The present reference claims priority from United Kingdom Patent No. GB0423469.6 filed Oct. 22, 2004, the entire contents of which are herein incorporated by reference.
1. Field of the Invention
The present invention relates generally to a device for cutting pipes, tubing and the like. More specifically, the present invention relates to a powered or powerable pipe cutting device for the automated cutting of pipes, tubing and the like.
2. Description of the Related Art
It is known, for example from U.S. Pat. No. 4,831,732 and GB2288353, to provide a manual pipe cutting device comprising a cylindrical body with a longitudinal radial entry slot into which a pipe can be introduced. As the cylindrical body is manually turned around the pipe a cutting wheel is biased into contact with the pipe and progressively cuts into the pipe.
The advantage of a body with a radial slot is that it allows the pipe cutter to be introduced at any point along the length of the pipe as opposed to configurations without a slot, such as that shown in EP 0 483 076, in which a pipe must be inserted longitudinally through a cutting device. The presence of the radial slot allows, for example, the pipe cutter to be introduced to a pipe which is already connected at both ends and therefore does not have a free end over which the pipe cutter can be passed, and to be easily introduced to long pipes.
Referring now to
The generally C-shape configuration of the body 2 allows the cutting member 1 to be placed around a cylindrical pipe 5 at a desired cutting point, with the pipe 5 resting in the semi-circular recess provided by the bight 4c. The cutting member 1 includes cutting means (not shown) operable such that when the body 2 is rotated about the longitudinal axis of the pipe 5 a cutting blade or the like is biased into contact with the pipe 5 and progressively produces a cut transverse its length. For the sake of simplicity and brevity the exact details of the cutting means are not described herein are asserted to be known to those of skill in the art.
A variety of cutting mechanisms have been proposed, such as in patent documents U.S. Pat. No. 4,831,732 and GB2288353 (both incorporated herein by reference), and all that is required for such cutting mechanisms is that the cutting member cuts the pipe when rotated about the longitudinal axis thereof.
What is not appreciated by the prior art is the need for an automated drive for a pipe cutter readily adapted to a variety of drive-power sources.
Accordingly, there is a need for an improved pipe cutting device.
An object of the present invention is to provide an improved pipe cutting device readily adapted to an automated drive assembly and a variety of drive-power sources, as will be discussed.
The present invention relates to a pipe cutting device. The device is based on a cutting member having a body with a radial pipe entry slot for receiving a pipe at a required cutting position along its length and having cutting means for cutting the pipe upon rotation of the cutting member around the pipe. The device comprises a drive member having drive means for causing the cutting member to rotate. The drive means is adapted to provide continuous drive to the cutting member body. Drive is not temporarily lost as the pipe entry slot rotates passed the drive means.
The present invention is based on the desire to provide automated drive to a pipe cutter of the known type described above. The problem addressed is to provide uninterrupted drive to a body having a generally C-shape configuration hich includes a radial slot and in particular to provide drive over the gap in the body defined by the radial slot.
According to a first aspect of the present invention there is provided a drive device for causing rotation of a cutting member of the type having a body with a radial pipe entry slot for receiving a pipe at a required cutting position along the length thereof, and having cutting means for cutting a pipe upon rotation of the body about a longitudinal axis thereof; the drive device comprising drive means for causing the cutting member body to rotate relative thereto, in which, in use the drive means is formed so as to provide substantially continuous drive to the cutting member body.
The drive device may further comprise a cutting member. The cutting member may be provided as an integral part of the drive device or may be provided as a separate unit which is associatable with the drive device.
According to a second aspect of the present invention there is provided a pipe cutting device comprising: a cutting member having a body with a radial pipe entry slot for receiving a pipe at a required cutting position along the length thereof, and having cutting means for cutting a pipe upon rotation of the cutting member about the longitudinal axis thereof; and drive means for causing the cutting member to rotate relative thereto, in which, in use, the drive means is formed so as to provide substantially continuous drive to the cutting member body.
The present invention therefore provides a device incorporating or adapted to incorporate a cutting member of a known general type in which rotation is used to cut a pipe. Drive means for causing the cutting member body to rotate are provided and as a result the body rotates relative to the drive means. In order to provide substantially continuous drive to the cutting member body the drive means is formed so as to be in substantially continuous driving engagement with the body. Substantially uninterrupted drive is therefore provided to the cutting member body and this facilitates the automation of the cutting process where previously it had not been possible because of the requirement to provide drive across the pipe entry slot as its entrance rotates passed the drive means.
The drive means may be formed to provide continuous drive by being in continuous driving engagement with the body.
In order to provide drive to that part of the cutting member body comprising the pipe entry slot the drive means may be adapted to apply drive to the wall of the pipe entry slot. Drive is thereby not temporarily lost when the slot rotates passed the drive means.
The drive means may include an operative portion adapted to engage the pipe entry slot wall and to apply drive thereto.
The drive means may include an operative portion which is formed so as drivingly to engage the pipe entry slot as the slot rotates. In this way when the slot passes over the drive means drive to the body is not interrupted.
The operative portion may comprise a projection, such as a cam, tooth, detent or the like. The operative portion may therefore be formed so as to enter the slot and engage the slot wall to provide drive to the body.
The cutting member may have a drive surface for receiving drive from the drive means.
At least part of the drive surface may form part of the body. For example teeth or other projections for receiving drive may be cut into or formed on the body.
Alternatively or additionally at least part of the drive surface may be formed separate from and be attachable to the body. For example, a jacket-like or strap-like member could be provided for attachment to the body to provide a drive surface. Accordingly an existing cutting member could be retrofitted with a drive surface and the cutting member body requires no modifications.
The wall of the pipe entry slot may form part of the drive surface.
The drive means may be provided on a rotatable drive member. The drive member can therefore itself be driven to rotate and this rotation can be transferred, in the form of counter-rotation, to the cutting member by the drive means. A system of counter-rotating wheel-like members is mechanically simple and easy to manufacture.
In order that the operative portion of the drive means engages the slot at the same point along its rotational path on every rotation it is important that the cutting member and drive member do not slip relative to each other.
Accordingly the device may be formed so that the relative rotational positions of the cutting member and the drive member can be controlled and precisely determined so that the operative portion of the drive means aligns with the slot each time it rotates relative to the cutting member.
The cutting member and the drive member may be formed as co-operating cog wheels. Accordingly the drive means include the teeth of the drive member cog wheel which engage co-operating teeth on the cutting member body to transfer rotation. Alternatively, the drive member may transmit rotation to the cutting member at least partly by frictional engagement. Accordingly the drive member and/or the cutting member may be formed from or coated with a material having a high coefficient of friction so that rotation can be transferred.
The device may include a housing within which the cutting member is rotatable, and the drive means may also be provided in the housing so that the cutting member and the drive member can be placed and held in a required relative rotational position and the device can be supplied as a single unit.
The device may be motor-driven. Motive power may be provided by any convenient means such as a rotary motor.
The drive means may be motor-driven. The motor for powering the drive means may be formed as part of the device or may be provided by an external source, with the device adapted to receive drive from that external source.
The drive means may include a drive shaft which is engageable either by a motor formed as part of the device or engageable by an external drive source. For example, the device may include a drive shaft which is engageable by a power tool such as a drill in which rotation of the drill head can be transferred first to the drive shaft and then to the drive means for transfer to the cutting member body. It should be understood, that in an alternative embodiment such a drill may be used as and understood as an electric motor to drive the drive means. Thus the use of the descriptive phrase “drill” is not limiting to an particular hand drill, or stationary drill but should be broadly understood as an electric motor.
The cutting member body may be engaged at a single point by the drive means to provide rotation. By engaging the cutting member body only at a single point the complexity of the drive means can be reduced compared to a system involving multiple points of contact.
Accordingly, substantially uninterrupted drive causing the cutting member to rotate can be provided by the drive mechanism. Powered drive is therefore provided even as the entrance to the slot rotates passed the drive means.
The drive means may be adapted to provide drive in the absence of direct physical engagement. In this way the problem of engagement over the slot is overcome.
The drive means may comprise magnetic means for generating one or more magnetic fields and the cutting member may include means responsive to each magnetic field to cause the cutting member to rotate.
For example the cutting member may be provided with one or more magnetic elements around its periphery and the drive means comprises a series of electro-magnets which can be selectively energised. By selectively energising and de-energising the electro-magnets the magnetic elements could be attracted in a sequence which causes the cutting member to rotate without requiring any physical contact.
A further possibility to overcome the problem of drive over the slot is to form the cutting member as a flywheel so that sufficient kinetic energy, or a means for imparting sufficient kinetic energy, could be imparted to the member to allow the slot to pass drive means which operate by direct physical engagement, without causing loss of rotation.
The above and other objects, features and advantages of the present invention will become apparent from the following description read in conduction with the accompanying drawings, in which like reference numerals designate the same elements.
The present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which:
Reference will now be made in detail to several embodiments of the invention that are illustrated in the accompanying drawings. Wherever possible, same or similar reference numerals are used in the drawings and the description to refer to the same or like parts or steps. The drawings are in simplified form and are not to precise scale. For purposes of convenience and clarity only, directional terms, such as top, bottom, up, down, over, above, front, back, and below may be used with respect to the drawings. These and similar directional terms should not be construed to limit the scope of the invention in any manner. The words “connect,” “couple,” and similar terms with their inflectional morphemes do not necessarily denote direct and immediate connections, but also include connections through mediate elements or devices.
Referring now to
Referring first to
The surface of the drive member 15 is smoothly curved with the exception of a tooth 25 which projects at a specified point on the circumference of the member 15 relative to the slot of the member 10. The tooth 25 includes a ramped surface 26 and an inclined surface 27.
As the members 10, 15 rotate relative to each other eventually the slot 13 of the cutting member 10 rotates to the point at which the slot 13 starts to rotate passed the driving member 15. Accordingly the exterior surfaces of the members 10, 15 are no longer in direct rolling contact and an alternative way of transferring drive must be provided. The profile and the positioning of the tooth 25 is such that as the slot 13 approaches the driving member 15 the ramped face 26 of the tooth 25 enters the slot 13 and engages the slot wall 14a so that the driving member 15 can continue to transfer rotation to the cutting member 10.
In
In
The diameters of the cutting member 10 and the drive member 15 are substantially the same, although this is not required in alternative embodiments as will be later described. In addition, the circumferential extent of the tooth 25 is substantially the same as the slot 13 (as shown best in
In other embodiments (not shown) the reverse driving arrangement is provided in which the drive member 15 has a recess into which the slot wall 14a passes. The wall is then engaged by the recess wall to provide drive.
Referring now to
Referring now to
While in theory the members 210, 215 could be provided separately and brought together at the point of use, it may be preferable for them to be more permanently associated, for example to allow their relative positions to be fixed. In this embodiment the members 210, 215 are provided in a housing 230 which is in section generally in the shape of the number eight in outline and together they form a hand-held cutting device generally indicated 250. The cutting member 210 is rotatably supported in the housing 230 by any convenient means such as rollers (not shown) or the like. The housing 230 includes an opening 235 and the slot 213 of the cutting member 210 can be aligned with the opening 235 so that a pipe (not shown) can be introduced through the opening 235 and into the slot. In some embodiments (not shown) the device includes the facility to ensure that the slot 213 and opening 235 are always aligned when the device 250 is not in use so that the device is always ready to receive a pipe. Following insertion of a pipe the mode of operation of the device is as described in relation to
Referring now to
Referring now also to
Because the device of
Referring now to
The leg 431 accommodates a rotary motor 432 connected to the drive shaft 420, and a battery 433 for powering the motor 432. Battery 433 should be understood by those of skill in the art to be readily adaptable as a replaceable or rechargeable battery enabling continuous operation. Alternatively, battery 433 may be replaced by an electric supply cord (not shown) to drive rotary motor 432 in a manner understood by those of skill in the art of designing powered tool mechanism. As an additional benefit, conveniently the leg 431 forms a handle by which the device can be manipulated.
In use the motor 432 rotates the shaft 420 and the operation of the device is then as described in relation to
In this embodiment therefore the device includes an integral power source and motor for providing drive.
Referring now to
The cutting member 510 has a magnetic element 565 embedded in its surface at a point on its periphery.
The housing 530 is provided with five electro-magnets 570a-e spaced around its interior. The electro-magnets 570a-e can be selectively energised and de-energized by a power supply 575 and switching means 580. The electro-magnets 570a-e can be energized to cause the magnetic element 565 to be variously attracted or repelled and consequently rotate the member 510. By energizing and de-energizing the magnets 570a-e in sequence the member 510 can be continuously rotated without physical engagement. This drive mechanism could be used to rotate the member 510 in either direction by changing the sequence of energizing and de-energizing the electro-magnets 570a-e.
In yet another alternative embodiment of the present invention, electro-magnets 570a-e are removed, and rollers 560 receive a driving force. In such an embodiment, as at least two rollers 560 contact cutting member 510 through out a rotation cycle, rotating power provided continuously vi rollers 560 will smoothly rotate a cutting member without the cost of an electromagnetic assign.
Referring now to
The drive surface 690 comprises a rubber sheet 691 formed with a plurality of teeth 692 extending transverse its length.
The surface 690 is sized so that it can be wrapped around the curved exterior of the member 610 to form a drive jacket. The drive surface 690 can then serve to receive drive force from a drive member 115 of the type shown in
Since the sheet 691 is formed from rubber, or other another high molecular weight elastomeric material, it has a high coefficient of friction and relative slippage between the sheet and the member 610 is prevented.
The surface 690 may be permanently secured to the body, such as by adhesion or welding, or temporarily attaching so as to be removably-attached.
Those of skill in the art should recognize, that as used herein for the preferred embodiment, the pipe cutting members possess a cylindraceous outer boundary in which the slot penetrates the outer boundary thereof. The descriptive phrase cylindraceous shall be understood as descriptive language referring to a body that has a generally curved outer boundary, and includes elliptical, ovoid, uniform and non-uniform curved boundary forms. Nothing herein should limit the understanding of those skilled in the art of pipe cutting members or drive devices to a uniform shape or continuous or uniform outer boundary, nor shall anything herein require the pipe cutting member to be a geometrically uniform cylinder along its length.
In the claims, means- or step-plus-function clauses are intended to cover the structures described or suggested herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, for example, although a nail, a screw, and a bolt may not be structural equivalents in that a nail relies on friction between a wooden part and a cylindrical surface, a screw's helical surface positively engages the wooden part, and a bolt's head and nut compress opposite sides of a wooden part, in the environment of fastening wooden parts, a nail, a screw, and a bolt may be readily understood by those skilled in the art as equivalent structures.
Having described at least one of the preferred embodiments of the present invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes, modifications, and adaptations may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.
Number | Date | Country | Kind |
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GB0423469.6 | Oct 2004 | GB | national |