Abstract:
The invention relates to a steam peeling device comprising a vessel provided with a closable opening near one end for introducing and removing products to be processed. The opposite end of the vessel is closed by an end wall. A device for supplying steam to the vessel are furthermore provided. The vessel is rotatable about an at least substantially horizontal axis of rotation, which is positioned between the two ends of the vessel and which extends transversely to the longitudinal axis of the elongated vessel. A perforated jacket surrounding the receiving space all round is disposed within the vessel, spaced from the wall thereof by a short distance. A supply pipe for steam opens into the space present between the wall of the vessel and the jacket.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a steam peeling device comprising a vessel provided with a closable opening near one end for introducing and removing products to be processed, wherein the opposite end of the vessel is closed by an end wall, and means for supplying steam to the vessel, wherein the vessel can be rotatably driven about an at least substantially horizontal axis of rotation, which is positioned between the two ends of the vessel and which extends transversely to the longitudinal axis of the elongated vessel. 
     2. Description of the Prior Art 
     In a steam peeling device as for example known from EU-A-0 146 153, the steam is supplied via a basket formed by grid bars, which is centrally disposed in the vessel, wherein the steam enters the interior of the vessel over a comparatively small area so as to come into contact with the products that surround the basket at least partially. 
     A further steam peeling device known from EU-A-0 078 587 comprises a steam supply channel which extends in a U shape along he inner wall of the vessel, wherein the wall of said channel that faces towards the interior of the vessel is perforated. Also in this known construction the steam enters the interior of the vessel over a comparatively small area. 
     SUMMARY OF THE INVENTION 
     According to the invention a perforated jacket surrounding the receiving space all round is disposed within the vessel, spaced from the wall thereof by a short distance, and a supply pipe for steam opens into the space present between the wall of the vessel and the jacket. 
     The steam that is supplied to the interior of the vessel is thereby distributed over the largest possible area, as a result of which a quicker and better influence of the steam on the products can be obtained than with the conventional construction. 
     Efficiently, a partition plate which is fixed to the inner wall of the vessel is disposed in the vessel, between the end of the vessel comprising the end wall and the substantially horizontal axis of rotation, in the central portion of which partition plate a passage is formed, whilst means for removing condensate are provided, which means communicate with the space between the end wall and the partition plate, wherein the device includes a valve mechanism, which shuts off the passage in the central portion in a first position and which releases said passage in a second position so as to place the space between the end wall and the partition plate into open communication with the other part of the interior of the vessel. 
     While the products are being steamed, the valve mechanism will occupy the position in which the space between the end wall and the partition plate is in open communication with the other part of the interior of the vessel, so that condensate can flow into said space. The passage will be shut off before steam is blown off, so that the risk of condensate being carried along with the steam exiting from said space is eliminated. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will now be explained in more detail by means of an embodiment of a steam peeling device according to the invention which is schematically illustrated in the accompanying figures. 
     FIG. 1 is a schematic cross-sectional view of a steam peeling device according to the invention. 
     FIG. 2 is a larger-scale sectional view of a valve mechanism. 
     FIG. 3 is a larger-scale sectional view of a journal construction which is used for supplying and discharging steam and for discharging condensate. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The steam peeler comprises a more or less elongated vessel  1 , which is closed by an end wall  2  near one end. 
     Near the other end of the vessel an opening is provided, which can be closed by means of a cover  3 . Cover  3  is to that end connected to an arm  5 , which can be pivoted about a pivot pin  6  by adjusting means so as to pivot cover  3  from the position illustrated in full lines in FIG. 1, in which the cover closes the vessel, to the open position  3 ′ of the cover, which is illustrated in dotted lines. In this open position products to be steamed, such as potatoes, can be deposited into the vessel via a filling hopper mounted on the end of the vessel. 
     Mounted on the outside of the vessel, on either side thereof, are co-axial journal members, by means of which vessel  1  can be rotatably supported in a frame (not shown), in such a manner that the vessel is rotatable by driving means (not shown) about an at least substantially horizontal axis of rotation, which is formed by co-axial central axes of the journal members, which axis of rotation crosses the central axis of the vessel perpendicularly between the ends of the vessel. 
     One journal member may be a massive shaft, whilst the other journal member  8  is shown in sectional view in FIG.  3 . 
     As is apparent from FIG. 3, the journal member comprises a hollow shaft  9 , which is supported by means of a bearing  10  in a frame part  11  of the frame (not shown) that supports the vessel. 
     One end of the shaft  9  is attached to a flange  12 . Flange  12  is attached by means of bolts  13  to a flange  14 , which is welded on the wall of vessel  1 . The other end of shaft  9  is rotatably journalled in an annular member  15  surrounding shaft  9 , in which a circular chamber  16  is recessed, which is in commutation with the interior of hollow shaft  9  via holes  17  formed in hollow shaft  9 . Packing means  18  and the like are provided so as to prevent leakage between hollow shaft  9  and annular member  15 . 
     A pipe  19 , which is concentrically surrounded by hollow shaft  9 , is inserted with one end into a hole formed in flange  12  and connected with its other end to an annular supporting member  20 , which is disposed in the opposite end of the hollow shaft  9  and which is fixed to shaft  9  by means of bolts  21 . 
     The end of a pipe  23  is inserted into said annular supporting member with the interposition of sealing member  22 , all this in such a manner that the annular supporting member  20  is rotatable with respect to pipe  23 . 
     As is furthermore apparent from FIG. 3, a pipe  24  is connected to annular space  16 . 
     Present in the interior of the vessel, spaced from the inner wall of vessel  1  by a short distance, is a perforated jacket  25  which is surrounded by the vessel all round. 
     Near the passage formed in flange  14 , a closed buffer plate  26  is disposed in said perforated jacket, against which steam supplied via pipes  23  and  19  during operation will impinge, which steam will subsequently flow into the space between the perforated jacket and the inner wall of the vessel, and from said space, through the perforated jacket, into the interior of the vessel. 
     Seen in the position of the vessel as shown in FIG. 1, a grid  27  is disposed near the bottom side of the vessel, on which grid products supplied via hopper  7  will be received. 
     Disposed some distance below said grid  27  and some distance above end wall  2  is a partition plate  28  in the form of a conical surface, which extends from its circumferential edge attached to the inner wall of the vessel in the direction of end wall  2 . 
     A hole or passage  28 ′ is formed in the centre of the partition plate. Attached to the boundary edge of the passage is the end of an annular supporting member  29 , which is attached with its other end to the boundary edge of a hole formed in end wall  2 . Near partition plate  28  a valve seat  30  is supported by annular supporting member  29 . A valve  31  can mate with said valve seat  30  for the purpose of shutting off passage  28 ′. Valve  31  is mounted on a valve rod  32 , which is connected with its end remote from the valve to a driving element  33 , for example a setting cylinder, by means of which valve rod  32  can be moved in its longitudinal direction. 
     Valve rod  32  is journalled, with the interposition of sealing member  34 , in a supporting housing  35  which is fixed by means of bolts  36  to the supporting member  29  that is disposed between end wall  2  and partition plate  28 . Present in housing  35  and in supporting member  29  are passages  37  and  37 ′, respectively, which passages are in open communication with the space  38  that is present between partition plate  28  and bottom plate  2 . 
     It will be apparent that in the position of valve  31  that is shown in FIG. 2, in which position valve  31  abuts against valve seat  30 , space  38  is shut off from the interior space in vessel  1 . When the valve rod  32  is moved in its longitudinal direction by means of driving element  33 , however, the valve can be moved to the position  31 ′ that is illustrated in dotted lines in the figure, in which position the interior of the vessel is in open communication with space  38  via passages  37  and  37 ′. 
     Connected to space  38  is a discharge pipe  43  (FIG.  1 ), which communicates with one end of a pipe  44  via a shut-off valve  43 ′. The other end of pipe  44  is connected to the interior of hollow shaft  9  (FIG. 3) near flange  13 . Near this connection pipe  19 , which is surrounded by hollow shaft  9 , includes a welded-on strengthening layer  45  on its outer circumference, which strengthening layer functions to prevent the pipe  19  from being attacked by condensate flowing from pipe  44 . 
     Shut-off valve  43  can be opened and closed by means of a driving element  46  mounted on shut-off valve  43 . 
     The operation of the above-described device is as follows. 
     In the upright position of the device as shown in FIG. 1, products to be steamed, such as potatoes, can be introduced into the interior of the vessel after the cover  3  has been opened. After cover  3  has been closed, steam can be introduced into the vessel via pipes  23  and  19 . 
     The steam that comes into contact with the initially cold products and the cold inner wall of the vessel and the jacket will at least partially condensate, and it can flow into space  38  via the valve  31 , which is open as illustrated in dotted lines. 
     During operation the vessel will be rotated about the horizontal axis of rotation formed by journal member  8  and the journal member that is disposed on the opposite side of the vessel, whereby the product, such as potatoes, will come into contact with steam on all sides for the purpose of steaming off the peel. 
     As already said before, a very uniform distribution of the steam over a large area takes place thereby, in that the steam present in the interior of the vessel exits via the perforated jacket  25  disposed within the vessel, which surrounds the products present in the vessel all round. 
     Once the products have been exposed to the steam sufficiently long, the supply of steam will be interrupted and valve  31  will be pressed against valve seat  30  so as to shut off the passage  28 ′. Once valve  31  is closed, valve  43 ′ can be opened for the purpose of discharging the condensate via pipe  44 , the interior of shaft  9  and pipe  24 . The steam that is present in the vessel will be discharged via pipes  19  and  23 . 
     Since valve  31  is closed while steam is being discharged from the vessel, condensate cannot be carried along by the exiting steam.