Power operated tape measure

Abstract

A hand-held measuring device including a case and flexible steel spring-biased measuring tape wound about an annular reel fitted within a circular housing within the case, a single battery-powered motor having an output shaft, a driving wheel fixedly mounted on the output shaft of the motor for directly engaging the surface of the tape and thereby pushing the tape out of the case, a first switch mounted on the case for controlling the motor, a pull rod connected to the drive wheel, and a second switch mounted on the case and connected to the pull rod for disengaging the driving wheel from the tape surface.

I claim:  
     
       1. A power operated tape measure comprising: 
       a case having a battery chamber and a circular chamber;  
       a motor mounted within said case and having an output shaft;  
       a first switch mounted on said case and electrically connected with the battery chamber of said case for controlling said motor;  
       an annular reel fitted within the circular chamber;  
       a spring-biased tape wound within said annular reel;  
       a driving wheel fixedly mounted on the output shaft of said motor for directly engaging the surface of said tape and thereby pushing said tape out of said case;  
       a pull rod connected to said driving wheel; and  
       a second switch mounted on said case and connected to said pull rod for disengaging said driving wheel from said tape surface so as to allow said spring-biased tape to be taken up.  
     
     
       2. The power of operated tape measure according to  claim 1  wherein said battery chamber contains a conventional battery. 
     
     
       3. The power operated tape measure according to  claim 2  wherein the battery is of the rechargeable type. 
     
     
       4. The power operated tape measure according to  claim 1  wherein said driving wheel comprises a pressure roller. 
     
     
       5. A power operated tape measure comprising: 
       a case having a battery chamber and a circular chamber;  
       a motor mounted within said case and having an output shaft;  
       a first switch mounted on said case and electrically connected with the battery chamber of said case for controlling said motor;  
       an annular reel fitted within the circuit chamber;  
       a spring-biased tape wound within said annular reel;  
       a drive belt detachably mounted on the output shaft of said a motor for directly engaging surface of said tape and thereby pushing said tape out of said case;  
       a pull rod connected to said drive belt; and  
       a second switch mounted on said case and connected to said pull rod for disengaging said drive belt from said tape surface so as to allow said spring-biased tape to be taken up.  
     
     
       6. A power operated tape measure comprising: 
       
         a case;  
       
       
         a battery mounted within the case;  
       
       
         a motor having a motor output shaft, the motor being mounted within the case;  
       
       
         a tape assembly comprising a tape and a reel on which the tape is at least partly wound, where the tape assembly is mounted within the case and is spring biased to wind the tape on the reel;  
       
       
         a drive wheel operatively connected to the motor output shaft such that rotation of the motor output shaft causes rotation of the drive wheel, where the drive wheel is mounted within the case for movement between an engaged position in which the drive wheel engages the tape and a disengaged position in which the drive wheel does not engage the tape; and  
       
       
         a switch set mounted on the case and operatively connected to the battery, the motor, and the drive wheel such that the switch set may be placed in at least a first switch configuration in which the switch set connects the motor to the battery and places the drive wheel in the engaged position to unwind the tape from the reel. 
       
     
     
       7. A power operated tape measure as recited in  claim 6 , wherein the switch set may further be placed in a second switch configuration in which the motor is disconnected from the battery and the drive wheel is in the engaged position. 
     
     
       8. A power operated tape measure as recited in  claim 6 , wherein the switch set may further be placed in another switch configuration in which the motor is disconnected from the battery and the drive wheel is in the disengaged position to allow the tape assembly to wind the tape on the reel. 
     
     
       9. A power operated tape measure as recited in  claim 7 , wherein the switch set may further be placed in another switch configuration in which the motor is disconnected from the battery and the drive wheel is in the disengaged position to allow the tape assembly to wind the tape on the reel. 
     
     
       10. A power operated tape measure as recited in  claim 6 , in which the switch set comprises first and second switches, where the first switch is operably connected between the battery and the motor and the second switch is operably connected to the drive wheel. 
     
     
       11. A power operated tape measure as recited in  claim 6 , further comprising a rod operably connected between the switch set and the drive wheel. 
     
     
       12. A power operated tape measure as recited in  claim 10 , further comprising a rod operably connected between the second switch and the drive wheel such that movement of the second switch between first and second positions causes the drive wheel to move between the engaged and disengaged positions. 
     
     
       13. A power operated tape measure as recited in  claim 6 , further comprising a return spring operably connected between the case and the drive wheel to bias the drive wheel towards the engaged position. 
     
     
       14. A method of causing a tape to extend from a case, comprising the steps of: 
       
         mounting a motor having a motor output shaft within the case;  
       
         providing a tape assembly having a tape and a reel on which the tape is at least partly wound, where the wheel is spring - biased to wind the tape on the reel;    
       
         mounting the tape assembly within the case;  
       
       
         mounting a drive wheel within the case for movement between an engaged position in which the drive wheel engages the tape and a disengaged position in which the drive wheel does not engage the tape;  
       
       
         operatively connecting the drive wheel to the motor output shaft such that rotation of the motor output shaft causes rotation of the drive wheel;  
       
       
         moving the drive wheel into the engaged position and operating the motor such that the drive wheel rotates to displace the tape out of the case. 
       
     
     
       15. A method as recited in  claim 14 , further comprising the step of disconnecting the motor from the battery with the drive wheel in the engaged position. 
     
     
       16. A method as recited in  claim 14 , further comprising the steps of disconnecting the motor from the battery when the drive wheel is in the disengaged position to allow the tape assembly to wind the tape on the reel. 
     
     
       17. A method as recited in  claim 15 , further comprising the steps of disconnecting the motor from the battery when the drive wheel is in the disengaged position to allow the tape assembly to wind the tape on the reel. 
     
     
       18. A method as recited in  claim 14 , further comprising the step of providing first and second switches, where the first switch is operably connected between the battery and the motor and the second switch is operably connected to the drive wheel. 
     
     
       19. A method as recited in  claim 14 , in which the step of moving the drive wheel comprises the steps of: 
       
         connecting a rod to the drive wheel; and displacing the rod to move the drive wheel. 
       
     
     
       20. A method as recited in  claim 18 , further comprising the steps of connecting a rod between the second switch and the drive wheel such that movement of the second switch between first and second positions causes the drive wheel to move between the engaged and disengaged positions. 
     
     
       21. A method as recited in  claim 14 , further comprising the step of connecting a return spring between the case and the drive wheel to bias the drive wheel towards the engaged position.