Abstract:
An ergonomically designed router assembly includes a base assembly coupled with a motor casing including a grip assembly which provides an overall narrower profile to the router assembly. The grip assembly may relieves stress on the muscles and allows the operator to more securely grasp the router with one hand thus decreasing fatigue levels as compared to those routers which require both hands of the operator to be engaged for control over the router.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   The present application is a continuation-in-part under 35 U.S.C. §120 of the U.S. application Ser. No. 10/686,300, filed on Oct. 15, 2003 now abandoned, which claims the benefit under 35 U.S.C. §119(e) of the U.S. Provisional Application Ser. No. 60/418,510, filed on Oct. 15, 2002, and claims the benefit under 35 U.S.C. §119(e) of the U.S. Provisional Application Ser. No. 60/467,169, filed on May 1, 2003. Said U.S. Provisional Application Ser. No. 60/418,510 and said U.S. Provisional Application Ser. No. 60/467,169 are herein incorporated by reference in their entireties. 
   The present application herein incorporates U.S. application Ser. No. 10/384,510, filed Mar. 7, 2003, and U.S. application Ser. No. 10/458,167, filed Jun. 10, 2003 by reference in their entireties. 

   FIELD OF THE INVENTION 
   The present invention generally relates to the field of power tools, and particularly to an ergonomically designed power tool, such as a router. 
   BACKGROUND OF THE INVENTION 
   Routers are employed to accomplish a variety of tasks. Used for shaping objects typically composed of wood, plastic, metal, and the like, routers have become a mainstay of the construction work site and home work shops. From handles located on either side of the housing, to attachments which extend away from the housing, to base designs which allow an operator to guide the operation of the router, controlling the router while in operation has been the purview of many design configurations. And in typical workman-like fashion the design of these handles have often been focused on functionality and not taken into account ergonomic considerations. 
   Typically, ergonomic designs have focused on the structure of the handles and/or external attachments to the routers. For instance, differently shaped handles or various attachment angles thought to provide easier functionality. Additionally, typical router configurations may require the user to grasp the motor housing of the router. These motor housings, surround the motor, and typically leave unused space between the interior of the walls of the housing and the windings of the motor. This may result in a large housing of the router, which may be difficult for the user to firmly grasp, thus, limiting the effective control over the router. Further, the demands placed on the hands of the user, in grasping the large motor housing, may increase fatigue levels which may decrease productivity. Unfortunately, attempts to construct more ergonomically configured routers have fallen short of the goal of providing a significantly easier to operate router. 
   Therefore, it would be desirable to provide an ergonomically designed router to reduce fatigue and improve control over the router. 
   SUMMARY OF THE INVENTION 
   Accordingly, the present invention is directed to a router with an ergonomically designed base and motor casing. Ergonomic design features function to relieve stress on the parts of an operator being used to operate a machine. For instance, providing a thinner handle enables the hand to more comfortably grip an object. This in turn relieves stress on the muscles used for gripping which in turn decreases fatigue levels in those muscles and increases overall performance of the muscles. In the present invention, an ergonomically designed motor casing provides an overall narrower profile, reducing the amount of unused space between the interior of the walls of the motor casing and the windings of the motor. Additionally, a base with a hand cradle assembly is provided for engaging the side of the hand of an operator. These features provide support to the hand of the operator which relieves stress on the muscles and allows the operator to firmly grasp the router with one hand thus decreasing fatigue levels as compared to those routers which require both hands of the operator to be engaged for control over the router. 
   The present invention, further enables the hand of the operator to engage with a grip assembly which provides additionally ergonomic functionality. The grip assembly is designed to incorporate materials which engage the hand of the operator with material as opposed to the metal of the motor casing. The material is designed to flexibly engage the hand of the operator and provide absorption of operational stresses. Such flexible engagement may comprise a grip zone which provides a flexible or cushioned gripping region for the hand of the operator. Operational stress absorption may be provided by the choice of materials employed on the grip assembly, for instance a firmer material may provide a firmer grip region but translate stresses, such as vibrations, at a higher rate than a more flexible material. 
   It is an object of the present invention to provide a router which is ergonomically designed to increase operator comfort and control when operating the router. It is a further object of the present invention to reduce muscle fatigue and the concomitant productivity decrease experienced by users of typical routers. 
   It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The numerous advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying figures in which: 
       FIG. 1A  is an illustration of a router assembly including a motor casing, comprising a grip assembly including a first grip zone, coupled with a base assembly in accordance with an exemplary embodiment of the present invention; 
       FIG. 1B  is an illustration of the router assembly comprising the motor casing coupled with the base assembly, including identification of a horizontal main axis and a vertical main axis of the base assembly, wherein the motor casing presents at a zero degree position relative to the base assembly; 
       FIG. 1C  illustrates the router assembly wherein the motor casing presents at a ninety degree angle, from the zero degree position, relative to the base assembly; 
       FIG. 1D  illustrates the router assembly wherein the motor casing presents at a one hundred eighty degree angle, from the zero degree position, relative to the base assembly; 
       FIG. 2A  is an illustration of a router assembly including a motor casing comprising a grip assembly including a first grip zone and a base assembly comprising a grip assembly including a first grip zone in accordance with an exemplary embodiment of the present invention; 
       FIG. 2B  is an illustration of a router assembly including a motor casing comprising a grip assembly including a first grip zone and a base assembly comprising a hand cradle assembly; 
       FIG. 2C  is an illustration of a router assembly comprising a motor casing including a first grip zone disposed with an actuator for controlling operation of the router assembly; 
       FIG. 3  is an illustration of a router assembly including a motor casing comprised of a grip assembly including a first grip zone and a second grip zone; 
       FIG. 4  is a top plan view of the router assembly, shown in  FIG. 3 ; 
       FIG. 5  is an illustration of a router assembly including a motor casing comprising a grip assembly including a first grip zone disposed with a first first grip; and 
       FIG. 6  is an isometric view illustrating a router assembly including a motor casing comprising a grip assembly including a first grip zone disposed with a first grip and second grip zone disposed with a second first grip. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. 
   Referring generally now to  FIGS. 1A through 6 , exemplary embodiments of the present invention are shown. 
   A router assembly  100  including a motor casing  102  coupled with a base assembly  104 , is shown in  FIGS. 1A through 1D . The motor casing  102  is generally configured to surround a motor. The motor casing  102  is disposed with a first grip zone  106  of a grip assembly  105 . The grip assembly, in the current embodiment, includes the first grip zone  106  disposed on the motor casing  102  in a location proximal to a first knob handle  108  coupled with the base assembly  104 . The base assembly  104  is coupled with the first knob handle  108  and a second knob handle  110 . 
   In the preferred embodiment, the grip assembly is integrally defined within the configuration of the motor casing  102 . In alternative embodiments, the grip assembly may be established in a variety of ways as contemplated by those of ordinary skill in the art. The dimensions established by the configuration of the motor casing  102 , including the first grip zone  106  of the grip assembly  105 , may substantially correspond to a grasp size of an average human hand. The grasp size being defined generally as the area circumscribed by a grasp of a thumb and forefingers of the average human hand. It is understood that the motor casing  102 , which at least partially encompasses a motor (i.e., motor windings), including the grip assembly  105  may provide a configuration which may result in the increased ease of operation of the router and reduction of muscle fatigue in an operator of the router. In alternative embodiments, the motor casing  102  may assume a variety of configurations, which enable the motor casing  102  to surround the windings of the motor and provide similar advantages. It is understood that alternate configuration parameters may be employed without departing from the scope and spirit of the present invention. 
   The motor casing  102  encompasses the motor which includes a router bit engagement assembly  112  that couples with a router bit  114 . An actuator  116  is disposed upon the motor casing  102  for selecting the operation of the router assembly  100 . It is contemplated that the motor casing  102  may be removed from the base assembly  104 . This may allow a secondary motor casing to be coupled with the base assembly  104  or a secondary base assembly, such as a plunge base assembly, to be coupled with the motor casing  102 , thereby increasing the functionality of the motor casing  102  and the base assembly  104 . 
   In the preferred embodiment, the first grip zone  106  of the grip assembly  105  provides an operator a flat surface with which to engage the hand of the operator. Thus, the first grip zone  106  establishes a flat side which may make grasping engagement of the router assembly  100  by the hand of the operator more secure and may decrease fatigue in the hand of the operator. It is understood that the first grip zone  106  may establish various ergonomically correct configurations for the grasping of the router  100  by the hand of the operator without departing from the scope and spirit of the present invention. For example, the first grip zone  106  may be configured with contoured grooves for engaging with individual fingers of the hand of the operator. Alternatively, the first grip zone  106  may be configured with alternating flat regions and rounded regions. 
   In the present embodiment, the first grip zone  106  is disposed on the motor casing  102  proximal to the first knob handle  108 . This location is exemplary for an operator who is right-hand dominant, allowing the operator to engage the dominant hand with the flat surface securing the router assembly  100  in the grasp of the operator. It is understood that the location of the first grip zone  106  may be adjusted to accommodate an operator with a left-hand dominance. In such an instance, the first grip zone  106  may be located proximally to the second knob handle  110 . 
   The position of the first grip zone  106  is changed through use of an adjustment assembly which enables the position of the motor casing  102 , and thusly the first grip zone  106 , to be adjusted in various positions relative to the base assembly  104 . As shown in  FIG. 1B  a main horizontal axis ‘A’ and a main vertical axis ‘B’ may be established for identifying the position of the motor casing  102  relative to the base assembly  104 . For instance, the motor casing  102  and the first grip zone  106  may be located approximately between the first and second knob handles. The various presentation positions of the motor casing  102  and the first grip zone  106  is enabled through the operational coupling of the adjustment assembly with the motor casing  102  and the base assembly  104 . Thus, the motor casing  102  is able to present at various angles relative to a horizontal main axis ‘A’ and the vertical main axis ‘B’. This adjustment capability may promote use of the router assembly  100  when the motor casing  102  is positioned below the operator&#39;s elbow. 
   The adjustment assembly, in preferred embodiments, may comprise a variety of systems allowing for releasing, adjusting, and securing the position of the motor casing  102  relative to the base assembly  104 . For example, a pin alignment system may employ one or more pins which may be removably coupled with one or more grooves disposed within the base assembly  104 . The pins may removably engage with the motor casing  102 , through a boss assembly, and the like, and into the one or more grooves. This type of assembly allows for pre-set angular adjustments to be made. 
   Other assemblies may allow for a user of the present invention to establish a plurality of discrete positions through angular adjustment of the motor casing  102  relative to the base assembly  104 . For example, a compression lock assembly comprising a sleeve defining an open and closed position, disposed within the base assembly  104  and at least partially surrounding the motor casing  102 , may be engaged by a fastener which allows the operator to secure the sleeve in either the open or closed position. When in the open position the operator may rotate the motor casing  102  relative to the base assembly  104  without being limited by pre-set angular adjustment sites. Once the operator has established the desired position of the motor casing  102  relative to the base assembly  104 , the operator may engage the fastener, thereby establishing the sleeve in the closed position. In the closed position the sleeve secures the position of the motor casing  102 . 
   In a still further alternative, the fastening assembly may include a latch assembly which may be released to allow the position of the motor casing  102  to be adjusted relative to the base assembly  104 . Once the new position of the motor casing  102  is established the latch assembly may be engaged to secure the new position and prevent further movement of the motor casing  102  during operation of the router assembly  100 . It is understood that a variety of fastening assemblies may be employed, such as a strap lock assembly, and the like. Alternatively, the fastening assembly may employ fasteners, such as bolts, screws, clips, and the like, which may secure the position of the motor casing  102  relative to the base assembly  104 . It is understood that alternate configurations of the adjustment assembly as contemplated by those of ordinary skill in the art may be employed without departing from the scope and spirit of the present invention. 
   As shown in  FIG. 1B , the motor casing  102  is at a zero degree position, relative to the horizontal main axis ‘A’ of the base assembly  104 , when the first grip zone  106  is located proximal to the first knob handle  108 . The motor casing  102  may be rotated, relative to the base assembly  104 , thereby presenting the first grip zone  106  at various angles relative to the horizontal main axis ‘A’ of the base assembly  104 . In preferred embodiments, the motor casing  102  may be enabled to rotate on the horizontal axis ‘A’ from zero to three hundred sixty degrees or to a discrete position within this range, relative to the base assembly  104 . As shown in  FIG. 1C , the motor casing  102  may rotate so as to position the first grip zone  106  approximately ninety degrees from the initial horizontal zero degree position of  FIG. 1B . In the exemplary embodiment of  FIG. 1D , the motor casing  102  is rotated approximately one hundred eighty degrees on the horizontal axis ‘A’ from the zero degree position of  FIG. 1B . In this embodiment the first grip zone  106  is proximal to the second knob handle  110 , which may enable the use of the router assembly by an operator who is left hand dominant. 
   It is further contemplated that the adjustment assembly may promote the presentation of the motor casing  102  at various angles relative to the vertical main axis ‘B’ of the base assembly  104 , as shown in  FIG. 1B . Preferably, the range of angular adjustment of the motor casing  102  relative to the vertical main axis ‘B’ of the base assembly  104  is between zero to thirty degrees or zero to forty five degrees. Thus, the motor casing  102  may enhance the operator&#39;s ability to utilize the router assembly when the router assembly is positioned below the operator&#39;s elbow. In operation, when the motor casing  102  is presented at an angle relative to the vertical axis ‘B’ of the base assembly  104 , the grip assembly may be located in various positions. For example, the grip assembly may be located on the underside of the motor casing  102  providing the first grip zone  106  in the area engaged by the fingers of the operator when gripping the angled motor casing  102 . 
   Referring now to  FIG. 2A , a router assembly  200  including a motor casing  202 , disposed with a motor casing grip assembly comprising a first motor casing grip zone  204 , is coupled with a base assembly  206  disposed with a base grip assembly comprising a base first grip zone  208 , is shown. In the current embodiment, the first motor casing grip zone  204  and the base first grip zone  208  establish a generally flat gripping area for the hand of the operator. Similar to the grip zone for the router assembly  100 , these two grip zones may be variously configured to provide increased grip-ability and comfort. In the exemplary embodiment, the base first grip zone  208  is located directly in line with the first motor casing grip zone  204  disposed on the motor casing  202 . This alignment of the motor casing first grip zone  204  with the base first grip zone  208  provides an increased flat surface area with which the operator may grasp the router. This may enhance the operator&#39;s grasp of the router, control over the router, and may reduce muscle fatigue due to gripping the router assembly  200 . It is understood that the router assembly  200  may include similar angular adjustment capabilities as described above with respect to  FIGS. 1A through 1D . Therefore, the positioning of the motor casing first grip zone  204  may vary relative to the position of the base first grip zone  208 . 
   It is contemplated that the base grip assembly include a base second grip zone. The base second grip zone may be aligned with a second motor casing grip zone of the motor casing grip assembly, providing an overall narrower profile to the router assembly  200 . It is further contemplated that the motor casing grip assembly and the base grip assembly may include first and second grips coupled with the first and second grip zones disposed upon the motor casing and the base assembly. The grips may provide vibration dampening and may reduce the heat transfer from the router assembly to the hand of an operator. 
   The router assembly  200  further includes a first knob handle  210  and a second knob handle  212  coupled with the base assembly  206 . A router bit engagement assembly  214  is coupled with a router bit  216 , the router bit engagement assembly  214  is also coupled with a motor which is disposed within the motor casing  202 . An actuator  218  is disposed on the motor casing  202  for controlling the operation of the router assembly  200 . It is contemplated that the base assembly  206  disposed with the base first grip zone  208  and the motor casing  202  disposed with the first motor casing grip zone  204  may present at an angle relative to a main axis of the router bit engagement assembly  214  and the router bit  216 . Providing an angled motor casing  202  and base assembly  206  may allow the operator to utilize the router with the router positioned below the operator&#39;s elbow. 
   In the embodiment shown in  FIG. 2B , a router assembly  250  includes a hand cradle assembly comprising a cradle  256 . In the preferred embodiment, the cradle  256  is enabled as a ledge. It is understood that the raised portion, established by the cradle  256 , may be enabled in variety of configurations without departing from the scope and spirit of the present invention. Further, the ledge  256  may be ergonomically configured to engage fully and in the most comfortable manner with the hand of the operator. It is contemplated that the ledge assembly may include an actuator for selecting the operation of the router assembly  250 . In the exemplary embodiment, the ledge  256  is disposed on a base assembly  254  and is located directly in line with a first motor casing flat side  258  disposed on a motor casing  252 . The ledge  256  may be engaged by the hand of the operator, allowing the hand to rest against the ledge  256  which may reduce muscle fatigue. In the preferred embodiment, the ledge  256  is aligned with the first grip zone  258 . Alternatively, the ledge  256  may be in various locations relative to the first grip zone  258 , as enabled by the angular adjustment capabilities of the router assembly  250  which are similar to those shown and described in  FIGS. 1A through 1C  for router assembly  100 . 
   As shown in  FIG. 2C , a motor casing  272 , coupled with a base assembly  274 , comprises a first grip zone  276  including a first actuator  278  for controlling operation of a router assembly  270 . The actuator  278  may be a variety of configurations, such as a two position “on/off” switch, a toggle switch, a button assembly, and the like. It is understood that the positioning of the actuator  278  may increase the ease of controlling the operation of the router assembly  270 . Further, the actuator  278  may be positioned at a bottom or top end of the first grip zone  276  in order to promote efficient control of the motor during operation of the router assembly  270 . Each actuator assembly may be operationally coupled with the motor to control the operation of the motor. 
   Referring now to  FIGS. 3 and 4 , a router assembly  300  is shown. The router assembly  300  includes a motor casing  302  disposed with a grip assembly comprising a first grip zone  304  and a second grip zone  306 . The motor casing  302  is coupled with a base assembly  308  which includes a first knob handle  310  and a second knob handle  312 . An actuator  314  is disposed on the motor casing  302  for controlling the operation of the router assembly  300 . The first and second grip zone  304  and  306  narrow the profile of the router assembly  300 . This narrower profile may enable an operator to grasp the router assembly  300  more securely, maintaining increased control during operation. Additionally, a narrower profile may further increase the gripping comfort experienced by the operator of the router assembly  300 , thereby reducing muscle fatigue in the hand of the operator. For example,  FIG. 4  shows the router assembly  300  being engaged by a hand of an operator. The engagement points of the hand with the router assembly  300  are the first and second grip zone  304  and  306  which allow the operator to establish a secure grasp. In the current embodiment, the thumb engages with the first grip zone  304  and the forefingers engage against the second grip zone  306 . As shown, the palm of the hand may be extended away from contact with the motor casing or in the alternative the palm may be engaged against the motor casing. 
   A router bit engagement assembly  316  couples to a motor disposed within the motor casing  302 . A router bit  318  couples with the router bit engagement assembly  316 . Similar to the angular adjustment capabilities shown and described for the router assembly  100 , in  FIGS. 1A through 1D , it is contemplated that the motor casing  302  may present at an angle relative to a horizontal and vertical main axis of the base assembly  308 . Further, the motor casing  302  may be removed from the base assembly  308  enabling the base assembly  308  to be engaged by a secondary motor casing or the motor casing  302  to be engaged by a secondary base assembly. 
     FIG. 5  shows a router assembly  500  including a first grip  502  disposed on a motor casing  504 . In the exemplary embodiment, the first grip  502  is disposed upon a first grip zone  506  of a grip assembly of the router assembly  500 . The first grip  502  may allow for a more comfortable and secure grasp of the router assembly  500  by an operator. The first grip  502  may be composed of polymeric material, elastomeric material, and the like. In a preferred embodiment, for example, the first grip  502  may be composed of SANOPRENE™, a registered trademark of Roush Industries. The addition of the first grip  502 , upon the first grip zone  506 , may provide vibration dampening and/or vibration attenuation during operation of the router assembly  500  and may reduce heat transfer from the router assembly  500 . It is further contemplated that the first grip  502  may comprise a contoured and/or textured design to enable a firmer grasp by the operator. For example, the first grip  502  may include raised patches, raised lines, relief points, and the like. It is understood that the contouring of the first grip  502  may be varied as contemplated by one of ordinary skill in the art without departing from the scope and spirit of the present invention. 
   It is understood that the location of the first grip zone  506  and thus the first grip  502  may be varied. In the exemplary embodiment, the first grip zone  506  including the first grip  502  is disposed proximal to a first knob handle  510 . This is preferable for a right hand dominant operator of the router assembly  500 . Alternatively, the first grip zone  506  and the first grip  502  may be disposed proximal to a second knob handle  512  which provides increased grasping ability and control over the router assembly  500  to a left hand dominant operator. The position of the first grip  502  may be adjusted through use of an adjustment assembly similar to the adjustment assembly described above in reference to  FIGS. 1 through 4 . 
   The router assembly  500  further includes a base assembly  508  coupled with the motor casing  504 . The base assembly  508  includes the first knob handle  510  and the second knob handle  512 . A router bit engagement assembly  514  is coupled with a router bit  516 , the router bit engagement assembly  514  being coupled with a motor disposed within the motor casing  504 . An actuator  518 , for selection of the operation of the router assembly  500 , is disposed upon the motor casing  504 . As described above, in  FIG. 2C , the actuator may be disposed in various locations and comprise a variety of configurations as contemplated by those of ordinary skill in the art. 
   In the preferred embodiment, the first grip  502  is disposed integrally with the configuration of the motor casing  504 . For example, the first grip zone  506  establishes a recess from the plane of the motor casing  504  and the first grip  502 , coupled with the first grip zone  506 , may fill the recess and re-establish the planar surface. It is contemplated that the first grip  502  may be coupled to the first grip zone  506  of the motor casing  504  using various fastening assemblies. For example, the first grip  502  may be adhered to the first grip zone  506  through a standard manufacture process. The adhering may be accomplished through the use of glue, epoxy, or other substances which provide a similar effect. Alternatively, the first grip  502  may be affixed to the first grip zone  506  of the motor casing  504  through the use of fasteners. Fasteners may include screws, bolts, and the like. Additionally, the first grip  502  may couple with the first grip zone  506  of the motor casing  504  through the use of a magnetic system. The magnetic system may comprise a magnetic strip being placed upon the first grip  502  which is attracted to the metal of the motor casing. Other fastening assemblies may be employed as contemplated by those of ordinary skill in the art. 
   It is contemplated that the first grip  502  may be removed from the first grip zone  506 . Upon removal the first grip  502  may be stored to protect the material composing the first grip  502  and increase its usable life. The enablement of removal may be accomplished through the use of a variety of design implementations. For example, the first grip  502  may be disposed with a loop and hook system. In such an instance, a receiving loop patch may be affixed in position on the first grip zone  506  of the motor casing  504  and be enabled to couple with the first grip  502  which may include a hook patch. Alternatively, when the first grip  502  is secured to the first grip zone  506  through the use of fasteners, as described above, the fasteners may be removed. 
   Referring now to  FIG. 6 , a router assembly  600  including a depth adjustment assembly  602  and a motor casing  604  disposed with a grip assembly comprising a first grip zone  606  and a second grip zone  608 , is shown. It is contemplated that the depth adjustment assembly  602  may be of various configurations and that the assembly shown is merely exemplary and not intended to limit or restrict the use of the present invention. In alternative embodiments the router assembly  600  may include one or three or more grip zones. The first grip zone  606  is further disposed with a first grip  610  and the second grip zone  608  is further disposed with a second grip  612 . The first and second grip  610  and  612  may be similar to those described above in reference to  FIG. 5 . The first grip zone  606  is proximal to the depth adjustment assembly  602 . The motor casing  604  is coupled with a base assembly  614  which is disposed with a first knob handle  616  and a second knob handle  618 . A router bit engagement assembly  620  is coupled with a router bit  622 , the router bit engagement assembly  620  being coupled with a motor disposed within the motor casing  604 . It is understood that the motor casing  604  and/or the base assembly  614  may present at various angles relative to the main vertical and horizontal axis of the base assembly  614 , as described previously in  FIGS. 1 through 5 . 
   The first grip  610  and the second grip  612  may be disposed in various locations upon the motor casing  604 . Further, it is contemplated that the material composing the first and second grips may be disposed within the first and second grip zones locations or may be disposed continuously upon the motor casing  604 , at least partially encompassing the motor casing  604 . In an alternative embodiment, the base assembly  614  may be disposed with a grip assembly comprising a first grip zone and a second grip zone. The base assembly first and second grip zones may be located in alignment with the first grip zone  606  and the second grip zone  608  disposed on the motor casing  604 . However, the first and second grip zones of the base assembly  614  may be disposed in various locations upon the base assembly  614  not necessarily in alignment with the first grip zone  606  and the second grip zone  608  of the motor casing  604 . Further, the base assembly first and second grip zones may be include a base first grip and base second grip, composed of material similar to or varying from the first grip  610  and the second grip  612 , disposed on the first and second grip zone  606  and  608 , respectively. The manner in which the material of the base first grip and base second grip may be disposed on the base assembly is similar to that described previously in  FIG. 5 . 
   It is contemplated that the motor casings and base assemblies shown and described in  FIGS. 1 through 6  are enabled to be retrofitted with existing router assemblies. This is advantageous in providing an operator of the router assembly with interchangeable options. It is believed that the present invention and many of its attendant advantages will be understood by the forgoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.