CROSS REFERENCE TO RELATED APPLICATION 
     This application is a division of U.S. patent application Ser. No. 09/132,310, which was filed on Aug. 11, 1998 now U.S. Pat. No. 6,158,163. 
    
    
     TECHNICAL FIELD 
     This invention relates to the art of fish-bite indicators. 
     BACKGROUND ART 
     The present invention is relates to a fish-bite indicator comprising an arm that is pivotally mounted on a pivotal mount at one of its ends and has a fishing line engagement element at the other. A resilient clement is provided at the pivotal mount to vary the force with which the engagement element acts on the line, and the resilient element acts on one of two parts that can be selectively rotated relative to one another to vary the torsion force exerted by the resilient element. 
     One such construction that has been proposed has ratchet element between the two parts, making it a relatively complex and expensive construction. 
     It is the aim of the present invention to obviate one or more of these disadvantages. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to a fish-bite indicator having two parts that are relatively movable about an axis of rotation and are held at a selected one of a plurality of available relative angular positions by mutually engaging portions, at least one of which has a leading face and a trailing face that extend generally parallel to the axis of relative rotation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     An example of a fish-bite indicator, in accordance with the present invention, will now be described with reference to the accompanying drawings in which: 
     FIG. 1 is a view from one side of angling apparatus including a fish-bite indicator made in accordance with the present invention; 
     FIG. 2 shows a perspective view from the other side and above the apparatus shown in FIG. 1, with further parts of the apparatus in view; 
     FIG. 3 shows an axial sectional view through a part of the apparatus shown in FIG. 2; 
     FIG. 3 a  shows a sectional view taken along line III in FIG. 3; 
     FIG. 4 shows an exploded view of the part of the apparatus shown in FIG. 3; 
     FIG. 5 shows an end view of a component viewed in the direction V indicated in FIG. 3; 
     FIG. 6 shows a portion of the component shown in FIG. 5 viewed in the direction VI indicated in FIG. 5; 
     FIG. 7 shows a portion of the component shown in FIG. 5 viewed in the direction VII indicated in FIG. 5; 
     FIG. 8 shows an end view of a further component viewed in the direction VIII indicated in FIG. 3; 
     FIG. 9 shows a sectional view of the component shown in FIG. 8 taken along the line IX indicated therein; and 
     FIG. 10 shows a perspective view of the part shown in FIG. 3 with further portions thereof shown more fully. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the angling apparatus shown in FIG. 1, there is shown a bank stick  70  on the upper end of which is mounted a bifurcated electronic bite indicator  72 . A fishing rod  74  is seated within the bifurcations of the electronic bite indicator  72 . 
     A mounting plate  76  is secured between the bite indicator  72  and the top of the ban stick  70 , and to that mounting plate  76  is secured a fish-bite indicator  100  in the form of a generally rigid arm  102 , which is connected at one end to a pivot  104 , the other end of the arm  102  being provided with a head  88 . A fishing line  82  is held between a pair of leg portions  18  and  24  of the head  88  so that the fishing line  82  traces out a V shape between the bite indicator  72  and one of the rings  84  (the others not being shown) of the fishing rod  74 . 
     A slideable weight  106  is attached to the arm  102  and can be slid backwardly or forwardly along the arm to adjust the tension of the line  82 . FIG. 1 provides a diagrammatic representation of three different, possible positions of the bite indicator  100 . For two of these positions, the fishing line  82  is shown as a broken line. 
     If the angler reacts to a bite indicated by one or both of the bite indicators  72  and  100  and makes a strike, the line  82  is readily released from between the legs  18  and  24 . 
     FIG. 2 shows the apparatus from the other side and also shows a reel  86  of the rod  74 . It also shows the commencement of a strike insofar as the rod  74  has been lifted clear of the bite indicator  72 , and the line  82  is about to be released from the head  88  at the end of the fish-bite indicator  100 . 
     FIGS. 3 to  10  show the details of the pivot  104  illustrated in FIGS. 1 and 2. The pivot comprises a generally cylindrical housing  120 , which is provided with a knurled portion  122  at an outer end thereof to assist the user in grasping and rotating the latter. The housing  120  surrounds an axially-extending, hollow shaft  124 , an outer end of which is closed by means of a flanged plug  126  having an annular a groove  128  extending around the outside of this flange. An open frictional ring  130  is seated within this groove  128  so that a portion of the ring  130  protrudes outwardly therefrom and contacts an inner face of the cylindrical housing  120 . 
     The shaft  124  is integral with a mount  132 , which has a generally circular base portion  134  and a further portion  136 , which is generally L-shaped in the axial section shown in FIG. 3. A pivot pin  138  has respective ends received in respective holes of the two portions  134  and  136 . The pin  138  extends through a through hole  140  provided in the end of a pivoted connector member  142  to which is secured the pivot arm  102  shown in FIGS. 1 and 2. 
     An axially-extending helical spring  144  is enclosed within the housing  120 , and has one end  146  abutting against an abutment  148  provided on the interior of the housing  120 , and another end which extends outwardly from the housing  120  through a slot  150  provided therein and thence in an axial direction to a portion  152  of that end of the spring  144  which engages the connecting portion  142  at a position thereof which is spaced from the pivot pin  138 . 
     The housing  120  and the base  134  inter-engage with one another by respective castellations  154  and  156 , as shown more clearly in FIG. 3 a.    
     FIGS. 4 and 10 show more clearly how the mount  132  is made integral with an attachment portion  170 , which has a female part of a dovetail joint  172  to enable the pivot  104  to be connected to the plate  76  shown in FIGS. 1 and 2. FIG. 10 also shows how the spring assembly acts on the arm  102  also shown in FIGS. 1 and 2. 
     It will be appreciated from FIG. 3 that the spring  144  acts on the connector member  142  to urge the latter to rotate about the pin  138 . This may be used to increase the downward pull of the head  88  on the line  82  or to counter the torque already applied by the weight  106 . It, therefore, can be used to provide a fine adjustment to this torque. Alternatively, the weight  106  may provide the fine adjustment relative to the spring assembly. This adjustment itself may be varied by rotation of the housing  120  relative to the base  134 . To effect such rotation, the housing  120  is first moved axially and outwardly away from the base  132  to disengage the respective castellations  154  and  156 . A shoulder  158  provided on the inside of the housing  120  will abut the flange of the plug  126  if the housing  120  is pulled out too far. In this way, the plug  126  acts as a stop against accidental removal of the housing  190 . 
     At least one of the castellations  154  or  156  has leading and trailing faces, such as the leading and trailing faces shown at  153  and  155  on castellation  154  in FIG.  5 . It will be appreciated that these faces extend in the direction of the axis about which the base and housing parts rotate with respect to each other. 
     The housing  120  may now be rotated about the axis of the pivot to increase or decrease the force applied by the spring  144  to the connector member  142 . The selected axial rotation can be maintained by re-engaging the castellations  154  and  156  of the housing  120  and the base  134  (although the ones actually labeled  154  and  156  will not now be engaging one another). 
     In a zero setting of the housing  120 , the relative positions of the housing and base are such that the end  146  of the spring  144  is free to move between the abutments  148  and  162  without any force being applied by the spring to the connecting member  142 . In this way a zero or a generally optimum setting can be made by means of the weight  106  without interference from the spring, and then a finer adjustment can be made by means of the spring assembly by subsequent rotation of the housing  120 . 
     Many variations and modifications to the illustrated indicator will readily occur to the reader of ordinary skill in the art without taking it outside the scope of the present invention. For example, foam or rubber could perform the function of the spring  144 .
A fish-bite indicator ( 100) comprises an arm ( 102) pivotally mounted on a pivotal mount ( 104) at one of its ends and which has a fishing line engagement element ( 18 and 24) at the other. A helical spring ( 144) is provided at the pivotal mount ( 104) to vary the force with which the engagement element ( 18 and 24) acts on the line ( 82), the spring ( 144) acting on one of two parts ( 120 and 134), which can be selectively rotated relative to one another to vary the torsional force exerted by the helical spring ( 144). The two parts ( 120 and 134) are held at a selected one of a plurality of available relative angular positions by mutually engaging castellations ( 154 and 156).