Respirator for the treatment of persons suffering from respiratory insufficiencies

Claim 1

A respirator for persons suffering from respiratory insufficiencies comprising: a respiratory mask, a recipricatory compressor comprising a cylinder having a gas intake orifice and a compressed gas discharge orifice, a piston slidable in said cylinder, spring means acting on said piston to slidably move it in a direction toward said discharge orifice, electromagnet means for moving said piston in a direction away from said discharge orifice when said electromagnetic means is energized, the volume of displacement of said piston in said cylinder being substantially less than the average tidal volume of a patient, means connecting said intake orifice with a gas supply and means connecting said discharge orifice with said respiratory mask, means for energizing said electromagnetic means comprising a supply unit connected to alternating current mains of standard frequency, pulse generating means for supplying to said electro-magnet periodic pulses having a frequency corresponding to said standard frequency when said pulse generating means is energized, and means connecting said pulse generating means with said supply unit comprising clock means for energizing said pulse generating means with alternating current of said standard frequency from said alternating current mains during spaced periods corresponding to insufflation periods and deenergizing said pulse generating means during intervening periods corresponding to expiration periods, whereby said pulse generating means supplies pulses at said standard frequency to said electromagnetic means to produce reciprocation of said piston in said cylinder at said standard frequency to pump gas from said gas supply to said respiratory mask under pressure during said insufflation periods only, said electromagnetic means being deenergized and said piston being inoperative during intervening exhalation periods, control means for modifying said pulses supplied by said pulse generating means to said electromagnetic means by varying the width of said pulses and thereby controlling the output of said compressor, and valve means for venting said respiratory mask to the atmosphere to relieve said pressure during said exhalation periods.