Abstract:
A power tool with a gel gripping member has a base with a desired configuration. The base has a desired structural rigidity such that when force is exerted on the base, the base substantially prohibits deflection. A flexible layer covers the base. The flexible layer has a mating configuration slightly larger than the base to form a pocket. A gel material is positioned into the pocket to provide resilient characteristics. A mechanism on the base enables the gel gripping member to be secured with the housing of the power tool.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of U.S. Provisional Application No. 60/685,743, filed on May 27, 2005 entitled “Power Tool with Gel Grip Including an Integral Backing”. The disclosures of the above applications are incorporated herein by reference. 

   FIELD OF THE INVENTION 
   The present disclosure relates to power tools and, more particularly, to power tools that include a handle with a gel grip to provide vibration dampening during operation. 
   When utilizing hand tools, depending upon the use, vibration is created during use of the tool. The vibration, which is created during use, is fed back directly to the user. Thus, the user&#39;s hands, wrists, elbow, etc., absorbs the vibrational shock during use. Accordingly, it would be desirable to provide a hand tool which, during use, reduced vibration. 
   U.S. Patent Application No. 2004/0078936, assigned to the same assignee as the present disclosure, provides a gel grip to dampen vibration. In this disclosure, the handle includes a blister pack which includes the vibration dampening gel. The gel is vacuum formed or heat sealed in a bladder. Thus, the bladder ordinarily necessitates mounting onto a substantially flat planar surface, and must be accommodated as such. While the application works satisfactorily for its intended purpose, designers are always striving to improve the art. 
   The present disclosure provides the art with an improved gel grip for hand and power tools. The present disclosure provides the art with a low cost gel grip which has the ability to form to a curved surface of the tool. The present disclosure provides a backing member with substantial rigidity to provide the gel grip with a desired configuration. The present disclosure provides the art with a backing member that enhances dampening features. Accordingly, gel grips may be positioned on arcuate or angled surfaces and need not be specifically positioned on a planar surface. 
   According to a first aspect of the disclosure, a gripping member comprises a base with a desired configuration. The base has a desired structural rigidity, such that, when a force is exerted on the base, the base substantially prohibits deflection. A flexible layer covers the base. A pocket is formed between the flexible layer and the base. A gel material is inserted into the pocket to provide resilient characteristics to the gripping member. A mechanism is coupled with the base to enable the gripping member to be mounted in a housing. The base has a thin wall portion, preferably inside its periphery, to provide a hinging action. The resiliency enables displacement of the gel material during percussive loads to provide enhanced dampening. The mounting mechanism is a peripheral flange on the base. The base has an overall top hat cross section configuration. The flexible layer has a mating configuration to the base such that, when the flexible layer is overlaid on the base, it provides the pocket. Generally, a metallic layer is coated on the base to provide an aesthetic appearance. The base is generally non-planar along its longitudinal axis and may be arcuate, angled or the like. 
   According to a second aspect of the disclosure, a power tool comprises a housing with an opening. A motor is positioned within the housing. An output is coupled with the motor. The power source, via an activation member, is electrically coupled with the motor. The activation member activates and deactivates the motor which, in turn, drives the output. A gripping member is positioned in the housing opening. The gripping member comprises a base with a desired configuration. The base has a desired structural rigidity such that, when a force is exerted on the base, the base substantially prohibits deflection. A flexible layer covers the base to form a pocket between the flexible layer and the base. A gel material is inserted into the pocket to provide resilient characteristics to the gripping member. A mechanism coupled with the base enables the gripping member to be mounted in the housing opening. The power tool housing has a pair of housing members of the clamshell type to receive the mounting mechanism of the base. Also, a pressure sensor may be positioned in the gel or the base and is coupled with the actuation member to increase or decrease the speed of the output based on the force exerted by the user. The base has a thin wall portion, preferably inside its periphery, to provide a hinging action. The hinging action enables displacement of the gel material during percussive loads to provide enhanced dampening. The mounting mechanism is a peripheral flange extending radially from the base. The base has a top hat cross section configuration. The flexible layer has a mating configuration to the base and is slightly larger to form the pocket. A metallic layer is coated on the base to provide aesthetic characteristics. Also, the base is non-planar along its longitudinal axis so that it may be mounted on various curved, angled and other non-planar surfaces. 
   According to a third aspect of the disclosure, a gel grip is manufactured by comprising vacuum forming a thermoformed polyurethane film to produce an outer layer profile. The profile is cropped to provide a large perimeter around the vacuum formed profile. A base is formed with a metallic finish. The base along with an adhesive film is positioned into the profile of the cover layer. The assembly is placed into a fixture and the cover layer is welded to the plastic base about its periphery. The welding provides a weld around the perimeter; however, two areas, which become an inlet and outlet, are left open to allow access into a pocket formed between the cover layer and the base. The welded gel grip is then placed into a fixture. Gel is injected through the inlet into the pocket. Air escapes through the outlet until the gel fills the pocket. After the gel fills the pocket, the gel injection is halted and the part is removed from the fixture. The part is again placed in the fixture and the inlet and outlet are welded to produce a sealed gel grip member. The gel grip may be cropped and the waste removed from about the periphery and it is readied to be placed into a housing of a power tool. 
   From the following detailed description, taken in conjunction with the accompanying drawings and claims, other objects and advantages of the present invention will become apparent to those skilled in the art. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
       FIG. 1  illustrates a gel grip on a power tool in accordance with the present invention. 
       FIG. 2  is a cross section view of  FIG. 1  along line  2 - 2  thereof. 
       FIG. 3  is an exploded view of the gripping member in accordance with the present invention. 
       FIG. 4  is a plan view of a power tool including a gripping member in accordance with the present invention with a pressure sensor. 
       FIGS. 5-9  are a schematic representation of a method for forming a gel grip. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Turning to the drawings, a power tool is illustrated and designated with the reference numeral  10 . The power tool includes a housing  12  with a pair of clamshell type housing members  14  and  16 . A motor  18 , coupled with an output  20 , is positioned inside of the housing  12 . An activation member  22  is positioned in the housing. The activation member  22  is electrically coupled with a power source  24  and the motor  18 . Here, the power source  24  is shown as a cord which is coupled with a conventional AC outlet. However, a battery, as shown in  FIG. 4 , could act as the power source. Upon energizing or de-energizing the activation member  22 , the motor is activated or deactivated which, in turn, drives the output which, in this case, would drive a reciprocating blade in the illustrated saber or jig saw. The housing  12  includes a handle portion  26  which includes a gel member  30 . 
   The gel member  30 , as best seen in  FIG. 2 , is captured in an aperture  28  in the housing  12 . The aperture  28  is formed between the housing halves  14  and  16 . The housing halves  14  and  16  include recesses  32  and  34  which receive the gel member  30 . The recesses  32  and  34  are elongated channels peripherally positioned about the opening  28  to receive the gel member  30 . 
   The gel member  30 , best seen in  FIG. 3 , includes a base member  40 , a cover layer  42 , a metallic layer  55 , and a gel material  44 . The base member  40 , while being made from a polymeric material, has a sufficient rigidity to provide a desired configuration for the base. The base  40  may have a desired arcuate or non-planar configuration along its longitudinal and/or lateral axes. The base  40 , as well as the gel member is positioned onto the tool as illustrated in  FIGS. 1 and 4 . 
   The base member  40  has an overall hat shape configuration in cross-section. The base has a top wall  46  which is surrounded by an extending circumferential side wall  48 . The side wall  48  extends, substantially perpendicular, from the periphery of the top wall  46 . Also, a flange  50  extends peripherally about and substantially perpendicular to the side wall  48 . The top wall  46  may have a desired configuration, shown here as a rectangle. Thus, the side wall  48 , having four rectangular portions, provides an overall box appearance with the top wall  46 . The top wall  46  includes a groove  52  which is spaced from the periphery of the top wall  46 . The groove  52  forms a localized thin wall section  54  in the top wall  46 . The thin wall  54  provides a hinge point in the top wall  46  which enables the gel material to be displaced under percussive load to enhance the dampening effect of the gel member  30 . 
   The flange  50  extends about the periphery of the base to enable the base to be captured in the recess channels  32  and  34  of the housing members  14  and  16 . Thus, as can be seen in  FIG. 2 , the flange  50  is captured in the recesses  32  and  34  to mount the gel member  30  in the housing  12  of the power tool  10 . 
   Also, the base  40  may include a metallic layer  55  which may be electroplated or otherwise vacuum metallized onto the surface. Ordinarily, a chromium layer is overlaid on the base to provide a metallic appearance through the transparent gel. This provides a silver highly polished surface which provides an aesthetic appearance. 
   The cover layer  42  has a mating configuration to the base  40 . The cover layer  42  includes a top wall  56  an extending circumferential side wall  58  and a flange  60 . The dimensions of the walls  56 ,  58  and flange  60  are slightly larger than the base to form a gel receiving pocket  62  between the base  40  and the cover layer  42 . The gel material  44  is inserted into the pocket  62 . The cover layer  42  has resilient characteristics and has a pleasing feel to the user&#39;s touch. Ordinarily, the transparent cover layer  42  may be a thin polyurethane skin having a desired thickness. The cover layer  42  may be produced as a vacuum formed part with a desired three dimensional configuration which is only limited in curvature available by the thermoforming limitations of the thermoform polyurethane film. 
   The present invention enables the gel grip member  30  to be placed on substantially any surface of the tool. The present invention enables the gel member  30  to be positioned on a curve surfaces of the saber saw, drill handles or the like wherever a user will benefit in degrees of comfort. Also, due to the base and cover layer, a decreasing amount of gel material is required per component. 
   Turning to  FIG. 4 , a power tool is illustrated and designated with the reference numeral  10 ′. The power tool includes a housing  12 ′ with housing halves  14 ′ and  16 ′. The housing includes a motor  18 ′, an output  20 ′, as well as an activation member  22 ′. The power tool  10 ′ includes a power source  24 ′ illustrated as a battery. The activation member  22 ′ is electrically coupled with the battery  24 ′ and motor  18 ′ to activate and deactivate the motor  18 ′ which, in turn, drives the output  20 ′. Also, a gel member  30  is captured between the housing halves  14  and  16  as previously described. The gel member  30 ′ is substantially the same as that described above. As can be seen in  FIG. 4 , the gel member has a more severe curved portion at one of its ends. 
   A pressure sensing device  70  may be positioned within the gel member  30 . The pressure sensing device  70  may be positioned directly onto the base  40  or it may be positioned inside of the gel material  44 . The pressure sensing mechanism  70  is electrically connected to a control switch  72  which controls the current to the motor and, in turn, controls the speed of the output  20 ′. Thus, during operation of the power tool  10 ′, in this example a drill, a user exerts a forward force on the rear of the drill handle. A signal is sent to the speed control circuitry  72  which will translate the user&#39;s forward force on the rear of the drill handle to reduce or increase the drill speed. Accordingly, this will result in more efficient drilling into various types of material. 
   Turning to  FIGS. 5 through 9 , a method of forming the gel member is illustrated. The cover layer  42  is vacuum formed to produce the outer skin profile ( FIG. 5 ). The cover layer  42  may include a textured surface on the cover layer as it is formed from a thermoform polyurethane film. After the cover layer  42  is formed, it is cut or cropped to provide a large diameter about the vacuum profile ( FIG. 6 ). In order to mechanically bond the thermoform polyurethane film to the plastic metallized base, an intermediate or gasket layer of hot metal adhesive film  64  is placed over the rim of the base ( FIG. 7 ). The base  40  with the metallized finish is placed in an upturned position and placed into the thermoform polyurethane film cover layer  42 . This enables the cover layer  42  to be bonded to the base member  40 . After the base  40  is placed into the cover layer  42 , the assembly is placed into a fixture. The thermoformed polyurethane film layer is welded to the plastic carrier around its periphery ( FIG. 8 ). The welding represents a first stage weld. In the first stage weld, two areas  66 ,  68  are left unwelded, which will become the injection  66  and venting points  68  of the gel grip. After the first stage welding is done, the product is placed into a fixture. The fixture is designed to hold the shape of the outer thermoformed form polyurethane film cover layer while the gel  44  is injected through the injection point  66 . While the gel  44  is injected, air escapes through the venting point  68 . The gel is injected until the gel is forced through the venting point. At this time, the process is halted. The part is removed from the fixture and set aside for the next step. The assembly is now placed in a fixture and the remaining non-welded areas are welded. This produces a sealed gel grip component. In the final stage, the gel grip component is cropped and the peripheral material is removed from the part. Accordingly, the part is ready to be added to the housing of a power tool. 
   While the above provides a detailed description of the preferred embodiment, those in the art will appreciate that other modifications, alterations and variations may be made to the present disclosure without deviating from the scope and spirit of the disclosure.