MX2009000129A - Cuttings removal wipers for cutter assemblies and method. - Google Patents

Abstract

A wiper may be supported on at least one of a radially inwardly or radially outwardly facing dynamic interface surfaces of a pair surfaces on respective cutter journal and cutter shell. The wiper may be in the form of a low profile lug having a leading edge generally diagonally oriented relative to an axis of rotation of the cutter shell on the cutter journal. Thus, the leading edge of the wiper will move formation particles axially out from between the cutter journal and the cutter shell and away from a bearing seal. The wiper may have a height less than a regular clearance between the journal and the shell. A plurality of wipers may be supported on the dynamic interface surface of either the shell or the journal and may extend into close proximity to the oppositely facing dynamic interface surface of the other of the shell or the journal.

Description

CLEANERS FOR THE REMOVAL OF CUTS FOR CUTTING ASSEMBLIES AND METHOD TECHNICAL FIELD This invention relates generally to cutter assemblies that include mechanisms to exclude or keep debris and other particles formed away from the bearings of the assemblies during ground drilling.

BACKGROUND OF THE INVENTION Cutting assemblies for ground boring have cutter heads with cutting shells that are rotatably supported in sleeves for rotation during drilling operations. Due to the abrasive environment on the face of a rock that is being drilled and the confined volume in which the cuttings and other debris are contained in close proximity to the cutting heads, the entry of the cuttings and debris into the bearings of the Cutting heads has been a problem that many have tried to address in a variety of ways. In some cases, seals including washers and / or other annular seals have been incorporated to form a barrier between an interior and an exterior of the cutting heads. The bearings are held between the bearing surfaces in respective cutting envelopes and sleeves of the cutting heads in an interior of the cutting heads and are protected from the abrasive environment on an exterior by the seals. However, cuts and debris still tend to enter the seals and reduce the rotational movement that these seals must allow. Cuts and debris can also damage or interfere with the seals so that cuts and debris can enter the bearing heads of the cutter heads and inhibit rotational movement and / or damage the bearings. In a specific example, a seal for a replaceable cutter that is used in the elevated drilling industry can typically be a mechanical face seal. As used in this industry, the mechanical face seal is incorporated to seal the bearing lubricant and exclude particle formation, which may include cuts and other debris. The face seal assembly is comprised of two metal annular seals and two washers that form two sets of an annular seal and a washer. The seal assemblies are assembled one against the other, with the two annular seals each having a very flat dynamic seal surface. The washer provides and maintains a preload on the annular seal. However, it has been found that the contaminants produced during the operation are packaged within the area adjacent to the annular seals and have the net effect of reducing seal life.

BRIEF DESCRIPTION OF THE INVENTION There is a need for a device to sweep cuts and other debris away from the seals and bearings of the cutter assemblies. The present invention relates generally to cutter assemblies that include mechanisms for the removal of debris during ground drilling. More specifically, the present invention is a cutter assembly for elevated drilling and other applications in which the cutter assembly has cleaners on dynamic interface surfaces that face radially to sweep cutouts away from the seals and bearings of the assembly during drilling. Earth. In a simple form, one embodiment of the present invention may include a replaceable cutter assembly having a sleeve with at least one sleeve bearing surface and at least one dynamic sleeve interface surface facing radially outward. The cutting assembly may also have a cutting envelope rotatably supported on the sleeve. The cutting envelope may have a cutting envelope bearing surface and at least one dynamic cutting envelope interface surface facing radially inward. The cutter assembly may further include at least one cleaner on the at least one interface surface of one of the sleeve and the cutting shell. The at least one cleaner it can then be close to and face the at least one interface surface of the other of the sleeve and the cutting shell. The cleaner can be a low profile tab formed integrally in one of the sleeve and the cutting shell. A rotational axis of the cutting envelope in the sleeve defines an axial direction. The cleaner may have an edge that extends generally diagonally relative to the axial direction. Alternatively, the cleaner may have an edge that extends generally helically relative to the axial direction. The replaceable cutter assembly may have a plurality of cleaners that include the at least one cleaner. The cleaners may protrude radially from the at least one of the interface surfaces. The plurality of cleaners may include four permanent low profile lugs circumferentially spaced apart from each other on the at least one of the dynamic sleeve interface surfaces relative to the axis of rotation. The permanent low profile lugs may have other edges that extend generally diagonally relative to the axial direction. The replaceable cutter assembly may further include at least one seal in sealing contact with the cutter housing and the cutter sleeve between the dynamic interface surfaces of the cutter housing and the cutter sleeve on one axial side and the cutter surfaces. bearing of the cutting envelope and the cutting sleeve on another axial side of at least one seal. The replaceable cutter assembly can include a plurality of dynamic sleeve interface faces that face radially outwardly including the at least one dynamic sleeve interface surface facing radially outward. The replaceable cutter assembly can also include a plurality of dynamic cutting envelope interface surfaces that face radially inwardly including the at least one dynamic cutting envelope interface surface facing radially inwardly. The plurality of dynamic cutting envelope interface surfaces facing radially inward can form respective pairs of interfacing surfaces with the plurality of dynamic sleeve interface surfaces facing radially outward. The assembly may have at least one of the cleaners on at least one of the interface surfaces of each of the interface surface pairs. Each of the at least one cleaner can be close to and face another surface and interface of each of the pairs of interface surfaces. It is considered that the present invention has patentable elements that are not limited to the complete assembly. As an example, the invention may encompass a replaceable cutter sleeve which may include a sleeve having at least one sleeve bearing surface and at least one dynamic sleeve interface surface facing radially outward. The cutter sleeve may have at least one cleaner on the at least one interface surface. The dynamic sleeve interface surface facing radially outward can have at least a first portion with a first diameter. The dynamic sleeve interface surface facing radially outward can have at least a second raised portion with a second diameter larger than the first diameter. The first and second portions may extend along a common circumferential line. In the replaceable cutter sleeve, a rotational axis of the sleeve can define an axial direction. The dynamic sleeve interface surface facing radially outward may extend circumferentially and may be spaced proximally relative to the sleeve bearing surface in the axial direction. The cleaner may have an edge that extends generally diagonally relative to the axial direction. The replaceable cutter sleeve may have a plurality of cleaners that include the at least one cleaner. The wipers can form second portions of the dynamic sleeve interface surface facing radially outward. The cleaners may protrude radially from the first portions of the at least one interface surface. The plurality of cleaners may include four permanent low profile lugs spaced apart from each other on the dynamic sleeve interface surface with relation to the axis of rotation. The permanent low profile lugs may have edges that extend generally diagonally relative to the axial direction. The at least one second portion of the dynamic sleeve interface surface facing radially outward may include the at least one cleaner formed integrally as a part with the first portion of the dynamic sleeve interface surface facing radially. outside. The dynamic sleeve interface surface may be in a detachable part removably attached to the sleeve. The separable piece may have a seal retainer. The replaceable cutter sleeve can include a plurality of dynamic sleeve interface faces facing radially outward that include the at least one dynamic sleeve interface surface facing radially outward. Each of the dynamic sleeve interface faces facing radially outwardly may be in a detachable part removably attached to the rest of the sleeve. In another aspect or embodiment, the present invention may encompass a replaceable cutting shell having at least one cutting envelope rolling surface and at least one dynamic cutting envelope interface surface facing radially inwardly. The replaceable cutting envelope can also include at least one cleaner in the at least one interface surface. The dynamic cutting envelope interface surface facing radially inward can have at least a first portion having a first diameter and at least a second raised portion having a second diameter smaller than the first diameter. The first and second portions may extend along a common circumferential line. An axis of rotation of the cutting envelope can define an axial direction. The dynamic sleeve interface surface facing radially inward may extend circumferentially and may be spaced proximally relative to the bearing surface of the cutting shell in the axial direction. The cleaner may have an edge that extends generally diagonally relative to the axial direction. The replaceable cutting envelope may include a plurality of cleaners that include the at least one cleaner. The wipers can form second portions of the dynamic cutting envelope interface surface facing radially inward. The cleaners may protrude radially from the first portions of the at least one interface surface. The plurality of cleaners may include four permanent low profile lugs circumferentially spaced apart from one another on the dynamic cutting envelope interface surface relative to the axis of rotation. The Permanent low profile lugs may have edges that extend generally diagonally relative to the axial direction. At least a second portion of the dynamic sleeve interface surface facing radially inward may include the at least one cleaner formed integrally as a part with the first portion of the dynamic sleeve interface surface facing radially toward in. In another aspect of the invention, a separate part may be removably attached to at least one of the cutter assembly sleeve or to a cutting shell of the cutter assembly. The separate piece may include a radially facing dynamic interface surface which may have at least a first portion and a second portion. The first and second portions may have respective first and second diameters different from each other. The first and second portions may extend along a common circumferential line. At least one of the first and second portions can form low profile lugs relative to each other of the first and second portions. The separate piece may have a joining structure for removably attaching the piece to at least one of the cutter assembly sleeve and the cutting shell of the cutter assembly. The separate part may include a seal retainer with a seal retainer structure. In another aspect, the present invention can include a method for inhibiting the entry of debris into a cutter assembly. He The method may include sweeping a first dynamic interface surface facing radially with at least one cleaner disposed on a second dynamic interface surface facing radially in opposite manner. The method can also include the displacement of debris axially away from the at least one seal and at least one bearing of the cutter assembly. The sweep and displacement steps may include automatic sweep and displacement during normal rotation of a cutting envelope of the cutter assembly relative to a cutter sleeve of the cutter assembly. The steps of sweeping and displacement may include presenting a leading edge of at least one cleaner transverse to an axial direction defined by an axis of rotation of the cutting envelope relative to the cutting sleeve. The sweep and displacement steps may include displacing the leading edge of at least one wiper circumferentially along the second dynamic interface surface that faces radially in opposite manner. The method may include sweeping a plurality of dynamic interface surfaces that face radially including the first dynamic interface surface that faces radially with a plurality of cleaners that include the at least one cleaner. The plurality of cleaners may be arranged on a plurality of dynamic interface surfaces that face each other in an opposite manner, including the second dynamic interface surface facing radially in an opposite manner. The method may include displacing debris axially away from a plurality of seals including the at least one seal and displacing the debris axially away from a plurality of bearings including the at least one bearing of the cutter assembly. The steps of sweeping and displacement may include automatic sweeping and shifting during normal rotation of the cutting envelope of the cutter assembly relative to the cutter sleeve of the cutter assembly. The above and other features and advantages of the present invention will become apparent from the following more detailed description of the particular embodiments of the invention, as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a perspective view of a sleeve having cleaners according to an embodiment of the present invention; FIG. 1 B is a sectional view in a central plane coincident with an axis of rotation of a cutter assembly including a sleeve similar to the sleeve of Figure 1A according to an embodiment of the present invention; FIG. 2 is a partial sectional view similar to that of the Figure 1 B showing a side view of the sleeve having cleaners according to an embodiment of the present invention; FIG. 3 is a detailed view of an area III of Figure 1 B showing details of an alternative embodiment according to the present invention; and FIG. 4 is a detailed view of an area IV of Figure 1 B showing details of an alternative embodiment according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION As mentioned above, the embodiments of the present invention generally refer to cutter assemblies that include mechanisms to exclude debris during ground drilling. Seals of a variety of types and configurations are known. For example, U.S. Patent No. 5,984,024 to Strand, is hereby incorporated by reference as an example of an elevated drilling cutter assembly using a mechanical seal. US Patent No. 6,033,117 to Cariveau et al. Is also incorporated herein by reference because it includes a wide variety of seal configurations that may be additionally or alternatively incorporated in conjunction with various cutting assemblies. While the present invention may be particularly useful in high drilling applications due to the relatively smaller amount of fluids used in the cleaning and removal of cuttings, it will be understood that teachings of this invention can be applied in the same way to other earth drilling applications that include those that incorporate pressurized fluids in the cleaning and removal of the cuttings. Figure 1A is a perspective view of a sleeve 2 for a cutter assembly 3, (shown in Figure 1 B and 2), for earth drilling applications. The sleeve 12 can have wipers 15 in the form of low profile lugs or raised portions in a first dynamic sleeve interface surface facing radially outwardly 18. The dynamic sleeve interface surface 18 can have at least a first portion 21 and at least a second portion 24. The sleeve 12 has one or more bearing surfaces 27, 30, 33, and a second dynamic sleeve interface surface facing radially outwardly 36. The second interface surface of dynamic sleeve facing radially outwardly 36 may have wipers 39, in at least a first portion 42, and at least a second portion 45 similar to the first dynamic sleeve interface surface facing radially outwardly 18. The sleeve 12 can be supported together with the remainder of cutter assembly 13 in an assembly. U.S. Patent No. 5,984,024 to Strand shows and describes a number of setup configurations. As shown in the sectional view of Figure 1 B, the cleaners 15, 39 may be disposed in the cutter sleeve 12, as shown in Figure 1A, or alternatively in a cutting envelope. 16, as shown in dashed lines in Figure 1B. The wipers 15, 39 are in the form of low profile lugs which are angled relative to an axis of rotation and central axis 48 of a cutter head housing 16 and cutter sleeve 12, respectively. The low profile lugs or cleaners 15, 39 are shown on the dynamic interface surfaces 18, 36 between the cutting shell of the cutting head 16 and the cutter sleeve 12 and may be integral with any of the cutting sleeves 12. Alternatively, the low profile lugs or cleaners 15, 39 may be on a dynamic interface surface facing opposite the cutting shell 16. The low profile lugs or wipers 15, 39 are located outside and adjacent to the respective seals 51, 54 of the cutting envelope 16. The lugs or cleaners 15, 39 are angled so that the relative movement between the cutter sleeve 15 and the cutter housing 16 axially sweeps the debris out of the intermediate part between the sleeve 15 and the envelope 16. The lugs or cleaners 5, 39 are oriented to displace the formation of particles including cut-outs and other debris axially in the distance. of the seal as the cutting wrapper 16 rotates relative to the cutter sleeve 15 during use. In this way, the cleaners 15, 39 can also move the waste away from one or more bearings 57, 58, 59 and respective bearing surfaces 27, 30, 33, 61, 62, 63 in an interior of the cutter assembly 13.

As can be seen from the partial sectional view of Figure 2, a wiper 15, 39 can be formed on a dynamic interface surface 18, 36 of the sleeve 12 between a stationary component (sleeve 12) and a rotating component (housing) cutter 16). The cleaner 15, 39 is angled from the axis of rotation 48 of the two components in such a way that when the cutting shell is rotating in the normal "drilling" direction shown by the arrow 66 in Figure 2, the formation of particles that It includes cuts and other debris being swept out of the dynamic interface. The removal of debris from the dynamic interface in this manner maintains the area adjacent to the cutter seals 51, 54 much cleaner and provides an extended life for the seal. The cleaner (s) can be formed by welding, machining, or other suitable methods. The wipers 15 have leading edges 69 and the wipers 39 have leading edges 72 which confront the formation of particles that are brought into contact therewith at least in part by the cutting envelope and force them out of the intermediate part between the sleeve cutter 15 and cutter housing 16 in opposite directions as shown by arrows 75, 78. For this purpose, the leading edge, and wipers 15, 39, in general, can be oriented at angles 81, 84 from about ten degrees at about eighty degrees relative to the axis of rotation 48 or axial direction as shown. Alternatively, the angles 81, 84 may be on a scale of about thirty to forty-five degrees inclusive. The angles they can be internal or external to these scales insofar as they provide the function of displacing the formation of particles away from the seals 51, 54. As will be appreciated, if the cleaners are supported in the cutter housing 16 and the direction of rotation 66 of the cutting envelope 16 is the same, then the angle of the leading edges of the wipers 15, 39 do not require to be tilted in opposite manner to those shown in the sleeve 12 in Figure 2 to sweep the formation of particles out of the intermediate part between the cutting envelope 16 and the cutting sleeve 15. Referring again to Figure 1 B, the heights 87, 88 of the cleaners 15, 39 can be on a scale of about 0.794 centimeters to about 1.27 centimeters of a total size of the cutting head and other factors. The heights 87, 88 can be approximately 0.476 centimeters. These heights can be expressed as radial or diametric differences between the second portions 24, 25 and the first portions 21, 42 of the dynamic interface surfaces facing radially outwardly as shown and described in relation to Figure 1A. An alternative expression of the heights may be that the heights 87, 88 are from about one tenth to about five times a width 91 of the wipers 15, 39. Although the figures in the drawings are not necessarily to scale, it will be understood that the proportions Similar ones can be calculated by measurements and comparisons of the current drawing element in Figures 1A-4. For example, the width of the cleaners 15, 39 may be about one-tenth the diameter of the dynamic interface surfaces in which the wipers 15, 39 are supported. It will be understood that the proportion of the second portion of the dynamic surface relative to the first portion will generally be small, the proportion of the second and first portions may vary. For example, while only four equidistantly spaced apart relatively narrow cleaners 15, 39 are shown on a circumference of the dynamic surfaces at each end of the cutter sleeve 12, wider cleaners may be incorporated. For example, it is contemplated that the width 91 of a wiper 15, 39 can be at most about half the circumference of the dynamic surfaces on which the wiper 15, 39 is supported. It will be understood that wipers 15, 39 can, in most, if not all cases, have the heights 87, 88 of a smaller dimension than the normal separations between the dynamic interface surfaces that face radially between the sleeves of the cutter assembly and the cutting envelopes of the cutter assembly. Then, the custom design of the existing cutter assemblies may not be required in others than in the steps to provide the cleaners 15, 39 according to the present invention. For example, the first dynamic sleeve interface surface 18 shown in Figure 1 can be integral and form a part with the remainder of the cutter sleeve 12. Then, the interface surface of dynamic sleeve 18 can be machined together with the rest of the cutter sleeve 12 such as in a turning procedure to integrally form the dynamic sleeve interface surface 18 at the end of the larger diameter of the sleeve 12 together with the bearing surfaces 27, 30, and 33. The wipers 15 can be added to a custom machined sleeve or can be added to a standard cutter sleeve such as, for example, by welding and formed by a subsequent machining process. Similarly, the dynamic sleeve interface surface facing radially outwardly 36 may be formed at the end of the smaller diameter of the sleeve 12. Alternatively, interface surfaces may be formed on the surfaces facing radially inwardly of the sleeve. cutting envelope. However, it will be understood that in most cases in any given pair of dynamic interface surfaces facing each other, the cleaners may be on only one interface surface while the other surface remains smooth. Figures 3 and 4 show detailed views of alternative modalities of corresponding regions III and IV of the sectional view of Figure 1A. As can be appreciated, one or both of the dynamic interface surfaces can be added on the cutter sleeve 12 and / or the cutter shell 16. Figure 3 shows a sectional view of the region at the end of the larger diameter of the sleeve 12. Instead of the cleaner 5 being a piece with the sleeve 12, the cleaner is supported on a separable piece. While the detachable part can be any detachable part, Figure 3 shows the detachable part as a seal retainer 101 which is supported by the sleeve attachment structure 12. The attachment structure can include a notch 104 and slot 107 in the sleeve 12 and a retaining ring 110 received in the slot 107 and holding the retainer 101 in the groove 104. A further structure may include a channel in the retainer 101 and a tang in the sleeve 12 and for example, hooking the channel to inhibit the rotation of the retainer 101 relative to the sleeve 12. Alternatively or additionally, the joint structure can be provided as a threaded connection between the detachable part and the sleeve. In addition, alternatively or additionally, the joint structure can be provided by a combination of channel and bolt. As shown, the seal retainer 101 has a seal retainer structure which may include a generally catch-ring-washer and annulus capture cavity 113. Another washer cavity and annular seal is formed between the sleeve 12 and the cutting shell 16. Then, a seal 117 having two ring seals 120 and two washers 123 can form a dynamic seal between the cutter sleeve 12 and the cutting shell 16. Advantageously, the seal retainer can have the dual function of retaining the seal 117 and supporting the cleaner 15. As shown in Figure 4, the cleaner 39 can be similarly supported in a detachable part. While the separable piece can be any separable piece such as any segment of the sleeve or shell, Figure 4 shows the detachable part as a seal retainer 126 which is held by the sleeve attachment structure 12. The attachment structure may include a notch 129 and slot 132 in the sleeve 12 and a ring retainer 135 received in slot 132 and holding retainer 126 in notch 129. Alternatively or additionally, the attachment structure may be provided as a threaded connection between the detachable part and the sleeve. In addition, alternatively or additionally, the joint structure can be provided by a combination of channel and bolt. As shown and described with respect to Figure 3 above, the seal retainer 126 may have a seal retainer structure which may include a generally reentrant annular seal and washer capture cavity 138. Another washer cavity and annular seal can be formed between the sleeve 12 and the cutting shell 16. Then, a seal 141 having two ring seals 144 and two washers 147 can form a dynamic seal between the cutter sleeve 12 and the cutting shell 16 Advantageously, the seal retainer may have the dual function of retaining the seal 141 and supporting the cleaner 39. It is contemplated that the separable part may be provided as a pressure seal with the cleaners with or without the seal retainer structure. . This can be applied to either or both ends of the sleeve or the cutting shell as an annular segment. Alternatively or additionally, one or more separable pieces may have other configurations such as blocks that have cleaners or even how to clean junctures. The detachable part (s) may be attached to the cutting sleeves or shells by one or more sets of screws, bolts, welds, tongue structures and grooves that enable sliding, or threads in the same separable pieces. As described above, the wipers 15, 39 can be supported on any of the sleeves 12 or on the cutting wrapper 16 as indicated by the dashed lines in Figures 3 and 4. Additionally, the wipers 15, 39 can be supported on separable pieces that can be attached to the cutting envelope 16 in place of the cutter sleeve 12. Any combination of these teachings is within the spirit and scope of the present invention. A configuration described in Figure 1A can have a combination of a first seal that can be installed without a separable seal retainer at one end of the larger diameter of the sleeve 12 and a second seal that can be installed and held in place by a retainer separable seal as that shown and described in relation to Figure 4 at one end of smaller diameter of the sleeve 12. Then, the installation of seals and bearings can be facilitated. It will be understood that while the embodiments have been shown and described as having dynamic interface surfaces that generally define straight cylindrical surfaces that are parallel to the axis of rotation 45 for each of the sleeve and the housing, and for the cleaners 15, 39. It is say, the interface surfaces are shown as being of a generally constant radius along their extension in a direction of the axis of rotation 48, and the only differences in the radii are between the respective surfaces and between the surfaces and the wipers. , 39. However, the dynamic interface surfaces may be angled relative to the axis of rotation 48 on a scale of approximately forty-five degrees radially inward toward the axis 48 from the interior of the envelope 16 outward to approximately forty and five degrees radially outward from the inside of the enclosure 16 outwards. As shown in Figure 1 B, the angles may extend more typically radially inwardly toward the axle 48 only slightly from the inside outwards for the scales 150, 153 from about ten degrees radially inward from an interior to about thirty degrees radially. out from inside. The angles that correspond to the dynamic interface surfaces increase in radius in one direction from the inside to the outside have the advantage of displacing debris outward away from the seals 50 and about 54 in a path of least resistance because the volume The space between the sleeve and the envelope increases in an outward direction. Alternatively, incorporate an increased radius in directions away from the envelope and sleeve for the dynamic interface surfaces and further inhibit the packaging of debris in an area close to seals 51 and 54. This advantage can be seen more when considering that the The angles shown in two dimensions in Figure 1B actually correspond to the dynamic interface surfaces that are generally conically configured. The solid arrow 156 represents an enchantment direction for a dynamic interface surface of the sleeve 12 having a downward radius in an inward direction relative to the casing 16 and the sleeve 12. The solid arrow 159 represents an enchantment direction for a radially outer surface of the cleaner 39 on the dynamic interface surface with the facing direction 156. At an opposite end of the scale of angles shown for the dynamic interface surfaces in Figure 1B, the solid arrow 162 represents the facing direction of the dynamic interface surface of the sleeve 12 when the radius increases inwards. The solid arrow 165 represents the facing direction for the radially outer surface of the cleaner 39 on the dynamic interface surface with the facing direction 162. As stated above, the corresponding dynamic interface surface in the envelope generally coincides in shape and will be only slightly larger than the corresponding interface surface and wiper (s) of the sleeve for any angle within the scale. The broken arrow 168 represents a facing direction for a dynamic interface surface of the envelope 16 having a downward radius in an inward direction relative to the shell 16 and sleeve 12. The dashed arrow 171 represents a facing direction for a radially inner surface of the wiper 39 applied to the dynamic interface surface with the burial direction 168. At an opposite end of the scale of angles shown for the dynamic interface surfaces in Figure 1 B, the dashed arrow 174 represents the facing direction of the dynamic interface surface of the envelope 12 when the radius increases inwards. The dashed arrow 177 represents the facing direction for the radially outer surface of the wiper 39 applied to the dynamic interface surface with the facing direction 174. As stated above, the corresponding dynamic interface surface in the sleeve 12 generally coincides in shape and will be only slightly smaller than the corresponding interface surface and cleaners applied to the envelope 16 for any angle within the scale. It will be understood that the angle scales for the dynamic interface surfaces relative to the axis of rotation 48 described above can be applied to both ends of the sleeve assembly 12 and shell 16. Moreover, the angle scales can be applied to separable pieces that are coupled to one or both of the sleeve and shell according to the modalities shown in Figures 3 and 4. The embodiments and examples set forth herein were presented for a better explanation of the present invention and its practical application and thus enable to those with ordinary skill in the art to manufacture and use the invention. Do not However, those of ordinary skill in the art will recognize that the foregoing description and examples have been presented for the purposes of illustration and example only. The description as set forth is not intended to be exhaustive or to limit the invention to the precise form described. Many modifications and variations are possible in light of the above teachings without departing from the spirit and scope of the following claims. For example, while the cleaners have been shown and described as facing radially, it is contemplated that a similar advantage can be achieved with cleaners that face a different angle from the normal to a radial direction. Cleaners on dynamic interface surfaces that face between zero and ninety degrees relative to a radial direction are considered within the scope of the present invention. Dynamic interface surfaces and / or cleaners are considered to be radially facing when there is a radial component to the direction in which they are facing.

Claims (32)

NOVELTY OF THE INVENTION CLAIMS

1. - A replaceable cutter assembly comprising: a sleeve having at least one sleeve bearing surface, the sleeve having at least one dynamic sleeve interface surface facing radially outwardly; a cutting envelope rotatably supported on the sleeve, the cutting envelope has a cutting envelope bearing surface and the cutting envelope has at least one dynamic cutting envelope interface surface facing radially inward; and at least one cleaner in the at least one of the interface surfaces of one of the sleeve and the cutting shell; wherein the at least one cleaner is close to and faces at least one of the interface surfaces of the other of the sleeve and the cutting shell.

2. - The replaceable cutter assembly according to claim 1, further characterized in that the cleaner is a low profile ear formed integrally in one of the sleeve and the cutting shell.

3. - The replaceable cutter assembly according to claim 1, further characterized in that an axis of rotation of the cutting envelope in the sleeve defines an axial direction; and the cleaner it has an edge that extends generally diagonally in relation to the axial direction.

4. - The replaceable cutter assembly according to claim 1, further characterized in that an axis of rotation of the cutting envelope in the sleeve defines an axial direction; and the cleaner has an edge that extends generally helically relative to the axial direction.

5. - The replaceable cutter assembly according to claim 1, further characterized in that it additionally comprises a plurality of cleaners that can include the at least one cleaner, wherein the cleaners protrude radially from the at least one of the interface surfaces .

6. - The replaceable cutter assembly according to claim 5, further characterized in that an axis of rotation of the cutting envelope defines an axial direction, the plurality of cleaners comprises four permanent low profile lugs circumferentially spaced apart from each other in the at least one of the dynamic sleeve interface surfaces relative to the axis of rotation, wherein the permanent low profile lugs further comprise edges that extend generally diagonally relative to the axial direction.

7. - The replaceable cutter assembly according to claim 1, further characterized in that it additionally comprises at least one seal in sealing contact with the cutting envelope and the cutting sleeve between the dynamic interface surfaces of the cutting envelope and the cutting sleeve on one axial side and the rolling surfaces of the cutting envelope and the cutting sleeve on another axial side of the at least one seal.

8. The replaceable cutter assembly according to claim 1, further characterized in that it further comprises: a plurality of dynamic sleeve interface surfaces facing radially outwardly including the at least one dynamic sleeve interface surface facing radially outward; a plurality of dynamic cutting envelope interface surfaces facing radially inwardly including the at least one dynamic cutting envelope interface surface facing radially inward, the plurality of dynamic cutting envelope surfaces facing radially inward form respective pairs of interface surfaces with the plurality of dynamic sleeve interface surfaces facing radially outward; and at least one of the cleaners in at least one of the interface surfaces of each of the interface surface pairs; wherein each of the at least one of the cleaners is close to and faces the other interface surfaces of each of the pairs of interface surfaces.

9. A replaceable cutter sleeve comprising: a sleeve having at least one sleeve bearing surface and at least one dynamic sleeve interface surface facing radially outward; and at least one cleaner in the at least one interface surface.

10. The replaceable cutter sleeve according to claim 9, further characterized in that the dynamic sleeve interface surface facing radially outwardly comprises: at least a first portion having a first diameter; and at least one second raised portion having a second diameter greater than the first diameter; wherein the first and second portions extend along a common circumferential line.

11. The replaceable cutter sleeve according to claim 9, further characterized in that an axis of rotation of the sleeve defines an axial direction; and the dynamic sleeve interface surface facing radially outward extends circumferentially and is spaced proximally relative to the sleeve bearing surface in the axial direction.

12. The replaceable cutter sleeve according to claim 9, further characterized in that an axis of rotation of the sleeve defines an axial direction; and the cleaner has an edge that extends generally diagonally relative to the axial direction.

13. The replaceable cutter sleeve according to claim 9, further characterized in that it additionally comprises a plurality of cleaners that include the at least one cleaner, wherein: the cleaners form second portions of the interface surface of the cleaner. dynamic sleeve facing radially outward; and the cleaners protrude radially from the first portions of the at least one interface surface.

14. - The replaceable cutter sleeve according to claim 13, further characterized in that an axis of rotation of the cutting envelope defines an axial direction, the plurality of cleaners comprises four permanently low profile lugs spaced circumferentially from each other on the interface surface of dynamic sleeve relative to the axis of rotation, wherein the permanent low profile lugs further comprise edges extending generally diagonally relative to the axial direction.

15. - The replaceable cutter sleeve according to claim 9, further characterized in that at least a second portion of the dynamic sleeve interface surface facing radially outwardly comprises at least one cleaner formed integrally as a part with a first portion of the dynamic sleeve interface surface facing radially outwardly.

16. - The replaceable cutter sleeve according to claim 9, further characterized in that the dynamic sleeve interface surface is in a removable piece removably attached to the sleeve.

17. - The replaceable cutter sleeve according to claim 16, further characterized in that the detachable part comprises a seal retainer.

18. - The replaceable cutter sleeve according to claim 9, further characterized by additionally comprising a plurality of dynamic sleeve interface surfaces facing radially outwardly including the at least one dynamic sleeve interface surface facing radially outside.

19. - The replaceable cutter sleeve according to claim 18, further characterized in that each of the dynamic sleeve interface surfaces facing radially outward is on a removable piece removably attached to a remainder of the sleeve.

20. - A replaceable cutting envelope comprising: a cutting envelope having at least one cutting envelope bearing surface and at least one dynamic cutting envelope interface surface facing radially inward; and at least one cleaner in the at least one interface surface.

21. - The replaceable cutting envelope according to claim 20, further characterized in that the interface surface of dynamic cutting envelope facing radially inward comprises: at least a first portion having a first diameter; and at least a second raised portion having a second diameter smaller than the first diameter; wherein the first and second portions extend along a common circumferential line.

22. - The replaceable cutting envelope according to claim 20, further characterized in that an axis of rotation of the cutting envelope defines an axial direction; and the dynamic sleeve interface surface facing radially inward extends circumferentially and is spaced proximally relative to the rolling surface of the cutting envelope in the axial direction.

23. - The replaceable cutting envelope according to claim 20, further characterized in that an axis of rotation of the cutting envelope defines an axial direction; and the cleaner has an edge that extends generally diagonally relative to the axial direction.

24. - The replaceable cutting enclosure according to claim 20, further characterized in that it additionally comprises a plurality of cleaners that include the at least one cleaner, wherein: the letters form second portions of the dynamic cutting envelope interface surface that it faces radially inward; and the cleaners protrude radially from the first portions of the at least one interface surface.

25. The replaceable cutting envelope according to claim 24, further characterized in that an axis of rotation of the cutting envelope defines an axial direction, the plurality of cleaners comprises four separate permanent low profile lugs. circumferentially to each other on the dynamic cutting envelope interface surface relative to the axis of rotation, wherein the permanent low profile lugs further comprise edges extending generally diagonally relative to the axial direction.

26. The replaceable cutting envelope according to claim 20, further characterized in that the at least one second portion of the dynamic sleeve interface surface facing radially inward comprises the at least one cleaner formed integrally as a part. with a first portion of the dynamic sleeve interface surface facing radially inward.

27. A separate piece removably attached to at least one of a cutter assembly sleeve or cutter assembly cutter shell, the separate piece comprising: a radially facing dynamic interface surface having at least a first portion and a second portion, the first and second portions have first and second respective diameters different from each other, the first and second portions extend along a common circumferential line; and a joining structure on the separate piece for removably joining the piece to at least one of a cutter sleeve of the cutter assembly and a cutting envelope of the cutter assembly.

28. - The separate part according to claim 27, further characterized in that the separate part comprises a seal retainer having a seal retainer structure.

29. - The separate piece according to claim 27, further characterized in that the at least one of the first and second portions form low profile lugs with respect to the other of the first and second portions.

30. - A method for inhibiting the entry of debris into a raised drilling cutter assembly, the method comprising: sweeping a first dynamic interface surface that faces racially with at least one cleaner disposed on a second dynamic interface surface which faces radially in opposite manner; and displacing the debris axially away from at least one seal and at least one bearing of the cutter assembly; wherein the steps of sweeping and moving comprise automatic sweeping and displacement during normal rotation of a cutting envelope of the cutter assembly relative to a cutter sleeve of the cutter assembly.

31. - The method according to claim 30, further characterized in that the steps of sweeping and shifting comprise: presenting a leading edge of the at least one cleaner transverse to an axial direction defined by a shaft of rotation of the cutting envelope with relation to the cutter sleeve; and move the leading edge of the so minus one cleaner circumferentially along the second dynamic interface surface facing radially in opposite manner.

32. The method according to claim 30, further characterized by additionally comprising: sweeping a plurality of dynamic interface surfaces that face radially including the first dynamic interface surface facing radially with a plurality of cleaners including the at least one cleaner, the plurality of cleaners arranged in a plurality of dynamic interface surfaces facing each other in an opposite manner including the second dynamic interface surface facing radially in opposite manner; and moving the waste partially away from a plurality of seals including the at least one seal and displacing the waste axially away from a plurality of bearings including the at least one bearing of the cutter assembly; wherein the steps of sweeping and shifting comprise automatic sweeping and displacement during normal rotation of the cutting envelope of the cutter assembly relative to the cutter sleeve of the cutter assembly.