1. Field of the Invention
The invention relates generally to the field of plumbing with flexible tubing. More specifically, the invention pertains to tools for removing cold formed, crimp rings commonly used with such plumbing.
2. Description of the Related Art
Flexible tubing has become prevalent in a wide range of plumbing applications-particularly where supply lines are required. Benefits include a significant savings in materials, installation, and time over traditional plumbing systems. In contrast to the threading or soldering required by traditional rigid systems, flexible plumbing is typically connected by simply sliding pieces of tubing over specialized plastic or metal fittings. Once the tubing is fitted, a ductile ring is crimped around the outside of the tubing to secure the connection. Insert fittings for the tubing are produced in a variety of configurations and are designed to form a tight connection with tubing of a particular size.
Besides being easy to install, flexible plastic plumbing systems have the potential to be easily modified and repaired. However, such work requires the disassembly of crimped ring connections. Typically the rings are cut and/or pried away from the outside of a given connection. Salvaging the rings is unnecessary due to their low cost. In contrast, the insert fittings are expensive and are generally worth re-using if possible.
Various methods and tools exist for removing crimp rings from flexible plumbing connections. A popular method involves sawing or grinding through the crimp ring while the connection is fully assembled. As would be expected, the method offers little precision, and too often results in damage to the tubing and internal fitting. This method also requires that the user have enough space to position and operate a saw or grinder, which is not commonly the case in many installations.
A similar method involves first cutting the tubing beyond the insert fitting, and then sawing or prying the ring from the remaining piece of tubing still present on the fitting. This method necessarily sacrifices some of the flexible tubing and may require additional struggle to extract the wasted length of tubing from the system.
Specialized crimp ring cutters are also available to ease the chore of removing rings. One example of such devices is plier-like in appearance and includes a pair of jaws. When operated, one of the jaws is inserted into the insert fitting hollow and the other is permitted to contact the crimp ring on the outside of the plumbing connection. Jaw travel is limited for the purpose of preserving the integrity of the insert fitting. As long as a short length of hose is able to be spared, such devices may be used for most flexible plumbing connections. However, this tool cannot accommodate the smallest common size tubing/fitting because of physical restraints.
The advantages of preserving flexible plumbing insert fittings and tubing lengths when removing crimp rings are exemplified in U.S. Pat. No. 6,769,181 to Scheuerman and U.S. Pat. No. 6,425,183 to Lemmens. The Scheuerman invention removes crimp rings by driving a fairly wide chisel blade in a path that is tangential to the inner diameter of the ring. By going no deeper than the thickness of the ring band, the invention avoids contact with the exterior tubing surface and preserves the underlying connection fitting. In contrast, the Lemmens tool directs relatively pointed cutting jaws toward the sides of a crimp ring band from opposing lateral directions, parallel to the direction of the tubing length. Since the cutting surfaces of the jaws are oriented away from the exterior tubing surface, damage to the underlying assembly is minimized.
While the plier-like devices are improvements over earlier methods, each is accompanied by its own disadvantages. All require significant force to shear the crimp ring band, which in some circumstances may be difficult to apply. Some require careful positioning to produce a cut which reliably preserves the underlying structures of the plumbing connection. Others are difficult to stabilize and may require repeated attempts before actually removing the ring. Still others can potentially damage the integrity of fittings when cutting force is transferred to internal components of the plumbing connection.
Therefore, there is a need for a crimp ring removal tool that is easily positioned to provide reliable and controlled penetration of crimp rings with minimal damage to plumbing connections, despite being operated in crowded or difficult confines.
Accordingly, the present invention is directed to an improved device and methods for removing cold formed crimp rings from flexible tubing connections. In a first aspect of the present invention, a device is adapted for removing crimped metal rings in conjunction with common auxiliary cutting tools. Guided by the device, the auxiliary tools serve to cut crimp rings in a rotating or reciprocating motion, thereby avoiding the need to transfer great force to a plumbing connection.
The collar-like tool of the present invention includes a bore within a collar block that is fitted closely to the outside dimensions of a flexible plumbing connection. The bore of the collar block is approximately equal to the outer diameter of flexible tubing that has been secured over an insert fitting. In preferred embodiments, the bore of the collar block is semi-cylindrical and contacts the outer circumference surface of the tubing for approximately 180 degrees. However, other shapes are also functional so long as the tool makes stable contact with the plumbing connection. In preferred embodiments, the collar block also includes one or more clamping areas, more or less opposite the bore, adapted for securing the tool and plumbing connection inside the jaws of a variety of clamping mechanisms such as locking pliers. After being tightened, the pliers hold the tool steadily in position over the plumbing connection as the crimp ring is being removed. In alternate embodiments, a clamping means is made integral with the construction of the collar block.
The collar block further comprises a ring slot within or adjacent to the bore and a guide path having plumbing and cutting tool ends. The ring slot is sized to fit closely over the crimp ring and serves to index the collar block to the flexible tubing connection. The guide path of the collar may be adapted for various cutting tools such as drills, grinders, or saws, and communicates with the ring slot so as to present the operative portion of the cutting tool to the crimp ring at the guide path plumbing end. Depending on the nature of the auxiliary cutting tool the collar may be constructed to limit the depth of cutting tool penetration, thereby protecting the components of the plumbing connection from becoming damaged. In alternative embodiments, specialized bits, blades, or stones incorporating depth limiting features may be adapted for preserving underlying connection components.
In accordance with the present invention, the collar block may include multiple bores and ring slot pairs corresponding to the outside dimensions of various standard tubing connection sizes. Furthermore, a single bore and ring slot pair may communicate with multiple guide paths, permitting the use of different cutting tools and allowing the plumbing connection to be approached from different directions according to the confines of a particular space. In further preferred embodiments, the collar block also comprises one or more sight paths for viewing the crimp ring as it is penetrated by the auxiliary cutting tool.
In a second aspect, methods are disclosed for removing crimp rings according to the present invention. Once indexed in position, the collar block device is secured in place. In preferred embodiments, the collar block is clamped to the flexible plumbing connection with locking pliers. After the collar block is stabilized, the operative portion of an auxiliary cutting tool is directed toward the plumbing connection through the guide path. The auxiliary tool is activated and permitted to contact the crimp ring. Sawing, drilling, or grinding is continued as progress is monitored until the ring is completely penetrated or until a stop is met. Depending on the skill of the operator, the collar block may be removed periodically if necessary to monitor the cut. In preferred embodiments, the operative portion of the auxiliary cutting tool is a drill or mill bit and progress of the cut is observed through the guide path upon removing the auxiliary cutting tool but without unclamping the collar block. In further preferred embodiments, a separate sight path is included in the collar block to observe the ring as it is being cut.
It is an object of the present invention to provide a portable, lightweight, inexpensive tool for efficiently removing crimp rings from flexible plumbing connections with minimal damage and waste.
It is a further objective to provide a crimp ring removal tool that, through its ring slot and bore size, is compatible with standard sized flexible plumbing connections.
It is another object the present invention to provide a crimp ring removal device compatible with common cutting tools likely to be owned by professionals or homeowners.
It is still another object to provide a tool and method for removing crimped rings such that critical plumbing components are conserved.
It is a further object to provide a tool adapted for operation in spaces that are cramped or otherwise difficult to approach with conventional crimp ring removal tools.
The present invention is directed to removing crimp rings from flexible plumbing systems having standardized external dimensions. Such systems are typically characterized by having plastic tubing conduit instead of rigid metal pipe. One popular flexible plumbing system incorporates cross linked polyethylene tubing joined with rigid insert fittings for use as water supply lines and is commonly referred to as PEX.
Shown in
In general, crimp rings 10 used with PEX plumbing are circular bands of malleable metal installed by compressing or cold forming the rings around fitted tubing ends. Since reliable plumbing connections require consistent deformation, crimp rings are manufactured to exacting tolerances. Similarly, the dimensions of tubing and insert fittings are carefully produced so as to permit measurement of the external diameter of the ring, after it has been crimped over its underlying components, to serve as a test of quality control.
As a result of the strict standardization of PEX water supply line system components, properly installed PEX connections can be expected to exhibit consistent external dimensions for any given component size. Tubing having outer circumferences of ⅜″, ½″, ¾″, and 1″ are most common. The corresponding external dimensions of completed connections for these sizes are given in Table 1 below.
As shown in
To remove a crimp ring using the device of
In all embodiments of the present invention the tool is collar-like, contacting or fitting closely around the outer circumference of a tubing end and over the outside diameter of a crimp ring in need of being removed. As shown in
As shown in
Still referring now to
In a further preferred embodiment of the invention, a crimp ring removal tool comprises a collar block 14 having three bore and ring slot pairs 40, each oriented in the same direction and corresponding to the dimensions of three different standard size PEX flexible plumbing connections, as shown in
As described and shown in the previous figures it is critical that the bore of the crimp ring removal tool communicates with at least one guide path to accommodate the operative portion of an auxiliary cutting tool. In further preferred embodiments multiple guide paths exist within a collar block to communicate with a single bore.
As shown in
Referring now to the invention in general, a crimp ring removal tool according to the present invention may be manufactured in several ways, depending on the material to be used and the desired performance to be obtained. In a preferred embodiment, the collar block is machined from a solid block of steel having a thickness adequate to span a crimp ring and provide sufficient bore length to establish a plumbing contact surface which continues along the tubing end on at least one side of the ring slot. In alternate embodiments, a crimp ring removal tool is cast or formed. The collar block may also be manufactured by bending a length of metal plate to resemble a collar block having an open bore. In most cases, the collar block can be subsequently completed by machining away unwanted material or welding on additional material as is needed to perform the function of removing a crimp ring. In general, a metal crimp ring removal tool should be hardened to provide a long lasting guide path. Hardening may be directed at the entire tool or only at specific areas likely to be altered by contact with other components such as the operative portions of auxiliary cutting tools. For tools employing a drill type auxiliary cutting tool, a hardened steel or equivalent guide path insert may be fitted within softer material serving as the balance of the tool.
In other embodiments of the invention, softer, lighter, and less durable materials may be substituted for metal to comprise the collar block, particularly if a disposable tool is desired. In still other embodiments, the tool is manufactured as a ceramic or composite having rugged materials at critical support or contact points, such as the guide paths and ring slots of the tool.
As is shown in
A further preferred embodiment of a crimp ring removal tool in accordance with the present invention is shown in
The surface of the second side 58 of the collar block 14 is divided into two portions by the small bore and ring slot pair 64. A higher portion 66 of the second side surface, opposite the large bore and ring slot pair, is farther from the first side of the collar block than a lower portion 68 of the second side opposite the medium bore and ring slot pair 62.
The collar block 14 further comprises clamping areas (not numbered) in proximity to the each guide path cutting tool end opening 65. The arcs of all three bores of the tool are approximately 180 degrees. However, the small bore and ring slot pair 64 located on the second side 58 of the collar block is asymmetrical so as to extend straight for a short distance 68 perpendicular to the second side 58 and adjacent with the higher portion 66 of the collar block.
In other embodiments, the bore and ring slot pair located on the second side of an opposing plumbing contact surface crimp ring removal tool is symmetrical. For instance, the second side of the collar block is made continuously parallel with the first side, without a high portion. Alternatively, a symmetrical bore and ring slot pair is located on the lower portion of the second side at a short distance from the high portion.
The quantity and arrangements of bore and ring slot pairs may also be varied for other opposing plumbing contact surface crimp ring removal embodiments. For example, the small bore and ring slot pair of a tool adapted to be indexed on three sizes of flexible plumbing connections is located on the same side of the collar block as the large bore and ring slot pair or a crimp ring removal tool in accordance with the present invention comprises only two bore and ring slot pairs having plumbing contact surfaces located on opposing sides of a collar block. Similarly, bore and ring slot sizes incorporated into the tool may be any one of various combinations.
In still other embodiments of crimp ring removal tools having open bore and ring slot pairs oriented in difference directions, collar blocks are substantially triangular or otherwise shaped to include non-parallel opposing sides. Moreover, drill type cutting tool guide paths in crimp ring cutting tool embodiments of the present invention may transverse collar blocks at a variety of angles while still being positioned in radial orientations to their respective ring slots and/or embodiments may include guide paths that do not run parallel to one another to provide better access for the operative portions of drill type cutting tools.
To clamp the removal tool of
As described herein, persons skilled in the art will understand that an improved crimp ring removal tool and methods have been disclosed which provides significant advantages over the prior art. The examples of embodiments provided are intended only as exemplary illustrations and not for the purpose of limiting the scope of claims to the present invention. Various changes, modifications, and equivalents in addition to those shown or described will become apparent to those skilled in the art and are similarly intended to fall within the spirit and scope of the invention whether or not they presently exist in the following or are later made in amended claims.
This application claims the benefit of U.S. Provisional Patent Application No. 61/790,119, filed Mar. 15, 2013, the disclosure of which is herein incorporated by reference.
Number | Date | Country | |
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61790119 | Mar 2013 | US |