Background of the Invention
[0001] The present invention relates to an adjustable wrench.
 
            [0002] A wide variety of wrenches, spanners, and pliers have heretofore been disclosed.
               For example, U.S. Patent No. 3,916,735 to Evans discloses adjustable multiple purpose
               ratcheting wrenches. Nevertheless, the fastener still tends to have a loose contact
               with the ratcheting wrenches when a force is applied to loosen or tighten the fastener.
               In addition, the fastener cannot be speedily loosened or tightened. U.S. Patent No.
               5,551,322 to Mikic et al. discloses a speed wrench for speedily loosening or tightening
               fasteners. U.S. Patent No. 5,630,344 to Nammoto discloses a side-entry, ratcheted
               wrench assembly to conveniently and effectively loosen or tighten fasteners disposed
               in a difficult to access or reach location. U.S. Patent No. 5,630,345 to Ciccotelli
               discloses a plier having a hinged jaw piece which is pivotally attached to a support
               arm for adjusting the hinged jaw piece parallel relative to the other jaw, and the
               adjusting means is manually operated and is self-locking. Nevertheless, the jaws of
               the tools disclosed in these patents cannot provide an adequate clamping to the fastener
               between the jaws. More specifically, the corners of the fastener will be damaged if
               too loose, and operation of the tools is adversely affected if too tight.
 
            [0003] Therefore, there has been a long and unfulfilled need for an improved adjustable
               wrench which mitigates and/or obviates the above problems.
 
            Summary of the Invention
[0004] An adjustable wrench in accordance with the present invention comprises an elongated
               member including a first handle end and a second end, the second end including a fixed
               jaw and an engaging section formed thereon. The adjustable wrench further includes
               a movable jaw having a clamping section formed on a first end thereof and a second
               end pivotally connected to the engaging section of the elongated member. An adjusting
               means is mounted between the second end of the elongated member and the movable jaw
               to urge the movable jaw to pivot relative to the fixed jaw. An elastic means has a
               first end attached to the adjusting means to frictionally retain the adjusting means
               in position and a second end securely received in one of the elongated member and
               the movable jaw.
 
            [0005] In a preferred embodiment of the invention, the adjusting means includes a screw
               rod with a wheel formed on a mediate section thereof. A first pin is mounted in the
               movable jaw and includes a first transverse screw hole through which a first end of
               the screw rod extends. A second pin is mounted in the engaging section and includes
               a second transverse screw hole through which a second end of the screw rod extends.
               Preferably, the wheel includes a plurality of alternately disposed longitudinal ribs
               and longitudinal grooves, and the second end of the elastic means is received in one
               of the longitudinal grooves.
 
            [0006] In an embodiment of the invention, the movable jaw includes a compartment defined
               therein, and the elastic means is a hollow elastic tube having a first end received
               in one of the longitudinal grooves and a second end securely received in the compartment.
 
            [0007] In an alternate embodiment of the invention, the elongated member includes a compartment
               defined therein. The elastic means includes a rod having a first end and a second
               end securely received in the compartment, and an elastic member is received in the
               compartment to bias the rod to engage with one of the longitudinal groove.
 
            [0008] The engaging section of the elongated member may include a pair of spaced lugs having
               aligned holes defined therein for receiving the second pin.
 
            [0009] The second end of the movable jaw may include a pair of spaced wall members, in which
               the wall members include first aligned holes defined in a first section thereof for
               receiving a third pin and second aligned holes defined in a second section thereof
               for receiving the first pin. A recessed section is formed between the fixed jaw and
               the engaging section, and the recessed section includes a through hole through which
               the third pin extends.
 
            [0010] Other objects, advantages, and novel features of the invention will become more apparent
               from the following detailed description when taken in conjunction with the accompanying
               drawings.
 
            Brief Description of the Drawings
[0011] 
               
               Fig. 1 is an exploded perspective view of an adjustable wrench in accordance with
                  the present invention;
               Fig. 2 is a perspective view of the adjustable wrench in accordance with the present
                  invention;
               Fig. 3 is a top view, at an enlarged scale, showing the details of a head portion
                  of the adjustable wrench in accordance with the present invention;
               Fig. 4 is a view similar to Fig. 3, illustrating a modified embodiment of the adjustable
                  wrench in accordance with the present invention;
               Fig. 5 is a view similar to Fig. 3, in which the adjustable wrench is adjusted to
                  clamp a small bolt;
               Figs. 6 to 9 are schematic top views illustrating operation of the adjustable wrench;
                  and
               Fig. 10 is a schematic view illustrating application of the adjustable wrench in accordance
                  with the present invention.
 
            Description
[0012] Referring to the drawings and initially to Figs. 1 and 2, an adjustable wrench in
               accordance with the present invention generally includes an elongated member 10 having
               a first handle end 11 and a second end on which a fixed jaw 14 is formed. The fixed
               jaw 14 includes a clamping section 14 which will be described later. Also formed on
               the second end of the elongated member 10 is an engaging section 12 having a pair
               of lugs 123 formed thereon. The lugs 123 include a space defined therebetween and
               aligned holes 122 defined therein. A recessed section 13 is formed between the engaging
               section 12 and the fixed jaw 14. The recessed section 13 includes a recess 131 defined
               in each of two sides thereof and thus has a thickness smaller then that of the elongated
               member 10. The recessed section 13 further includes a transverse hole 1311 defined
               therein.
 
            [0013] The adjustable wrench further includes a movable jaw 20 having a first end on which
               a clamping section 21 is formed. The movable jaw 20 further includes a second end
               including a pair of spaced wall members 27 which, in turn, define a space 22 therebetween.
               The wall members 27 include aligned holes 221 defined in a first section end thereof
               for receiving a pin 23 therein and aligned holes 222 defined in a second section thereof
               for receiving a pin 24 therein.
 
            [0014] The adjustable wrench further includes an adjusting means 30 which, in turn, includes
               a screw rod 32 with a wheel 31 integrally formed on a mediate section thereof. The
               wheel 31 includes a plurality of alternately disposed longitudinal ribs 311 and grooves
               312. The adjustable wrench further includes an elastic means. In an embodiment of
               the invention, the elastic means 40 has a first end 41 and a second end 42 which will
               be described later.
 
            [0015] In assembly, still referring to Figs. 1 and 2 and further to Fig. 3, the second end
               42 of the elastic member 40 is inserted into a compartment 15 (Fig. 3) defined in
               the movable jaw 20. A pin 25 having a transverse screw hole 251 is mounted in the
               holes 122 while another pin 24 having a transverse screw hole 241 is mounted in the
               holes 222. Then, two ends of the screw rod 31 of the adjusting means 30 are respectively
               threadedly engaged with the transverse screw holes 251 and 241. Thereafter, the holes
               221 of the movable jaw 20 are aligned with the hole 1311 of the recessed section 13,
               and the pin 23 is inserted into the holes 221 and 1311, thereby allowing pivotal movement
               of the movable jaw 20 relative to the fixed jaw 14. It is appreciated that the recessed
               section 13 is received in the space 22 of the movable jaw 20, and the wall members
               27 are respectively located on both sides of the recessed section 13. As shown in
               Fig. 3, the first end 41 of the elastic means 40 is extended into one of the longitudinal
               grooves 312 of the wheel 31 such that the movable jaw 20 is retained in a certain
               angular relationship with the fixed jaw 14 unless a relatively large force is applied
               to rotate the wheel 31 to overcome the force of the elastic means 40 and to urge the
               first end 41 of the elastic means 40 to engage with another longitudinal groove 312.
               It is appreciated that when the movable jaw 20 is adjusted to completely clamp a fastener,
               e.g., a bolt, the wheel 31 may be rotated in a reverse direction such that the first
               end 41 of the elastic means 40 passes through three of the longitudinal ribs 311 at
               which position the movable jaw 20 together with the fixed jaw 14 may securely, adequately
               clamp the bolt in position, i.e., neither too tight nor too loose.
 
            [0016] Fig. 4 illustrates an alternate embodiment of the invention, in which the elastic
               means 40 is replaced by a rod 50 having a first end received in a compartment 15'
               defined in the elongated member 10 and a second end received in one of the longitudinal
               grooves 312, and an elastic member 60 is mounted in the compartment 15' to bias the
               rod 50 upwardly to engage with one of the longitudinal grooves 312.
 
            [0017] Referring to Fig. 5, the wheel 31 may be rotated so as to urge the movable jaw 20
               to pivot relative to the pin 23, thereby changing a distance between the clamping
               section 21 of the movable jaw 20 and the clamping section 141 of the fixed jaw 14.
               Thus, the adjustable wrench in accordance with the present invention may be used to
               clamp fasteners of various sizes, as shown in Fig. 10.
 
            [0018] In operation, referring to Fig. 6, the user may rotate the elongated member 10 in
               a direction (e.g., clockwise) through an angle to tighten or loosen the bolt which
               has been securely clamped between the fixed jaw 14 and the movable jaw 20. Then, if
               the elongated member 10 is stopped by an obstacle, the user may rotate the elongated
               member 10 in a reverse direction (e.g., counterclockwise, see Fig. 7) without the
               need of disengaging the wrench from the bolt, in which the clamping section 141 leaves
               corner "4" and moves toward corner "3", while the clamping section 21 leaves corner
               "1" and moves toward corner "0" to a position shown in Fig. 8, where the user may
               again operate the elongated member 10 in the clockwise direction, as shown in Fig.
               9. It is appreciated that a gap 70 (Fig. 3) is defined between the bolt and the fixed
               jaw 20 which allows convenient reverse rotational movement of the wrench without the
               need of disengaging the wrench from the bolt. In this embodiment, the wrench is rotated
               in the reverse direction through 60 degrees. Nevertheless, further reverse rotational
               movement (e.g., 120 degrees or even more) can be done according to the need.
 
            [0019] According to the above description, it is appreciated that the wrench of the present
               invention can be quickly, easily adjusted to securely clamp the fastener by means
               of rotating the wheel 30, and the structure is simple and the assembly is simple and
               thus is inexpensive in cost. In addition, the elastic means 40, 50 may securely retain
               the movable jaw 20 in position. Furthermore, the reverse rotation of the wheel 30
               which makes the first end 41 of the elastic means 40 to pass through three of the
               longitudinal ribs 311 which allows the wrench to reliably clamp the fastener between
               the fixed jaw 14 and the movable jaw 20, which can be deemed as micro-adjustment of
               the wrench. Moreover, the head portion, i.e., the fixed jaw 14/movable jaw 20 is relatively
               small and thus can be used in a relatively small space.
 
            [0020] Although the invention has been explained in relation to its preferred embodiment,
               it is to be understood that many other possible modifications and variations can be
               made without departing from the spirit and scope of the invention as hereinafter claimed.
 
          
         
            
            1. An adjustable wrench, comprising an elongated member (10) including a first handle
               end and a second end, the second end including a fixed jaw (14) and an engaging section
               (12) formed thereon, a movable jaw (20) having a clamping section (21) formed on a
               first end thereof and a second end pivotally connected to the engaging section of
               the elongated member, and an adjusting means (30) mounted between the second end of
               the elongated member and the movable jaw to urge the movable jaw to pivot relative
               to the fixed jaw, characterized in that:
               
               
the adjustable wrench further includes an elastic means (40; 50, 60) having a first
                  end attached to the adjusting means to frictionally retain the adjusting means in
                  position and a second end securely received in one of the elongated member and the
                  movable jaw.
  
            2. The adjustable wrench according to claim 1, wherein the adjusting means (30) includes
               a screw rod (32) having a first end and a second end, the screw rod includes a wheel
               (31) formed on a mediate section thereof, the movable jaw includes a first pin (24)
               mounted therein, the first pin has a first transverse screw hole (241) through which
               the first end of the screw rod extends, and the engaging section includes a second
               pin (25) mounted therein, the second pin includes a second transverse screw hole (251)
               through which the second end of the screw rod extends.
 
            3. The adjustable wrench according to claim 2, wherein the wheel (31) includes a plurality
               of alternately disposed longitudinal ribs (311) and longitudinal grooves (312), and
               the second end of the elastic means is received in one of the longitudinal grooves.
 
            4. The adjustable wrench according to claim 3, wherein the movable jaw (20) includes
               a compartment (15') defined therein, and the elastic means is a hollow elastic tube
               (40) having a first end (41) received in one of the longitudinal grooves and a second
               end (42) securely received in the compartment.
 
            5. The adjustable wrench according to claim 3, wherein the elongated member (10) includes
               a compartment (15) defined therein, and the elastic means includes a rod (50) having
               a first end and a second end securely received in the compartment, and an elastic
               member (60) is received in the compartment to bias the rod to engage with one of the
               longitudinal groove.
 
            6. The adjustable wrench according to claim 2, wherein the engaging section (12) of the
               elongated member includes a pair of spaced lugs (123) having aligned holes (122) defined
               therein for receiving the second pin (25).
 
            7. The adjustable wrench according to claim 2, wherein the second end of the movable
               jaw (20) includes a pair of spaced wall members (27), the wall members include first
               aligned holes (221) defined in a first section thereof for receiving a third pin (23)
               and second aligned holes (222) defined in a second section thereof for receiving the
               first pin (24), and a recessed section (13) is formed between the fixed jaw (14) and
               the engaging section (12), wherein the recessed section includes a through hole (1311)
               through which the third pin (23) extends.