Patent Publication Number: US-11643308-B2

Title: Drive shaft removal tool

Description:
BACKGROUND OF THE INVENTION 
     1) Field of the Invention 
     The present invention relates to a tool for removing drive shafts such as a propeller shaft for an outboard engine, which is also occasionally referred to as a marine outdrive. While discussed in relation to the removal of a propeller shaft from a marine outdrive, the present invention and/or embodiments thereof, could be used to remove drive shafts from other types of engines too. Therefore, the terms “drive shaft” and “propeller shaft” may be used interchangeably as too may the terms “gear housing” “transmission housing” and/or “shaft housing.” 
     2) Description of Related Art 
     From time to time propeller shafts for a marine outdrive need to be removed for replacement, cleaning and/or maintenance purposes. Given that the marine outdrive is in contact with saltwater, a salt buildup develops at the seal and/or connection point where the propeller shaft is inserted into the shaft housing. The salt buildup acts as a binding agent making the removal of the propeller shaft very difficult. 
     Prior art tools typically use a manual pulling force to remove the propeller shaft. One such prior art device uses a slide hammer to create the pulling force, while other prior art devices use manual screw type jacks, which are attached to the propeller shaft by chains, wire, rope or the like. These prior art tools seldom provide a sufficient pulling force to break the bond between the propeller shaft and the shaft housing that is caused by the salt buildup. Therefore, these prior art devices often require the use of a hand held torch that is used to heat the shaft housing so as to cause expansion and, thus, breaking the bond caused by the salt buildup. 
     Use of such a torch or other heat source is not only dangerous to the user, it can damage the shaft housing. Repeated heating and cooling of the shaft housing is likely to weaken the housing over time. Moreover, it is often necessary to heat the shaft housing to a very high temperature to allow the metal to sufficiently expand and break the bond. Also, these prior art devices take an undesirable amount of time to remove the propeller shaft because they must first heat the shaft housing to a high temperature, which can take a long time when using a hand torch. 
     Accordingly, it is an object of the present invention to provide a device that can quickly and safely remove a drive shaft from the shaft housing. 
     It is another objective to provide a device that can remove a drive shaft from the shaft housing without requiring the user of the device to exert any pulling force personally. 
     It is another objective to provide a device that can remove a drive shaft from the shaft housing without requiring the use of a heat source. 
     It is another objective to provide a device that can be quickly mounted on and/or dismounted from the drive shaft to be removed. 
     SUMMARY OF THE INVENTION 
     The above objectives are accomplished according to the present invention by providing An apparatus for removing a shaft from a transmission comprising: a lower housing having a first end and a second end, wherein said lower housing includes an inner surface having an inner diameter and an outer surface having an outer diameter; an upper housing having a first end and a second end, wherein said second end of said upper housing is carried by said first end of said lower housing and said first end of said upper housing defines a jack opening; an inner guide conduit system carried by said inner surface of said lower housing, wherein said inner guide conduit system comprises: a central conduit and a support member having a first end that is carried by said central conduit and a second end that is carried by said inner surface of said lower housing; a jack support chamber that is adapted to house a hollow body jack and is defined by at least a portion said upper chamber, a portion of said lower chamber and a portion of said inner guide conduit system such that at least a portion of said upper chamber is adjacent the hollow body jack&#39;s upper surface, at least a portion of said lower chamber is adjacent to the hollow body jack&#39;s outer surface and at least a portion of said inner guide conduit is adjacent to the hollow body jack&#39;s lower surface; a viewing chamber that disposed below said jack support chamber and is defined by at least a portion of said lower housing and at least a portion of said inner guide conduit system, wherein at least a portion of said lower housing includes a viewing window to provide access to said viewing chamber; an extension rod that is adapted to be received by said jack opening in said upper housing and by said central conduit; a shaft coupler that is adapted to receive and secure a first end of said extension rod to a drive shaft; and, a shaft securing member that is adapted to receive and secure a second end of said extension rod to a piston of the hollow body jack. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The construction designed to carry out the invention will hereinafter be described, together with other features thereof. The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown and wherein: 
         FIG.  1    shows a front elevation view of an embodiment of the present invention. 
         FIG.  2    shows a rear elevation view of an embodiment of the present invention. 
         FIG.  3 A  shows a front elevation of the lower housing of an embodiment of the present invention. 
         FIG.  3 B  shows a top plan view of the lower housing of an embodiment of the present invention. 
         FIG.  3 C  shows a rear elevation view of the lower housing of an embodiment of the present invention. 
         FIG.  3 D  shows a right side elevation view of the lower housing of an embodiment of the present invention. 
         FIG.  4 A  shows a cross section view of the upper housing of an embodiment of the present invention. 
         FIG.  4 B  shows a rear elevation view of the upper housing of an embodiment of the present invention. 
         FIG.  4 C  shows a top plan view of the upper housing of an embodiment of the present invention. 
         FIG.  4 D  shows a top plan view of the upper housing cap of an embodiment of the present invention. 
         FIG.  4 E  shows a side elevation view of the upper housing cap of an embodiment of the present invention. 
         FIG.  5 A  shows an elevation view of a guide conduit of an embodiment of the present invention. 
         FIG.  5 B  shows a top plan of a support member of an embodiment of the present invention. 
         FIG.  5 C  shows a side elevation view of a support member of an embodiment of the present invention. 
         FIG.  6    shows a cross sectional view of an embodiment of the present invention. 
         FIG.  7 A  shows a top plan view of the base for an embodiment of the present invention. 
         FIG.  7 B  shows a side elevation view of a base for an embodiment of the present invention. 
         FIG.  8    shows a cross sectional view of an embodiment of the present invention. 
         FIG.  9    shows a cross sectional view of an embodiment of the present invention during use. 
     
    
    
     It will be understood by those skilled in the art that one or more aspects of this invention can meet certain objectives, while one or more other aspects can meet certain other objectives. Each objective may not apply equally, in all its respects, to every aspect of this invention. As such, the preceding objectives can be viewed in the alternative with respect to any one aspect of this invention. These and other objectives and features of the invention will become more fully apparent when the following detailed description is read in conjunction with the accompanying figures and examples. However, it is to be understood that both the foregoing summary of the invention and the following detailed description are of a preferred embodiment and not restrictive of the invention or other alternate embodiments of the invention. In particular, while the invention is described herein with reference to a number of specific embodiments, it will be appreciated that the description is illustrative of the invention and is not constructed as limiting of the invention. Various modifications and applications may occur to those who are skilled in the art, without departing from the spirit and the scope of the invention, as described by the appended claims. Likewise, other objectives, features, benefits and advantages of the present invention will be apparent from this summary and certain embodiments described below, and will be readily apparent to those skilled in the art. Such objectives, features, benefits and advantages will be apparent from the above in conjunction with the accompanying examples, data, figures and all reasonable inferences to be drawn therefrom, alone or with consideration of the references incorporated herein. 
     DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
     With reference to the drawings, the invention will now be described in more detail. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the presently disclosed subject matter belongs. Although any methods, devices, and materials similar or equivalent to those described herein can be used in the practice or testing of the presently disclosed subject matter, representative methods, devices, and materials are herein described. 
     Unless specifically stated, terms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. Likewise, a group of items linked with the conjunction “and” should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as “and/or” unless expressly stated otherwise. Similarly, a group of items linked with the conjunction “or” should not be read as requiring mutual exclusivity among that group, but rather should also be read as “and/or” unless expressly stated otherwise. 
     Furthermore, although items, elements or components of the disclosure may be described or claimed in the singular, the plural is contemplated to be within the scope thereof unless limitation to the singular is explicitly stated. The presence of broadening words and phrases such as “one or more,” “at least,” “but not limited to” or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent. 
     As a final matter, specific dimensions for various parts or aspects of the present invention, or embodiments thereof, may be provided. It will be understood however, that these dimensions are provided for illustrative purposes only and that dimensions could vary depending on the needs of the user, the task to be performed and/or the embodiment of the present invention being used. For example, depending on the size of the shaft to be removed, the transmission in which the shaft is housed and/or the size of the jack to be housed in the present invention, all diameters and dimensions disclosed herein could vary. 
     Referring now to  FIGS.  1 - 4   , an embodiment of the present invention includes an upper housing  2 , a lower housing  4 , a first and second handle  6  and a base  8 . The shown embodiment further includes a viewing window  10 . As can be seen, a lower end  2   b  of the upper housing  2  may be attached to an upper end  4   a  of the lower housing  4  by means of fasteners such at the depicted bolts  12 . In alternate embodiments, however, the upper housing may be attached to the lower housing by any means generally known. It is preferable to attach the upper housing to the lower housing in a removable fashion. The shown embodiment of the present invention further incudes a base  8  that is attached to a lower end of the lower housing. In the shown embodiment, the base  8  is permanently affixed by means of welding. In alternate embodiments, the base could be integrally formed as part of the lower housing  4  or alternatively could be removably attached by means generally known in the art. 
     Referring now to  FIGS.  3 A-D , the lower housing can be more clearly seen. The lower housing includes a first end  4   a , which is also referred to as the upper end, and a second end  4   b , which is also referred to as the lower end. In the shown embodiment, the lower housing  4  has a cylindrical shape that has an inner surface  7  having an inner diameter  14  and an outer surface  9  having an outer diameter  16 . In the shown embodiment, the viewing window  10  is disposed in the lower housing that is adjacent to the second or lower end  4   b . In the shown embodiment, the viewing window is generally square shaped but in alternate embodiments, the viewing window could be located anywhere on the lower housing and could have any number of shapes or sizes. In at least one embodiment, the lower housing includes a light source that will illuminate the area inside of the viewing window to aid the user&#39;s vision. 
     The lower housing  4  further includes a notch  18  disposed in the first or upper end  4   a  that extends downwardly towards the second or lower end  4   b . In the shown embodiment, this notch  18  is generally U shaped and has a width of approximately 0.7 inches and a length of approximately 2.3 inches. As will be discussed in association with  FIGS.  4 A-E  below, this lower housing notch  18  corresponds to a similar notch disposed in the upper housing. 
     Referring now to  FIGS.  4 A-E , the upper housing  2  will be discussed in further detail. The upper housing includes a first end  2   a , which is also referred to as the upper end, and a second end  2   b , which is also referred to as a lower end. In the shown embodiment, the upper housing  2  has a generally cylindrical cross sectional shape, having an inner surface  5  with an inner diameter  24  and an outer surface  3  having an outer diameter  26 . In at least one embodiment, the inner diameter  24  is slightly greater than the lower housing&#39;s outer diameter  16  so that the upper housing&#39;s lower end  2   b  may slide over the lower housing&#39;s upper end  4   b . Once in place, the upper housing  2  may be secured to the lower housing  4  by means of fasteners  12 , clamps or any other means generally known in the art. 
     The upper housing  2  includes a notch  20  that is defined in the lower end  2   b  and extends upwardly towards the upper end  2   a . Like the lower housing notch  18 , the upper housing notch  20  may have any shape that is generally known, including a U shape. Preferably, but not necessarily, the shape of the upper housing notch  20  and the lower housing notch  18  will be the same. In the shown embodiment, the upper housing notch  20  has a width of approximately 0.60 inches and a length of approximately 0.8 inches. As can be seen in  FIG.  2   , when the upper housing  2  is placed on and secured to the lower housing  4 , the upper housing notch  20  slides over the lower housing notch  18  to form an access port  21  that can be used to insert a power source, which can comprise a hydraulic hose or an electric cord (neither shown) that can be connected to the hollow body jack (No.  61  in  FIG.  8   ) that is housed in the lower housing  4 . Thus, the exact dimensions of the upper housing notch  20  and lower housing notch  18  can vary to provide the access port  40  with dimensions that are sufficient to accommodate the size of the hose (not shown) being used to power the hollow body jack. 
     In one embodiment, the upper housing  2  includes a generally flat surface  22  that is formed in the upper housing&#39;s outer surface  3  at a point that is adjacent to and surrounding the upper housing notch  20 . This flat surface  22  allows the hydraulic hose to be inserted into the access port  21  without interference from the outer surface  3 . In the shown embodiment, the flat surface surrounds each of the edges of the notch. In alternate embodiments, however, the flat surface  22  need not surround the entirety of the notch but could instead simply surround portions thereof such as along the lengths of the notch that extend from the lower end  2   b  towards the upper end  2   a.    
     In at least one embodiment, the upper housing further includes a cap  30 . As shown, the cap has an inner diameter  32  and an outer diameter  34 . In one embodiment, the inner diameter is approximately 2.5 inches and the outer diameter is approximately 4.5 inches. The cap may be secured to the upper housing&#39;s upper end  2   a  by permanent or removable means. In the embodiment shown in  FIG.  4 A , the cap  30  is welded to the inner surface  5  at a point that is adjacent to the upper housing&#39;s upper end  2   a . In alternate embodiments, however, the inner surface  5  and the cap  30  could be provided with corresponding threading to allow the cap to be screwed onto the upper housing&#39;s upper end  2   a . The cap serves as the upper surface of the upper housing  2  while the inner diameter  32  forms a jack opening  36  that is adapted to allow the piston of the hollow body jack (shown as  66  in  FIGS.  8 - 9   ) to rise above the cap and/or to retract below the cap as the jack is actuated to remove the propeller shaft. 
     Referring now to  FIGS.  5 A-C  and  6 , the inner guide conduit system  40  is shown. The guide support conduit system  40  comprises a central conduit member  42  and at least one support member  44 . In the shown embodiment, the support member  44  has a first end  45  that extends around the entire circumference of the central conduit  42  and second end  49  that is carried by the lower housing  4 . In the shown embodiment, the support member has a frustroconical cross sectional shape. In alternate embodiments, the support member may be disposed on or around only a portion of the central conduit  42  and may have any number of shapes. In one embodiment the support member  44  comprises two separate members—an outer support member  46  and an inner support member  48 . In this embodiment, the outer and inner support members are disposed along the central conduit member  42  such that the outer support members are located adjacent to the ends  42   a - b  of the central conduit and the inner support members are located closer to the midpoint of the central conduit. In alternate embodiments, the support member  44  could be a single member. 
     In the shown embodiment, the support member  44  is disposed on the central conduit  42  such that the support member&#39;s inner diameter  50  is located closer to the end  42   a  of the central conduit  42  than the outer diameter  52  is. While not necessary, this arrangement is preferable because the support member&#39;s angled surface  47  provides a surface that may be easily welded to the inner surface  5  of the upper housing  2 . In the shown embodiment, the present invention includes two support members for additional stability. In this embodiment, the support members are generally disposed adjacent to the ends  42   a - b  of the central conduit. In alternate embodiments, however, any number of support members that are spaced at any point along the length of the central conduit may be used. In the shown embodiment the second end  49  of the support member  44  is carried by the lower housing&#39;s inner surface  7 . 
     Referring now to  FIGS.  7 A-B , the base  8  may be more clearly seen. In the shown embodiment, the base  8  comprises a ring shaped disc having an inner diameter  60  which forms a base opening and an outer diameter  62 . In this embodiment, the inner diameter is preferably, but not necessarily, the same as the inner diameter  14  of the lower housing&#39;s lower end  4   b . In alternate embodiments, the base&#39;s inner diameter  60  can be greater or less than that of the lower housing&#39;s lower end  4   b . In the shown embodiment the base&#39;s outer diameter  62  is greater than the outer diameter  16  of the lower housing&#39;s lower end  4   b , such that the base provides additional stability and support and distribute more evenly the amount of force that the present invention exerts on the shaft housing from which the shaft is being removed. In the shown embodiment the base  8  is permanently attached to the lower housing&#39;s lower end  4   b . In alternate embodiments, however, the base could be integral with the lower housing or removably attached thereto by generally known means. 
     Referring now to  FIG.  8   , a cross sectional view of a fully assembled embodiment of the present invention can be seen. A hollow bodied jack  61  may be placed into the jack chamber  63 , which is defined by a portion of the upper housing  2 , a portion of the lower housing  4  and a portion of the upper end of the inner guide conduit system  40 . When the jack  61  is placed in the upper end  4   a  of the lower housing  4 , the jack&#39;s lower surface  62  is supported by the inner guide conduit system  40 . Preferably, but not necessarily, the inner diameter  14  of the lower housing is just slightly larger than the diameter of the jack such that there is very little room for the jack  61  to shift once placed in the lower housing  4 . Once the jack is in place, the lower end  2   b  of the upper housing  2  may slide over top of the lower housing&#39;s upper end  4   a . Preferably, but not necessarily, the dimensions of the upper housing are such that once the upper housing  2  is secured to the lower housing  4 , the cap  30  will contact or be adjacent to the jack&#39;s upper surface  64 . In this embodiment both the upper housing and the lower housing prevent the jack from shifting positions while enclosed in the present invention. Preferably, but not necessarily, the inner diameter  14  of the lower housing  4  is such that the lower housing&#39;s inner surface  7  is in contact with or adjacent to the outer surface  65  of the jack  61 . As previously discussed, the cap&#39;s inner diameter  32  forms a jack opening  36  that allows the jack&#39;s piston  66  to rise and fall while in use. 
     A viewing chamber  67  is defined by at least a portion of the lower housing  4  and a portion of the inner guide conduit system  40 . Access to the viewing chamber is provided by the viewing window  10  that is defined in the lower housing  4  so that the end user may view the shaft  80  being removed as well as physically manipulate the shaft to be removed. 
     Referring now to  FIG.  9    the operation of the shown embodiment of the present invention will be described. One of the steps during use of the present invention is to attach a shaft coupler  74  to the shaft  80  to be removed. Typically shafts such as drive shafts and/or propeller shafts have a threaded end  82 . Therefore, in at least one embodiment, the shaft coupler  74  comprises a threaded female to female type coupler having a threaded inner surface that may interconnect two shafts, each having at least one male type threaded end. Either before or after the shaft coupler  74  is attached to the shaft  80 , the base  8  may be placed over the shaft  80  such that the base  8  sits on or adjacent to the circumference of the shaft opening  84  that is defined in the shaft/transmission housing  86 . Once in place, an extension shaft  70  may be inserted into and through the hollow body jack  61  and through the internal guide conduit system  40 . Once the extension shaft is in place, it may be connected to the shaft coupler  74 . An extension rod securing member (also referred to as a shaft securing member)  72  may then be used to secure the extension shaft  70  to the jack&#39;s piston  66 . 
     Once the present invention is in place and the shaft to be removed  80  is secured to the piston of the hollow body jack  61 , the jack can be actuated by means of a power source, which may comprise a hydraulic hose (not shown) or and electric cord (not shown). Once actuated, the jack&#39;s piston  66  is rise upwardly through the jack opening  36  and above the cap and/or upper surface  30  of the upper housing. Because the extension shaft  70  is secured at a first end to the propeller shaft  80  by means of the coupler  74  and secured at a second end to the piston  66  by means of the extension rod securing member  72 , actuation of the jack  61  will cause the piston to lift the propeller shaft  80 , thus breaking any seal that has developed between the shaft  80  and the housing  86  and/or the shaft opening  84  defined in the housing. 
     Once the seal has been broken, the shaft securing member  72  may be removed from the extension shaft (also referred to as an extension rod)  70 . Next, the present invention can be lifted up and off of the extension shaft and the propeller shaft  80  may be removed from the shaft opening  84  simply by pulling the extension shaft upwardly and away from the shaft opening. 
     While the present subject matter has been described in detail with respect to specific exemplary embodiments and methods thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and/or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art using the teachings disclosed herein.