Patent Abstract:
A tool ( 10 ) for removing a cylinder bore liner (CL) from a cylinder bore of an engine. The tool is cam-actuated and allows for exchange of certain parts for use with different liner diameters.

Full Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to a tool that is used to remove a cylindrical object, such as a cylinder liner, from a hole, such as an engine cylinder bore. 
       BACKGROUND OF THE INVENTION 
       [0002]    A typical internal combustion engine comprises a cylinder block, typically cast metal, having cylinder bores. Cylindrical metal sleeves, commonly referred to as cylinder bore liners or just cylinder liners, are fit to the cylinder bores. For any of various reasons, it may become necessary to remove one or more cylinder liners from their bores. 
         [0003]    When cylinder liners must be removed from an engine that is installed in a motor vehicle, it is often preferable to allow the engine to remain in the vehicle and simply disassemble parts that provide access for removing the cylinders liners instead of removing the entire engine. 
         [0004]    If it is necessary for a mechanic to work underneath an engine in order to remove a cylinder liner, he or she is potentially exposed to falling debris from the engine and adjacent components and to coolant or oil spills. That is obviously an undesirable working environment. 
         [0005]    Ease of removal of a cylinder liner is of course desirable. Having to hammer a cylinder liner out of a bore using a hard synthetic part like a nylon rod or tube imposes impacts and stresses on parts of the human body and requires significant strength. Such impacts and stresses are undesirable as well. The task of removing cylinder liners is aggravated when a mechanic must be underneath an engine and hammer in a direction opposite the force of gravity. 
         [0006]    Recognizing undesirable factors such as those just mentioned, the applicant has invented a tool that facilitates removal of cylinder liners from cylinder bores. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention relates to a new and improved tool, sometimes referred to as a sleeve puller, for extracting a cylinder liner from a cylinder bore by exerting a pulling force on the liner. 
         [0008]    The tool can be used to remove a liner from a cylinder bore via the top of an engine, thereby avoiding the need for a mechanic to perform the operation from underneath the engine where he or she might be exposed to falling matter or spilling fluids, as pointed out above. 
         [0009]    The tool also inherently provides a mechanical advantage to the person using it thereby imposing lower stresses on the body and requiring less strength. 
         [0010]    The tool also features a construction that allows it to be used for extracting different diameter sleeves. End pieces, or feet, are pivotally and exchangeably mounted at opposite ends of a bar. By providing sets of feet of different lengths, a particular set of feet can be mounted on the bar to provide a proper diameter for extracting a particular diameter cylinder liner. 
         [0011]    One general aspect of the present invention relates to a tool for use in extracting a cylindrical sleeve from a bore in a body. 
         [0012]    The tool comprises a sleeve engagement part that has ends for radially overlapping a far end edge of a sleeve in a bore on opposite semi-circumferences of the sleeve and a center from which a rod extends perpendicularly. A reaction part is disposed perpendicular to the rod and has ends for radially overlapping a margin surface of the body surrounding the bore on opposite semi-circumferences of the margin surface. The reaction part also has a central clearance hole through which the rod passes. 
         [0013]    A screw thread threads the rod to a through-hole in a shaft that is perpendicular to the rod. An actuator part that can turn on the shaft about an axis of the shaft comprises a bearing surface that extends along a cam profile relative to the axis of the shaft. When the bearing surface is placed to bear against a surface of the reaction part with the reaction part itself bearing against the margin surface of the body, and with the ends of the sleeve engagement part engaging the far end edge of the sleeve, turning of the actuator part in one sense about the axis of the shaft applies force to the rod. That force is coupled to the sleeve engagement part and causes the sleeve engagement part to pull the sleeve toward the reaction part as the cam profile moves along the reaction part with turning of the actuator part. 
         [0014]    According to another general aspect of the invention, the sleeve engagement part has ends for radially overlapping a far end edge of the sleeve on opposite semi-circumferences of the sleeve. A rod extends perpendicularly from a center of the sleeve engagement part to a mechanism for transmitting a force through the rod to the sleeve engagement part to cause the sleeve engagement part to pull the sleeve toward the mechanism when the mechanism is actuated to extract the sleeve from the bore 
         [0015]    The sleeve engagement part comprises a central bar. Clevis joints pivotally mount end pieces containing the ends of the sleeve engagement part on ends of the bar for swinging motion about respective axes that lie on respective chords of the bore and that are constrained to swing within a range extending from a position of radial alignment with the bar toward a segment of the length of the rod that is between the bar and the mechanism. 
         [0016]    The clevis joints allow the end pieces to be disassembled from the bar and replaced by different end pieces. 
         [0017]    Another general aspect of the invention relates to a method of extracting a cylindrical sleeve from a bore in a body. 
         [0018]    The method comprises passing a sleeve engagement part of a tool through a sleeve with end pieces of the sleeve engagement part that are mounted on ends of a central bar for swinging about respective axes swung to clear the sleeve. 
         [0019]    When the sleeve engagement part has passed far enough the sleeve for the end pieces to clear a far end edge of the sleeve, the force of gravity is allowed to swing the end pieces against respective stops to respective positions that radially overlap the far end edge of the sleeve. A mechanism that is coupled to the sleeve engagement part is actuated to pull the sleeve engagement part to a position that places the end pieces against the far end edge of the sleeve. Continuing actuation of the mechanism pulls the sleeve engagement part and begins extracting the sleeve. 
         [0020]    The foregoing, along with further features and advantages of the invention, will be seen in the following disclosure of a presently preferred embodiment of the invention depicting the best mode contemplated at this time for carrying out the invention. This specification includes drawings, now briefly described as follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is a side elevation view of a tool embodying principles of the present invention. 
           [0022]      FIG. 2  is a partial view of the tool on a larger scale with parts of the tool in different positions from those in  FIG. 1 . 
           [0023]      FIG. 3  is a partial view of a portion of the tool on a larger scale. 
           [0024]      FIG. 4  is a view useful in understanding how the tool is used. 
           [0025]      FIG. 5  is a diagram illustrating further use. 
           [0026]      FIG. 6  is a view in the direction of arrows  6 - 6  in  FIG. 5 . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0027]      FIG. 1  shows the overall arrangement of a tool  10  that comprises a sleeve engagement part  12 , a reaction part  14 , and an actuator part  16 , each of which is associated in a particular way with a rod  18 . 
         [0028]    Sleeve engagement part  12  is an assembly that comprises a bar  20  that is rigidly attached at its center to an end of rod  18 , with the bar being perpendicular to the rod. Part  12  also comprises end pieces  22  at opposite ends of bar  20 . Each end piece  22  is pivotally mounted on bar  20  by a respective clevis joint  24 . Each clevis joint  24  comprises a pair of spaced apart ears  26  on piece  22  that straddle a single ear  28  on bar  20 . Each clevis joint is completed by a fastener  30  that passes through aligned holes in the three ears. 
         [0029]    Bar  20  has flat end surfaces  32  that are parallel with rod  18 . End pieces  22  have inner end surfaces  34  that are also flat. When tool  10  is in a vertically upright position, as in  FIG. 1 , the force of gravity acts on end pieces  22  in a manner that causes them to assume the position shown in  FIG. 2 , although  FIG. 1  shows them swung upwardly and inwardly about the pivot axis of the respective clevis joint toward a segment of the length of rod  18  that is between sleeve engagement part  12  and reaction part  14 . In the position of  FIG. 2 , each inner end surface  34  of end pieces  22  is abutting a respective end surface  32  of bar  20 . 
         [0030]    The outer ends of pieces  22  are contoured and have contoured undercuts  36  that associate with a cylinder liner (reference CL in  FIG. 4 ) when tool  10  is used as will be eventually explained at greater length. Each undercut  36  has a flat surface  38  that faces upward in  FIG. 2  and an adjoining surface  40  that is flat, but curved, and lies perpendicular to surface  38 . An end surface  42  below surface  38  is also flat, but curved. 
         [0031]    Reaction part  14  is an assembly that comprises a bar  46  at the center of which is a clearance hole  48  through which rod  18  passes. Near its ends bar  46  has through-slots  50  whose lengths parallel that of the bar. Cylindrical posts  52  are fastened to the underside of bar  46  by screws  54  that pass from the top side of the bar through through-slots  50  and are threaded into the posts. At their far ends, the posts have dowels  56 . 
         [0032]    Actuator part  16  is an assembly that comprises two circular parts  60 ,  62  of equal diameter disposed mutually parallel on opposite diametrical sides of rod  18  with their centers lying on a common axis. Parts  60 ,  62  are pivotally mounted on a stub shaft  64  such that the axis of the stub shaft is eccentrically parallel with the common axis of the two parts  60 ,  62 . Actuator part  16  further comprises a spacer  66  that is disposed between the two parts  60 ,  62  at a location spaced circumferentially from stub shaft  64 . Spacer  66  has a series of holes  68  in its side as shown in  FIG. 6 . 
         [0033]    Stub shaft  64  has a threaded hole  70  into which rod  18  is threaded. The axis of hole  70  lies on a diameter of the larger central portion of the stub shaft that is between the smaller diameter ends  72  that are received in holes in parts  60 ,  62 . Spacer  66  also has a through-hole that aligns with through-holes in parts  60 ,  62 . The shank of a headed bolt  74  passes through the three aligned though-holes, and a nut  76  that is tightened onto the bolt shank forces parts  60 ,  62  against ends of spacer  66  thereby holding parts  60 ,  62 ,  64 , and  66  in assembled relationship. 
         [0034]    Because of the eccentricity of the stub shaft axis to the common diameter of the two circular parts  60 ,  62 , the circular perimeters  78  of parts  60 ,  62  form a cam surface with respect to the stub shaft axis. 
         [0035]      FIG. 4  suggests how tool  10  is used. Sleeve engagement part  12  is inserted into the open upper end of an engine cylinder whose liner CL is to be removed. As end pieces  22  abut the top edge of liner CL, they swing to a position such as in  FIG. 1  to clear the liner. When the tool has been inserted far enough for end pieces  22  to clear a bottom end edge of the liner, the force of gravity causes them to swing to the position shown in  FIG. 4  where surfaces  34  abut surfaces  32 , and surfaces  38  radially overlap the bottom end edge of the liner. 
         [0036]    Reaction part  14  slides down on rod  18  to a position where dowels  56  fit into bolt holes in a surface of the cylinder block surrounding the cylinder bore. Actuator part  16  is then used to begin extracting liner CL from the bore. 
         [0037]    The end of a handle  80  shown in  FIG. 6  is inserted one of the holes  68  and used as a lever to begin turning parts  60 ,  62  clockwise about the axis of stub shaft  64 . The perimeters  78  of parts  60 ,  62  are forced against the top surface of bar  46  forcing reaction part  14  downwardly against the cylinder block. Because the reaction part cannot move downward, the movement of perimeters  78  across the top surface of bar  46  acts to cam stub shaft  64  upward. That motion is transmitted by rod  18  to sleeve engagement part  12 , causing end pieces to force liner CL upward toward reaction part  14  thereby freeing the liner and leading to its extraction from the bore. 
         [0038]    While a presently preferred embodiment of the invention has been illustrated and described, it should be appreciated that principles of the invention apply to all embodiments falling within the scope of the following claims.

Technology Classification (CPC): 1