Patent Publication Number: US-10780557-B2

Title: Slugging wrench

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is the United States national phase of International Application No. PCT/NL2013/050097 filed Feb. 15, 2013, and claims priority to Netherlands Patent Application No. nl2008298 filed Feb. 15, 2012, the disclosures of which are hereby incorporated in their entirety by reference. 
     The present invention relates to a slugging wrench for exerting slugging force on a fastening member such as a nut during tightening or loosening thereof. 
     Slugging wrenches are per se known devices used to transmit a slugging force to a nut when the nut is too tightly fixed to be able to remove, loosen or tighten it without the slugging force. A slugging wrench is provided for this purpose with a slugging surface, preferably arranged opposite the ring on a handle, which can be struck with a hammer. 
     Although the advantage of using a prior art slugging wrench is apparent, a significant drawback is that many injuries occur during use because the hand holding the wrench on the nut is struck by the hammer. Such injuries cause much personal distress and result in much operational damage. 
     In order to prevent such drawbacks of the prior art in the future the present invention provides a slugging wrench for exerting slugging force on a fastening member such as a nut during tightening or loosening thereof, the slugging wrench comprising:
         an arm,   an impact absorbing element arranged on the arm for absorbing the slugging force,   a receiving member for receiving the fastening member,   wherein the receiving member is provided with an inner surface fitting in force-transmitting manner on an outer surface of the fastening member and preferably having in a view, such as in the in-feed direction, a shape such as a polygon, such as a hexagon, such as a dodecagon,   wherein the inner surface is provided with at least two grooves respectively suitable for receiving a clamping member for the purpose of providing a clamping action in respect of the fastening member.       

     An advantage of such a slugging wrench according to the present invention is that, due to the clamping action in respect of the fastening member, the slugging wrench remains positioned without being held fast by the hand. It hereby becomes possible to avoid injury. Greater concentration can further be focused on striking in correct manner, whereby slugging takes place more carefully and there is better focus on the correct orientation of the slugging force. A further advantage of a device according to at least a preferred embodiment according to the present invention is that, when a clamping member clamps round a fastening member, the fastening member is clamped firmly in the receiving member, which is in turn held fast in the respective groove. 
     According to a first preferred embodiment of the present invention, the slugging wrench comprises at least the one clamping member, preferably per groove, wherein the clamping member is substantially circular, or wherein the clamping member is substantially polygonal so as to substantially match the shape of the inner surface. 
     It is advantageous here for a clamping action to be imparted to the fastening member. The substantially circular variant provides clamping action at the vertices of a fastening member such as a nut. The substantially polygonal variant, or star-shaped variant, can provide clamping action at the vertices of a fastening member such as the nut or, conversely, provide clamping action on the flat parts of a fastening member such as the nut. The clamping member therefore more preferably provides a clamping force here to the vertices of the fastening member which define a circumscribed circle, and/or flat parts of the fastening member. 
     In a further preferred embodiment the clamping member provides a spring force and preferably comprises for this purpose a metal, such as preferably steel, such as more preferably processed steel such as spring steel. Such a robust embodiment provides a strong clamping action or spring force. 
     The inner surface of the ring of the slugging wrench is more preferably dimensioned relative to standard sizes of fastening members in order to provide a certain play between the outer surface of the fastening member and the inner surface of the slugging wrench, wherein the depth of the groove is smaller than a diameter of the material of the clamping member, preferably less than 0.9 times the diameter, more preferably less than 0.8 times the diameter, more preferably less than 0.6 times the diameter. 
     Such an embodiment assists in providing a greater stability of the slugging wrench relative to the fastening member, since it contributes toward reducing the play between the fastening member and the inner surface of the ring of the slugging wrench. A slugging wrench has a relatively large play between the outer surface of the fastening member and the inner surface of the ring of the slugging wrench. The slugging wrench can hereby be arranged easily and can also be arranged when the outer surface of the fastening member is damaged. Such a large play has the drawback that the slugging wrench easily detaches from or falls off the fastening member. A slugging wrench according to the present invention assists in reducing or obviating such a drawback. 
     In a further preferred embodiment a centre-to-centre distance of an outer groove or outer clamping member relative to the height of the inner surface is arranged at 0.10.4 or 0.60.9 of the height of the inner surface relative to the underside or the upper side. Hereby achieved in advantageous manner is that the effective force of the clamping members is great due to the relatively large mutual distance. 
     It is advantageous in the slugging wrench according to the present invention when in a preferred embodiment the clamping member is an open ring or retaining ring. Hereby achieved is that this member can be placed and removed, or replaced, in simple manner. Replacement can be advantageous when the clamping member becomes damaged or the spring force decreases. Such a measure also provides for interchange ability between different types of clamping member. 
     When in an embodiment the clamping member and/or the clamping members define in the slugging wrench a clamping plane which preferably has a substantially cylindrical shape with some height and which more preferably extends over at least 80%, preferably 90% of the periphery of a cylinder, this achieves that a relatively great force for holding the slugging wrench relative to the fastening member is realized relative to the size of the ring of the slugging wrench. 
     In a further preferred embodiment the inner diameter of the clamping member in non-tensioned state is smaller than a circumscribed circle of the fastening member intended for the slugging wrench, is more preferably smaller than an inscribed circle of the inner surface, is more preferably smaller than a circle of the inner surface defined by outward pointing vertices of the star formed by the inner surface. A clamping force is hereby obtained on the fastening member in advantageous manner. Also achieved is that the clamping member can of itself exert a force on the fastening member, after which, due to the presence of the clamping member in the groove, the surfaces of the groove hold the clamping member fast, thereby achieving that the play between the fastening member and the inner surface is of minor importance. No matter how the clamping member or the clamping members with the fastening member arranged therein may be oriented relative to the groove of the slugging wrench, the clamping members are always held fixedly by the groove. 
     In a further preferred embodiment the slugging wrench comprises a stop for positioning the clamping member in a rotational direction which is preferably arranged in at least one of the respective grooves. Particularly in the case of a noncircular clamping member this achieves that the positioning of the clamping member in rotational direction is of a shape similar to the form of the inner surface. The clamping member more preferably has substantially a star shape on the inner side thereof, preferably in the form of a substantially wire-like ring with bends. It hereby becomes possible for the clamping member to clamp over a greater part of the length thereof for the purpose of a better clamping relative to the fastening member. 
     When bulges are arranged on the inner side of the clamping member for engagement thereof on the fastening member, a relatively firm clamping is realized during holding of the fastening member. 
     The clamping member is more preferably embodied as a flat retaining ring. 
     The clamping member more preferably comprises pressing bulges for pressing against the outer wall of the groove. 
     A pressing surface of the groove more preferably comprises bulges for pressing the clamping member against the fastening member. 
     In the slugging wrench according to one or more of the foregoing claims the receiving member comprises in a further preferred embodiment at least one opening for providing a lateral passage for the fastening member. Using such an opening an operation as in the case of an opened wrench is provided in a slugging wrench according to the present invention. This is advantageous for instance in the case the fastening member cannot be reached by means of an annular receiving member, and the lateral insertion provides the solution here-for. 
    
    
     
       Further advantages, features and details of the present invention will be described in greater detail herein-below on the basis of one or more preferred embodiments with reference to the accompanying figures. Similar, though not necessarily identical, components of different preferred embodiments are designated with the same reference numerals. 
         FIG. 1  is a perspective view of a first preferred embodiment according to the present invention. 
         FIG. 2  is a schematic top view of a further preferred embodiment. 
         FIG. 3  shows two further preferred embodiments in cross-section. 
         FIG. 4  shows a cross-sectional detail of the embodiment according to  FIG. 1 . 
         FIG. 5  shows a cross-sectional detail of a further preferred embodiment. 
         FIG. 6  shows a detail of a further preferred embodiment. 
         FIG. 7  shows a perspective, front and side view of a detail of the embodiment according to  FIG. 6 . 
     
    
    
     A first preferred embodiment ( FIG. 1 ) according to the present invention relates to a slugging wrench  1  having an arm  9  and a receiving member  17 . This comprises clamping rings (clamping members)  7 ,  8  arranged in a groove  6  on the inner side of ring  2  of the slugging wrench. Although the ring can be a hexagon, the present ring is a dodecagon. A central part of ring  2  of the slugging wrench is formed by nut engaging surfaces  3 , and situated on the upper side are nut engaging surfaces  5  and on the underside nut engaging surfaces  5 ′. Arranged therebetween are two grooves  12  which can for instance be formed by a milling operation. The dual embodiment of grooves  12  and the clamping rings  7 ,  8  arranged therein provides a relatively high clamping force relative to the nut (not shown). 
       FIG. 2  shows that clamping rings  7 ,  8  are substantially circular with a recess with an opening, whereby they can be bent so far inward that they can be placed in a groove after the groove has been arranged in the ring of the slugging wrench. 
       FIG. 3  shows cross-sections of two variants of ring  7 ,  8 . Ring  7  is manufactured from a substantially wire-like material of for instance spring steel. The rounding of the wire-like material makes it possible for the nut to be pressed through the ring, wherein the ring is forced outward. Ring  8  is a variant in flat steel material. For the purpose of obtaining the same action as ring  7 , it is provided on the inner side with a curvature or chamfering so that the ring is pressed outward during placing of the slugging wrench on a nut. 
       FIG. 4  shows a cross-section of ring  2  of the slugging wrench according to  FIG. 1  along the line IVIV. In this preferred embodiment the depth (D 1 ) of the groove is no deeper than the cross-section of the ring or the thickness of the ring as seen in top view, at least at the locations of the ring wrench where the vertices of the nuts can be placed. This achieves that the ring can provide a clamping action between rear wall  19  of the groove and the nut. 
       FIG. 5  shows a further variant wherein the rear wall  14  of the groove is provided with protrusions or bulges  13  for the purpose of providing a stop for the outer side of the ring  7  there-against. The positioning of these bulges  13  is such that it corresponds substantially to the centre of the surfaces  17  of the nut. A material tension can hereby be realized in the resilient ring  7  between bulges  13  and the vertices of the nut, whereby a strong spring force is realized in an alternative manner between the groove and the nut by means of ring  7 . 
     A preferred embodiment is embodied as open-end wrench, whereby the ring is open on one side with an opening which is substantially slightly larger than one of the side views of the nut. The head of this open-end wrench is shown from the top in a sectional view. As is per se usual in the case of an open-end wrench, it comprises two nut engaging surfaces  21 ,  22  for engaging a nut. 
     As in previous preferred embodiments, grooves  24  are arranged in these engaging surfaces  21 ,  22  for receiving two springs  25 ,  26 , one on each side of the head. The springs extend from a placing recess  28 ,  29  in a respective groove with a variable depth. Realized by means of this variable depth of the groove is that the spring can move outward during placing of the nut in the head, such as between surfaces  21 ,  22 . 
     When the nut is inserted, the springs bring about engagement on either side of two opposite side surfaces of the nut. An end part  31  of the spring optionally engages round the placed nut. Alternatively, the lateral clamping of the springs will suffice. 
     For the purpose of the dual embodiment of the spring on either side, the spring is embodied as if it were a bent staple. The spring has for this purpose two legs  26 ,  26 ′ and an end bridge element  31  for the mutual connection. Realized in advantageous manner by means of such a preferred embodiment is that damage to spring end parts is prevented. 
     The present invention has been described in the foregoing on the basis of several preferred embodiments. Different aspects of different embodiments are deemed described in combination with each other, wherein all combinations which can be deemed by a skilled person in the field as falling within the scope of the invention on the basis of reading of this document are included. These preferred embodiments are not limitative for the scope of protection of this document. The rights sought are defined in the appended claims.