Abstract:
A bi-directional adjustable spanner with a driving roller comprises a head and a handle. The head includes a movable jaw slidably received within a sliding groove of the head; an adjustable sliding rod; a retaining jaw and a driving roller. The retaining jaw haS a receiving chamber; one side of the receiving chamber having an opening facing the movable jaw. The receiving chamber has a straight receiving groove with a U shape end; the receiving chamber being communicated to the straight receiving groove. The driving roller is received in the receiving chamber of the retaining jaw; and a part of the driving roller protruding out of the opening of the receiving chamber towards the movable jaw. An elastomer is received within the receiving groove. A resisting pin of the elastomer resists against the driving roller. A cover sheet is screwed to the opening of the retaining jaw by a screw.

Description:
FIELD OF THE INVENTION 
   The present invention relates to adjustable spanners, and in particular to a bi-directional adjustable spanner with a driving roller, which can drive a nut or stud to rotate reversily. 
   BACKGROUND OF THE INVENTION 
   In the prior art adjustable spanner, when a nut has rotated through a predetermined angle, the adjustable spanner must leave from the nut and returns to the original position for further driving the nut. Furthermore, the operation is performed repeatedly so as to achieve the object of screwing or releasing the nut. 
   In one prior art, a retaining jaw of the adjustable spanner is a receiving chamber having an opening. A driving roller with two posts at two ends is received within the receiving chamber. Two cover sheets cover the two end surfaces of the retaining jaw. The two posts are resisted by a torsional spring in the retaining jaw. Normally, the driving roller protrudes from the receiving chamber. When the adjustable spanner rotates a nut (stud) and the driving roller suffers from an external force, the driving roller moves along a cambered sliding track formed by the two covers, and moves inwards along the track. Thereby the adjustable spanner rotates reversely without leaving from the nut and then drives the nut (or stud). 
   Above mentioned structure can lock or release a nut or a stud easily and quickly. However, the prior art has the following disadvantages. Firstly, it has the complicated structure. The two surfaces of the retaining jaw must be cut to form a receiving chamber with three open ends. Furthermore, the track is formed by the two covers for confining the two posts. The covers must be formed with sector slots so that when the driving roller moves inwards, the elastomer can be adhered in the sector slot so that the elastomer can effectively resist against the driving roller. Thereby the structure is complicated. 
   It is difficult in the manufacturing process because to form the sector slot is time tedious and needs much works. Thereby the cost is increased for forming the sector slots. 
   The structure of the prior art is weaker. The receiving chamber has three open ends so that the structure is weaker. This will cause that the retaining jaw will be destroyed due to the force from the nut. 
   In another prior art structure, an L shape slot is used to replace the sector slot. However this makes the manufacturing process being tedious and complicated. 
   Furthermore, the when one end of the nut presses the driving roller to move inwards so that the space becomes larger and thus the spanner can rotate around the nut, but the inner side of the movable jaw has a flat surface. No space can receive the apex of the nut as the nut rotates so that the reverse rotation of the nut cannot be performed smoothly. Moreover in some prior arts, lateral sides of the retaining jaw and movable jaw for clamping a nut have respective flat surfaces. This will cause that the nut cannot rotate reversely. 
   Further, the opening of the receiving chamber causes dust to flow into the receiving chamber. As a result, the driving roller cannot move with a sufficient distance so that the function of driving a nut to rotate reversely is lost. 
   SUMMARY OF THE INVENTION 
   Accordingly, the primary object of the present invention is to provide a bi-directional adjustable spanner with a driving roller, where A bi-directional adjustable spanner with a driving roller comprising: a head and a handle; the head including: a movable jaw slidably received within a sliding groove of the head; an adjustable sliding rod for driving the movable jaw; a retaining jaw; one side of the retaining jaw being sealed and another side of the retaining jaw having a receiving chamber; one side of the receiving chamber having an opening facing the movable jaw; at least one guide track being formed in the receiving chamber; a stopper extending from the guide track near an upper side of the opening of the receiving chamber; the receiving chamber having a straight receiving groove with a U shape end; the receiving chamber being communicated to the straight receiving groove; a driving roller received in the receiving chamber of the retaining jaw; and a part of the driving roller protruding out of the opening of the receiving chamber towards the movable jaw; an elastomer received within the receiving groove; a resisting pin of the elastomer resisting against the driving roller for providing the driving roller having a resisting elastic force toward the opening of the receiving chamber; and a cover sheet having a configuration corresponding to the receiving chamber; the cover sheet being screwed to the opening of the retaining jaw by a screw. 
   The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded schematic view about the bi-directional adjustable spanner with a driving roller of the present invention. 
       FIG. 1-1  is a schematic view about another embodiment of the driving roller of the present invention. 
       FIGS. 2 and 3  are operational schematic view about the different views of the driving roller of the present invention. 
       FIG. 4  shows the operation of the present invention, wherein the adjustable spanner rotates clockwise. 
       FIGS. 5-1  to  5 - 3  show the operation of the present invention, wherein the adjustable spanner rotates counterclockwise. 
       FIGS. 6-1  to  6 - 3  is a partial schematic view about the bi-directional adjustable spanner with a driving roller of the present invention. 
       FIG. 7  is a schematic view showing that the adjustable spanner of the present invention clamps a nut. 
       FIG. 8  is a schematic view showing the rotation of the nut by using the bi-directional adjustable spanner with a driving roller of the present invention. 
       FIG. 9  is a schematic view showing a correct clamping about the clamping of a nut by the adjustable spanner of the present invention. 
       FIG. 10  shows the operation of a prior art bi-directional adjustable spanner with a driving roller. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In order that those skilled in the art can further understand the present invention, a description will be described in the following in details. However, these descriptions and the appended drawings are only used to cause those skilled in the art to understand the objects, features, and characteristics of the present invention, but not to be used to confine the scope and spirit of the present invention defined in the appended claims. 
   Referring to  FIG. 1 , the adjustable spanner of the present invention is illustrated. The adjustable spanner  1  has a head  2  and a handle  3 . One end of the head  2  is formed with a retaining jaw  10 . The retaining jaw  10  has a screw rod  30  at a connection of the head  2  and the handle  3  so that the retaining jaw  10  is moved transversally so as to control the gap of a head  2  and the handle  3 . An upper section and a lower section of the inner side of the movable jaw  20  are formed with respective clamping surfaces. The clamping surfaces of the upper and lower sections of the movable jaw  20  are stepped. The connection of the upper and lower sections has a recess  201 . 
   Besides one inner side of the retaining jaw  10  is formed a C shape receiving chamber  11  with a narrow opening and a stepped edge  12 . The receiving chamber  11  serves to receive a driving roller  40  and the stepped edge  12  is covered by a cover sheet  50  so as to form a receiving chamber  11  with only one opening. 
   A lateral wall of an inner side of the receiving chamber  11  is formed with a continuous smooth cambered surface so as to define a guide track  111  and a stopper  112 . The guide track  111  has a receiving groove  13  which is communicated to the receiving chamber  11 . The receiving groove  13  has a straight shape with a U shape bottom for receiving an elastomer  60 . 
   The driving roller  40  is a round block. The lateral side of the driving roller  40  is formed with a smooth surface as shown in  FIG. 2 , or is formed with straight textures as shown in  FIG. 1 , or is formed with a friction portion with intersected lines as shown in  FIG. 1-1  for increasing the friction force connected the driving roller  40  and a nut so as to form the nut to slide in the screwing operation of the spanner. Besides a center of the lateral side of the driving roller  40  is formed with an annular trench  42  for resisting the resisting leg  61  of the elastomer  60 . 
   The cover sheet  50  has a shape corresponding to an appearance of the C shape receiving chamber  11 . A thickness of the cover sheet  50  is identical to the depth between one end surface of the retaining jaw  10  and the stepped edge  12  so that when the cover sheet  50  coves upon the receiving chamber  11 . Other than sealing on open end of the receiving chamber  11 , one outer surface of the cover sheet  50  is flushed with the end surface of the retaining jaw  10 . 
   Besides to make the cover sheet  50  steadily combine to the retaining jaw  10 , in the present invention, the cover sheet  50  has three screw holes  51 ,  52 , and  53 . Two screw holes  51 ,  52  are corresponding to the screw hole  121  of the stepped edge  12 . The middle screw hole  53  of the cover sheet  50  is corresponding to the screw hole  121  of the receiving groove  13 . Screws  100  pass through the screw holes of the cover sheet  50  and then pass through the elastomer  60  in the receiving groove  13  so that the elastomer  60  is steadily secured within the receiving groove  13 . The screw  100  passing through the elastomer  60  can be used as a supporting axial center so as to provide the resisting legs  61  of the elastomer  60  with a larger resisting force to the driving roller  40 . 
   Referring to  FIG. 2 , the adjustable spanner of the present invention has a simple structure so that the assembly efficiency can be improved. In practical assembly, an elastomer  60  is placed in the receiving groove  13 . The resisting leg  61  of the elastomer  60  will protrude in the receiving chamber  11 . Then the driving roller  40  slides into the receiving chamber  11  from the guide track  111 . In the sliding process, the resisting leg  61  falls into the annular trench  42  of the driving roller  40  so that a part of the driving roller  40  protrudes out of the receiving chamber  11 . Then three screws  100  pass through the screw holes  51 ,  52 , and  53  of the cover sheet  50  and then are screwed into the screw hole  121  of the stepped edge  12 . Furthermore, the roll type reversible adjustable spanner of the present invention is assembled. 
   In use of the present invention, referring to  FIG. 4 , when the adjustable spanner  1  clamps a nut A to rotate clockwise, the driving roller  40  will suffer from a resisting force F from the nut A. The resisting force F can be divided into two components F 1  and F 2 . The component F 1  will be cancelled due to the stopper  112  of the retaining jaw  10 . The force component F 2  will generate a torque so that the driving roller  40  rolls toward the driving roller  40 . However it will be cancelled by the stopper  112 . Therefore when the adjustable spanner  1  rotates clockwise, the nut A is locked tightly, and the driving roller  40  is fixed motionlessly. 
   Referring to  FIGS. 5-1 , when the adjustable spanner  1  rotates counterclockwise, the driving roller  40  will suffer from a resisting force F from the nut A. When the resisting force F is divided into components Fb 1  and Fb 2 , the component Fb 1  will cause the driving roller  40  to move toward an inner end of the retaining jaw  10  along the guide track  111 . The component Fb 2  will generate a torque so that the driving roller  40  rolls within the retaining jaw  10  along the guide track  111 . Then, the adjustable spanner  1  of the present invention can rotate reversily without driving the nut A. 
   Referring to  FIGS. 5-2  and  5 - 3 , when the adjustable spanner  1  rotates reversily to a predetermined angle, as shown in  FIGS. 5-3 , the driving roller  40  will return to the original position automatically. Then it can rotate clockwise to tighten the nut A. Thereby under the condition of without releasing the nut A, the nut A can be rotate repeatedly. 
   However in above mention structure to screw the nut repeatedly without falling out, it is known in the prior art, the main feature of the present invention is to provide a simplifying structure to the interior of the retaining jaw. Referring to  FIG. 6 , in the present invention, the driving roller  40  is resisted by the resisting leg  61  of the elastomer  60  in the receiving groove  13 . It can find from  FIG. 6 , the receiving groove  13  receiving the elastomer  60  is different from the prior art L shape groove. The receiving groove  13  of the present invention has a straight shape. Furthermore, the receiving groove  13  is communicated to the receiving chamber  11  so that the receiving groove  13  can be formed by a single process. 
   The simple straight structure of the receiving groove  13  of the present invention causes the assembly process to be easy with a lower cause without using a torsion spring with two resisting elastomers. Thereby it is better than the prior art. 
   Furthermore, the straight structure of the receiving groove  13  has less destroy to the retaining jaw  10 . Thereby it can improve the structure strength of the retaining jaw  10 . 
   Besides the receiving chamber  11  and straight receiving groove  13  do not penetrate through the retaining jaw  10  so that the retaining jaw  10  has a stronger structure. Furthermore, the retaining jaw  10  has a single opening. Only one cover sheet  50  is sufficient in assembly. Thereby the present invention can be assembled quickly. 
   A further feature of the present invention is that an interior of the movable jaw  20  has a stepped surface. A recess  201  is formed between the connection of two stepped surfaces. The effect will be illustrated with referring to  FIGS. 7 and 8 . 
   Referring to  FIG. 7 , when a nut A is placed between two jaws, one surface A 1  of the nut A is adhered to the movable jaw  20 . A lower edge A 2  of the surface is not in contact to the recess  201 . In the driving process, by the recess  201 , the edge A 2  of the nut A can suffer from a larger torque to have a strong structure. 
   The maximum effect of the recess  201  is that when the nut A is driven to rotate counterclockwise, the nut A has a larger moving space so that the operation can be performed easily and smoothly. 
   Referring to  FIGS. 7 and 8 , in the present invention, to prevent the dust from entering into the receiving chamber  11  from the opening due to the inward movement of the driving roller  40  an elastic dust-proof cover  200  is installed at the lower end of the opening of the retaining jaw  10 . The elasticity of the elastic dust-proof cover  200  is slightly smaller than the ejecting force of the driving roller  40 . Normally, when the nut A rotates reversely so that the driving roller  40  moves inwards, the elastic dust-proof cover  200  is not resisted against the driving roller  40 . By the restoring force thereof, the elastic dust-proof cover  200  will cover the opening. Thereby no dust enters into the receiving chamber  11 . 
   Finally, referring to  FIGS. 6-1 , an upper side  101  of the opening of the retaining jaw  10  facing toward the movable jaw  20  has a concave cambered surface  102 . A distance between the upper side  101  and the clamping surface of the movable jaw  20  is S 1 . A surface of the driving roller  40  facing toward the retaining jaw  10  as the driving roller  40  is at the outermost position of the receiving chamber  11  has a distance S 2  with the clamping surface of the movable jaw  20 . The S 1  is slightly smaller than or equal to the S 2 . 
   In use, the spanner of the present invention clamps the nut A which is resisted at the lower apex and the head portion so that it can be driven easily. 
   In the present invention, the distance between the upper side  101  and the clamping surface of the movable jaw  20  is S 1 . The surface of the driving roller  40  facing toward the retaining jaw  10  as the driving roller  40  is at the outermost position of the receiving chamber  11  has a distance S 2  with the clamping surface of the movable jaw  20 . The S 1  is slightly smaller than or equal to the S 2 . Thereby the operation fault can be avoided. 
   The present invention is thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.