Holderless hose clamp

Abstract: A hose clamp (100) comprises a clamp ring (101) made of a metal strip rolled into a loop with its ends overlapping each other. First and second pinches (102,103) are projected up from the ends of the metal strip (101) in the radial direction. The first pinch (102) has a frame (102a), which defines an opening (108a) inside the frame (102a), and a stopper wall (105) swelling into the inside opening (108a) from a corner of the frame (102a). The second pinch (103) has an operation chip (106) extending in the width direction of the clamp ring (101). A stopper (107) rises from the clamp ring (101) near the root of the second pinch (103). The hose clamp (100) has a clamping position, at which the first and second pinches (102,103) are apart from each other, and a loosened position, at which the first and second pinches (102,103) are very close to each other. At the loosened position, the operation chip (106) of the second pinch (103) sticks out from the clamp ring (101) in the width direction of the clamp ring (101).

Description: This invention relates to an improved arrangement of a hose clamp suitable for attaching a rubber hose to the end of a connection pipe which does not require a separate holder to keep the hose clamp at a loosened position. A hose clamp is used to attach a rubber hose to a pipe. In general, hose clamp has a clamping position for tightening the hose against the outer wall of the pipe, and a loosened position for allowing the end of the pipe to be inserted into the hose. A holderless-type hose clamp, which does not require a separate holder for retaining the clamp at a loosened position, has been proposed in, for example, Japanese Patent Application Laid-open No. 10-61855. Fig. 1 illustrates an example of such holderless-type hose clamp. The hose clamp 1 is comprised of a clamp ring 2 made of a strip of spring leaf rolled into a loop with the ends overlapping each other. First and second pinches, or projections, 6 and 9 extend from the ends of the clamp ring 2, and are projected up in the radial direction of the clamp ring 2. The first pinch 6 includes a frame having the same width as the clamp ring 2, combined with an opening. The opening is connected with a guide groove formed in the clamp ring 2. The frame has a projection 7 extending in the radial direction. A stopper 11 extends from the frame toward the inside opening with its end 12 bent zigzagly down. The width of the second pinch 9 is narrower than that of the first pinch 6, and is movable in the guide groove. The second pinch 9 has a tooth 14 and a shifting edge 9a that can be displaced by axial movement of the second pinch 9 under an external force. In the natural state, the clamp ring 2 is at a clamping position by its own restoring force. To loosen the clamp ring 2 in order to receive a pipe, a pair of pliers is used to bring the pinches 6 and 9 closer to each other along the circumference of the clamp ring 2. The tooth 14 of the second pinch 9 gets behind the stopper 11 of the first pinch 9, and then, it is meshed with the stopper 11. In this state, the clamp ring 2 is held at a loosened position, and a pipe is inserted in the hose. To release the engagement between the tooth 14 and the stopper 11, the shifting edge 9a of the second pinch 9 is displaced by pliers in the radial direction, thereby being moved away from the stopper 11. The displacement of the shifting piece 9a causes the tooth 14 to be disengaged from the stopper 11. Consequently, the clamp ring 2 restores to the clamping position having its own restoring force, and tightens the hose against the pipe. This type of conventional hose clamp does not require a separate holder to retain the pinches at a closer position to keep the clamp ring 2 loose. However, the conventional hose clamp illustrated in Fig. 1 has problems in size and reliable disengagement of the tooth 14 from the stopper 11. In releasing the engagement, the edge of the projection 11 of the first pinch 6 and the shifting edge 9a of the second pinch 9 are held by a pair of pliers, and moved in the axial direction of the clamp ring 2. For this reason, the projection 7 of the first pinch 6 and the shifting edge 9a of the second pinch 9 must have a sufficient size to allow the pliers to grasp the edge of projection 7 and the shifting edge 9a. This means that the pinches 6 and 9 can not be made smaller in the radial direction. If the pinches 6 and 9 are made too small, then they can not be held by the pliers because the projection 7 and the shifting edge 9a, both extending in the radial direction of the clamp ring 2, become insufficient. The stopper 11, which extends into the opening, also inhibit the pliers from reliably grasping the shifting edge 9a. In addition, since the shifting edge 9a is entirely positioned within the width of the frame of the first pinch 6, the pliers are very likely to slip from the shining edge 9a. US-A-5 819 376 discloses a hose clamp comprising: a resilient clamp ring having two ends which overlap in a circumferential direction of the ring; first and second projections which extend radially from respective said ends, wherein the first projection comprises a frame defining an opening; and a stopper which projects from a position of the clamp ring near the root of the second projection; wherein the hose clamp has a clamping position at which the first and the second projections are spaced apart from each other, and a loosened position at which the stopper abuts resiliently against a face of the first projection to hold the clamp ring in the loosened position; and wherein said stopper is disengageable from said stopper wall by movement of said first and said second projections away from each other in the radial direction. US-A-5 419 905 discloses a hose clamp comprising: a resilient clamp ring having two ends which overlap in a circumferential direction of the ring; and first and second projections which extend radially from respective said ends, wherein the first projection comprises a frame defining an opening and two stopper walls projecting from respective comers of the frame into the opening; and wherein the hose clamp has a clamping position at which the first and the second projections are spaced apart from each other, and a loosened position at which the second projection abuts resiliently against respective faces of the stopper walls to hold the clamp ring in the loosened position; and wherein the second projection is disengageable from said stopper walls by movement of said first and said second projections away from each other in the radial direction. The present invention was conceived to provide an improved hose clamp. The present invention provides a hose clamp comprising: a resilient clamp ring having two ends which overlap in a circumferential direction of the ring; and first and second projections which extend radially from respective said ends, wherein the first projection comprises a frame defining an opening and stopper wall projecting from a comer of the frame into the opening, and wherein the second projection comprises an operation extension which extends in the axial direction of the ring; and a stopper which projects from a position of the clamp ring near the root of the second projection; wherein the hose clamp has a clamping position at which the first and the second projections are spaced apart from each other, and a loosened position at which the stopper abuts resiliently against a face of the stopper wall to hold the clamp ring in the loosened position; and wherein the operation extension of the second projection extends axially outwardly from a side edge of the first projection at the loosened position of the clamp ring and said stopper is disengageable from said stopper wall by movement of said first and said second projections together in the axial direction. Other preferred aspects of the invention are defined in the accompanying claims. A hose clamp of an embodiment of the present invention is described hereinafter and includes a clamp ring made of a metal strip rolled into a loop with its ends overlapping each other. The clamp ring has a restoring force. First and second pinches are projected up from the ends of the metal strip in the radial direction. The first pinch has a frame that defines an opening inside it, and a stopper wall swelling into the inside opening from a corner of the frame. The second pinch gets through the opening of the first pinch, so that the first and second pinches cross each other. The second pinch has an operation chip extending in the width direction of the clamp ring. A stopper rises from the clamp ring near the root of the second pinch. The hose clamp has a clamping position, at which the first and second pinches apart from each other, and a loosened position, at which the first and second pinches very close to each other. At the loosened position, the operation chip of the second pinch sticks out from the clamp ring in the width direction of the clamp ring. When the hose clamp is brought into the loosened position, the stopper gets out of the opening of the first pinch, and abuts against the rear face of the stopper wall at the loosened position, whereby the clamp ring can be kept at the loosened position. Preferably, the stopper wall has a hook, which prevents the stopper from slipping off from the stopper wall at the loosened position. Preferably, the hook is made monolithically with the stopper wall. These arrangements allow the hose clamp to be made compact, while allowing the users to easily and reliably loose and tighten the hose clamp. In addition, the hose clamp can be kept at the loosened position in a safe manner. In order that the present invention may be welll understood, an embodiment thereof, which is given by way of example only, will now be decribed with reference to the accompanying drawings, in which: Fig. 1 illustrates a conventional hose clamp, in which Fig. 1A shows the hose clamp in the clamping position, and Fig. 1B shows how the clamp ring is released from the loosened position; Fig. 2 illustrates in two different views a hose clamp according to an embodiment of the invention; Fig. 3 is a side view of the hose clamp shown in Fig. 2; Fig. 4 illustrates in a perspective view how the hose clamp of Fig. 2 is retained at the loosened position; Fig. 5 illustrates in a side view how the hose clamp of Fig. 2 is retained at the loosened position; and Fig. 6 illustrates how the hose clamp of Fig. 2 is released from the loosened position. Fig. 2 illustrates a hose clamp 100 according to the preferred embodiment of the invention. A feature of the hose clamp 100 of the present invention resides in the shapes of the first (i.e., the wider) pinch, or projection, 102 and the second (i.e., the narrower) pinch, or projection, 103. The hose clamp 100 comprises a resilient clamp ring 101 made with a metal strip rolled into a loop, and a pair of pinches 102 and 103 projecting up in the radial direction from the ends of the clamp ring 101 and crossing each other in a circumferential direction, as shown in Fig. 3. The first pinch 102 includes a frame 102a having the same width as the clamp ring 101. The frame 102a defines an opening 108a inside it. A guide groove 108 extends along the clamp ring 101 near the first pinch 102, and is connected to the opening 108a. The first pinch 102 also has a stopper wall 105 swelling (projecting) into the inside opening 108a from a corner of the frame 102a. The stopper wall 105 has a small hook 105a bending outward (i.e., away from the second pinch 103), as shown in Figs. 2B and 3. The second pinch 103 is passed through the opening 108a of the first pinch 102, and is positioned in the guide groove 108, so that the first and second pinches 102 and 103 cross each other in the circumferential direction. The second pinch 103 includes an operation chip, or extension, 106 extending in the axial direction of the clamp ring 101. The clamp ring 101 has a stopper 107 rising from the root of the second pinch 103. In the normal state, the clamp ring 101 is at a clamping position under its own restoring force. To bring the clamp ring 101 to a loosened position, an external force is applied so as to bring the first and second pinches 102 and 103 close to each other, while slightly shifting the second pinch 103 in the width (axial) direction of the clamp ring 101. Namely, the second pinch 103 is slightly pushed away from the stopper wall 105 of the first pinch 103. Under the external force, the second pinch 103 moves toward the first pinch 102 along the guide groove 108, and the stopper 107 rising from the root of the second pinch 103 passes through the opening 108a. Then, if the external force is removed, the stopper 107 abuts against the rear face of the stopper wall 105 of the first pinch 102, as shown in Figs. 4 and 5. In this state, the clamp ring 1 is prevented from restoring to the clamping position because of the contact between the stopper 107 and the stopper wall 10, and is kept at a loosened position. Then, a pipe is inserted in a hose, which is allowed by the loosened hose clamp 101. The hook 105a of the stopper wall 105 of the first pinch 102 prevents the stopper 107 from slipping off the stopper wall 105 when the clamp ring 101 is kept at the loosened position. In other words, the hook 105a allows the stopper 107 to keep the clamp ring 101 loose in a reliable manner. To loosen the clamp ring 101, an external force is applied by, for example, a pair of pliers, which bring the first and second pinches 102 and 103 close to each other. At the loosened position, if the external force is removed, the operation chip 106 of the second pinch 103 sticks out from the side edge 104a of the first pinch 102 in the width direction of the clamp ring 101, as shown in Fig. 4. To release the engagement between the stopper 107 and the stopper wall 105, the operation chip 106 of the second pinch 103 and the side edge 104b of the first pinch 102 are grasped by pliers, as shown in Fig. 6. The operation chip 106 of the second pinch 103 extends axially outwardly from the side edge 104a of the first pinch 102 and therefore the operation chip 106 can readily be grasped by the pliers P. The opposing edge 104b of the first pinch 102 is positioned outwardly from the operation extension in an opposite axial direction. Accordingly, the edge of the operation chip 106 and the side edge 104b of the first pinch 102 frame stick out from each other in the width direction of the clamp ring 101 without any obstacles, and therefore can be reliably grasped by the pliers. Then, the first and second pinches 102 and 103 are slid together in the width direction of the clamp ring 101 in such a manner that the stopper 107 slides over the stopper wall 105. Once the stopper 107 is disengaged from the stopper wall 105, the clamp ring 101 returns to the clamping position by its own restoring force. As the feature of the embodiment, the operation chip 106 of the second pinch 103 extends in the lateral direction, that is, in the width direction of the clamp ring 101, unlike the conventional hose clamp that has a projection (or an operation chip) extending in the radial direction. While the operation chip 106 can be made large because it is not limited in size in the radial direction, the second pinch 103 itself can be made very small, whereby the hose clamp 100 can be made compact. The sufficient size of the operation chip 106, which sticks out of the width of the clamp ring 101, allows the pliers to reliably grasp the first and second pinches, and to readily disengage the stopper 107 from the stopper wall 105. The hook 105a of the stopper wall 105 allows the stopper wall 105 to stop the stopper 107 without fail, thereby keeping the clamp ring 101 at the loosened position in a reliable manner. The hook 105a may be formed integrally with the stopper wall 105, which facilitates the manufacturing process of the clamp ring 101. It should be noted that, besides those already mentioned above, many modifications and variations may be made without departing from the novel and advantageous features of the present invention as defined by the following claims. Although the hook, which is manufactured integrally with the stopper wall, is used to prevent the stopper slipping off the stopper wall, any other suitable means may be used. For example, a separate chip or a rubber may be attached to the rear face of the stopper wall near the vertex of the swelling portion.

Claims: A hose clamp comprising: a resilient clamp ring (101) having two ends which overlap in a circumferential direction of the ring; and first and second projections (102,103) which extend radially from respective said ends, wherein the first projection (102) comprises a frame (102a) defining an opening (108a) and stopper wall (105) projecting from a comer of the frame into the opening, and wherein the second projection (103) comprises an operation extension (106) which extends in the axial direction of the ring; and a stopper (107) which projects from a position of the clamp ring near the root of the second projection; wherein the hose clamp has a clamping position at which the first and the second projections are spaced apart from each other, and a loosened position at which the first and second projections are close to each other and at which the stopper abuts resiliently against the rear face of the stopper wall to hold the clamp ring in the loosened position; and wherein the operation extension of the second projection extends axially outwardly from a side edge (104a) of the first projection at the loosened position of the clamp ring and said stopper is disengageable from said stopper wall by movement of said first and said second projections together in the axial direction. A hose clamp as claimed in claim 1, wherein, during expansion of the clamp ring (101) to the loosened position, the stopper (107) is passed through the opening (108a) of the first projection (102) to abut against the rear face of the stopper wall at the loosened position. A hose clamp as claimed in claim 1 or 2, wherein the stopper wall (105) has a slip-prevention means (105a) for preventing the stopper from slipping off from the rear face of the stopper wall at the loosened position. A hose clamp as claimed in claim 3, wherein the slip-prevention means is a hooked portion (105a) integrally formed with the stopper wall (105). A hose clamp as claimed in any preceding claim, wherein the clamp ring (101) has a circumferentially extending groove (108) which opens into the opening (108a) and along which the second projection (103) can be moved between the clamping position and the loosened position.

Inventors: YAMADA SATOSHI, YAMADA, SATOSHI, Yamada, Satoshi, c/o Piolax Inc.
Applicants: PIOLAX INC, PIOLAX INC.
Application year: 2000
Main classification: F16L33
IPC codes: F16L33