End effectors and systems including a haptic or audible wear indicator

Abstract

End effectors and systems including end effectors configured to provide audible and/or haptic indicia of fatigue failure of springs disposed in the end effectors are described.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
         1 . An end effector comprising:
 a base portion coupleable to a motor;   a spring coupled to the base portion; and   a mass coupled to the spring configured to move relative to the base portion,   wherein the spring is configured to fatigue and fail after a predetermined number of cycles, and wherein the end effector is configured to provide indicia of fatigue failure of the spring.   
     
     
         2 . The end effector of  claim 1 , wherein the spring and the mass are disposed in an interior portion of a chamber, and wherein the mass is configured to provide an audible or haptic indicia of fatigue failure detectable by a user upon fatigue failure of the spring and movement of the base portion. 
     
     
         3 . The end effector of  claim 1 , further comprising a flag coupled to the mass, wherein the flag is visible to a user before fatigue failure by the spring. 
     
     
         4 . The end effector of  claim 3 , wherein the flag is not visible to a user upon fatigue failure by the spring. 
     
     
         5 . The end effector of  claim 1 , further including one or more stops configured to limit an oscillation of the spring. 
     
     
         6 . The end effector of  claim 1 , wherein the spring includes:
 a portion having a cross section of a first width; and   a notch section having a cross section of a second width less than the first width.   
     
     
         7 . The end effector of  claim 1 , wherein the spring includes a spring material selected from the group consisting of aluminum, an aluminum alloy, steel, titanium, a titanium alloy, a polymeric material, zinc alloys, magnesium and combinations thereof. 
     
     
         8 . The end effector of  claim 1 , wherein the spring includes an aluminum alloy. 
     
     
         9 . The end effector of  claim 1 , wherein the spring is a flexural spring. 
     
     
         10 . The end effector of  claim 1 , wherein the spring is a first spring and the mass is a first mass, the end effector further including:
 a second spring coupled to the base portion; and   a second mass coupled to the second spring configured to move relative to the base portion.   
     
     
         11 . A system comprising:
 an appliance including a motor; and   an end effector coupleable to the motor and configured to receive motion of the motor, the end effector comprising:
 a spring coupled to a base portion; and 
 a mass coupled to the spring configured to move relative to the base portion, 
 wherein the spring is configured to fatigue and fail after a predetermined number of cycles, and wherein the end effector is configured to provide indicia of fatigue failure of the spring. 
   
     
     
         12 . The system of  claim 11 , wherein the motor has a resonant motor oscillation frequency. 
     
     
         13 . The system of  claim 12 , wherein the spring has a resonant spring oscillation frequency that is equal to or substantially equal to the resonant motor oscillation frequency. 
     
     
         14 . The system of  claim 13 , further including one or more stops configured to limit an oscillation of the spring. 
     
     
         15 . The system of  claim 11 , wherein the spring has a resonant spring oscillation frequency that is less than the resonant motor oscillation frequency. 
     
     
         16 . The system of  claim 11 , wherein the spring and the mass are disposed in an interior portion chamber, and wherein the mass is configured to provide an audible or haptic indicia of fatigue failure detectable by a user upon fatigue failure of the spring and movement of the base portion. 
     
     
         17 . The system of  claim 11 , further comprising a flag coupled to the mass, wherein the flag is visible to a user before fatigue failure of the spring. 
     
     
         18 . The end effector of  claim 17 , wherein the flag is not visible to a user upon fatigue failure of the spring. 
     
     
         19 . The system of  claim 11 , wherein the mass is part of an electrical circuit including an indicator configured to provide the indicia upon fatigue failure of the spring. 
     
     
         20 . The system of  claim 11 , wherein the spring includes:
 a portion having a cross section of a first width; and   a notch section having a cross section of a second width less than the first width.