Low Pressure Thermochemical Treatment Machine

Abstract

The invention concerns a treatment machine for low pressure carburizing of metal parts comprising at least one carburizing temperature-setting cell ( 2 ), one carbon-enriching cell ( 3 ) and one carbon-diffusing cell ( 4 ), arranged in succession one after the other. The cells ( 2, 3, 4 ) are of standard shape and of length (L 1 , L 2 , L 3 ) adaptable and proportional to the duration of the treatment performed in each cell. Each cell ( 2, 3, 4 ) comprises a treatment zone ( 14 ) located between an input module ( 10 a ) and an output module ( 10 b ), each constituting a cold zone, thermally insulated from the treatment zone ( 14 ) of the corresponding cell ( 2, 3, 4 ). The machine ( 1 ) comprises means for driving forward and transferring parts between the cells, located in the input ( 10 a ) and output ( 10 b ) modules of the cells ( 2, 3, 4 ).

1 - 15 . (canceled)  
   
   
       16 . Machine for thermochemical treatment of metal parts comprising at least one heating cell, one carbon enriching cell for enriching the surfaces of the parts to be treated, one carbon diffusion cell diffusing from the surface to the core of the parts, and at least one hardening cell, arranged in succession one after the other and having a length adapted to the duration of the treatment performed in each cell, the machine also comprising mechanical means for transferring and moving the parts from one cell to the next and insulating means to insulate the cells from one another during the different successive treatment phases, 
 machine wherein the heating cell, the carbon enriching cell and the carbon diffusion cell are of standard shape and each successively comprise an input module, a low pressure treatment zone and an output module, along a longitudinal axis, the output module of a cell being connected to the input module of the adjacent cell and the input module and output module each forming a cold zone thermally insulated from the treatment zone of the corresponding cell, the mechanical means for transferring and moving being situated in the input module and output module of the cells.    
   
   
       17 . Machine according to  claim 16 , wherein at least the input and output module of the heating cell and of the carbon enriching cell and the input module of the carbon diffusion cell are of standard shape.  
   
   
       18 . Machine according to  claim 16 , wherein, a longitudinal axis of each cell being oriented from the input module to the corresponding output module, each input and output module comprises at least one orifice, respectively an input and output orifice, situated on a wall of said module parallel to said axis, and the means for transferring the parts from each output module to the corresponding input module act perpendicularly with respect to said longitudinal axis.  
   
   
       19 . Machine according to  claim 18 , wherein the longitudinal axes of at least two successive cells are parallel, in the same direction and/or in opposite directions.  
   
   
       20 . Machine according to  claim 16 , wherein the treatment zone of each cell is made up of a corresponding number of standard modules of the same length arranged in series, so that the length of the cell is adapted to the duration of the treatment cycle to be performed in said cell.  
   
   
       21 . Machine according to  claim 16 , comprising gas pumping means connected to the carbon enriching cell and organized such as to create a gas flow from the heating cell and the carbon diffusion cell to the carbon enriching cell.  
   
   
       22 . Machine according to  claim 16 , wherein, the carbon enriching cell comprising means for injecting cementing gases in alternation with neutral gases, said means for transferring and moving the parts are actuated to perform transfer of the parts during injection of neutral gases.  
   
   
       23 . Machine according to  claim 16 , wherein said insulating means of each treatment cell are arranged in a cold zone, in the corresponding input module and output module, and that they thermally insulate the treatment zone from said input and output module.  
   
   
       24 . Machine according to  claim 23 , wherein said insulating means are thermally insulated and cooled doors.  
   
   
       25 . Machine according to  claim 16 , wherein the treatment zone of the heating cell, of the carbon enriching cell and of the carbon diffusion cell is made up of standard modules with cold walls.  
   
   
       26 . Machine according to  claim 16 , wherein the temperature in the treatment zone of the carbon diffusion cell is different from the temperature in the treatment zone of the heating cell and of the carbon enriching cell.  
   
   
       27 . Machine according to  claim 16 , wherein, the input module of the heating cell being connected upline to an additional treatment cell, said input module comprises a pressure-tight door.  
   
   
       28 . Machine according to  claim 27 , wherein said additional treatment cell, arranged upline from the heating cell, is a convective preheating cell.  
   
   
       29 . Machine according to  claim 16 , comprising a tempering cell downline from the hardening cell.  
   
   
       30 . Machine according to  claim 16 , comprising means for cleaning the parts upline from the heating cell.