Heating apparatus

A steam heated beatershaft for use in a cooking chamber is shown in FIG. 1 having at its drive end a driven shaft (2) and at its opposite end a hollow shaft (4) which in use is connected to a steam supply whereby steam can be fed from a concentric steam chamber and respective hollow support arms into respective annular hollow rings (9). A collecting tube extends from each hollow ring through a respective hollow arm into a collection chamber mounted concentrically within the steam chamber so that as the rings (9) rotate in heating and agitating the material in the cooking chamber condensate within the hollow rings (9) is collected and transfered from the collection chamber through a discharge tube provide through the hollow shaft (4).

This invention relates to heating apparatus and more particularly to 
heating apparatus which is adapted to simultaneously agitate or stir the 
material being heated. 
While the present invention will be hereinafter described particularly with 
reference to a steam heated beatershaft for use in the cooking vessel of a 
meat processing plant it is to be understood that such use is given by way 
of example and not by limitation. 
In previous designs of steam heated beatershafts for use in cooking 
chambers it has been known to provide steam flow along elongate tubes or 
hollow beaters running co-axially relative to and rotating with a rotating 
shaft, the tubes or beaters in their rotation stirring the material being 
cooked as well as imparting heat thereto conducted through the tube walls. 
The beatershaft would normally be mounted within a vessel having a steam 
jacket positioned therearound and forming the external walls of the 
cooking vessel. 
It is an object of a preferred embodiment of the present invention to 
provide a steam heated beatershaft which provides more efficient heating 
of material within a cooking vessel in which the beatershaft is mounted, 
which enables the separation of steam and condensate, which facilitates 
the efficient removal of condensate and air, and which at the same time 
offers less resistance to rotation thus consuming less power than previous 
designs. 
Further objects of the invention will become apparent from the following 
description. 
Accordingly, one embodiment of the present invention provides a steam 
heated beatershaft comprising: 
(a) steam inlet means connected with an outer steam chamber, 
(b) outlet means to remove condensate and air connected with an inner 
co-axial collecting chamber, 
(c) a plurality of spaced apart annular hollow rings mounted about and in 
steam connection with said steam chamber and 
(d) condensate and air removal means providing a flow connection between 
each ring and said collecting chamber.

The present invention can be broadly said to reside in a steam beatershaft 
having co-axial but separated steam and condensate collecting chambers. A 
plurality of hollow rings are spaced apart along the length of the steam 
chamber to receive steam therefrom and have condensate collecting tubes 
collecting the condensate formed within the annular rings and taking it to 
the condensate collecting chamber for subsequent removal from the 
beatershaft. Any air or non-condensable gas which gains entry or enters 
with the steam is also collected and taken to the collecting chamber for 
subsequent removal with the condensate. 
It has been found that by the use of a plurality of steam receiving spaced 
apart annular rings in the manner above mentioned a particularly efficient 
steam heating and beating operation is effected on the material within a 
cooking chamber in which the beatershaft is mounted to such an extent that 
it is envisaged that the normally provided outer steam jacket could be 
dispensed with. It is believed that this efficiency of heating is due both 
to the large heating surface provided by the plurality of steam heated 
rings together with the characteristics of steam and condensate flow and 
their separation in the beatershaft and the efficient removal of air or 
gas which when present inhibits efficient heat exchange. 
Reference will now be made to the accompanying drawings where one 
embodiment of the invention is shown by way of example and is referenced 
generally by arrow 1. 
The beatershaft 1 has at its drive end a shaft 2 with keyway 3 and at its 
front end a hollow shaft 4. The shaft 4 in use will be connected to a 
steam supply whereby steam passing through steam inlets 5 will be fed to a 
steam chamber 6 past a spider 7 and hence through hollow arms 8 to a 
respective annular hollow ring 9. 
Co-axially mounted within the steam chamber 6 is a collection chamber 10 
connected to each annular ring 9 via collecting tubes 11 passing through a 
respective arm 8. 
The arms 8 assist in agitation and heating and in the latter regard 
particularly contribute to the heat exchange adjacent to and in 
conjunction with the surface of the chamber 10. 
The outer end 11A of each tube 11 is bent over and extends into an opening 
13 associated with a support 12 and a guide 14 whereby as the ring 9 
rotates in the direction indicated by arrow A condensate formed therein is 
caused to travel by centrifugal force along the inside of the exterior 
wall of the ring 9 and is then guided by the guide plate 14 into the 
opening 13 and via the tube 11 for collection along with air or 
non-condensable gas in the chamber 10. 
In previous designs of beatershafts the centrifugal force due to rotation 
of the beatershaft has tended to prevent the efficient collection of 
condensate as the centrifugal force tended to counteract the falling of 
the condensate under gravity to enable it to be collected. However by 
utilizing the collecting tube 11 the condensate is in fact scooped up as 
the ring 9 rotates so that the centrifugal force tending to hold the 
condensate against the exterior wall of the ring 9 is in fact utilized in 
providing for an efficient collection of the condensate. The hydrostatic 
head along the length of the tube 11 results in the condensate so 
collected being transferred efficiently along the tube 11 into the 
collecting chamber 10 along with any entrained air or non-condensable gas. 
Two support arms 8 only may be fitted to each annular ring 9 as shown in 
FIG. 5 in which case the arms in alternate ring assemblies may be at 
90.degree. to each other so as to facilitate free flow of material 
therethrough while at the same time promoting agitation of material. 
Alternatively a plurality of support arms 8 may be fitted to each annular 
ring 9 with the arms 8 in alternate ring assemblies at a suitable angle to 
each other to facilitate free flow and to promote agitation of material. 
In all cases the positioning of the support arms 8 and sets of blades 15 
are such as to ensure the rigidity of the resulting structure. The blades 
15 are seen mounted by means of gussets 16 on respective rings 9 with the 
blades 15 in use agitating the material and may be angled to also 
facilitate the movement e.g. the forward feeding of the material and the 
resisting of any backward movement, these functions additionally being 
achievable by the positioning of the gussets 16. 
Ring support members 17 also serve to control the movement of the material 
relative to the rings 9. 
The desired movement of material relative to the beatershaft 1 will depend 
on the type of cooking or drying operation being effected. Thus in a batch 
system the material will be loaded in at one or more points and discharged 
after cooking/drying. To achieve the desired discharge patterns the 
blading 15 could be suitably angled and if discharge at two separate 
points was required for example the blading 15 could be set at different 
angles to enable this to take place. 
In some systems the beatershaft 1 could be rotated in one direction for 
cooking or drying and then counter rotated for discharge to take place and 
again the blading 15 would be required to accommodate this. 
In a continuous system the material is loaded in at a particular point and 
withdrawn again at a different point. The blades 15 in such case are 
disposed to promote the desired movement of the material relative to the 
beatershaft 1 and/or reliance can be placed on displacement of the 
material i.e. movement which relies on material filling up the space left 
by the material that has been discharged. 
While a plurality of separate rings 9 are shown it is envisaged that in an 
alternative embodiment a spiral tube or spiral segments could instead be 
utilized. 
Again, in order to facilitate flow of condensate through the condensate 
chamber 10 the walls of the chamber 10 may it is envisaged be tapered as 
indicated in outline in FIG. 2 and referenced 10A. In this case the taper 
of the condensate chamber 10 would promote the flow of condensate towards 
the wider end. 
To allow for relative thermal expansion of the chamber 10 its front end 
adjacent the front spider 7 will generally be free to slide, the rear 
chamber walls adjacent a rear spider 18 generally being fixed or vice 
versa. A condensate collecting and air removal tube 19 is shown extending 
through the shaft 4 and having an inner end 19A extending through and 
secured to a blanking bush 20 which is a close clearance in a hole at the 
inner end of shaft 4 whereby as the chamber 10 rotates condensate and air 
collected therein then passes down the tube end 19A for removal. 
As an alternative to further facilitate the separation of steam and 
condensate flows it is possible to arrange that steam alone be introduced 
through a hollow shaft at one end with condensate and air removed via a 
collecting tube introduced through a hollow shaft at the opposite end. 
It is desirable that as far as possible air is kept out of the system and 
when the shaft is first put into operation after being idle that the air 
within the system is displaced as speedily as possible. 
It has been found that with the provision of the steam and condensate flow 
paths such as in the embodiment of the invention above described a 
positive circulation of the steam and sweeping out of the air together 
with the elimination of condensate is achieved. 
It is mentioned that whilst the two outermost condensate collecting tubes 
11B and 11C are not directly coupled to the collecting chamber 10, 
condensate exiting from those particular tubes will in fact be collected 
with the condensate of the next adjacent ring 9. Similarly condensate 
forming in the steam chamber 6 will spill into any of the plurality of 
support arms 8 and thence be collected with condensate in the annular ring 
tubes 9 as earlier described. 
With the annular rings 9 providing an increased heating surface area for a 
given physical size compared with previous arrangements, less resistance 
to rotation of the beatershaft in the material is presented and thus 
substantially lower horse power drives may be utilized. 
Various equipment would be desirably used in conjunction with the 
beatershaft 1 for example steam straps and a steam bleed-off for the 
condensate tube 19 as a reduced or blocked flow of condensate through the 
tube 19 could result in steam being generated therein and blocking further 
condensate flow. 
Where in the aforegoing description reference has been made to specific 
components or integers of the invention having known equivalents then such 
equivalents are herein incorporated as if individually set forth. 
Although this invention has been described by way of example and with 
reference to one particular embodiment thereof it is to be understood that 
modifications or improvements may be made thereto without departing from 
the scope of the invention as defined in the appended claims.