Patent Publication Number: US-2013233132-A1

Title: Combination structure of head part and grip cover of ratchet wrench

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a ratchet wrench. 
     2. Description of the Prior Art 
     Ratchet wrench is one of the most widely-used tools in our daily life for driving bolts or hats. Referring to  FIG. 1 , a longitudinal sectional view of a conventional ratchet wrench is illustrated. The conventional ratchet wrench integrally formed by a hard metal includes a head part  209  and a body part  210  provided with a core material  211 . A light cladding layer  212  made of aluminum is utilized to enclose from the body part  210  to a sidewall edge of the head part  209 . With the integrally-formed structure by the cladding layer  212 , when using the conventional ratchet wrench to drive the bolt or nut by a user, the conventional ratchet wrench generally can sustain an abutting force acted on the head part  209  thereof, capable of effectively preventing the cladding layer located at the head part  209  from deformation and increasing the structural strength. 
     Due to the circumference of the head part  209  of the conventional ratchet wrench being integrally enclosed by the cladding layer, part of the cladding layer located at the distal end of the conventional ratchet wrench shall be formed with a handheld grip portion with a large outer diameter and a large thickness. However, the portion of the conventional ratchet wrench provided with large thickness is often formed with imperfections in the molding process. Further, the large volume portion of the conventional ratchet wrench provided often needs a longer formation time, and the productivity and the yield rate of the ratchet wrench are relatively decreased. Moreover, due to the cladding layer of the conventional ratchet wrench generally made of expensive, light material such as high molecular polymer, aluminum or magnesium alloy, the productivity competitiveness is lowered in the market and thus unsuitable for being applied in the ratchet wrenches. Improvement on these conventional ratchet wrenches is required. 
     BRIEF SUMMARY OF THE INVENTION 
     In view of this, the purpose of the present invention is to provide a combination structure of a head part and a grip cover of a ratchet wrench, particularly to provide a combination structure of a head part and a grip cover of a ratchet wrench with a high combination fitness. 
     In order to attain the purpose above, the present invention provides a combination structure of a head part and a grip cover of a ratchet wrench. The combination structure includes a head part and a grip cover. The head part includes a bottom end having a front side formed with a first stage portion, a rear side formed with a second stage portion, a left side formed with a third stage portion, a right side formed with a fourth stage portion, and a middle portion provided with a grip body. The grip cover includes a top end and a slot formed on the top end and inserted by the grip body of the head part. At two sides of a top end of the grip cover, a first connecting portion, a second connecting portion, a third connecting portion and a fourth connecting portion are provided. The first, second, third and fourth connecting portions of the grip cover are respectively corresponding to the first, second, third and fourth stage portions of the head part. 
     In the combination structure of the head part and the grip cover of the ratchet wrench provided by the present invention, the first stage portion and the second stage portion of the head part are respectively and correspondingly embedded to the first connecting portion and the second connecting portion of the grip cover, so that the head part and the grip cover are correspondingly embedded and combined to each other and the fitness therebetween can be increased. Furthermore, due to the grip cover formed by injection molding in an independent mold and having easily-controlled molding conditions, it is therefore that the present invention has a low manufacturing cost and high productivity competitiveness in the market 
     A detailed description is given in the following embodiments with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein: 
         FIG. 1  is a longitudinal sectional view of a conventional ratchet wrench; 
         FIG. 2  is an exploded perspective view of a first preferred embodiment of the present invention; 
         FIG. 3  is a side view of a head part of the present invention; 
         FIG. 4  is a front view of a head part of the present invention; 
         FIG. 5  is a front view of a grip cover of the present invention; 
         FIG. 6  is an assembled perspective view of the first preferred embodiment of the present invention; 
         FIG. 7  is a front view of the first preferred embodiment of the present invention; and 
         FIG. 8  is a front view of a second preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 2 , an exploded perspective view of a combination structure of a head part and a grip cover of a ratchet wrench of a first preferred embodiment of the present invention is illustrated. The combination structure mainly comprises a head part  10  and a grip cover  20 . 
     Referring to  FIGS. 3 and 4 , a side view and a front view of the head part  10  of the present invention are illustrated. The head part  10  made of a preferred rigid and hard metal is integrally formed and enclosed by a light material selected from one of high molecular polymer, aluminum or magnesium alloy. In this embodiment, the head part  10  is made of aluminum. A ratchet mechanism  11  is disposed at a rear side of the head part  10 . The head part  10  comprises a bottom end which has a front side formed with a first stage portion  12 , a rear side formed with a second stage portion  13 , a left side formed with a third stage portion  14 , a right side formed with a fourth stage portion  15 , and a middle portion integrally extended with a grip body  16 . In this embodiment, the first stage portion  12  and the second stage portion  13  of the head part  10  are respectively formed of concave arc surfaces. 
     Referring to  FIG. 5 , a front view of a grip cover  20  of the present invention is illustrated. The grip cover  20  made of plastic material is integrally formed of a predetermined shape. Moreover, the grip cover  20  can be made of dual plastic materials by injection molding, so that a gripping effect of a dual material can be provided therewith. The grip cover  20  comprises a top end and a slot  21  which is formed on the top end in an axial direction and provided for being inserted by the grip body  16  of the head part  10 . An elastic body  22  formed as an elastic hollow circular ring is jacketed to the top end of the grip cover  20 . The top end of the grip cover  20  has a first connecting portion  23  corresponding to the first stage portion  12  of the head part  10 , a second connecting portion  24  corresponding to the second stage portion  13  of the head part  10 , a third connecting portion  25  corresponding to the third stage portion  14  of the head part  10 , and a fourth connecting portion  26  corresponding to the fourth stage portion  15  of the head part  10 . In this embodiment, the first connecting portion  23  and the second connecting portion  24  of the grip cover  20  corresponding to the first stage portion  12  and the second stage portion  13  of the head part  10  are respectively formed of convex arc surfaces. Accordingly, the first stage portion  12 , the second stage portion  13 , the third stage portion  14  and the fourth stage portion  15  of the head part  10  are respectively correspondingly embedded to the first connecting portion  23 , the second connecting portion  24 , the third connecting portion  25  and the fourth connecting portion  26  of the grip cover  20 , so that the head part  10  and the grip cover  20  are correspondingly embedded and combined to each other and the fitness therebetween can be increased by the elastic body  22 . 
     In order to further understand the structural features, technical means, and expected functions and effects of the present invention, the detailed operational method of the present invention are described below. 
     Referring to  FIGS. 6 and 7 , an assembled perspective view and a front view of the first preferred embodiment of the present invention are illustrated. Firstly, when the grip body  16  of the head part  10  is inserted in the slot  21  of the grip cover  20 , the first stage portion  12 , the second stage portion  13 , the third stage portion  14  and the fourth stage portion  15  of the head part  10  are correspondingly respectively embedded to the first connecting portion  23 , the second connecting portion  24 , the third connecting portion  25  and the fourth connecting portion  26  of the grip cover  20 , so that the head part  10  and the grip cover  20  are correspondingly embedded and combined to each other with increased fitness therebetween. Further, due to the grip cover  20  formed by injection molding in an independent mold, the molding speed and pressure and other conditions of the grip cover  20  can be easily controlled, thus to provide an optimistic yield of the grip cover  20 . Moreover, with sets of independent molds, various types of the grip covers  20  can be formed in the molding process, capable of providing different type of ratchet wrenches to satisfy different clients&#39; requirements and increasing the productivity competitiveness in the market. 
     Referring to  FIG. 8 , a front view of a second preferred embodiment of the present invention is illustrated. The second preferred embodiment differs from the elastic body  22  is not provided between the first preferred embodiment in that the head part  10  and the grip cover  20 , and the head part  10  and the grip cover  20  still can be embedded and combined to each other with a perfect fitness therebetween.