"Ring Clamp for Securing a Hose to a Barbed Fitting'
BACKGROUND OF THE INVENTION The present invention relates to a clamp for securing a hose to a barbed fitting. Clamps to hold flexible hoses on a barbed fitting have typically used an interference fit. The terms hose and fitting as used in this application may apply to any type of fluid lines. Once these clamps have been subjected to heating and cooling cycles, the clamp dimension may sometimes change, and the connection between the fitting and the hose weakens. For fluid lines in a vehicle, the clamp may be exposed to a temperature range of -40°F to 300°F. These extreme temperatures have caused prior art clamps to weaken. To address the problem, metal hose clamps have been utilized which are crimped onto the hose. These clamps may' sometimes apply undesirable stress to the hose.
SUMMARY OF THE INVENTION One embodiment of the present invention provides a polymeric ring clamp which press fits the hose against the fitting barbs. The ring clamp is formed of a material with a higher resistance to temperature extremes than the hose. That is, the ring clamp preferably has a lower coefficient of thermal expansion than the flexible hose. Most preferably, the ring clamp is resistance to any significant expansion or contraction over a temperature range of -40°F to 300°F. A ring clamp made according to this teaching in a vehicle exerts a substantially continuous hoop stress holding the hose on the fitting during typically heating and cooling cycles. Preferably, the ring clamp may have a radially inwardly extending member which squeezes the hose between adjacent barbs on the fitting. In a most preferred embodiment of the present invention, the radially inwardly extending members may be ramped to facilitate the sliding movement of the ring clamp over the barbs to secure the hose to the fitting.
In another aspect of the present invention, a method of securing a flexible hose to a barbed fitting is disclosed wherein a generally cylindrical ring clamp is formed of a material that is more resistant to thermal expansion or contraction than the flexible hose. The ring clamp has an inner peripheral surface which defines an inner diameter that is less than the outer diameter of the flexible hose received on the barbs. The ring clamp is slid over the hose and fitting, such that its inner peripheral surface squeezes the hose radially inwardly at the barbs to secure the hose to the fitting.
These and other objects of the present invention can be best understood from the following specification and drawings, of which following is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of a first embodiment fluid connector. Figure 2 is a cross-sectional view of a second embodiment fluid connector.
Figure 3 is a cross-sectional view of a third embodiment fluid connector.
Figure 4 is a cross-sectional view of a ring clamp according to a fourth embodiment of the present invention.
Figure 5 is a cross-sectional view of a fifth embodiment ring clamp.
Figure 6 is a cross-sectional view of a sixth embodiment fluid connection. Figure 7 is a cross-sectional view of a seventh embodiment fluid connector.
Figure 8 is a cross-sectional view of an eighth embodiment ring clamp.
Figure 9 is a cross-sectional view of a ninth embodiment ring clamp.
Figure 10 is a cross-sectional view of a tenth embodiment fluid connector. Figure 11 is a cross-sectional view of an eleventh embodiment fluid connector.
Figure 12 is a cross-sectional view of a twelfth embodiment fluid connector. Figure 13 is a cross-sectional view of a thirteenth embodiment fluid connector.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Figure 1 is a cross-sectional view of a cylindrical ring clamp 20 which provides an interference fit to secure a flexible hose 22 on barbs 24 formed on fitting 26. Ring clamp 20 may be manufactured from polymeric or metallic materials. Hose 22 is preferably manufactured from known polymeric or elastomeric materials. Typically, a rubber material is used. Fitting 26 is a fluid conduit having a cylindrical extending nipple 28 with barbs 24 extending radially outwardly therefrom. Fitting 26 may be manufactured from a polymeric or metallic material.
In assembling the first embodiment ring clamp 20 onto hose 22, ring clamp 20 is first positioned on hose 22 as illustrated in phantom at 29 in Figure 1. Ring clamp 29 is then moved along hose 22 and barbs 24 into an interference fit with an outer peripheral surface of hose 22. Ring clamp 20 includes an annular wall 30 having an outer circumferential surface 32 and an inner circumferential surface 34. Outer circumferential surface 32 is generally smooth. Inner circumferential surface 34 is also substantially smooth in the embodiment shown in Figure 1.
In preferred embodiments of the present invention, clamp ring 20 is formed of a material which is resistant to expansion or contraction over a wide temperature range.
Preferably, the material is resistant to thermal expansion or contraction over a temperature range from -40°F to 300°F. Further, clamp ring 20 is prefearbly formed of a material that has a lower coefficient of thermal expansion than the material of hose 22. In that way, it is. generally ensured that ring clamp 20 will retain its dimension and firmly secure hose 22 on fitting 26. Figure 2 illustrates a second embodiment ring clamp 35 having an annular wall member 30 with an inner peripheral surface 40 that includes a radially inwardly projecting member 42. Radially inwardly projecting member 42 has a semi-circular shape as shown in Figure 2. Projecting member 42 nests between adjacent barbs 24 to squeeze hose 22 into a depression formed between adjacent barbs 24. With this embodiment, it is still preferred that inner peripheral surface 40 defines an inner diameter that is less than the outer diameter of barbs 24 and the thickness of hose 22 such that there is also radially inward securement of hose 22 to connector 26 at each barb 24. The formation of member 42 may be such that it defines an inner diameter that is less than the outer diameter of barbs 24, and is resilient such that it deforms radially outwardly to allow passage over barbs 24.
Alternatively, the inner diameter of member 42 may be greater than the outer diameter of barbs 24, but less than the outer diameter of barbs 2 with the addition of hose 22. In this way, member 42 still squeezes hose 22 onto connector 26. Figure 3 shows a third embodiment ring clamp 49 having inner peripheral surface 50 with a pair of radially inwardly extending members 52 and 54, which are formed similar to member 42, and spaced between adjacent barbs 24.
Figure 4 shows a fourth embodiment of ring clamp 59 having an inner peripheral surface 60 with a radially inwardly projecting member 62 that has a rectangular shape. Figure 5 shows a fifth embodiment ring clamp 69 having an inner peripheral surface 70 with two radially inwardly extending members 72 and 74. Again, members 72 and 74 are generally rectangular in cross-section. The rectangular cross-section may be simpler to form than the semi- cylindrical cross-section of the earlier embodiments.
Figure 6 shows a sixth embodiment ring clamp 79 having inner peripheral surface 80 with a radially inwardly projecting member 82 having a cross-sectional shape of a truncated cone. Figure 7 shows a seventh embodiment ring clamp 89 having a pair of radially inwardly extending members 92 and 94 which are also truncated cone-shaped in cross- section. The truncated cone-shape inwardly projecting members 82, 92 and 94 present a ramped surface to thebarbs 24 as clamp 89 is being forced over hose 22. This reduces the force necessary to mount ring clamp 89 onto hose 22. Figure 8 shows an eighth embodiment ring clamp 99 having an inner peripheral surface 100 with a radially inwardly projecting member 102. Member 102 has a surface 103 extending perpendicularly to a central axis of ring clamp 99 and facing away from fitting 26. Member 102 also has a ramped surface 104 facing fitting 26 and a flat radially inner surface 106 which is squeezed between adjacent barbs 24. Figure 9 shows a ninth embodiment ring clamp 109 having an inner peripheral surface 110 with a pair of radially inwardly extending members 112 having a shape similar to member 102. The ramped surfaces 104 facing fitting 26 facilitates sliding movement of ring clamps 99 or 109 onto hose 22. The flat outwardly facing surfaces 103 prevent inadvertent removal of ring clamps- 99 or 109 by providing a stop against removal from barbs 24. Figure 10 shows a tenth embodiment ring clamp formed of a sing ring 200 which has an inner diameter greater than the outer diameter of barb 22, and less than the outer diameter of barb 22 with hose 22 received on it. In this way, ring 200 secures hose 22 onto fitting 26 by being squeezed between adjacent barbs 24. Figure 11 shows an eleventh embodiment ring clamp 210, wherein a pair of rings 200 are used.
Figure 12 shows a twelfth embodiment ring clamp wherein a ring 220 having a square cross-sectional shape is used to secure tube 22 to fitting 26. Figure 13 shows a thirteenth embodiment wherein a pair of rings 220 are used. In a method according to the present invention, a clamp member having an inner peripheral surface spaced from an axis of the ring clamp by a distance less than the combined outer diameter of the barbs and the flexible hose is slid onto the flexible hose to secure the flexible hose to the barbed fitting. The ring clamp may have radially inwardly extending members in any of a variety of shapes, an secures the hose onto the fitting. Further, the ring clamp is formed of a material that is more resistant to thermal deformation than the flexible hose. In this way, the ring clamp ensures that the hose will remain securely fastened onto the fitting over the normal operating ranges encountered by the fluid connection.
In one embodiment of the present invention, the ring clamp was formed of a polymeric material, one embodiment was formed of polyphenylene sulfide (PPS) . Filled polymers, and composite structures reinforced by other* material may also be used. Alternatively, the ring clamp can be formed of a metallic material. Preferably, a ferrous metal or aluminum is used.
Several preferred embodiments of the present invention have been disclosed, however, a worker of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. For that reason the following claims should be studied in order to determine the true scope and content of this invention.