Flexible plate heat exchangers with variable spacing

Claim 1

IN HEAT EXCHANGER CONSTRUCTION, A PAIR OF SPACED FLEXIBLE HEAT EXCHANGER PLATES FORMING A CHANNEL FOR THE PASSAGE OF HEAT EXCHANGE MEDIUM THEREBETWEEN, AND SEPARATE SPACER MEANS MOUNTED IN SAID CHANNEL FOR LIMITING THE FLEXING OF SAID PLATES TOWARD EACH OTHER, SAID SPACER MEANS HAVING A PORTION FOR LIMITING THE FLEXING OF A PORTION OF SAID PLATES BETWEEN IN VARYING DEGREE, SAID PORTION OF SAID SPACER MEANS BEING FORMED AS A DIMPLE PLATE WITH DIMPLES FORMED OUT OF THE MATERIAL THEREOF EXTENDING LATERALLY TO ONE SIDE AND THE OTHER OF THE PLANE OF SAID PLATE, SAID DIMPLE PLATE BEING POSITIONED BETWEEN THE FLEXIBLE PLATES OF A CHANNEL, SAID DIMPLES BEING UNIFORM IN HEIGHT, SAID SPACER MEANS INCLUDING STRIPS OF MATERIAL OF VARIOUS THICKNESSES SECURED IN OPPOSED RELATIONSHIP WITH RESPECT TO SAID ROWS OF SAID DIMPLES, THE SUM OF THE HEIGHTS OF THE RESPECTIVE OPPOSED DIMPLES AND SPACER MEANS BEING LESS THAN THE DISTANCE BETWEEN THE CONFRONTING SURFACES OF THE FLEXIBLE HEAT EXCHANGER PLATES AND THE MAIN, BASE PORTION OF THE DIMPLE PLATES AT THE LOCATION OF SAID DIMPLES AND SPACER MEANS ALIGNED THEREWITH WHEN THE HEAT EXCHANGER PLATES ARE RELAXED.