Ear clamps with cup lock hook system

Abstract

EAR CLAMP WITH CUP LOCK HOOK SYSTEM. The present invention relates to an ear clamp (10) comprising a clamp band (12) and a fastening structure (14), the clamp band (12) comprising an outer clamp band end (12a) and an inner clamp band end (12b), the inner clamp band end (12b) including a first hook (16) which passes through an opening (18) in the outer clamp band end (12a) in the closed position. It is proposed that the opening (18) is slit-shaped in a top view of the band, the length of the opening (18) extending in the transverse direction of the clamp band (12).

Description

[Background technology]

[0001] The present invention relates to ear clamps for connecting pipes, particularly pipes made of PEX (polyethylene) material commonly used in the plumbing industry, to an object to be inserted into the pipe, such as a pipe fitting.

[0002] WO 2015 / 022024 discloses a typical open ear clamp with a so-called Oetika ear type fastening arrangement, which in the closed position has a hook that passes through a window in the outer clamp band end, the window being punched out of the band material.

[0003] WO 2021 / 104918 discloses a band clamp having a plurality of hooks and windows that can be engaged with each other to close the clamp.

[0004] Existing hook designs have large openings in the band material where material is punched out, resulting in material waste. In some designs, the hook alone, rivet locks, and fixed hooks engage windows with these large openings. The openings are expanded both lengthwise and widthwise of the band, reducing the total amount of band material in the longitudinal region of the band with the window. As a result, tension forces applied to the clamps are concentrated on the side webs on either side of each window. This is accompanied by increased stretching of the band in this region, as the cross section of the window / opening area is reduced. This reduces the force transmission and reduces performance. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2015 / 022024 [Patent Document 2] International Publication No. 2021 / 104918 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention seeks to improve the performance of the clamp by improving the closure elements for closing the clamp, in particular by improving the structure of the interlocking hooks and / or windows. [Means for solving the problem]

[0007] This problem is solved by a device having the features of claim 1. Advantageous embodiments of the invention are defined by the dependent claims.

[0008] The present invention relates to an ear clamp having a clamp band and a fastening structure, the clamp band comprising an outer clamp band end and an inner clamp band end, the inner clamp band end including a first hook that, in a closed state, passes through an opening in the outer clamp band end.

[0009] It is proposed that the opening is slit-shaped in the top view of the band. In the context of the present invention, slit-shaped means longer than it is wide. To quantify the aspect ratio of the slit shape, it is proposed that the length of the opening in the transverse direction of the clamping band is at least 5 times the width of the opening in the longitudinal direction of the clamping band. The slit shape prevents the occurrence of wasted material volume.

[0010] The clamping band has an inner side which, in the closed state, is directed towards the hose or tube and / or towards the inside of the ring formed by the clamp, and an outer side which is directed radially outwards, such that in the closed state, the inner side of the outer clamping band end is in contact with the outer side of the inner clamping band end, the inner side of the inner band end is in contact with the hose or tube, and the outer side of the outer band end is freely accessible from the outside.

[0011] The clamp band has a longitudinal direction and a lateral direction, the latter being the width direction of the band. The thickness direction of the clamp band is perpendicular to both of these directions. A top view of the band is a view from the outside in the thickness direction of the band.

[0012] A smaller width slit shaped opening means that the length of the band section weakened by the opening is smaller, resulting in less stretch in the band and therefore improved performance.

[0013] In a preferred embodiment of the invention, the material of the band is domed on the side of the opening facing the fastening structure to form a cup configured to receive the first hook. By creating an opening in the side wall of the first dome, the cup facilitates engagement of the hook with the opening even if the opening is linear in top view.

[0014] In a preferred embodiment of the invention, the width of the cup is greater than the width of the opening and tapers towards the opening, and as will be described in more detail below, the side walls of the cup help guide the first hook into the opening and may also create a wedge effect that takes the load off the hook.

[0015] It is further proposed to form a first hook at the tip of the wedge-shaped projection which is adapted to wedgedly couple with the inner side of the dome, the wedge effect and the guide effect being independent of the hook.

[0016] In a further preferred embodiment of the invention, the material of the band is bent downwards on the side of the opening facing away from the fastening structure to form a lower hook configured to wedgedly engage with the upper hook, the wedging of the lower hook and the upper hook pressing down on the band, which allows the hook to transmit a greater force from the upper band to the lower band.

[0017] We propose that the opening is arc-shaped with the convex side facing the fastening structure, so that the convex side can be easily folded to form the lower hook, as explained above.

[0018] In a preferred embodiment of the invention, the openings are cut, for example by lancing, without punching material out of the band.

[0019] The inventors further propose that the aperture and / or the structure around the first hook be formed by a material deformation process that results in cold hardening of the material, which further increases the stability of the band and reduces unintended deformation and band elongation.

[0020] According to a further aspect of the invention, reinforcing dimples are formed adjacent the openings, which can improve force distribution and force transfer in the area of ​​interest.

[0021] Preferably, only the upper side of the clamp band is embossed with the reinforcing dimples, the underside of the clamp band being flat at the location of the reinforcing dimples.

[0022] Further features and advantages will become apparent from the following description of the embodiments and drawings. The specification, claims and drawings as a whole disclose the features of the invention in specific embodiments and combinations. Those skilled in the art will also be able to consider the features individually and combine them into further combinations or subcombinations to adapt the invention defined in the claims to their needs or specific application. [Brief description of the drawings]

[0023] FIG. 1 is an ear clamp according to the present invention; Fig. 2 is a detailed view of the closing structure of the ear clamp according to Fig. 1; Fig. 3 is a detailed view of the cup structure of the outer band end of the ear clamp according to Fig. 1; Fig. 4 is a top view of the cup structure of Fig. 3; Fig. 5 is a detailed view of the inner end of the clamp band, which has two wedge-shaped hooks; Fig. 6 is a detailed view of one of the wedge-shaped projections of Fig. 5; Fig. 7 is a top view of the wedge-shaped projection of Fig. 6; FIG. 8 is a longitudinal section of the closing structure of the ear clamp according to the present invention; FIG. 9 is a longitudinal section parallel to the band plane showing the force transmission area of ​​the ear clamp closing structure according to the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] FIG. 1 shows an ear clamp 10 according to the present invention.

[0025] The ear clamp 10 shown in FIG. 1 includes a clamp band 12 and a fastening structure 14, where the clamp band 12 includes an outer clamp band end 12a and an inner clamp band end 12b.

[0026] The fastening structure 14 is a so-called "Oetika ear" and has two radially outwardly extending legs 14a, 14b and a web 14c interconnecting the outer ends of the legs 14a, 14b. The web 14c of the ear is stamped with a recess to prevent buckling. The inner clamping band end 12b is extended by a tongue 12c that is guided by two side walls and an inwardly projecting step of a recess formed by pressing the clamping band 12. In an alternative embodiment, the tongue may be guided by a transverse strap created by a longitudinal cut.

[0027] In use, the ear clamp 10 is placed around a tube at the location where an object such as a fitting (not shown) is inserted into the tube.

[0028] Fig. 2 is a detailed view of the closing structure of the ear clamp 10 according to Fig. 1. The inner clamp band end 12b includes two first hooks 16 which pass through corresponding openings 18 of the outer clamp band end 12a in the closed state. The hooks 16 and the openings 18 are also called the closing structure of the ear clamp 10.

[0029] Fig. 3 is a detailed view of the cup structure of the outer clamp band end 12a of the ear clamp 10 according to Fig. 1, and Fig. 4 is a top view of the cup structure of Fig. 3. The opening 18 is slit-like in the top view (Fig. 4) of the clamp band 12 and is formed as a cut without punching material from the clamp band 12, also called lancing. The clamp band 12 further includes an embossed structure, and the cut may be formed by an embossing process or a separate cutting process. The opening 18 is arc-shaped with the convex side facing towards the fastening structure 14.

[0030] During the embossing process, the incision is opened in the thickness direction of the band by producing opposite deformations on both sides of the incision, thus forming an opening 18. On the side of the incision facing the clamping structure 14, the material of the clamping band 12 rises in a dome-like shape to form a cup 20 configured to receive a projection (FIG. 5) on the inner clamping band end 12a, including the first hook 16. The width of the cup 20 in the transverse direction of the clamping band 12 is greater than the width of the opening 18 and narrows towards the opening 18 so as to form a wedge shape. The inner wall of the cup 20 is essentially upright, i.e. perpendicular to the main plane of the clamping band 12. The opening 18 is formed on the front side of the cup 20 and has a height in the thickness direction of the band that substantially corresponds to the thickness of the band material so as to accommodate the first hook 16.

[0031] 5 to 7 are detailed views of the inner end of the clamp band 12 having two wedge-shaped projections 24 with hooks 16. The inner end of the clamp band 12 is formed with the wedge-shaped projections 24 configured to form a wedge connection with the inner side surface of the first dome. The first hook 16 is formed at the tip of the wedge-shaped projections 24. A small recess 26 is formed below the first hook 16 to accommodate the lower hook 22.

[0032] Returning to FIG. 3, note that on the side of the opening 18 facing away from the fastening structure 14, the material of the band is bent downwardly to form a tab that moves a lower hook 22 that is configured to wedge engage with the upper hook 16.

[0033] Both the cup 20 and the wedge projection 24 have a wedge-shaped base with a side wall and a top wall, with further structure embossed in the top wall. The top wall of the cup 20 has a smaller wedge-shaped dome 20a configured to receive the first hook 16. The first hook 16 is configured to project beyond the top wall of the wedge projection 24. This structure separates the wedge effect of the base side walls from the upper and lower hooks 16, 22 compressing against the inner and outer clamp band ends 12a, 12b.

[0034] Fig. 8 is a longitudinal section of the closing structure of the ear clamp 10 according to the present invention. To close the clamp 10, the first hook 16 is engaged with the corresponding opening 18 to create a pre-assembly state. Then, the clamp 10 is tightened around the tube by narrowing the width of the ear of the clamping structure 14, i.e., by pressing the legs 14a, 14b of the clamping structure 14 together, for example with a pliers-type tightening tool, to form a sealed connection between the tube and the object. The clamping force is not only transmitted through the hook 16 and the lower edge of the opening 18, but rather draws the wedge-shaped projection 24 into the wedge-shaped inner wall of the cup 20 so as to be distributed between the wall of the cup 20 and the projection 24 and between the hook 16 and the opening 18. Thus, the load on the hook 16 alone is reduced compared to the prior art. At the same time, the upper hook 16 wedges with the lower hook 22 to press the wedge-shaped projection 24 against the wedge-shaped inner wall of the cup 20. This allows the hook 16 and the wall around it to transmit a greater force from the outer clamp band end 12a to the inner clamp band end 12b.

[0035] FIG. 9 is a longitudinal cross-section showing the outer wall of the wedge-shaped projection 24 abutting the inner wedge wall of the cup 20 for force transmission in a force transmission area 28 shown in dashed lines.

[0036] The size of the opening 18 used for hooking onto the hook 16 is minimized. No material is punched out of the band to form the opening 18, but merely cut. The opening 18 extends only in the width direction of the clamping band 12, thus realizing a minimal longitudinal expansion of the reduced cross-section.

[0037] The structure including the cup 20 and the wedge-shaped projection 24 around the opening 18 and / or the first hook 16 is formed by a material deformation process, in particular embossing, which results in cold hardening of the material.

[0038] In addition to the latter structure, a reinforcing dimple 30 is formed adjacent the opening 18. The reinforcing dimple 30 is embossed only on the upper side of the clamp band 12, the underside of the clamp band 12 being flat at the location of the reinforcing dimple 30.

[0039] The design of the hooks 16 and openings 18 according to the invention minimizes band stretching by reducing the size of the hook-in openings 18 and reinforcing the areas with small hook-in openings 18 with reinforcing dimples 30. This optimization allows for a higher breaking force and a more powerful clamp. This design ensures that the clamp will not open unintentionally. No additional locking hooks or rivet locks are required for this purpose. The improved force transmission allows the same force to be transmitted with fewer hooks 16, which reduces the overall length of the clamp band 12 and reduces material consumption. The small size and lack of locking hooks 16 or rivet locks further saves material requirements. However, the hooks 16 according to the invention can be supplemented by additional locking hooks (not shown) of conventional design.

[0040] The present invention provides several improvements over existing band clamps, namely, increasing the force transmission per hook 16, minimizing band stretch in the area of ​​the hook 16, and reducing the amount of material required.

[0041] Due to the V-shape of the cup 20 , the force is not only transferred to the front surface of the hook 16 , but also to two sides of the hook 16 , namely the sides of the base of the wedge-shaped projection 24 .

[0042] The inventors conducted an expansion test of the hook 16 and found that the breaking strength of the new hook 16 design is 12'000N (~+12%) higher than the hook 16 as disclosed in WO 2015 / 022024 or WO 2021 / 104918. [Explanation of symbols]

[0043] 10 Ear Clamps 12 Clamp band 12a outer clamp band end 12b Inner clamp band end 14 Fastening structure 16 Hook 18 Aperture 20 cups 22 Lower hook 24 Cuneiform process 26 Recess 28 Force transmission area 30 Reinforcement dimples

Claims

1. An ear clamp comprising a clamp band (12) and a fastening structure (14), The clamp band (12) comprises an outer clamp band end (12a) and an inner clamp band end (12b), the inner clamp band end (12b) includes a first hook (16) that passes through an opening (18) of the outer clamp band end (12a) in a closed state; In a top view of the band (12), the opening (18) is slit-shaped, and the length of the opening (18) extends in the lateral direction of the clamp band (12). An ear clamp characterized by:

2. 2. The ear clamp of claim 1, the length of the opening (18) in the lateral direction of the clamping band (12) is at least five times the width of the opening (18) in the longitudinal direction of the clamping band (12); An ear clamp characterized by:

3. 3. An ear clamp according to any one of claims 1 and 2, the band material is domed on one side of the opening (18); An ear clamp characterized by:

4. 4. An ear clamp according to any one of claims 1 to 3, the material of the band is domed on the side of the opening (18) facing the fastening structure (14) to form a cup (20) configured to receive the first hook (16); An ear clamp characterized by:

5. 5. The ear clamp of claim 4, The width of the cup (20) is greater than the width of the opening (18) and decreases toward the opening (18). An ear clamp characterized by:

6. 6. The ear clamp of claim 5, The first hook (16) is formed at the tip of a wedge-shaped projection (24) configured to wedge with the inner side of the dome. An ear clamp characterized by:

7. 7. An ear clamp according to any one of claims 1 to 6, The material of the band is bent downwards on the side of the opening (18) facing away from the fastening structure (14) to form a lower hook (22) configured to wedge-fit with the upper hook (16). An ear clamp characterized by:

8. 8. An ear clamp according to any one of claims 1 to 7, The opening (18) is arc-shaped with a convex side facing the fastening structure (14). An ear clamp characterized by:

9. 9. An ear clamp according to any one of claims 1 to 8, the openings (18) are formed as cuts without punching material from the band; An ear clamp characterized by:

10. 10. An ear clamp according to any one of claims 1 to 9, the opening (18) and / or the structure around the first hook (16) are formed by a material deformation process resulting in cold hardening of the material; An ear clamp characterized by:

11. 11. An ear clamp according to any one of claims 1 to 10, A reinforcing dimple (30) is formed adjacent to the opening (18). An ear clamp characterized by:

12. 12. The ear clamp of claim 11, The reinforcing dimples (30) are embossed only on the upper side of the clamp band (12), and the lower side of the clamp band (12) is flat at the location of the reinforcing dimples (30). An ear clamp characterized by:

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