Overcenter locking hose clamp
BACKGROUND OF THE INVENTION 
     Various forms of hose clamps heretofor have been provided for retaining a hose end in position over a tubular nipple or the like. Most previous forms of hose clamps include positive displacement clamp structure which must be tightened in order to secure the clamp over the associated hose end. However, hoses are conventionally constructed of resilient material and hose ends with which positive displacement hose clamps are engaged tend to deform with the result that unless a positive displacement hose clamp is substantially over tightened the reduction in the outer circumference of the associated hose end portions with which the clamp is engaged as a result of deformation of the hose material can cause the clamped connection to become loose over a period of time. In addition, when positive displacement hose clamps are used the deformation of the associated hose end in many instances requires the necessity of a new hose clamp and/or a new hose section if a hose end and associated nipple connection is to be loosened for repair or inspection purposes. 
     Accordingly, a need exists for an improved form of hose clamp to be used in other than high pressure hose applications and constructed in a manner whereby deformation of the associated hose end by continued compressive forces thereon by the hose clamp may be automatically compensated for. 
     In addition, a need exists for an improved form of hose clamp which will minimize deformation of an associated hose end and thereby enable, in substantially all instances where a hose and nipple connection is to be released for inspection or maintenance purposes, enabling reuse of the hose clamp and the hose end over a period of repeated connection release and restablishment operations. 
     Examples of previously known forms of clamps including some of the general structural and operational features of the instant invention are disclosed in U.S. Pat. Nos. 867,518, 2,835,015, 2,986,325 and 3,441,987. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The clamp of the instant invention is in the form of a rigid but somewhat flexive annular member having overlapped ends. The overlapped ends include channel member end sections telescopingly engaged with each other and one of the channel shaped ends pivotally supports an overcenter swingable lever therefrom while the other channel member includes anchor structure. An elongated stiff expansion spring has one end anchored relative to the anchor structure and the other end anchored relative to the lever at a point spaced therealong from its axis of oscillation relative to the corresponding channel member end. In addition, the lever and corresponding channel member end include coacting structure whereby the axis of oscillation relative to the corresponding channel member end may be longitudinally shifted along the latter, thereby adapting the clamp to be used in conjunction with hoses of different sizes. 
     The main object of this invention is to provide an improved hose clamp which does not include positive displacement clamping means, but instead includes resilient clamping means thereby enabling the clamp to be used in conjunction with a hose end constructed of a material which will deform under clamping pressures. 
     Another object of this invention is to provide an improved form of hose clamp which may be quickly adjusted for use in conjunction with hoses of different sizes. 
     Still another important object of this invention is to provide a hose clamp which may be primarily constructed of high strength plastic materials as well as various metals. 
     Yet another object of this invention is to provide an improved hose clamp which will be capable of performing a hose clamping operation without exerting excessive clamping pressures on the associated hose end. 
     A final object to be specifically enumerated herein is to provide an improved form of hose clamp in accordance with the preceding objects and which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long lasting and relatively trouble free in operation. 
     These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a hose clamp constructed in accordance with the present invention; 
     FIG. 2 is a sectional view taken substantially upon the plane indicated by the section line 2--2 of FIG. 1; 
     FIG. 3 is an enlarged fragmentary sectional view taken substantially upon the plane indicated by the section line 3--3 of FIG. 2; and 
     FIG. 4 is a fragmentary sectional view taken substantially upon the plane indicated by the section line 4--4 of FIG. 2. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     Referring now more specifically to the drawings the numeral 10 generally designates the hose clamp of the instant invention. The clamp 10 includes an elongated arcuate band type strip member 12 having overlapped opposite ends 14 and 16 and the end 14 includes longitudinally extending opposite side flanges 18 wherein the end 14 is in the form of a channel member and the end 16 includes longitudinally extending opposite side flanges 20 wherein the end 16 also is in the form of a channel member. 
     The end of the channel member defined by the flanges 20 remote from the free end of the end 16 includes a transverse wall 22 centrally apertured as at 24 and the wall 22 and aperture 24 comprise anchor structure to be hereinafter more fully set forth. 
     The flanges 18 of the end 14 include longitudinally spaced generally trapezoidal notches 26 formed therein. The notches 26 and each flange 18 are registered with corresponding notches 26 formed in the other flange 18 and an elongated arcuate lever 28 is provided including first and second end portions 30 and 32. The end portion 32 includes a pair of oppositely laterally outwardly projecting ears 34 which are selectively receivable in a pair of corresponding notches 26 formed in the flanges 18. The lever 28 includes a laterally struck tongue portion 36 to which one end of a stiff expansion spring 38 is releasably anchored and the other end of the expansion spring 38 is releasably anchored relative to the anchor structure defined by the wall 22 having the aperture 24 formed therethrough. The lever 28 is swingable between the phantom and solid line positions thereof illustrated in FIG. 2 and during swinging of the lever 28 from the phantom line position to the solid line position the lever 28 is swung past a center position. Accordingly, when the lever 28 is in the solid line position illustrated in FIG. 2 of the drawings and the clamp 10 is clamped about a hose such as the hose 40 illustrated in phantom lines, the expansion spring 38 not only supplies the clamping action of the clamp 10 about the hose 40 but also serves to maintain the lever 28 in the solid line position thereof. 
     Inasmuch as the flanges 18 include longitudinally spaced notches 26, the end portion 32 of the lever 28 may have its oppositely and outwardly directed ears 34 engaged in selected pairs of the notches 26 in order to adapt the clamp 10 for clamping engagement about hoses of different diameters. 
     The channel shaped end 16 is telescoped within the channel shaped end 14 and thereby prevents relative lateral displacement of the ends 14 and 16. In addition, inasmuch as the clamping action applied by the clamp 10 is effected by the expansion spring 38, an adequate fluid tight seal in low pressure situations may be maintained by the clamp 10 between the hose 40 and an associated tubular nipple without excessive clamping action on the hose 40. As the hose end being clamped by the clamp 10 deforms slightly due to the clamping action thereon, the spring 38 will automatically maintain the clamp 10 properly clamped engaged with the hose end 40. Therefore, it is not necessary for the clamp assembly 10 to be over tightened in order to compensate for deformation of the portion of the hose 40 with which the clamp 10 is clampingly engaged. 
     The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.