LOW-FRICTION, ABRASION RESISTANT REPLACEABLE BEARING SURFACE

Abstract

Low-friction, abrasion resistant systems of replaceable bearing surfaces and methods of using the system are disclosed. The system comprises a device having at least one recess, each recess having a groove in an inner wall of the recess; a plurality of replaceable bearing surfaces adapted to be inserted into and removed from the at least one recess without damaging the device; and at least one snap ring adapted to engage the groove in each recess and secure a replaceable bearing surface within the recess.

Claims

1. A low-friction, abrasion resistant system of replaceable bearing surfaces, comprising: a device having at least one cylindrical recess with a wall, the at least one recess having a hole in the wall and a cavity in the wall diametrically opposed to the hole; a plurality of replaceable bearing surfaces adapted to be inserted into and removed from the at least one recess without damaging the device, each replicable bearing surface having a hole; and at least one cross-pin adapted to be threaded through the hole in the wall of the recess, through the hole in a replaceable bearing surface, and into the cavity in the wall of the recess.

2. The system of claim 1, wherein each replaceable bearing surface is comprised of one of steel or Polycrystalline Diamond Compact (PDC).

3. The system of claim 1, further comprising at least one conical spring adapted to be placed between the bottom of the recess and a replaceable bearing surface.

4. The system of claim 1, further comprising at least one guard adapted to be positioned between the recess and a replaceable bearing surface.

5. The system of claim 1, wherein each replaceable bearing surface has a domed outer surface.

6. The system of claim 5, wherein the outer surface of each replaceable bearing surface extends beyond an external surface of the device when placed within a recess.

7. The system of claim 1, wherein the device is one of a drill bit, a reamer, a cam shaft, a bearing, or an axle.

8. The system of claim 1, wherein the cross-pin is radially sprung to maintain a friction fit when positioned within the device and a replaceable bearing surface.

9. A method of installing and replacing bearing surfaces in a device, comprising: providing a device having at least one cylindrical recess with a wall, the at least one recess having a hole in the wall and a cavity in the wall diametrically opposed to the hole; removing any damaged or used replaceable bearing surfaces from each recess without damaging the device; providing a plurality of replaceable bearing surfaces, each replicable bearing surface having a hole; inserting one replaceable bearing surface into the at least one recess without damaging the device; providing at least one cross-pin; inserting a cross-pin through the hole in the wall of the recess, through the hole in a replaceable bearing surface, and into the cavity in the wall of the recess.

10. The method of claim 9, further comprising adapting the replaceable bearing surface to be comprised of one of steel or Polycrystalline Diamond Compact (PDC).

11. The method of claim 9, further comprising inserting at least one conical spring between the bottom of the recess and the replaceable bearing surface.

12. The method of claim 9, further comprising inserting at least one guard between the recess and the replaceable bearing surface.

13. The method of claim 9, further comprising adapting each replaceable bearing surface to have a domed outer surface.

14. The method of claim 13, further comprising adapting the outer surface of each replaceable bearing surface to extend beyond an external surface of the device when placed within a recess.

15. The method of claim 9, wherein the device is one of a drill bit, a reamer, a cam shaft, a bearing, or an axle.

16. The method of claim 9, wherein the cross-pin is radially sprung to maintain a friction fit when positioned within the device and a replaceable bearing surface.

Description

DESCRIPTION OF THE DRAWING

[0017] The invention is described in greater detail by way of example only and with reference to the attached drawing, in which:

[0018] FIG. 1 is an isometric view of an embodiment of the bearing surface of the invention.

[0019] FIG. 2 is a top view of an embodiment of the bearing surface of the invention.

[0020] FIG. 3 is a cut-away view of an embodiment of the bearing surface of the invention.

[0021] FIG. 4 is a side view of an embodiment of the bearing surface installed in a device.

[0022] FIGS. 5A-B depict a top and cutaway side view of an embodiment of recess in a device adapted to receive bearing surfaces.

[0023] FIGS. 6A-B depict a top and cutaway side view of an embodiment of a bearing surface placed within the recess depicted in FIGS. 5A-B. FIGS. 7A-B depict a top and cutaway side view of another embodiment of a bearing surface placed within the recess depicted in FIGS. 5A-B.

[0024] FIGS. 8A-B depict a top and side view of the embodiment of the bearing surface depicted in FIGS. 7A-B.

[0025] FIG. 9 depicts a cutaway side view of another embodiment of a bearing surface of the invention.

DESCRIPTION OF THE INVENTION

[0026] As embodied and broadly described herein, the disclosures herein provide detailed embodiments of the invention. However, the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. Therefore, there is no intent that specific structural and functional details should be limiting, but rather the intention is that they provide a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention.

[0027] A problem in the art capable of being solved by the embodiments of the present invention is replacing worn out bearing surfaces quickly and on-site. It has been surprisingly discovered that providing a replaceable low-friction, abrasion and impact resistant bearing surface allows technicians to replace worn out bearing surfaces themselves without transporting the device to a specialty facility.

[0028] FIG. 1 depicts an isometric view of a preferred embodiment of the replaceable bearing surface 100. Bearing surface 100 is comprised of an outer housing 105 and a slider button 110. While one slider button 110 is shown, another number of slider buttons can be used, for example, two or four slider buttons can be used. Preferably, the slider button 110 is a PDC, which has a lower coefficient of friction that carbide or hardened steels. The low coefficient of friction reduces drag during use of the device and thus reduces torque, for example, during drilling of lateral well bores. However, other materials, such as aluminum oxide, silicon carbide, or cubic boron nitride can be used. In the preferred embodiment, slider button 110 is semi-spherical, however other shapes (for example, rectangular, triangular, or semi-ovoidal) can be implemented. Additionally, slider button 110 can be a combination of shapes. Slider button 110 is preferably press fit into outer housing 105. However, slider button 110 can be coupled to outer housing 105, for example, with bolts, screws, adhesive, other fastening devices, or screwed into outer housing 105.

[0029] Preferably, outer housing 105 is comprised of 41/30 steel, however other steels or other materials can be used for outer housing 105. For example, nylon, other metals, plastics, carbon-fiber, or other naturally occurring or manmade materials. As can be seen in FIG. 2, outer housing 105 is preferably cylindrical, having an outer diameter of about one inch. However, outer housing 105 can have other dimensions depending on the device into which bearing surface 100 is installed. For example, outer housing 105 can have a diameter of an inch, 2 inches, or 3 inches. Outer housing 105 preferably has a notched portion 115 on the outer diameter, adjacent to slider button 110. Notched portion 115 is preferably adapted to be griped by a wrench, pliers, or a person's fingers. Notched portion 115 preferably aids in installing and uninstalling bearing surface 110 by providing a grippable surface. Outer housing 105 can additionally have other gripping surfaces or a smooth surface. For example, outer housing 105 can have raised knurling, a rubberized grip, or other high friction surfaces.

[0030] FIG. 3 depicts a cut-away side view of bearing surface 100. Outer housing 105 additionally preferably comprises a threaded portion 120. Threaded portion 120 preferably is able to mate with a threaded socket in the apparatus into which bearing surface 100 is to be installed. In other embodiments, instead of or in addition to treaded portion 120, outer housing 105 may have a spring biased cam, a friction increasing device, a pin, adhesive, or another fastening device to keep bearing surface 100 from unintentionally coming out of the apparatus. Preferably, the coupling device is capable of maintaining the outer housing 105 within the apparatus during use of the apparatus and under high stress and high heat conditions.

[0031] As shown in FIG. 4, bearing surface 100 is couplable with a device or apparatus. In the preferred embodiment the bearing surface 100 is counter sunk into the device so that only a portion of the bearing surface 100 extends beyond the exterior or the device. For example, only the slider button 110 may extend beyond the exterior of the device. The device can be a drill bit, a reamer, a cam shaft, a bearing, an axle, another machine part, or any other device requiring a low-friction surface. Preferably, the device has a recess with threaded sides that mates with threaded portion 120 of outer housing 105. In embodiments where outer housing 105 has another fixation device, the recess may have other mating devices. Preferably, the bearing surface 100 can be replaced at the location of use of the device with common tools (for example wrenches, pliers, or screw drivers). Preferably, the bearing surface 100 can be replaced without heating and/or cooling the device, thereby reducing the stress on the device caused during the refurbishment techniques used previously. Additionally, the precision tolerances of the devices can be maintained and repeated during replacement of the bearing surface 100. Since the bearing surface 100 can preferably be replaced on-site, a transportation cost savings is realized by reducing the number of trips to repair centers. Furthermore, redundant inventory can be reduced since the time previously necessary for shipping and repair is eliminated.

[0032] FIGS. 5A-B, 6A-B, 7A-B, and 8A-B depict embodiments of the bearing surface using a snap ring retention device. FIG. 5A is a top view of a recess 550 in a device 555 and FIG. 5B is the cutaway side view thereof. Device 555 can be drill bit, a reamer, a cam shaft, a bearing, an axle, another machine part, or any other device requiring a low-friction surface. Preferably, recess 550 has a cylindrical shape with a flared opening 560. However, recess 550 can have another shape. For example, recess 550 can be semispherical, pyramidal, cubical, or conical. Preferably, a portion of the inner surface of recess 550 is grooved 565. Preferably, groove 565 extends into the body of device 555. In a preferred embodiment, the flared opening 560 of recess 550 may extend further into the body of device 555 than the groove 565 extends. However, in other embodiments the flared opening 560 may be smaller or equal in size to groove 565. Preferably, groove 565 is positioned within the outer third of recess 565. However, groove 565 can have another positioning.

[0033] FIG. 6A is a top view of recess 550 with bearing surface 600 placed therein and FIG. 6B is a cutaway side view thereof. Bearing surface 600 may be a PDC, an impact resistant steel, or another material with a low coefficient of friction. Preferably, the coefficient of friction of bearing surface 600 is lower than the coefficient of friction of the material of device 555. Preferably bearing surface 600 is cylindrical in shape with a domed outer surface. However, bearing surface 600 can have another shape, for example spherical, semispherical, cubical, conical, or another shape. Furthermore, bearing surface may have a flat, chamfered, beveled, or other shaped outer surface. Preferably, bearing surface 600 is contained within a collar 670. Collar 670 can be of the same material as bearing surface 600, the same material as device 555, or of another material. Preferably, bearing surface 600 is press fit into collar 670. However, baring surface 600 and collar 670 can be coupled using a different method, for example, adhesive, welding, a threaded coupling, pins, screws, bolts, or another fastening device. Preferably, the outer diameter of collar 670 is slightly smaller than the inner diameter of recess 550 so that when collar 670 and bearing surface 600 are placed within recess 550 they do not move freely. Preferably, once placed within recess 550, bearing surface 600 extends beyond the outer surface of device 555. Preferably, collar 670 extends a portion of the way up bearing surface 650. Preferably, the height of collar 670 is equal to the height of groove 565 such that when collar 670 and bearing surface 600 are placed within recess 550 the upper surface of collar 670 is adjacent to groove 565.

[0034] A snap ring 675 is preferably inserted over collar 670 and into groove 565 to retain collar 670 and bearing surface 600 in recess 550. Snap ring (or retaining ring) 675 is preferably a removable device that can be squeezed into recess 550 and then extend into groove 565 such that a portion of snap ring 675 is within groove 565 and a portion of snap ring 675 extends over collar 670. In other embodiments, collar 670 can be held into recess 550 by a spring loaded cam, a pin, a screw, adhesive, a clevis, or another fastening device. Additionally recess 550 may have an opening 580 by which snap ring 675 can be squeezed for insertion and removal. In the preferred embodiment, to replace bearing surface 600, snap ring 675 is removed, the broken or used bearing surface 600 and collar 670 are then removed. A new bearing surface 600 and collar 670 are inserted into recess 550 and snap ring 675 (either the original or a replacement) is inserted into groove 565.

[0035] FIG. 7A is a top view of recess 550 with bearing surface 700 placed therein and FIG. 7B is a cutaway side view thereof. FIGS. 8A and 8B are top and side views of bearing surface 700. Bearing surface 700 may be a PDC, an impact resistant steel, or another material with a low coefficient of friction. Preferably, the coefficient of friction of bearing surface 700 is lower than the coefficient of friction of the material of device 555. Preferably, bearing surface 700 is a single unit that is cylindrical in shape with an upper portion 780 has a smaller radius than the lower portion 785. Preferably, the outer surface of upper portion 780 is domed. However, bearing surface 600 can have another shape, for example spherical, semispherical, cubical, conical, a combination thereof, or another shape. Furthermore, bearing surface may have a flat, chamfered, beveled, or other shaped outer surface. Preferably, there is a transition zone 790 between the upper portion 780 and the lower portion 785. Preferably, the outer diameter of lower portion 785 is slightly smaller than the inner diameter of recess 550 so that when bearing surface 700 is placed within recess 550 it does not move freely. Preferably, once placed within recess 550, bearing surface 700 extends beyond the outer surface of device 555. Preferably, the height of lower portion 785 is equal to the height of groove 565 such that when bearing surface 700 is placed within recess 550 the upper surface of lower portion 785 is adjacent to groove 565. In a preferred embodiment, upper portion 780 is milled from lower portion 785. However, upper portion 780 and lower portion 785 can be formed in different methods, for example, 3D printed, molded, etched, lathed, or a different technique.

[0036] A snap ring 775 is preferably inserted over lower portion 785 and into groove 565 to retain bearing surface 700 in recess 550. Snap ring (or retaining ring) 775 is preferably a removable device that can be squeezed into recess 550 and then extend into groove 565 such that a portion of snap ring 775 is within groove 565 and a portion of snap ring 775 extends over lower portion 785. In other embodiments, lower portion 785 can be held into recess 550 by a spring loaded cam, a pin, a screw, adhesive, a clevis, or another fastening device. Additionally, recess 550 may have an opening 580 by which snap ring 775 can be squeezed for insertion and removal. In the preferred embodiment, to replace bearing surface 700, snap ring 775 is removed, the broken or used bearing surface 700 is then removed. A new bearing surface 700 is inserted into recess 550 and snap ring 775 (either the original or a replacement) is inserted into groove 565.

[0037] FIG. 9 depicts another embodiment of a bearing surface 900 held into recess 950 in device 955 with a cross-pin 992. Device 955 can be drill bit, a reamer, a cam shaft, a bearing, an axle, another machine part, or any other device requiring a low-friction surface. Preferably, recess 950 has a cylindrical shape with a flared opening 960. However, recess 950 can have another shape. For example, recess 950 can be semispherical, pyramidal, cubical, or conical. In the preferred embodiment, after bearing surface 900 is placed within recess 950, cross-pin 992 is threaded through a hole 993 in the side of device 955 that is perpendicular to recess 950, through a corresponding hole 994 in bearing surface 900, and into a cavity 991 in the wall of recess 950. Preferably, cross-pin 992 slides in and out of holes 993 and 994 and is radially sprung so that cross-pin 992 maintains engagement to the holes with friction. Preferably, cross-pin 992 is removed in order to replace bearing surface 900. In other embodiments, cross-pin 992 may be kept in place with threading, adhesive, or another fixture.

[0038] Additionally, within recess 950 may be placed a Belleville (or conical spring) washer 995 to help absorb the impacts experienced by bearing surface 900. While a Belleville washer is shown, other impact absorbing devices may be used. For example, springs, fabrics, foams, or another deformable medium. Preferably washer 995 is placed within recess 950 prior to baring surface 900 being inserted. Additionally, guards 996 and 997 may be placed within recess 950 prior to insertion of bearing surface 900. Preferably guard 996 is position in the bottom of recess 950 and guard 997 is positioned around the interior surface of recess 950. Preferably, guards 996 and 997 protect device 955 from wear during use and replacement of bearing surface 900. Preferably guards 996 and 997 are metal, however they can be made of another material, such as fabric, plastic, or a combination thereof.

[0039] Other embodiments and uses of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. All references cited herein, including all publications, U.S. and foreign patents and patent applications, are specifically and entirely incorporated by reference. It is intended that the specification and examples be considered exemplary only with the true scope and spirit of the invention indicated by the following claims. Furthermore, the term comprising of includes the terms consisting of and consisting essentially of.