Abstract:
A shearing tool has two blades which are pivoted together by a pivot in conjunction with a nut. The pivot has a head, and a shank which is provided with a lubricant cell and plural channels. The lubricant cell is in communication with the exterior of the shank area, the channels enabling the lubricant contained in the lubricant cell to lubricant the two blades. The lubricant cell includes a depressed oiling region for containing oil therein during re-lubrication. The shank has outer threads to mesh with inner threads of the nut.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     This invention relates to bolts for use in connection with joining pivoting members, and more particularly to a pivot bolt with lubricating features  
         [0002]      FIG. 1  shows a shearing tool  10  in accordance with the prior art, wherein the tool comprises two blades  12 , two handles  14  fastened with the blades  12 , and a pivot  14  for pivoting together the blades  12  in conjunction with a nut (on the reverse side of the tool, not shown in the drawing). In order to enable the blades  12  to pivot about the axis  18  in the directions of arrow  20 , it is necessary to apply lubricant from time to time to the area at which the two blades  2  are pivoted together. However, such an application of the lubricant can be ineffective at best in reducing friction between the two blades  12 . This is due to the fact that the lubricant so applied does not dwell steadily on the pivoting portion of the shearing tool. In other words, the conventional practice of the lubricant application merely results in the waste of lubricant. The lubricant will quickly disperse and spread along the blades away from the pivoting region.  
       SUMMARY OF THE INVENTION  
       [0003]     In accordance with the invention, a lubricating pivot bolt is provided for use with connection of pivoting members. The pivot bolt is provided with a lubricant cell with plural channels to distribute the lubricant to the mating areas of the pivoting members in the area of the pivot point, to effectively lubricate the pivoting members, thereby resulting in reduction in friction between the members. A lubricant receiving well is provided at the lubricant receiving position, for ease of re-supply of lubricant.  
         [0004]     Accordingly, it is an object of the present invention to provide an improved pivoting member joining device.  
         [0005]     It is a further object of the present invention to provide an improved pivot point nut member with improved lubricant delivery and re-supply features.  
         [0006]     It is yet another object of the present invention to provide an improved oiler bolt for use with pivoting blades, scissor-type moving members and the like.  
         [0007]     It is a further object of the present invention to provide an improved lubricant bolt for use in connecting pivoting blades of a shearing tool, trimmers, or the like.  
         [0008]     The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is a view of a shearing tool using a connecting bolt in accordance with the prior art;  
         [0010]      FIG. 2  is an exploded view of a pivot lubricating bolt in accordance with the present invention;  
         [0011]      FIG. 3  is a sectional view taken along line  3 - 3  of  FIG. 2 ;  
         [0012]      FIG. 4  is an exploded view of another embodiment of a pivoting lubricating bolt in accordance with the invention;  
         [0013]      FIG. 5  is a sectional view of the embodiment of a pivoting lubricating bolt as shown in  FIG. 4 , taken along line  5 - 5 ;  
         [0014]      FIG. 6  is a top sectional view illustrating placement of the lubrication channels; and  
         [0015]      FIG. 7  is a top sectional view showing alternative lubrication channel placement. 
     
    
     DETAILED DESCRIPTION  
       [0016]     As shown in  FIGS. 2 and 3 , a pivot lubricating bolt  30 , illustrated in connection with use on a shearing tool, such as hedge trimmers, pruning tools or the like, a pivot lubrication bolt  30  is employed to join the two blades  32  of a shearing tool, for example. The blades  32  are provided with pivoting holes  34 ,  36  for receiving the pivot lubricating bolt  30 . The pivoting hole  34  of the first blade is suitably round, whereas the pivoting hole  36  of the second blade is suitably rectangular.  
         [0017]     The pivot lubrication bolt  30  is characterized by a head, and a shank. The shank is provided with a male threaded portion  38 , a round segment contiguous to the head, a rectangular mid-segment located between the round segment and the male threaded portion, and a lubricant cell  40  with an open end extending through the head. The lubricant cell  40  is provided with two or more channels  42  in communication between the interior of the cell  40  and with the exterior of the shank. The lubricant cell  40  is provided with an elastic or biasing member  44 , a covering member  46 , and a stop member  48 . The elastic member  44  is suitably a coil spring in the preferred embodiment. The covering member  46  is of a spherical construction and is located at the open end of the lubricant cell  40 . Covering member may comprise a ball bearing, for example. The elastic member  44  and the covering member  46  are retained in the lubricant cell  40  by the stop member  48  which seals off the open end of the lubricant cell  40 .  
         [0018]     The covering member  46  and stop member  48  are suitably positioned centrally of the bolt, within a well portion  50  defined in the face of the bolt. The well is suitably formed as a bevel, so as to define a depth  52  between the top of the covering member and the outer face of the bolt  30 .  
         [0019]     The first blade and second blades  32  are held together in pivoting relation by the pivot lubrication bolt  30  in conjunction with a nut  54  and two washers  56  serving to reduce friction between the blades and the nut.  
         [0020]     In use, as the covering member  46  is pressed against the coil spring  44 , a gap is created between the covering member  46  and the stop member  48  in view of the covering member  46  being partially moved out of contact with the stop member  48 . A lubricant, such as oil, for example, may then be injected into the lubricant cell  40  via the gap. The well portion  50  provides a holding area to receive the lubricant temporarily, until the lubricant may pass by the covering member into the lubricant cell  40 . This enables an easier re-supply of the lubricant cell, without the likelihood that the lubricant will spill beyond the extent of the bolt, especially in the case where the lubricant supply nozzle is not precisely inserted into the opening of the stop member.  
         [0021]     In use of the tool, the blades  32  are supplied the lubricant via the channels  42  of the lubricant cell  40 . The plural channels are suitably arranged radially about the pivot axis so as to provide the lubricant where desired for maximum effect. The preferred embodiment employs  2  such channels, but more may be employed in different applications other than the illustrated shear. For example, in a configuration have  3  or  4  such channels, the channel diameter may be reduced to ensure a slower feed rate of the lubricant. The channels may be regularly spaced about the bolt, or, may be positioned irregularly, if the particular configuration of the pivoting members is such as to desire greater lubricant delivery in one region relative to another.  
         [0022]     As shown in  FIGS. 4 and 5 , a second embodiment of the pivot lubrication bolt comprises a pivot  58  which has a corresponding configuration to that of the bolt  30  described hereinabove, but with a different construction of the lubricant cell. The lubricant cell  60  is receiving in the body of the bolt and is provided with an inner threaded potion  62  which is engaged with a plug member  64 , the plug being provided at the outer end with a slotted head  66 .  
         [0023]     In this embodiment, before the lubricant is injected into the lubricant cell  60 , a screw driver is used to turn the plug  64  such that the screw driver is engaged with the slotted head  66  of the plug  64 . The plug is removed, and lubricant is added to the lubricant cell. The plug is then re-inserted into the opening. In use, to cause lubrication to be dispensed via the lubrication channels  42 , a screwdriver or other suitable device is inserted into the slot  66 , and the plug  64  is rotated to cause it to move inwardly toward the bottom of the lubricant cell. This causes the lubricant to be forced out of the lubricant cell via the channels. The amount of lubricant thereby dispensed can be controlled by the amount of rotation of the plug  64 . This is particular useful in cases of using a lubricant which has a higher viscosity, and the lubricant suitably remains in the lubricant cell until the rotation of the plug member.  
         [0024]     While the illustrated slotted head is of the “−” type for use with the “−” type screwdriver, and “+” type head or hexagonal head or square drive head may also be employed, for example, for actuation by “+” type drivers or square or hex head drivers.  
         [0025]     The bolt  58  also employs the well portion  50  so as to provide a region to contain lubricant while refilling, to lessen the likelihood of spilling and to ensure that the lubricant will end up in the lubricant cell.  
         [0026]     As noted hereinabove, two or more lubrication channels  42  may be employed in either of the illustrated embodiments.  FIG. 6  is a top sectional view taken along line  6 - 6  of  FIG. 3 , showing a two channel configuration with the channels arranged on opposite sides of the bolt. Additional optional channels  42 ′ are shown in phantom.  FIG. 7  is a top sectional view showing a non-symmetrical channel arrangement.  
         [0027]     While the illustrated embodiment shows the lubrication bolt used in connection with a shearing tool, other uses include scissors, clamping type tools, such as pliers, for example.  
         [0028]     While plural embodiments of the present invention has been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its broader aspects. The appended claims are therefore intended to cover all such changes and modifications as fall within the true spirit and scope of the invention.