Abstract:
A rotary honing tool includes a rotatable body member mounted on a shaft and having attached rotatable honing arms as well as a band or collar fitted about the body. The collar is engaged with the body by means of a lug on the collar fitted into a channel on the outside face of the cylindrical body. The collar may be rotatably displaced to control radial extention of the honing arms.

Description:
BACKGROUND OF THE INVENTION 
     In a principal aspect, the present invention relates to a rotary honing tool comprised of honing blades mounted on arms projecting from a rotating body. The arms are biased outwardly for engagement with the cylindrical wall of an engine cylinder. More particularly, the invention relates to a mechanism for controlling the radial position of the honing arms. 
     The use of a cylinder honing tool to polish or hone the cylinder of an engine block has been facilitated by the use of various special tools. U.S. Pat. No. 2,736,146 for a Cylinder Hone issued Feb. 28, 1956 discloses a tool that has such use. The tool disclosed in U.S. Pat. No. 2,736,146 has been popular and generally, commercially successful. U.S. Pat. No. 2,736,146 is incorporated herewith by reference in its entirety as disclosing a prior art construction. 
     One of the features of the tool depicted in U.S. Pat. No. 2,736,146 is the use of a collar that controls or limits the radial position or outward extent of the honing arms to which the cylinder honing stones are attached. To adjust this collar and thus adjust the radial position or limit of outward radial movement the honing stones, it is necessary to release a screw that holds the collar in position and then manually rotate the collar followed by resetting the screw. This screw and collar adjustment is often time consuming and troublesome especially in the event that a screwdriver or similar tool is not available to facilitate the loosening and retightening of the screw holding the rotatable collar. Thus there has developed the need for an improved mechanism which will enable engagement and release of the collar which holds cylinder hone support arms. 
     SUMMARY OF THE INVENTION 
     Briefly the present invention comprises a rotary honing tool of a type that includes a rotary drive shaft, a body mounted on the drive shaft with a center line axis coincident with the drive shaft axis, and at least one honing support arm extending through a radial guide channel in the body. A biasing element engages and biases the honing arm radially outwardly in the channel. The improvement of the invention comprises an adjustable collar rotatably mounted on the body. The collar includes at least a first and a second detent position which, respectively, permit the hone arm, or arms, to extend radially outwardly to engage the cylinder walls or, alternatively, to hold the hone arms tightly in a position of non-engagement closely aligned with the rotation axis of the tool. The collar thus includes an inwardly projecting tab which fits within a rotational guide slot or channel defined in outside surface of the body. This tab may engage into any one or more detent recesses in the channel and it is also cooperative with an axial channel of the body parallel to the shaft axis that is also provided in the outer surface of the body. The axial channel facilitates assembly of the collar to the body when axially sliding the collar onto the body. The collar further includes inwardly projecting fingers or lips designed to engage the honing arms and hold them in their retracted or inward position aligned with the axis of the tool. Upon rotation of the collar, the fingers may disengage from the arms permitting them to move outwardly to their released position of engagement for honing the cylinder walls. 
     Thus it is an object of the invention to provide an improved honing tool having a collar that may be easily and manually actuated to control the angular relationship of the arms projecting from the honing tool. 
     It is a further objection of the invention to provide a honing tool which is rugged, inexpensive, and constitutes a low cost modification of prior art tools and which is economical to manufacture and easy to use. 
     These and other objects, advantages, and features of the invention will be set forth in the detailed description that follows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     In the detailed description that follows reference will be made to the drawing comprised of the following figures. 
     FIG. 1 is an isometric view of the honing tool of the invention wherein the collar is positioned to retain the honing arms inwardly on the body of the tool; 
     FIG. 2 is a side elevation of the tool of FIG. 1; 
     FIG. 3 is a cross sectional view of the tool of FIG. 2 taken along the line  3 — 3 ; 
     FIG. 4 is as cross sectional view of the collar in combination with the body member taken along the line  4 — 4  of FIG. 3; 
     FIG. 5 is an exploded isometric view depicting the body member and collar for the tool; 
     FIG. 6 is a side elevation of the body and collar shown in FIG. 5; and 
     FIG. 7 is a cross sectional view of the body member of FIG. 6 taken along the line of  7 — 7 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The cylinder hone includes an axial drive shaft  10  that defines a rotation axis  12 . The drive shaft  10  is threadably connected at its outer end  14  to a connector  16 . The connector  16  is adapted to be connected to a drive mechanism such as a power drill or the like to effect rotation of the shaft  10 . The opposite or inner end of the shaft  10  is connected to a body member  18 . A cone member  20  is concentrically mounted on the shaft  10  with a coil spring  22  biased by an adjusting nut  24  threaded on the outer end  14  of the shaft  10 . First, second and third hone arms  26 ,  28 , and  30  are pivotally attached at their inner end to the underside of the cone member  20  by insertion into slots such as slot  32  defined on the underside of the cone member  20 . Each of the arms  26 ,  28 , and  30  fit through separate longitudinal channels  34 ,  36 , and  38  defined in the body member  18  at equally spaced positions about the axis  12 . The channels  34 ,  36 , and  38  receive the arms  26 ,  28 , and  30 , respectively, and provide a guide for the arms  26 ,  28 ,  30  as well as a means for retaining the arms  26 ,  28 , and  30  and driving the arms  26 ,  28 , and  30  by rotation of the shaft  10  about the axis  12 . 
     The arms  26 ,  28 , and  30  are held in position within their respective channels  34 ,  36 , and  38  by means of a band or collar  40 . The outer end of each of the hone arms  26 ,  28 , and  30  has a hone or honing stone  42  in a housing  43  pivotally attached thereto. The hones  42  include a face surface  44  adapted to engage against the walls of a cylinder upon the rotation of the shaft  10  for polishing or honing the inside surface of the cylinder. 
     The present invention relates to the construction of the band or collar  40  alone and in combination with the elements comprising the cylinder hone. The cylinder hone as described is substantially as set forth in U.S. Pat. No. 2,736,146 but for the addition or substitution of the band or collar  40  in the embodiment of the present invention in place of ring  54  as depicted in U.S. Pat. No. 2,736,146. 
     More specifically the band or collar  40  is formed from a glass filled nylon material; typically a 30 percent glass filled nylon. The band or collar  40  is cylindrical in shape and includes a through passage  50 . The band or collar  40  has a generally uniform diameter substantially equal to the outside diameter of the body member  18  so that it may smoothly slide on and be rotated with respect to the cylindrical body member  18 . The band or collar  40  further includes first, second, and third inwardly radially projecting, equally spaced lips  52 ,  54 , and  56 . The lips  52 ,  54 , and  56  have a width dimension which is less than the width of channels  34 ,  36 , and  38  so that the lips  52 ,  54 , and  56  may fit over as well as slide into the channels  34 ,  36 , and  38 . 
     The collar  40  further includes a first sidewall slot  58 , a second side wall slot  60 , and a third side wall slot  62  adjacent respectively to the lips  52 ,  54 , and  56 . The slots  58 ,  60 , and  62  have a width which exceeds the width of the hone arms  26 ,  28 , and  30  so that the hone arms  26 ,  28 , and  30  may fit through the slots  58 ,  60 , and  62  and move radially outward limited only by the upper edge of each of the slots  58 ,  60 ,  62 , for example by the upper edge  64  of the slot  58 . Thus the slots  58 ,  60 , and  62  are equally spaced about the periphery of the band or collar  40 . When the collar  40  is in the proper rotation orientation or position as rotated about the axis  12 , the hone arms  26 ,  28 , and  30  may extend outwardly radially from the cone member  20  through the channels  34 ,  36 , and  38 . 
     In addition to the channels  34 ,  36 , and  38 , the body member  18  includes a partially circumferential slot or channel  70  which is connected with a longitudinal axial slot  72 . Axial slot  72  as well as channel  70  are on the outside face or surface  71  of the body member  18 . Axial slot  72  is generally parallel to the axis  12 . The peripheral channel or slot  70  is generally perpendicular to the axis  12  and extends partially about the circumference of the body member  18  between two channels, for example, channels  36  and  38 . 
     The channel or slot  70  further includes a first detent or depression  74  at one end and a second detent or depression  76  at its opposite end. The detents  74  and  76  are adapted to receive an inwardly extending lug, tab, or guide member  78  on the inside surface  41  of the collar  40 . The lug  78  is positioned adjacent to the lip  56  and generally adjacent one of the slots  60  so that the collar  40  may be assembled onto the body  18  by sliding the collar  40  axially downwardly on the body  18  along the axis  12  so that the lug  78  will fit into the axial slot  72 . The depth of the axial slot  72  is less than the depth of the detents  74  and  76 . Thus the lug  78  will ride over the face or surface of the axial slot  72  and fall into the detent  74  to be retained thereby. The depth of the channel  70  between the detents  74  and  76  is lesser then the depth of the detents  74  and  76  to provide a “feel” upon rotation of the band or collar  40  about the axis  12  as depicted in FIG.  6 . The shape of the channel  72  may thus be customized to provide desired “feel” and detect retention. 
     With the construction so described, the collar or band  40  may be inserted over the body  18  by axial movement of lug  78  in slot  72  and lips  50 ,  54  and  56  in channels  34 ,  36 , and  38 . Then collar  40  may be rotationally positioned into one of the two detent positions  74  or  76  to alternately hold the hone arms  26 ,  28 , and  30  inwardly by means of the lips  50 ,  54 , and  56  or alternately to permit the arms  26 ,  28 , and  30  to expand outwardly through the slots  58 ,  60 , and  62 . 
     Adjustment of the hone arms  26 ,  28 , and  30  may then be effected by gripping the arms  26 ,  28 , and  30  and moving them inwardly while rotating the band or collar  40  to engage the lips  52 ,  54 , and  56  therewith. Alternatively the hone arms  26 ,  28 ,  30  may be released and expand outwardly upon rotation of the band or collar  40  so that the channels  58 ,  60 , and  62  will receive the arms  26 ,  28 , and  30 . 
     With the construction of the invention it is therefore possible to adjust the position of the hone arms  26 ,  28 , and  30  and their angular displacement from the axis  12  by merely rotating the collar  40 . In the embodiment shown there are only two positions for the hone arms  26 ,  20 ,  30 ; namely the position defined by lips  52 ,  54 , and  56  and the position defined by channels  58 ,  60 , and  62 . It is possible to provide additional “steps” for control of the displacement of those arms  26 ,  28 ,  30 . Thus there are alternative constructions to the invention. The invention is therefore to be limited only by the following claims and equivalents thereof.