are bent is opposite from t rotative direction in which the outer layers 32" are bent. The use of a U-bolt clamp assembly 10 is illu trated in FIGURE 17. A first tube 80 has an end 82 whi is received within an end 84 of a second tube 86. U-bolt 12 and a saddle 14 are placed about an overlappi area 86 of the ends 82, 84. The nuts 16 are then thread onto the legs 18 of the U-bolt 12 until the lip of t saddle 14 and the curvilinear section 20 of the U-bolt are tightened down upon the ends 82, 84 with a sufficie degree to cause a crimp joint 88 within the area 86. Bo the lip of the saddle and the curvilinear section 20 a preferably arcs of circles and thus mate with the out circumference of cylindrical tubes.

Numerous characteristics and advantages of t invention have been set forth in the foregoing descri tion, together with details of the structure and functi of the invention, and the novel features thereof a pointed out in the appended claims. The disclosure, ho ever, is illustrative only, and changes may be made detail, especially in matters of shape, size, and arrang ment of parts, within the principle of the invention, the full extent indicated by the broad general meaning the terms in which the appended claims are expressed.

U/