Electric bed

Abstract

An electric bed includes a fixation rack, a back supporting rack swingably disposed to the fixation rack, a head supporting rack swingably disposed to the back supporting rack, an actuator for driving the back supporting rack to swing relative to the fixation rack, a slider disposed to the fixation rack in a way that the slider is forward and backward slidable relative to the fixation rack and being provided with a cam portion, a link pivotally connected with the back supporting rack and the slider to allow the slider to move forward and backward along with the swing of the back supporting rack, a push rod disposed to the back supporting rack and being movable forward and backward, and a front extension rod pivotally connected with the push rod and the head supporting rack.

What is claimed is: 
     
         1 . An electric bed comprising:
 a fixation rack having a front end;   a back supporting rack swingably disposed to the front end of the fixation rack and having a first extending portion and a front end;   a head supporting rack swingably disposed to the front end of the back supporting rack;   an actuator having two ends disposed to the fixation rack and the back supporting rack respectively, such that the back supporting rack is driven by the actuator to swing relative to the fixation rack;   a slider disposed to the fixation rack in a way that the slider is forward and backward slidable relative to the fixation rack, the slider being provided with a cam portion;   a link having two ends pivotally connected with the first extending portion of the back supporting rack and the slider respectively, such that the slider is movable forward and backward along with the swing of the back supporting rack;   a push rod disposed to the back supporting rack in a way that the push rod is movable forward and backward, the push rod having a front end and a rear end; and   a front extension rod having two ends pivotally connected with the front end of the push rod and the head supporting rack respectively;   wherein when the back supporting rack is driven to swing upward, the slider moves forward with the cam portion abutting against the rear end of the push rod to force the push rod to move forward relative to the back supporting rack, the front extension rod then moves forward relative to the back supporting rack to result in that the head supporting rack swings upward relative to the back supporting rack.   
     
     
         2 . The electric bed as claimed in  claim 1 , wherein the first extending portion of the back supporting rack is provided with two clamped rollers, between which the push rod is clamped. 
     
     
         3 . The electric bed as claimed in  claim 1 , wherein the back supporting rack has a second extending portion provided with an elongated groove; the push rod is connected with the front extension rod by a pin that is reciprocally slidably inserted through the elongated groove. 
     
     
         4 . The electric bed as claimed in  claim 1 , wherein the back supporting rack has a stopping portion located under the head supporting rack; when the head supporting rack abuts against the stopping portion, the head supporting rack is prohibited from swinging downward relative to the back supporting rack. 
     
     
         5 . The electric bed as claimed in  claim 1 , wherein the fixation rack has a slide slot; the link is pivotally connected with the slider by a pin that is reciprocally slidably inserted through the slide slot. 
     
     
         6 . The electric bed as claimed in  claim 1 , wherein the rear end of the push rod is provided with a roller for abutting against the cam portion of the slider. 
     
     
         7 . The electric bed as claimed in  claim 1 , wherein the head supporting rack has a lower extending portion; one of the two ends of the front extension rod is pivotally connected with the lower extending portion of the head supporting rack. 
     
     
         8 . The electric bed as claimed in  claim 1 , wherein the back supporting rack has a third extending portion; one of the two ends of the actuator is pivotally connected with the third extending portion of the back supporting rack.