Abstract:
A hose clamp is provided with a pair of radially outward bent terminal ends, which are squeezable towards each other to expand the clamp. One of the terminal ends is provided with a projecting tongue that cooperates with the other terminal end to function as an interlocking assembly. Each of the terminal ends is also provided with one of a projection or depression to secure the other terminal end thereto. The interlocking assembly maintains the clamp in an expanded state, while resisting uncoupling of the terminal ends in a lateral direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 09/255,770 filed on Feb. 23, 1999 now U.S. Pat. No. 6,038,744. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates in general to hose clamps, and more specifically to self-compensating hose clamps constructed to be inherently capable of holding their expanded state without the use of a separate holding assembly. 
     BACKGROUND OF THE INVENTION 
     Various hoses are generally used in engine compartments of automotive vehicles for cooling the engine and supplying heat to the interior of the car. These hoses include those intended for use with low pressurized fluids which necessitate the use of a clamp to prevent disconnection and to maintain a fluid tight seal during use. A generally ring-shaped metal hose clamp is conventionally used so that the hose is reliably clamped by the inherent spring force designed into the construction of the clamp. It has been found desirable to provide the hose clamp at the site of assembly in a preexpanded state to facilitate its application and to increase the efficiency of the hose assembly connection process. 
     The aforementioned hose clamps were designed as an improvement over hose clamps of the type known from Hashimoto, et al., U.S. Pat. No. 4,425,682. When installing a hose clamp of the type disclosed in Hashimoto, et al., the hose clamp is first gripped and spread with a spreading tool into an expanded state while being positioned onto a fluid connection piece or the end of the hose. During the entire installation, the hose clamp must be kept spread open by means of the spreading tool. When the hose end has been pushed onto the connection piece, the expanded hose clamp is moved to its intended position by means of the spreading tool, and the spreading tool is detached from the hose clamp. The hose clamp springs back towards its original non-expanded state so as to compress about the hose thereby clamping the hose onto the connection piece in a fluid tight connection. 
     The use of a hose clamp pursuant to Hashimoto, et al., suffers from a number of disadvantages. For example, the use of such a hose clamp requires that one hand be used for manipulating the hose clamp with the spreading tool and the other hand for manipulating the hose end itself. This, plus the fact that the hose clamp can only be manipulated with a spreading tool and by applying considerable spreading force thereto, results in various installation problems and the possibility of improper connection which could result in fluid leaks and the like. 
     To this end there is known improvements to the aforementioned hose clamps which are operative for maintaining their expanded state without continuous manipulation of a spreading tool. Hose clamps of this type are known from, for example, Kimura, et al., U.S. Pat. No. 5,414,905; Oetiker, U.S. Pat. No. 5,203,809; Kawashima, et al., U.S. Pat. No. 5,185,907; Takahashi, U.S. Pat. No. 4,996,749; Muhr, U.S. Pat. No. 4,930,192; Takahashi, et al., U.S. Pat. No. 4,930,191; Kato, et al., U.S. Pat. No. 4,858,279; and Muhr, U.S. Pat. No. 4,773,129. 
     By way of example, Kimura, et al. discloses a self-locking hose clamp formed from a clamp body comprising a leaf spring arranged in the form of an annular band. The ends of the clamp body are bent relative to the main portion of the band to serve as grip strips. An engagement claw extends from one of the grip strips so as to be engageable with the other of the grip strips to hold the clamp body in a spread-diameter state in which the ends of the clamp body are close to each other. The engagement claw includes a claw portion projecting in an axially direction with respect to the annular band and a guide extending obliquely to the axial direction. The guide is operative for guiding the grip strips axially to guide the engagement claw into engagement with the opposing grip strip when the grip strips are brought towards each other in a circumferential direction to maintain the hose clamp in a spread-diameter state. 
     One of the deficiencies of the hose clamp pursuant to Kimura, et al. is the possible slippage of the engagement claw from the opposing grip strip, and in particular, in a lateral direction. In this event, the hose clamp due to the stored energy can become a dangerous projectile. Another deficiency of Kimura, et al. is the notable absence of a positive stop member. In this regard, as the grip strip engages the guide at the end of the engagement claw, this allows the grip strips to be brought closer together thereby further expanding the annular band. As a consequence, there is the possibility of over expanding the hose clamp thereby inducing adverse mechanical stresses that can affect the integrity of the hose clamp during use. This deficiency has been overcome by constructing a hose clamp having a stop member as known from European Patent Application EP O713993. 
     The European application discloses a hose clamp formed from an annular band having a notch that enables the formation of a bent up tab to provide a stop member. Although the stop member is operative to prevent over expansion of the hose clamp, the construction by including a notch to form the tab results in a number of disadvantages. For example, the presence of the notch affects the integrity or mechanical strength of the annular band. Further, the formation of the tab requires an additional forming step of bending thereby adding additional tooling and manufacturing process operations. Still further, to the extent there is the desire to manufacture a hose clamp which does not include a self-locking feature, such as disclosed in the aforementioned Hashimoto, et al., the tooling requirements and change over time can adversely impact on the manufacturing efficiency and versatility. 
     The other aforementioned known hose clamps that provide a self-locking feature also suffer from disadvantages. For example, they may include complicated construction features that require advanced tooling resulting in further manufacturing costs, the use of separate removable locking elements and the like. In the case of a removable locking element, this construction is considered dangerous, as the locking element often becomes a projectile when removed due to the spring force created by the hose clamp. Thus, it can be appreciated that there is still the need for further improvements in hose clamps which provide a self-locking feature. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a hose clamp that includes a self-locking feature which provides improved locking when in its expanded condition. 
     Another object of the present invention is to provide a hose clamp that is of simple construction. 
     Another object of the present invention is to provide a hose clamp that preserves the integrity of the annular band so as to maintain its mechanical strength. 
     In accordance with one embodiment of the present invention there is described a hose clamp comprising a clamp body having a longitudinal axis formed into an annular configuration having a main section and first and second terminal ends formed outwardly relative to the main section, the first terminal end formed between a pair of spaced apart side edges having a first notch opening along one side edge thereof, a tongue at the second terminal end projecting in a direction toward the first terminal end formed between a pair of spaced apart side edges having a second notch opening along one side thereof in an opposite direction to the first notch, a portion of the first terminal end adjacent the first notch provided with one of a depression or a projection releasably engageable with a portion of the tongue, the first and second notches being engageable with each other to releasably hold the clamp body in an expanded state and being disengageable with each other to release the clamp body from the expanded state upon lateral displacement of the tongue relative to the first terminal end wherein the one of the depression or the projection is disengaged from the portion of the tongue. 
     In accordance with another embodiment of the present invention there is described a hose clamp comprising a clamp body having a longitudinal axis formed into an annular configuration having a main section and first and second terminal ends, the first and second terminal ends being bent outwardly relative to the main section, the first terminal end formed between a pair of spaced apart side edges having a U-shaped first notch opening along one side edge thereof, a tongue at the second terminal end being bent relative thereto in a direction toward the first terminal end, the tongue formed between a pair of spaced apart side edges having a U-shaped second notch opening along one side thereof in an opposite direction to the first notch, the first and second notches arranged on opposite sides of the longitudinal axis, a portion of the first terminal end adjacent the first notch provided with one of a depression or a projection releasably engageable with a portion of the tongue, the first and second notches being engageable with each other to releasably hold the clamp body in an expanded state upon twisting the tongue past the first terminal end and being disengageable with each other to release the clamp body from the expanded state upon lateral twisting of the tongue relative to the first terminal end wherein the one of the depression or the projection is disengaged from the portion of the tongue. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above description, as well as further objects, features and advantages of the present invention will be more fully understood with reference to the following detailed description of a hose clamp, when taken in conjunction with the accompanying drawings, wherein: 
     FIG. 1 is a top plan view of a band stamped to provide the features of a hose clamp constructed in accordance with the present invention prior to forming into an annular configuration; 
     FIG. 2 is a perspective view of a hose clamp constructed from the band shown in FIG. 1 after forming into an annular configuration for use in a variety of hose clamping applications; 
     FIG. 3 is a top plan view of the hose clamp in its annular configuration as shown at FIG. 2; 
     FIG. 4 is a perspective view of the hose clamp in a self-locking expanded state wherein the annular band has been expanded from its contracted state as shown in FIG. 3; 
     FIG. 5 is a top plan view of the hose clamp compressed about a hose to form a fluid tight seal with a connection piece to which the hose is attached; 
     FIG. 6 is a top plan view of the hose clamp in a self-locking expanded state adhered to a hose for clamping thereto; 
     FIG. 7 is a side view of the interconnection between the first and second terminal ends having a locking element in accordance with another embodiment of the present invention; 
     FIG. 8 is a side view of the interconnection between the first and second terminal ends having a locking element in accordance with another embodiment of the present invention; 
     FIG. 9. is a front view of the first terminal end provided with a circular shaped depression as the locking element; 
     FIG. 10 is a front view of the first terminal end provided with an oval shaped depression as the locking element; and 
     FIG. 11 is a front view of the first terminal end provided with an polygonal shaped depression as the locking element. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In describing the preferred embodiments of the subject matter illustrated and to be described with respect to the drawings, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and is to be understood that each specific term includes all technical equivalence which operate in a similar manner to accomplish a similar purpose. 
     Referring now to the drawings, wherein like reference symbols represent like elements, there is shown in FIG. 1 an elongated band 100 which has been configured to form a hose clamp in accordance with one embodiment of the present invention. The band 100 is generally stamped using progressive tooling from a sheet of metal having a uniform thickness. The band 100 is formed from materials such as spring steel that provides inherent spring-like properties. By way of example, the band 100 can be formed from carbon steel, 6150 chrome-vanadium alloy and the like. It is therefore to be understood that other metals and metal alloys that possess spring-like properties may be used in the construction of the hose clamp in accordance with the present invention. 
     The band 100 is formed to include a main section 102 having a longitudinal axis 103, a first terminal end 104 and a second terminal end 106. The main section 102 includes a straight portion 108 formed between a pair of parallel spaced apart side edges 110, 112 and a tapered portion 114 formed between a pair of spaced apart tapered side edges 116, 118. The tapered portion 114 is formed without any openings, while the straight portion 108 is formed with a plurality of openings 120, 122, 124 that may have a variety of shapes. For example, openings 120, 122 are illustrated as having a triangular shape, while opening 124 has a narrow elongated rectangular or slightly trapezoidal shape. The openings 120, 122, 124 provide a uniform clamping force over the entire circumference of a hose when it is clamped by means of the hose clamp. In addition, opening 124 is sized and shaped as a guide to permit movement of the tapered portion 114 of the band 100 as the band is regularly expanded and contracted when formed into an annular band. In this regard, it is to be understood that the size, shape and locations of the openings 120, 122, 124 are based upon principals well known in the art of hose clamp design, the details of which are therefore known to those skilled in the art. 
     The first terminal end 104 of the band 100 is generally defined between the location identified by dashed line 126 and a terminal edge 128 which is in the nature of a flat face, as well as between the side edges 116, 118. It will be understood from a description of the operation of the hose clamp that the terminal edge 128 may be other than a flat face if so desired. A first notch 130 is formed in the terminal end 104 adjacent terminal edge 128 having its opening along side edge 118. The notch 130, in accordance with one embodiment, is illustrated as being generally rectangular or U-shaped. It is to be understood that other shapes of the notch 130 may be formed in the terminal end 104 as will be readily apparent from a further description as to the function of the notch 130. Briefly, the notch 130 will function in a cooperative manner so as to maintain the hose clamp in a releasably self-locked expanded state. 
     The second terminal end 106 is formed from the main section 102 of band 100 from a location generally beginning at dashed line 132 extending to a terminal edge 134. It is noted that the width of the second terminal end 106 is wider than the width of the first terminal end 104. This construction allows the tapered portion 114 to be received within opening 124 when the band 100 is formed into an annular configuration as shown in FIG. 2. 
     The terminal edge 134 of the second terminal end 106 is defined by an end member 136 from which there extends into the opening 124 a tongue 138. The tongue 138 is defined between spaced apart side edges 139, 141 having a longitudinal axis 143. As shown, the longitudinal axis 143 of the tongue 138 is arranged in general alignment with the longitudinal axis 103 of the band 100. The tongue 138 is provided with a terminal edge 140 which is generally defined by a flat face arranged transverse to the longitudinal axes 103, 143 of the band 100 and tongue. By virtue of this construction, the terminal edge 140 will function as a stop member as to be described hereinafter. 
     A second notch 142 is formed in the tongue 138 adjacent the terminal edge 140 opening in a direction toward side edge 141 of the tongue or side edge 110 of the band 100. It is therefore to be noted that the first and second notches 130, 142 open in opposite directions, that is, towards opposing side edges 112, 110, respectively, of the band 100. The second notch 142 may be formed as a rectangular or U-shaped notch, as well as other shapes as noted with respect to the first notch 130. Preferably, the first and second notches 130, 142 will have the same shape, for example, rectangular or U-shaped. 
     The band 100 and the features as thus far described may be formed using progressive tooling in an automated stamping apparatus from suitable metal sheet stock. The resulting band 100 will have the configuration as thus far described with respect to FIG. 1. The band 100 is configured into an annular configuration to form a hose clamp 144 as shown in FIGS. 2 and 3. During the forming process, the band 100 is formed into its circular shape with the tapered portion 114 extending through opening 124. The first terminal end 104 is bent radially outward about dashed line 126, while the second terminal end 106 is bent radially outward about dashed line 132. As best shown in FIG. 3, the first and second terminal ends 104, 106 are generally arranged along a radius 146 of the clamp 144, although other orientations are contemplated, such as at an angle on either side of the radius 146. As shown, the first and second terminal ends 140, 146 are arranged in spaced apart opposing relationship extending outwardly from the band 100. 
     Tongue 138 is bent upwardly about dashed line 148, see FIG. 1, in a direction extending toward the first terminal end 104. The tongue 138 is arranged at an angle of approximately 90° to the second terminal end 106, although other angles of a greater or less degree are also contemplated. The hose clamp 144 forms a circular opening 150 formed by the band 100. The opening 150, depending upon the overall length of the band 100, can be formed into a variety of sizes so as to accommodate hoses of an equal variety of sizes. Generally, the size of the opening 150 will be less than the outside diameter of the hose to be clamped. 
     There will now be described the use of the hose clamp 144 in accordance with one embodiment of the present invention. As thus far described, the hose clamp 144 is constructed to be releasably self-locking in an expanded state wherein the size of the opening 150 is increased from its manufactured state. With reference to FIGS. 4 through 6, a tool (not shown) such as a pair of pliers is used for engaging the first and second terminal ends 104, 106. By means of the tool, the first and second terminal ends 104, 106 are squeezed together along longitudinal axis 103 thereby expanding the size of the opening 150. Overexpansion of the hose clamp 144 is prevented by the terminal edge 140 of the tongue 138 acting as a stop member. In this regard, the terminal edge 140 of the tongue 138 is arranged in alignment with a solid portion 152 (see FIG. 1) of the first terminal end 104 adjacent the first notch 130. The engagement of the terminal edge 140 with the solid portion 152 will prevent inadvertent further expansion of the hose clamp 144 beyond its intended design limits which might otherwise affect the mechanical integrity of the clamp during use. It should be appreciated that the tongue 138 by virtue of its stop function will prevent an operator from expanding the clamp 144 whereby the first and second terminal ends 104, 106 engage one another in a condition which over expands the band 100 and potentially causes mechanical failure. 
     During the expansion of the band 100, the first and second terminal ends 104, 106 are laterally displaced slightly from each other such as by twisting. This lateral displacement allows the terminal edge 140 of the tongue 138 to bypass the solid portion 152 so that the first and second notches 130, 142 can be engaged with each other thereby locking the hose clamp 144 in an expanded state as shown in FIG. 4. The slight additional expansion of the band 100 to affect interlocking of tongue 138 with the first terminal end 104 will not affect the mechanical integrity of the band 100. 
     In its expanded state, the hose clamp 144 may be slipped over a hose 154 such as shown in FIG. 5. The hose is subsequently forced over an appropriate connection piece (not shown) to which fluid connection is desired. A fluid tight connection is obtained by releasing the clamp 144 so that it returns towards its initial unexpanded condition thereby providing a uniform compressive force circumferentially about the hose 154 by means of the band 100. This is accomplished using a suitable tool (not shown) such as a screw driver or the like to once again laterally displace such as by twisting the first and second terminal ends 104, 106 thereby disengaging the first and second notches 130, 142 which are respectively formed in the first terminal end 104 and tongue 138. The hose 154 under compression of the hose clamp 144 is illustrated in FIG. 5. If desired, the hose clamp 144 may be removed for replacement of the hose 154 by reversing the process of squeezing the first and second terminal ends 104, 106 towards each other using any suitable tool such as a pair of pliers and the like. 
     In accordance with another embodiment, it is known in the industry to glue or otherwise adhere a hose clamp 144 in its locked expanded state onto a hose 154 such as shown in FIG. 6. It is known to perform this operation at the site of the hose manufacturer such that a hose and clamp assembly is shipped to the end user in the condition as shown. At the site of installation, an operator will force the hose of the hose clamp assembly over the connection piece to which fluid connection is desired. Once installed, the operator using a suitable tool will release the hose clamp 144 from its locked expanded state to return to its state as shown in FIG. 5 thereby applying a fluid tight compressive force to the hose 154. The hose clamp 144 may be removed for replacement of the hose 154 in a manner as previously described. 
     FIGS. 7-11 illustrate different embodiments for providing for a more secure engagement between the first and second terminal ends by providing a locking element. As shown in FIG. 7, the second terminal end 140 is provided with a projection 160 that extends downward from surface 161 into the second notch 142. The projection 160 could also extend from the surface 163, in addition to or as an alternative. The projection 160 can be provided with a square, rounded or polygonal shape that may correspond to the shape of a depression 162 on the opposing first terminal end 128. When the first terminal end 128 and the second terminal end 140 of the tongue 138 engage each other, the projection 160 engages the depression 162 to prevent the second terminal end 140 from slipping out of engagement with the first terminal end, and specifically, in a lateral direction. While the use of a projection 160 on the second terminal end to engage a depression 162 on the first terminal end, is one preferred embodiment, no projection is required on the second terminal end 140, since the depression 162 can by itself provide a more secure means of engaging the second terminal end. In this regard, the tip 165 of the tongue 138 will tend to seat itself in the depression 162 as it tends to form a projection. 
     In another embodiment as shown in FIG. 8, the first terminal end 128 is provided with a projection 164 located adjacent the first notch 130 to engage a depression 166 in surface 161 of the second terminal end 140. A similar depression may be provided in surface 163. When the first terminal end 128 and the second terminal end 140 of the tongue 138 engage each other, the projection 164 engages the depression 166 to prevent the second terminal end 140 and the first terminal end 128 from slipping out of engagement with each other. The shape of the depression 166 on the second terminal end 140 can be shaped in the same way as the depression 162 on the first terminal end 128 described above. Further, the shape of the projection 164 on the first terminal end 128 can be selected to correspond to the shape of depression 166 on the second terminal end 140. 
     FIGS. 9-11 illustrate several different depression designs, each of which provide an improved means of securing the terminal ends. As shown in FIG. 9, a circular-shaped depression 170 is provided at the solid portion 152 of the terminal end 128 adjacent to the first notch 130. As shown in FIG. 10, an oval-shaped depression 172 is provided at the solid portion 152 of the first terminal end 128 adjacent to the first notch 130. As shown in FIG. 11, a V-shaped depression 174 is provided at the solid portion 152 of the terminal end 128 adjacent to the first notch 130. While FIG. 11 shows a V-shaped depression, any type of polygonal-shaped depression can be used with the current invention. 
     It is to be understood that the shape of the projections 160, 164 may be of various geometries, such as square, round, oval, polygonal, etc., as well as being of varying lengths. Similarly, the shape of the depressions 162, 166, 170, 172, 174 may be equally varied as noted hereinabove. In this regard, the depressions 162, 166, 170, 172 function in the nature of a seat for receiving a portion of the projection 160, 164 to enhance their locked relationship. 
     Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.