Abstract:
A novel apparatus and method to engage a liner in an cylinder of an engine is provided. A wedge and rod are utilized as part of a liner remover assembly to move at least one collet axially to engage the liner. In a preferred embodiment, a novel eyehook is provided at an end of the rod to assist in the pulling of the liner from the cylinder.

Description:
This application is a divisional application of U.S. patent application entitled, “CYLINDER LINER REMOVAL,” filed Apr. 12, 2002, having a Ser. No. 10/120,383, the disclosure of which is hereby incorporated by reference in its entirety. 

   FIELD OF THE INVENTION 
   The present invention relates generally to an apparatus and a method to remove a liner. More particularly, the present invention relates to an apparatus and method to remove the liner from a cylinder of an engine. 
   BACKGROUND OF THE INVENTION 
   Conventional combustion, reciprocating engines are widely used as automotive engines. A conventional engine (single-cycle, two-cycle and others) is typically composed of an engine or cylinder assembly having one or more cylinders therein. A piston is slidably disposed in the cylinder and moves reciprocally within the cylinder. A cylinder head at one end of the cylinder closes the cylinder assembly. The cylinder head typically contains the valves (intake and exhaust) and the spark plug. A combustion chamber is defined by an inner wall of the cylinder, a top surface of the piston, along with the cylinder head. 
   During combustion, the piston moves reciprocally within the cylinder and eventually can wear down the inner walls of the cylinder. Cylindrical shaped liners have been developed to line the walls of the cylinder to increase the life of the cylinder. The liner may have coolant rings on its outer surface to form an annulus between the outer walls of the liner and the inner walls of the cylinder to provide a flow path for cooling liquid or air during combustion. When the liner is worn below a predetermined thickness, it can be replaced with another liner. However, over the course of the liner&#39;s life, the coolant rings may melt or other contaminants may harden and make it difficult to remove the liner by hand. 
   In order to remove a conventional liner, the cylinder head is removed from the cylinder assembly. A conventional liner remover is comprised of a cylindrically shaped rubber component that can be inserted into the liner and then compressed to expand and frictionally engage the liner to remove it from the cylinder. Because the components are rubber, the rubber tends to disintegrate over time or melts if the liner is still hot from a combustion event. Further, the rubber component can only be compressed to a certain point, thus it is limited to a certain diameter of liner and requires many liner removers to be on hand due to different sizes of liners in different engines. The liner can also become greasy due to contact with the fuel mixture or oil in the cylinder or the cooling rings around the liner can melt, thus making it difficult to remove the liner with the rubber components. 
   Therefore, there is a need for an apparatus and method to remove the liner that will not disintegrate over time, that can be adapted to any size liner, and can be expanded to better grip the liner. 
   SUMMARY OF THE INVENTION 
   Embodiments of the present invention generally provide for an improved method and liner removing assembly that can positively engage the liner and remove the liner from a cylinder of an engine. 
   In one embodiment, the liner removing apparatus can include a wedge coupled to a first end of a rod. At least one collet is provided and is capable of receiving at least a portion of the wedge and the rod. A plate can be coupled to the at least one collet and at least one nut. The at least one nut may be threadedly attached to the rod, which may have a lifting member mountable to a second end. Additionally, the apparatus can further include a first thrust bearing assembly that is at least partially enclosed by the plate and a retaining ring. A bridge that can support a second thrust bearing assembly is also provided, along with a second nut coupled to the second thrust bearing assembly. The apparatus can be made from a non-resilient material such as an alloy and can be selected from a group consisting of titanium, chromium, manganese, iron, nickel, copper, zinc, silver, tin, tungsten, platinum, gold, lead, steel, and a combination thereof. Additionally, the apparatus can be made from a polymer. Further, the at least one collet can have at least one flange at an end and can have at least one annular groove having at least one ring on its annular surface. The rod may be at least partially threaded along its outer surface. The lifting member can include an eyehook having at least one guiding member to guide a hook to a central portion and can be mounted by a pin received in the second end of the rod. 
   In a second embodiment, a liner remover assembly can include a wedge fastened to a first end of a rod, at least two or more collets forming a cavity capable of receiving at least partially the wedge and the rod, a plate coupled to the at least two or more collets and the rod, the plate at least partially enclosing a first thrust bearing assembly and a retainer ring, a first nut threaded to the rod, a bridge coupled to the rod, a second nut threaded to the rod, and a second thrust bearing assembly disposed between the second nut and the bridge. Additionally, the assembly can include a lifting member coupled to a second end of the rod. The at least two or more collets may have on its outer surface at least one annular groove to receive at least one ring and having at least one flange at an end. The assembly can be made from a non-resilient material such as an alloy and the alloy can be selected from a group consisting of titanium, chromium, manganese, iron, nickel, copper, zinc, silver, tin, tungsten, platinum, gold, lead, steel, and a combination thereof. The assembly can also be made from a polymer or a combination of alloy and polymer. Further, the lifting member may include an eyehook having at least one guiding member to guide a hook to a central portion of the eyehook. 
   A method of removing a liner from a cylinder in a combustible engine is also provided and can include inserting a liner removing assembly into the cylinder, the assembly comprising a wedge coupled to a first end of a rod and at least one collet to engage the liner, rotating a first nut to move the rod and the wedge in a first direction, engaging the liner by moving the at least one collet axially with the wedge, and rotating a second nut to move the liner from the cylinder. The method can also include lifting the liner removing assembly from the cylinder and removing the liner from the cylinder. The liner removing assembly preferably includes a plate at least partially enclosing a first thrust bearing assembly, a second thrust bearing assembly disposed between a bridge and the second nut, and a lifting member fastened to a second end of the rod. 
   A liner removing apparatus may include a means for supporting the liner removing apparatus, a means for gripping the liner in a cylinder, and a means for lifting the liner. Additionally, the means for supporting the liner removing apparatus can include a bridge. The means for gripping the liner may include a rod having a wedge at a first end, at least one collet capable of receiving at least partially the rod and the wedge, a first nut threaded to the rod and coupled to a plate, and a first thrust bearing assembly disposed at least partially in the plate. The means for lifting can preferably includes a second thrust bearing assembly disposed between a second nut and the bridge, the second nut threaded to the rod, and a lifting member coupled at a second end of the rod. 
   There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described below and which will form the subject matter of the claims appended hereto. 
   In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting. 
   As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a cross-sectional view of one embodiment of a liner remover assembly. 
       FIG. 2  is a cross-sectional view of the liner remover assembly engaging a liner from the cylinder. 
       FIG. 3  illustrates the removal of the liner. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  is a cross-sectional view of one embodiment of a liner remover assembly  10 . The assembly  10  is shown having three major portions. The first portion or gripping portion  11  is designed to engage the liner  70  in a cylinder assembly  75  (partially shown). The second portion or the securing portion  12  helps place the assembly  10  over the cylinder assembly  75  and provides support during removal of the liner  70 . The third portion or the removal portion  14  assists in the removal of the liner  70  from the cylinder assembly  75 . 
   The gripping portion  11  can preferably include a conical shaped wedge  15 , a rod  60 , at least one collet  20 , a plate  35 , a first thrust bearing assembly  42 , and a first nut  50 . The wedge  15  can be any shape so long as it able to engage the liner  70  as required. The wedge  15  can preferably be made from a metal, an alloy such as titanium, chromium, manganese, iron, nickel, copper, zinc, silver, tin, tungsten, platinum, gold, lead, steel or similar materials. However, the wedge  15  may also be made from a polymer or a combination of polymers. The wedge  15  can be solid or at least partially hollowed (as shown) so long as it is strong enough to cause the collet  20  to engage the liner  70  as required. The wedge  15  can be threaded and/or welded at a first end  17  of the rod  60 . The rod  60  has one or more threads on its outer surface. The collet  20  as used herein may be anything that has one surface that can mate with the liner  70  and another surface that can mate with the wedge  15 . The collet  20  can be solid or at least partially hollowed so long as it is strong enough to engage the liner  70  as required. One or more collets  20  may be provided and can form a cavity  23  to receive the wedge  15  and the rod  60 , however, preferably there are two collets  20 , and more preferably there are four collets  20 . The inner surface of the collet  20  and the outer surface of the wedge  15  are complementary to each other to provide maximum contact with each other. The collet  20  can preferably be made from a metal, an alloy such as titanium, chromium, manganese, iron, nickel, copper, zinc, silver, tin, tungsten, platinum, gold, lead, steel or similar materials. However, the collet  20  can also be made from a polymer or a combination of polymers that can engage and grip the liner  70 . The collet  20  may have on the outer surface at least one or more annular grooves  32  to receive one or more rings  30 . Rings  30  bind the collets  20  together until they are expanded radially by the wedge  15 . A flange  25  is provided at one end of the collet  20  to mate with an upper surface of the cylinder assembly  75  and preferably allows the collet, the wedge  15  and a portion of the rod  60  to enter the liner  70 . 
   The gripping portion  11  also includes the plate  35  that may be annularly shaped and can encapsulate the first nut  50  and the first thrust bearing assembly  42 . The first thrust bearing assembly  42  can further include a retaining ring  40 , and a first thrust bearing  41  that can be disposed between a first set of washers  37 . The first thrust bearing assembly  42  may serve to decrease the friction between the plate  35  and the first nut  50 , thereby making it easier to turn or torque the first nut  50 . The plate  35  may be coupled to the collets  20  to prevent the collets from travelling in an axial direction when the first nut  50  is rotated in a first direction, thereby moving the wedge  15  and rod  60  in an axial direction. The plate  35  may be solid or may have apertures or slots therein for viewing into the cylinder  75 . Additionally, the plate  35  may be any shape so long as it prevents the movement of the collets  20  axially when required. The first nut  50 , the annular plate  35 , and the first thrust bearing assembly  42  are threaded or coupled to the rod  60 . 
   In the gripping operation, a torquing apparatus such as a wrench, pliers or similar apparatus (not shown) torques (or turns) the first nut  50  in the first direction causing the first end  17  of rod  60  and the wedge  15  to move towards the first nut. This movement causes the wedge  15  to move further into the cavity  23  and forces the collets  20  radially outward to engage the liner  70  as shown in  FIG. 2 . The first nut  50  can be torqued in the first direction, as required, to force the collets  20  to expand radially and grip the liner  70 . Additionally, the collets  20  can be expanded radially to fit various sizes of liners  70 , thereby decreasing the number of liner remover assemblies  10  required to be available at the shop. 
   The securing portion  12  can include a bridge  45  that can be constructed and arranged to mate with an upper surface of the cylinder assembly  75 . The bridge  45  may include a platform  47  and at least one supporting member  49 , but preferably has two or more supporting members. The bridge  45  can provide the initial support for the assembly  10  when it is placed on the cylinder assembly  75 . Additionally, the bridge  45  can assist in the removal of the liner  70  from the cylinder assembly  75  by providing support for a second nut  55  to rotate the rod  60  which lifts the gripping portion  11  and the liner  70 . The bridge  45  can preferably be from a metal or an alloy such as titanium, chromium, manganese, iron, nickel, copper, zinc, silver, tin, tungsten, platinum, gold, lead, steel or similar materials. However, the bridge  45  can also be made from a polymer or a combination of polymers that are capable of withstanding the force required to lift the liner  70  from the cylinder assembly  75 . Additionally, the bridge  45  and the support members  49  may be annular in shape or any other shape so long as it provides support as described above. 
   The removal portion  14  can include a second thrust bearing assembly  51 , a second nut  55  and a second end  80  of the rod  60 . The second thrust bearing assembly  51  may be positioned between the second nut  55  and the bridge  45 , and can include a second set of washers  39  having a second thrust bearing  48  disposed between the washers. The second end  80  of rod  60  can be adapted to receive a lifting member such as an eyehook  90  ( FIG. 2 ), which can be attached to a conventional hook and chain. The second end  80  can further include an aperture to receive a pin  65  therein. The pin  65  can secure the eye hook  90  to the rod  60 . The eye hook  90  can be attached at all times or attached when it is needed such as to lift a heavy liner  70  or stuck liner that requires additional force. The second nut  55  and the second thrust bearing assembly  51  can be threaded or coupled to rod  60 . 
   In the removal operation ( FIG. 3 ), the torquing apparatus can be applied to the second nut  55  in the first direction, which rotates the rod  60 , causing the gripping portion  11 , and liner  70 , to move axially towards the second nut. The torquing can continue until the liner  70  is removed at least partially from the cylinder assembly  75  or at a point where the liner can be removed by hand or other means. 
     FIG. 2  is a cross-section view of the liner remover assembly  10  engaging a liner  70  from the cylinder assembly  75 . The liner remover assembly  10  is placed on an upper surface of the cylinder assembly  75  and the collets  20 , wedge  15  and a portion of the rod  60  is inserted into the cylinder to engage the liner  70 . The first nut  50  is torqued, thereby causing the rod  60  and the wedge  15  to move axially and forcing the collets  20  to move radially outward and engage the liner  70 . 
     FIG. 2  also illustrates an alternative embodiment of the liner remover assembly  10  wherein a lifting member such as a handle or an eyehook  90  is attached to the second end  80  of the rod  60 . The eye hook  90  is constructed and arranged for use with a hand or other devices such as a hook and chain. The eyehook  90  can include a central region  95  capable of receiving a hook (not shown) or similar devices. The central region  95  can be partially defined by a first guiding member  100  and a second guiding member  102  that converge at point  105 . The guiding members  100 ,  102  can guide a hook to point  105  if the hook is initially placed on either guiding member  100 ,  102 . By having the hook at point  105 , the liner remover assembly  10  can be balanced and the liner  70  can be lifted with minimal swaying. 
     FIG. 3  illustrates the removal of the liner  70 . The second nut  55  has been torqued by the torquing apparatus (not shown) causing the rod  60  to travel in the direction indicated by the arrow. Once the liner  70  is moved passed a certain point in the cylinder assembly  75 , it can be easily removed. The collets  20  can be disengaged from the liner  70  by rotating the first nut  50  in a second direction, thereby allowing the liner to be removed by hand, pliers or similar devices. Alternatively, a hand (human) or hook can be used to grab the eyehook  90  and lift the entire liner remover assembly  10  along with the engaged liner  70  from the cylinder assembly  75 . Additionally, all the components described above and herein can be made from a polymer, a metal or an alloy such as titanium, chromium, manganese, iron, nickel, copper, zinc, silver, tin, tungsten, platinum, gold, lead, steel or any combination thereof. 
   The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirits and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.