Patent Publication Number: US-2015066208-A1

Title: Robotic or mechanical hand with alarm function

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to mechanical hands, and particularly, a mechanical hand with an alarm function. 
     2. Description of Related Art 
     During the rotation of a robot arm or mechanical actuator, people or foreign bodies near to the arm or actuator may be inadvertently injured or damaged, or damage to the arm or actuator may occur. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present disclosure should be better understood with reference to the following drawings. The units in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding portions throughout the several views. 
         FIG. 1  shows an embodiment of a mechanical hand. 
         FIG. 2  is another isometric view of the mechanical hand of  FIG. 1 , viewed from anther view. 
         FIG. 3  shows another embodiment of a mechanical hand, showing a different distribution of infrared distance sensors from that&#39;s of  FIG. 1 . 
         FIG. 4  shows a block diagram of a mechanical hand. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the present disclosure are described, with reference to the accompanying drawings. 
       FIGS. 1-2  show an embodiment of a mechanical hand  100 . The mechanical hand  100  includes a number of infrared distance sensors  10 . The sensors  10  are employed to detect the distance between the mechanical hand  100  and people or foreign bodies. When the distanced sensed by any of the sensors  10  is less than or equal to a preset value, the mechanical hand  100  raises an alarm and stops moving. In this embodiment, the preset value is 50 mm. The preset value can be changed according to need. 
     In this embodiment, the mechanical hand  100  includes a main body  11 . The main body  11  includes a rotary arm  20 , a first rotary shaft  30  rotatably connected to the rotary arm  20 , and a second rotary shaft  40  rotatably connected to the first rotary shaft  30 . The rotary arm  20  includes an upper surface  22 , a lower surface  23  opposite to the upper surface  22 , a left sidewall  24 , and a right sidewall  25  opposite to the left sidewall  24 . The distribution of the sensors  10  can be changed according to need. In a first embodiment, the sensors  10  are arranged on the outer surfaces of the rotary arm  20 , the first rotary shaft  30 , and the second rotary shaft  40 , thus the sensors  10  can detect whether or not people or foreign bodies are near to the mechanical hand  100  in any direction. 
     Referring to  FIG. 3 , in a second embodiment, the sensors  10  includes a first, second, third, and fourth sensor arrays. The first sensor array is arranged on the upper surface  22  of the rotary arm  20 , the second sensor array is arranged on the lower surface of the rotary arm  20 , the third sensor array is arranged on the left sidewall  24  of the rotary arm  20 , and the fourth sensor array is arranged on the right sidewall  25  of the rotary arm  20 . 
     Referring to  FIG. 4 , in this embodiment, the mechanical hand  100  further includes a processing unit  50 , a driving unit  60 , and an alarm unit  70 . The processing unit  50  is connected to the sensors  10 . When the distance sensed by any of the sensors  10  is less than or equal to the preset value, the processing unit  50  activates the alarm unit  70  to raise an alarm for a preset time period, and controls the driving unit  60  to stop moving the main body  11 . After the preset time period has elapsed, the processing unit  50  automatically controls the driving unit  60  to resume the motion of the main body  11 . In an alternative embodiment, after the preset time period has elapsed, the processing unit  50  continues the state of non-motion by the main body  11 . Upon receiving a command input by an operator, the processing unit  50  controls the driving unit  60  to resume the motion of the main body  11 . The alarm unit  70  may be a sound output unit, or may be a number of light emitting diodes arranged on the outer surface of the mechanical hand  100 . 
     In this embodiment, when there are people or foreign bodies near the mechanical hand  100 , the mechanical hand  100  raises an alarm and stops moving. With such configuration, harm to people and harm to the mechanical hand  100  can be both avoided. 
     Although the present disclosure has been specifically described on the basis of the exemplary embodiment thereof, the disclosure is not to be construed as being limited thereto. Various changes or modifications may be made to the embodiment without departing from the scope and spirit of the disclosure.