Patent Publication Number: US-2006007149-A1

Title: Ergonomic pointing device

Description:
FIELD OF THE INVENTION  
      The present invention relates to a pointing device (mouse) for control of cursor movements on a display. More particularly, the present invention concerns a pointing device ergonomically designed to minimize repetitive stress injuries.  
     BACKGROUND OF THE INVENTION  
      A pointing device, otherwise known as a mouse, is commonly used to direct the movement of a cursor on a computer display. The pointing device is typically used in order to specify a location on a computer display or to control the operation of applications and program in operating systems utilizing a graphical user interface. Typically, the pointing device is manipulated on a desk top and this movement is translated as movement of a cursor on a computer display. The pointing device will also typically include a selection mechanism, typically a button, which is used to indicate where an action is to be performed or which is used to activate programs and applications.  
      Positioning a cursor on a computer display will typically involve moving a pointing device on a flat surface and having this movement translated by the computer system into an equivalent movement of the cursor on the graphic display. This translation is typically implemented by using a trackball mechanism comprised of a ball and a pair of rollers, each roller corresponds to an axis along a two dimensional plane (x or y). Movement of the pointing device causes a rotational movement in the ball, and this rotational movement is translated by each roller as movement along its respective axis. The cursor is then depicted on the display as performing a corresponding movement.  
      Typically, once a cursor has been positioned at a particular location or upon an icon or an application, a selection mechanism is activated in order to instruct the computer system to perform a function at the location or with respect to the selected icon or application. A typical pointing device will have a selection mechanism comprised of a button coupled to a pressure switch. The button is typically located at the surface of the top portion of the pointing device, and is activated by pressing downward with a finger.  
      Operating a pointing device often requires extensive movement of the wrists and fingers. In addition, common embodiments of pointing devices often require unnatural flexion of wrists and fingers. When done repeatedly, these actions create static muscle loading and physical stress in the wrist and fingers which fatigue the hand of a user. Continual use of known pointing devices can also lead to repetitive-stress injuries such as carpal tunnel syndrome.  
      Consequently, there is a need in the art for a pointing device which will reduce the amount of motion and unnatural flexion of the wrists and fingers.  
     SUMMARY OF THE INVENTION  
      In light of the drawbacks of the prior art, the present invention concerns a pointing device adapted to minimize unnatural flexion and movement of the wrist and fingers. The pointing device is comprised of a body with a top portion and a bottom portion. The top and bottom portions cooperate to define an internal space within the body.  
      In one embodiment, the top portion is a generally rounded surface and is sized to accommodate a user&#39;s palm. A protuberance comprised of a wall portion and a tongue portion extends longitudinally along the top portion. The wall portion is curved to engage confronting sides of adjacent fingers. The tongue portion extends from the protuberance and functions to retain the fingers in an engaged position with respect to the wall portion.  
      In one embodiment, the present invention includes a scroll wheel positioned adjacent to a user&#39;s thumb. The scroll wheel rotates about an axis which is generally perpendicular to the top portion, with the wheel being generally parallel to the bottom portion.  
      In one embodiment, the present invention includes a bottom portion comprised of a generally flat surface and a generally rounded surface. The flat surface is positional in a central region of the bottom portion and is generally oval shaped. The rounded surface peripherally surrounds the flat surface and is comprised of a left section and a right section.  
      In one embodiment, a selection mechanism is coupled to the rounded surface and a cursor positioning mechanism is coupled to the flat surface. The selection mechanism includes separate pressure switches coupled to each of the left and right sections. The cursor positioning mechanism includes a track ball mechanism.  
      The present invention alleviates the need to grip the pointing device by enabling it to be manipulated by simply moving the larger forearm muscles. To activate the selection mechanism, the user rotates the forearm causing the subject pointing device to roll onto the right or left rounded section. This eliminates the need to use independent finger movements to activate the selection mechanism and minimizes wrist movement. Engaging confronting sides of both the index and middle finger the protuberance enables the forearm to guide the direction of the pointing device and minimizes wrist movement. The palm of a hand is able to rest upon the top portion in a relaxed position while the pointing device is being manipulated by the forearms. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS AND FIGURES  
      For purposes of facilitating and understanding the subject matter sought to be protected, there is illustrated in the accompanying drawings an embodiment thereof. From an inspection of the drawings, when considered in connection with the following description, the subject matter sought to be protected, its construction and operation, and many of its advantages should be readily understood and appreciated.  
       FIG. 1  is a perspective view of one embodiment of the present invention.  
       FIG. 2  is a side view of the embodiment of  FIG. 1 .  
       FIG. 3  is an overhead plan view of the embodiment of  FIG. 1 .  
       FIG. 4  is a bottom plan view of the embodiment of  FIG. 1 .  
       FIG. 5  is an overhead view of the embodiment of  FIG. 1  engaged by a user&#39;s hand. 
    
    
     DETAILED DESCRIPTION  
      As shown in  FIGS. 1, 2 , and  3 , the present invention concerns a pointing device  10  adapted to minimize movement and unnatural flexion of the wrist and fingers. The pointing device is comprised of a body  11  with a top portion  12  and a bottom portion  14 . The top  12  and bottom  14  portions cooperate to define an internal space within the body  11  in which components of the pointing device are located.  
      In one embodiment, the top portion  12  is a generally rounded surface and sized to accommodate and support a user&#39;s palm. The top portion  12  may include ergonomically positioned structures such as depressions, ridges, and raised surfaces in order to better accommodate the fingers and palm. The top portion  12  can also have padded materials affixed thereto in order to minimize pressure points on the hand. Padding materials, such as a gel pack or pad, can be provided at top portion  12 . In another embodiment of the invention, a gel pad may be adhesively secured to the top portion  12 .  
      In one embodiment, a protuberance  18  extends longitudinally along the top portion  12 . The protuberance is comprised of a wall portion  20  and a tongue portion  22 . The wall portion  20  is curved in order to comfortably engage confronting sides of adjacent fingers. The tongue portion  22  extends from the wall portion and is adapted to retain adjacent fingers in an engaged position with respect to the wall portion. The edges of the tongue portion  22  may also be curved in order to better retain an engaged finger. Preferably, the protuberance  18  is positioned to engage confronting surfaces of the middle and index fingers.  
      In one embodiment, the present invention includes a scroll wheel  26  extending through the top portion  12 . The scroll wheel utilizes known hardware and software to interface with the scrolling functions of known applications. The scroll wheel  26  is positioned adjacent to a user&#39;s thumb and is adapted to rotate about an axis which is generally perpendicular to the top portion; the scroll wheel  26  is generally parallel to the bottom portion.  
      As shown in  FIGS. 2 and 4 , in one embodiment, the present invention includes a bottom portion  14  comprised of a generally flat/planar surface  30  and a generally rounded surface  32 . A selection mechanism (not shown) is coupled to the rounded surface  32  and a cursor positioning mechanism  36  is coupled to the flat surface  30 . The bottom portion  14  is generally frusto-spheroidal shaped enabling the pointing device  10  to maintain a stable upright position when not being used.  
      As shown in  FIG. 5 , in one embodiment the flat surface  30  is positional in a central region of the bottom portion  14  and is generally oval shaped. The flat surface  30  comprises roughly 50% or more of the surface area of the bottom portion  14 . As such, the flat surface  30  forms a generally stable base, maintaining the present invention in an upright position during and after its use.  
      The cursor positioning mechanism  36  is located in the flat surface  30 . In one embodiment, the cursor positioning mechanism includes a track ball mechanism. Typically, the track ball mechanism includes a ball which extends partially through the flat surface  30  and rollers (not shown) located within the pointing device  10 . The rollers engage the ball and translates the rotation of the ball into movements along a two-dimensional plane (x and y axis). The track ball mechanism and its associated software can be one which is known in the art. It has also been contemplated that other known cursor positioning mechanisms such as magnetic mechanisms and optical mechanisms be implemented.  
      In one embodiment, the bottom portion  14  includes a rounded surface  32  which peripherally surrounds the flat surface  30 . The rounded surface is comprised of a left section  38  and a right section  40 . A spring mechanism (not shown) is coupled to an interior surface of each of the left  38  and right  40  sections. The spring mechanism supports each section and enables each to independently and resiliently travel in a direction generally perpendicular to the flat surface  30 .  
      In one embodiment, each of the left  38  and right  40  sections are coupled to a selection mechanism disposed within the pointing device. The selection mechanism cooperates with hardware and software that is known in the art and which enables the selection mechanism to interface with known graphical user interfaces. Preferably, the selection mechanism includes separate pressure switches coupled to each of the left and right sections. The pressure switches are closed/opened when its respective section travels a sufficient distance. Alternatively, a pressure switch may partially extend from each of the right and left sections.  
      As shown in  FIG. 5 , the present invention enables the palm of a hand to rest upon the top portion in a relaxed position. In one embodiment, the protuberance is positioned to engage confronting sides of both the index and middle finger. As such, there is no need to grip the pointing device, and the pointing device is able to be manipulated by simply moving the larger forearm muscles. Furthermore, the flat surface  30  maintains the pointing device in a generally upright position, alleviating the need for the wrist to balance the pointing device during its use. These features significantly reduces stress and strain on the more delicate hand and wrist muscles.  
      Furthermore, the present invention also includes a selection mechanism which is coupled to the rounded surface located on the bottom portion  14 . To activate the selection mechanism, the user rotates the forearm causing the subject pointing device  10  to roll onto the right or left rounded section. This eliminates the need to use independent finger movements to activate the selection mechanism.  
      As a result of the ergonomic improvements in the subject invention, the operator of the subject pointing device mostly recruits the larger forearm muscles, and minimizes the movements of the weaker and smaller wrist and hand muscles. This enables a user to utilize a pointing device for a longer period of time and alleviates movements which contribute to repetitive stress injuries such as carpal tunnel syndrome.  
      The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. While a particular embodiment has been shown and described, it will be apparent to those skilled in the art that changes and modifications may be made without departing from the broader aspects of applicant&#39;s contribution. The actual scope of the protection sought is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.