Vacuum enhancing system or non-evaporable getter

Abstract

Vacuum enhancing system or non-evaporable getter of the type used en solar-receptor vacuum tubes which comprises a series of non-evaporable getter material pads the geometry of which is that of a prism with rounded corners and said pads are drilled through the centre thereof and linked by means of a cable ending in a quick-fit closure that allows the fitting thereof to be automated. This system is placed downstream of the expansion-compensating device in the form of non-radial bellows in the longitudinal direction and in the void defined by the vessel that is the interface part between the absorber tube and the expansion-compensating device. A getter system is placed in a radial arrangement, at each of the two ends of the receptor tube, resulting in a receptor tube of completely symmetrical geometry.

1 . Vacuum enhancing system or non-evaporable getter of the type used in solar-receptor vacuum tubes characterized in that it comprises a series non-evaporable getter material pads ( 1 ) drilled through the centre thereof and linked by means of a cable ( 2 ) ending in a quick-fit closure ( 3 ′,  3 ″,  3 ′″,  3   iv ). 
     
     
         2 . Vacuum enhancing system or non-evaporable getter according to  claim 1  characterized in that the pads ( 1 ) have a prism-shaped geometry with rounded corners. 
     
     
         3 . Vacuum enhancing system or non-evaporable getter according to  claim 1  characterized in that the cable consists of metal. 
     
     
         4 . Vacuum enhancing system or non-evaporable getter according to  claim 3  characterized in that the cable consists of steel. 
     
     
         5 . Vacuum enhancing system or non-evaporable getter according to  claim 1  characterized in that the closure ( 3 ′) comprises two links at the ends of the cable wherein the non-evaporable getter pads are placed so that once these are placed, by placing a pin or rivet between the links, the closed-loop is obtained. 
     
     
         6 . Vacuum enhancing system or non-evaporable getter according to  claim 1  characterized in that the closure ( 3 ″) comprises a clip-type system where when pressing on a female piece with a male piece, the established tolerances allow to guarantee the permanent closure of the loop of the cable where the pads are inserted. 
     
     
         7 . Vacuum enhancing system or non-evaporable getter according to  claim 1  characterized in that the closure ( 3 ′″) comprises two identical pieces which have at their juncture a negative or female where both ends of the cable that defines the loop are housed. The guarantee of the closure is in the rivet that presses and exerts the compressive stress. The pieces do not make contact on their flat sides so that the efforts are made on the ends of the cable and prevent their slip and release. 
     
     
         8 . Vacuum enhancing system or non-evaporable getter according to  claim 1  characterized in that the closure ( 3   iv ) comprises two parts welded to the ends of the cables and that are introduced into each other as a lock, so that its geometry generates a device that prevents accidental opening unless it is properly handled. 
     
     
         9 . Vacuum enhancing system or non-evaporable getter according to  claim 1  characterized in that it is placed downstream of the expansion-compensating device in the form of bellows ( 6 ) in axial direction and in the void defined by the vessel ( 7 ), that is the interface part between the absorber tube ( 4 ) and the expansion-compensating device ( 6 ). 
     
     
         10 . Vacuum enhancing system or non-evaporable getter according to  claim 9  characterized in that a getter system is placed according to a radial distribution in each of the two ends of the receptor tube, resulting in a receptor tube of completely symmetrical geometry. 
     
     
         11 . Vacuum enhancing system or non-evaporable getter according to  claim 10  characterized in that the system could be locked with a series of attachment damps that fix the system to the rest of elements of the absorber tube preventing possible displacements.