GB2239208A - Flange cutter - Google Patents

Abstract

A flange cutter, particularly for forming holes of desired size in stoma adhesive seals previously given an undersized starter hole comprises a base 9 having an upstanding central cylindrical portion 13 carrying external screw-threading 14 thereon and formed with a longitudinal surface slot 15 extending from one end thereof over a portion of the length. A die element comprises an upper handling portion such as a wheel 16 and a lower die cutting element 18 mounted to be freely rotatable with respect to the handling portion. The wheel 16 and die cutting element 18 have axial passages therethrough of like diameter with a member 28 projecting from a coupling element 23 extending into the passage in the die cutting element. Rotational engagement of the wheel 16 with the central cylindrical portion 13 causes the die cutting element 18 to travel linearly with respect to the central cylindrical portion to punch the required hole which may be non-circular, in the flange. In an alternative embodiment the seal support 11 is associated with a floating bush (31, Fig 7) to assist in removing the waste. <IMAGE>

Description

FLANGE CUTTER This invention relates to flange cutters and in particular but not exclusively to a stoma adhesive seal hole cutter for emplacement on the body around a stoma and attachment of a flexible waterproof bag thereto.

As a result of illness and attendant surgery, it is necessary for many people to evacuate matter from the intestine or bladder through a stoma into a flexible waterproof bag fixed thereover. The mounting of the receptacle is generally effected via a flange which is placed over and around the stoma to adhere to the body and which is formed with a coupling ring over which the receptacle is fitted with the aim of achieving as reliable a fit as possible thereby to avoid seepage.

Seepage will also occur as a result of unsatisfactory provision of the flange itself. Adhesion to the skin should be as intimate as possible and generally requires, if appropriate, regular shaving of the skin. Moreover, the flange must have an opening corresponding in shape and size to that of the stoma so that all matter will pass directly into the flexible bag. Stomas may vary considerably in size and are often irregular. Stoma flanges are generally made in a range of sizes according to the intended range of sizes of stoma with which they can be used. The flange itself is generally always the same size but flanges differ according to the diameter of coupling ring with the maximum size of stoma for which a particular flange may be used being several millimetres smaller than the coupling ring diameter or the appropriate flange size.Thus a 32 mm flange can be used for stomas up to 28 mm, a 38 mm flange can be used for stomas up to 35 mm etc. The coupling ring itself is formed on a soft plastics disc to which flange it self adheres. This plastics material of the flange is relatively thin and it is necessary for the patient to have an aperture formed in the disc of appropriate size which is matched to the shape and size of his stoma.

This is generally carried out by cutting by use of scissors or even by use of a suitably sharp knife blade.

However such cutting is difficult to carry out accurately, particularly because many patients are elderly and have poor eyesight or lack the control to cut accurately a relatively small sized opening.

It is for this reason that there have become available in recent years devices designed to assist the patient needing to tailor a stoma flange to his own stoma. One such device which is described in GB-A2155839 is a simple die cutter having a steel body or shank on one end of which there is hardened cutting edge which is guided into the required cutting position on the flange by a shoulder on the shank. This device requires the exertion of substantial pressure while twisting in achieving a satisfactory cut and is likely to prove to be beyond the skill of many elderly persons. Moreover its use is limited to the production of circular openings of one set diameter.

Other devices which might conceivably be used as such or when modified for the production of stoma holes in the plastics discs of stoma flanges are generally of the hand punching type such as described in GB-A-620272 or the rotary cutter type as described in GB-A-618008 and GB-A-499300. These are generally relatively complicated devices which are restricted to the production of one size of hole of generally circular form. Moreover such devices are not specifically designed for use in the production of openings in stoma flanges where it is necessary to cut particularly soft plastics material which will readily adhere to cutting edges and surfaces.

It is an object of this invention to provide a flange cutter whose operating and construction principle is appropriate to the cutting of both circular and irregularly shaped openings.

According to the present invention, there is provided a punch and die flange cutter comprising a base having an upstanding central cylindrical portion carrying external screw-threading thereon and formed with a longitudinal surface slot extending from one end thereof over a portion of the length thereof, and a die element comprising an upper handling portion and a lower die cutting element mounted to be freely rotatable with respect to the handling portion, the handling portion and die cutting element having axial passages therethrough of like diameter with a projecting member extending into the passage in the die cutting element and the handling portion having, in said passage therein, internal screwthreading matched to said external screw-threading, said projection being matched in size to said longitudinal surface slot for travel therealong.

With a cutter embodying this invention, although the die cutting element is freely rotatable with respect to the handling portion, it is the handling portion which is rotated over the central cylindrical portion of the base as its internal screw thread engages the screw thread on the latter and drives the die cutting element downwardly with linear displacement only of the latter until it engages the flange in which a cut is to be made.

Rotation of the die cutting element is to be avoided since punch and die cutting is a pressure cut and any movement of the cutting element will cause tearing of the flange to be cut. Such movement is prevented simply by engagement of the projection in the slot on the central cylindrical portion of the base. The cutting die may be formed with a suitable cutting edge to enhance the precision of cut achieved in the flange. Because there is no rotation of the die cutting element, the cutting die can be of any arbitrary shape and can be tailored to the shape of an irregular stoma possessed by a patient.

Whereas punch and die cutters are conventionally relatively heavy hand implements, since it is necessary for them to be held steadily over the surface at which a cut is to be made by the person wishing to make the cut, and indeed are generally cast metal objects, because of the manner in which the cutting die is driven downwardly with the device of this invention, the die cutting element and indeed all or most component elements of the device of this invention can be formed of injection moulded plastics material, such as high impact polystyrene thereby being both lighter and cheaper.

A preferred form of cutter embodying this invention is one wherein the base comprises a recess defining central portion, the recess being matched in shape and dimension to the die cutting element to receive the same during cutting of a flange.

Such a cutter may then be modified to assist in removal of waste when the base of the recess is provided by the upper surface of a floating bush carried by the base and capable of reciprocal movement with respect thereto.

For a better understanding of the invention and to show how the same can be carried into effect, reference will now be made by way of example only to the accompanying drawings wherein: FIGURE 1 is a perspective view of a stoma flange as supplied by its manufacturer; FIGURE 2 is an elevational view of one form of flange cutter embodying this invention; FIGURE 3 is an exploded view of the flange cutter of Figure 2; FIGURE 4 is a section through the die cutter of Figure 2 taken at IV-IV; FIGURE 5 is a perspective view from below of an alternative cutting die to that shown in Figures 2 to 4; FIGURE 6 is an elevation view of a modified flange cutter base; and FIGURE 7 is a section through the flange cutter base of FIGURE 6.

Referring to Figure 1, a typical proprietary stoma flange comprises a soft plastics disc 1 conventionally formed with a central opening 2 and having a flat base coated with adhesive and covered with a protective covering member 3 which is stripped away just before the flange is applied to the skin. Set in the opposite surface of the disc away from the outer periphery thereof is an annular coupling ring 4 whose outer periphery is shaped to enable a flexible waterproof bag (not shown) to be held thereon. Adhering to the upper surface of the disc and extending a considerable distance beyond the confines thereof is a flange 5 itself formed of a flexible dressing material and backed with a strippable protective layer 6 whose removal is assisted by the provision of cuts 7 therealong.In use, an opening sized to match that of a stoma will be cut in a central area of the disc surrounding the opening 2 and, after removal of protective coverings on the flange and disc will be applied to the stoma with the opening slightly larger (by say 3 mm) than and surrounding the stoma to accommodate eventual shrinking of the opening and the flange and disc will be pressed to the skin to adhere thereto ready for fixing the flexible waterproof bag to the coupling ring 4.

Turning next to Figures 2 to 4, the stoma cutter comprises a base 9 comprising a circular central recess 10 in which is a fixed a circular disc support 11 shown to be of two part formation but which can be a single element and whose outer diameter is matched to the size of stoma flange disc which is to be worked upon and through the centre of which projects an upstanding cylindrical portion 13 which is externally screw-threaded in a central region 14 and which is formed with a longitudinal slot 15 extending from the top to a position below the screw-threading.The central part of disc support 11 defines an annular channel lla having a base llb. The screw-threading in the region 14 matches internal screw-threading in a handling portion 16 of a punch and die cutter 17 which is separable from the cylindrical portion 13 to allow placing of a stoma flange of the type shown in Figure 1 either way up on the base 9. The handling portion is essentially a handwheel carrying a die cutting element 18 which is freely rotatable with respect to the handwheel to which it is attached via a coupling arrangement and whose external diameter is less than the diameter of annular channel lia. The coupling arrangement comprises a flat ring 19 having bosses 20 entering into matching bores 21 in the underside of the handling portion.The underside of the handling portion is formed with a recess 22 of cylindrical form surrounded by a raised portion in which the bores 21 are formed. Trapped between the ring 19 and the underside of the die cutting element is a coupling element 23 of low cylindrical form having a peripheral flange 24 at one end which is sized to match the diameter of the recess 22. On the opposite end face 25 of the coupling element are formed bores 26 by means of which a die cutter 27 is attached thereto. The coupling element 23 is formed with a projection 28 extending lengthwise thereof in its interior and sized to match the slot 15 found in the handling portion 16. A single continuous passage 29 of uniform diameter extends through handwheel 16, coupling element 23 and die cutter 17. The die cutter itself is formed with a cutting edge 30 of circular form.

In constructing the punch and die cutter 17, the cutting element 18 and coupling element 23 are to be secured together. Initially, however, the coupling element 23 is placed in the recess 22 in the underside of the die cutting element 18 and held captive therein by means of the flat ring 19 whose mounting is assisted by introduction of a tiny amount of glue into each of the bores 21. The cutting element 18 is then secured to the coupling element 23 to provide a combination which is freely rotatable with respect to the handling portion 16.

When carrying out a cutting operation utilising the flange cutter of Figures 2 to 4, it is simply necessary to push the handwheel 16 onto the cylindrical portion 14 of the base until the internal screw-threading in the handwheel 16 is able to engage with screw-threading on the cylindrical portion 13. This will have required the projection 28 extending into the internal passage 29 of the coupling element 23 to have engaged the slot 15.

Continued descent of the handwheel 16 requires rotation thereof while the die cutter 17 is constrained against rotation by virtue of the engagement of projection 28 and slot 15 and continues to descend in a straight line until the cutting element 18 engages with the disc of the stoma flange in which a cut of prescribed size determined by the diameter of the cutting edge 30 is to be produced.

The cutting edge of cutting element 18 is forced through the flange to enter annular recess la in the base 9 to achieve the desired cut merely by continued rotation of the handling portion 16. The force required to rotate the handwheel is converted into a particularly effective linearly directed force for achieving the desired cut.

Since the cutting edge does not undergo any motion other than linear, it is possible for the cutting edge to be of any desired shape and hence as shown in Figure 5 the cutting edge can be non-circular according to the shape of an irregular stoma with which the flange is to be used. With either of the illustrated cutting edges, the cutting edge may be chamfered or bevelled as a result of which the resulting shearing assists in producing the desired cut. It is not essential if the cutting achieved by means of the cutting edge does not act efficiently on the protective covering member 3 on the stoma flange since this will in any case be peeled away.

Withdrawal of the cutting element 18 from the annular recess lla is achieved simply by rotating the handwheel 16 in the opposite direction to achieve linear upward motion of the die cutter. Once the handwheel is out of engagement with the cylindrical portion 13 of the base, the flange can readily be removed from the latter and is ready for use. The cut out annulus of flange material will lie within the annular recess lla and may be awkward to remove owing to its tight fit therein. To avoid this difficulty, Figures 6 and 4 provide a modified base 9 in which the fixed circular disc support 11 is modified and provided with a floating bush 31.The bush 31 fits around the lowermost part 33 of central cylindrical portion 13 which widens out into a circular region 34 which is secured by means of adhesive to base 9 and has its upper surface below the level of the upper surface of base 9 thereby forming a shallow annular channel surrounding the cylindrical portion 13. The circular disc support 11 is so shaped as to provide a wide annular cavity 32 between it and the upper surface of the base 9. The bush 31 comprises a pair of discs 35 and 36 connected by diametrically opposed spacer elements 37 able to travel in slots 38 in base 9 the upper disc 35 is sized so that, when the bush 31 is its lowermost position, it lies in the shallow annular recess existing on top of circular region 34.When the cylindrical portion 13 is not fully engaged with the handling portion 16, the bush 31 is capable of free movement up and down with respect to the base 9 and the upper surface of disc 35 provides base 10b of annular recess lla. Disc 35 is oversized with respect to recess 11 thereby limiting the upward travel of the push-out element 31.

When a cutter with the modified base of Figures 6 and 7 is operated, with cutting taking place in the same manner as described with respect to Figures 2 to 4, screwing down of the handwheel 16 will eventually force the cutting element 18 into recess 11. As it cuts through the flange, the cutting element 18 will act on the upper surface of disc 35 to act on the bush 31 and hold it firm as the cut is completed. On withdrawal of the cutting element 18 from recess 11, bush 31 recovers its freedom to float and once the handwheel 16 has been removed from engagement with upstanding cylindrical portion 13 and the flange removed from the base, pushing up of the bush 31 from its underside (disc 36) will loosen the annulus of cut out flange material in the recess 11 and allow it to be removed readily by hand.

Claims (8)

CLAIMS:

1. A punch and die flange cutter comprising a base having an upstanding central cylindrical portion carrying external screw-threading thereon and formed with a longitudinal surface slot extending from one end thereof over a portion of the length thereof, and a die element comprising an upper handling portion and a lower die cutting element mounted to be freely rotatable with respect to the handling portion, the handling portion and die cutting element having axial passages therethrough of like diameter with a projecting member extending into the passage in the die cutting element and the handling portion having, in said passage therein, internal screwthreading matched to said external screw-threading, said projection being matched in size to said longitudinal surface slot for travel therealong.

2. A cutter according to claim 1 which is formed entirely of injection moulded plastics material.

3. A cutter as claimed in Claim 2 which is formed entirely of high impact polystyrene.

4. A cutter as claimed in any preceding claim, wherein the die cutting element is circular.

5. A cutter as claimed in any one of claims 1 to 3, wherein the cutter is irregularly shaped.

6. A cutter as claimed in any preceding claim wherein the base comprises a recess defining central portion, the recess being matched in shape and dimension to the die cutting element to receive the same during cutting of a flange.

7. A cutter as claimed in claim 6, wherein the base of the recess is provided by the upper surface of a floating bush carried by the base and capable of reciprocal movement with respect thereto.

8. A punch and die flange cutter, substantially as hereinbefore described with reference to Figures 2 to 5 of the accompanying drawings optionally modified by Figures 6 and 7.